Article

From apple to applesauce: Processing effects on dietary fibres and cell wall polysaccharides

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Abstract

Modifications in dietary fibre content of apples during industrial processing into applesauce were investigated. Samplings with different post-harvest storage times were performed at five different processing steps (apple sorting, cooking, refining, sugaring and pasteurisation) and the samples examined for their insoluble, soluble and total fibre contents, following the AOAC method. Total fibres were also estimated through preparation of alcohol-insoluble solids and polysaccharide compositions of the various fibre residues were determined. Total fibre content decreased from apple to applesauce from 2.4 to 1.7 g for 100 g of fresh weight and the soluble fraction increased. Fibre loss and soluble/insoluble redistribution occurred during processing. Refining triggered a loss of insoluble polysaccharides whilst cooking and, surprisingly, sugaring led to pectin solubilisation and further degradation due to prolonged heating. These pectic changes, moreover, seemed to be dependent on the post-maturity stage of the apples.

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... The fiber fraction The production of applesauce with added sugars is interesting because it involves several stages of processing. ColinHenrion et al. included sorting (damaged products are removed), cooking, refining through a 1.2-mm filter, the addition of glucose-fructose sirup and pasteurization (Colin- Henrion et al. 2009). The total fiber content (g/100 g of fresh matter) decreased by 28% between the whole apple and the corresponding compote, notably due to the addition of sugars and the removal of the skin (refining), which is rich in insoluble fibers. ...
... For Batch A, the increase in total fiber content after cooking is due to both soluble and insoluble fiber. For the authors, two possible explanations are "the loss of some internal soluble materials (by dripping of the sugar solution) or a sampling bias, namely, a change in the skin/pulp/seed ratio between fresh apples and cooked apple broth" (Colin-Henrion et al. 2009). According to the authors, during the processing of apples into applesauce, two main mechanisms can affect the fiber content: 1) heating, which leads to a depolymerization of the pectins; and 2) mechanical separation of the most resistant fractions, namely, pips, skin and carpels (Colin-Henrion et al. 2009). ...
... For the authors, two possible explanations are "the loss of some internal soluble materials (by dripping of the sugar solution) or a sampling bias, namely, a change in the skin/pulp/seed ratio between fresh apples and cooked apple broth" (Colin-Henrion et al. 2009). According to the authors, during the processing of apples into applesauce, two main mechanisms can affect the fiber content: 1) heating, which leads to a depolymerization of the pectins; and 2) mechanical separation of the most resistant fractions, namely, pips, skin and carpels (Colin-Henrion et al. 2009). The soluble fiber content increases after cooking: the applied temperature (85 C) may have contributed to the solubilization by depolymerization of the cell wall polysaccharides previously bound to the insoluble fraction, most probably the pectins. ...
Article
Epidemiological studies suggest that the protective effects of fruits against chronic diseases may vary according to their extent of processing. We therefore reviewed what the scientific literature states about the potential mechanisms underlying this “processing” effect by focusing on the most significant nutritional properties, namely, the nutritional density of bioactive compounds, the digestive bio-accessibility of nutrients, and the antioxidant, satietogenic, alkalizing and glycemic potentials. When possible, we have ranked fruits according to the international NOVA classification as un-/minimally processed, processed (mainly with added sugars), and ultra-processed fruits. Our literature review confirms that the more fruits are processed, the lower are their alkalizing, antioxidant and satietogenic potentials. For the glycemic index, the results are more difficult to interpret because fruits are a significant source of fructose with a very low glycemic index that "distorts" the “processing” effect. However, fruits in syrup tend to have a higher glycemic index, probably because of the highly bioavailable added sugars. Overall, the destructuration of the fruit fibrous matrix by thermal and mechanical treatments, combined with the addition of simple sugars, constitute the treatments that most degrade the fruit nutritive quality by diluting the nutritional density and attenuating the "matrix" effect. The new technological processes described as "nonthermal" (e.g., pulsed electric fields, high pressures, supercritical CO2, radiation, etc.) seem promising as they limit vitamin C and antioxidant phytonutrient losses in fruit while allowing satisfactory storage time. To preserve fruit longer, drying appears to be an interesting alternative to maintain the health potential of fruit, although it causes antioxidant losses. Finally, although "5 fruits and vegetables a day" is a well-known nutritional recommendation, in view of the results reviewed here, it would be relevant to be precise and include "preferably minimally processed".
... It is common to fill the hot apple puree immediately after refining into all sorts of containers such as bottles, glass jars or metal cans. Sometimes, immediate bottling is not possible, so that apple puree remains in a heated holding tank (Featherstone, 2016) for up to 30 minutes at 85 °C (Colin-Henrion, et al., 2009). The hot apple puree is then filled into the containers, which have to be closed at 88 °C to ensure a safe product (Root & Barrett, 2005). ...
... Both methods express the quantity of cell walls after removing soluble solids by water or alcohol, respectively, and drying. They were both used in apple purees, WIS for example by Schijvens, et al. (1998) and AIS by Colin-Henrion, et al. (2009) and Le Bourvellec, et al. (2011). ...
... As the puree is forced through sieve openings of a chosen diameter, carpels and peel are retained whereas cell clusters that are larger than the sieve openings tend to be separated into individual cells when they pass through the sieve. As the retained carpels and peel contain a higher proportion of cell wall than apple flesh (Massiot & Renard, 1997), the dry matter content of the puree is reduced (Colin-Henrion, et al., 2009). Depending on the refining device, both the pulp content and the particle size (Schijvens, et al., 1998) or only the pulp content (Rao, et al., 1986) are reduced. ...
Thesis
Full-text available
The objective of this thesis was to understand how structural characteristics in raw apples can be linked to structural factors in purees after cooking and tissue fragmentation. Structural characteristics of the fruit were modulated by cultivars, agricultural practices and maturation, and process conditions (thermal: 50–95 °C and mechanical: 100–3000 rpm) were modulated in a cooker-cutter during processing. Puree’s structure (volume occupied by particles, particle size, serum viscosity) and texture (viscosity, yield stress, G’ and G’’) were then analysed and compared between raw materials and process conditions. Pectins were extracted and their chemical composition and structure were correlated to puree’s structure. Particle size appeared to be the most important determinant of puree’s texture when there is no dilution or concentration of the fruit tissue. The extent of cell adhesion (defined by pectin structure and composition) determined particle size more than individual cell size (defined by varietal effects or agricultural practices). Other structural factors only contributed to puree’s texture once particle size was constant. Tissue fragmentation, determining particle size during processing, was principally affected by shear intensity. Post-harvest maturity of the raw apples and high temperatures (95 °C) induced pectin degradation, especially rhamnogalacturonan I side chain hydrolysis, and solubilisation. This led to reduced cell adhesion and tissue fragmentation was additionally favoured. The results deepened the understanding of tissue fragmentation and textural changes during processing and provided guidelines for industry to manage diversity and heterogeneity of raw fruits during processing.
... Moreover, apple flesh contains a higher content in pectic components while carpels are richer in xyloglucans and glucans. Colin-Henrion et al. (2009) thus recorded a highly significant decrease in the insoluble fibre content of a hot-break applesauce after the refining step. ...
... On pear, Renard (2005a) shows that after 1 h of cooking, 65% of the original flavan-3-ols and 40% of the original 5 0 -caffeoylquinic acid are still detectable in the pear tissue. During cooking the pectin fractions are degraded becoming more soluble and of lower molecular weight (Renard, 2005a;Colin-Henrion et al., 2009), while xylans and cellulose are not affected (Renard, 2005a). ...
... Greensleeves) to 25 mg/g (cv. Jolyne) fresh weight (FW), which was consistent with previously published works (15-24 mg/g of FW) Massiot and Renard, 1997;Renard, 2005b;Colin-Henrion et al., 2009). The sugar composition of the AIS of the different apple varieties was very close (Table 1). ...
Article
Apple fruit is well known for its health properties, ascribed to its content in both phenolics and fibres. As more and more apples are consumed after processing, there is a need to understand the impact of the conventional process on the nutritional potential of applesauce. We have investigated the variation in composition between fresh and processed apples of 12 cultivars, focussing on polysaccharides and polyphenols. The polysaccharide content estimated in the alcohol insoluble solid (AIS) of the apple flesh varied from 17 (cv. Greensleeves, obtention TMR 7 A 82) to 25 (cv. Jolyne) mg/g fresh weight. The AIS contents varied from 15 to 32 mg/g fresh weight in applesauce. The applesauces were fractionated into serum, containing low concentrations (<5 mg/g) of soluble fibres, and particles concentrating the fibres (40-60 mg/g) and the cellulose (>30% of the AIS). Total phenolic concentrations varied in the flesh from 578 (cv. Golden Delicious) to 1596 mg/kg fresh weight (cv. 3535), and in the peel from 1658 (cv. Greensleeves) to 7658 mg/kg fresh weight (cv. Sinta). The applesauces contained flavonols, coming from the skin, and slightly higher concentration of dihydrochalcones coming from the pips than the flesh. A dihydrochalcone oxidation product was also detected. The concentration of hydroxycinnamic acids and flavan-3-ols was decreased in proportions depending on the cultivar. The flavan-3-ols were concentrated in the particles of the applesauce. The composition of applesauce thus appeared to be very close to that of apple flesh. (C) 2011 Elsevier Inc. All rights reserved.
... The AIS content of raw apples decreased over post-harvest storage. The same trend was observed by Fischer and Amado (1994) and the values were similar to those found in literature (15-27 mg/g FW) (Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009;Le Bourvellec et al., 2011;Massiot & Renard, 1997;Renard, 2005). The main sugars found in the AIS of raw apples were glucose and galacturonic acid, corresponding to cellulose and pectins, respectively. ...
... No mannose was detected in the serum AIS. Colin-Henrion et al. (2009) and Le Bourvellec et al. (2011) found similar trends regarding the amount and composition of the AIS in the pulp and the serum. ...
Article
The texture of pureed fruits and vegetables depends primarily on the original tissue structure and cell wall (CW) properties. However, how variations in the raw fruits' cellular and molecular structure determine the rheological behaviour of the purees is little understood, though pectin degradation appears to play a key role. Cultivars, fruit load and post-harvest storage were used to obtain raw apples with different tissue structures, which were processed into purees under simulation of an industrial process. The rheological behaviour of the purees was then compared to particle size, pulp wet mass and serum viscosity. The polysaccharide composition of soluble and insoluble CW material were determined after preparation of alcohol insoluble residue. Macromolecular size and molar mass distributions of soluble pectins were analysed using high performance size-exclusion chromatography coupled to multi-angle laser light scattering and online viscometry. Variations in the raw material, especially induced by post-harvest storage, generated a wide range of different puree's textures. Rheological behaviour of apple purees was driven by particle size, which decreased during prolonged post-harvest storage due to reduced cell adhesion. This was correlated with pectic side chain hydrolysis and modifications in pectin molar mass and structure. Similar trends during storage were observed with different apple cultivars and agricultural practices.
... A natural composition of cell wall or storage non-starch polysaccharides and lignin derived from fruit and vegetables are considered as a dietary fibre. A recommended consumption dose of foods rich in dietary fibre is about 30-45 g per day for adults although now it is only about 20 g per day in highly developed countries (Bach Knudsen, 2001;Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009;McCann et al., 2011). Dietary fibre influences human health by decreasing cholesterol levels in blood, reducing the absorption of sugar and sugar's response after eating, normalizing blood lipids level and reducing energy density which can attenuate the risk of obesity (Brownlee, 2011;Colin-Henrion et al., 2009;Comino, Collins, Lahnstein, Beahan, & Gidley, 2014;Kahlon & Smith, 2007;Kendall, Esfahani, & Jenkins, 2010;Topping, 2007;Zhu, Du, Zheng, & Li, 2014). ...
... A recommended consumption dose of foods rich in dietary fibre is about 30-45 g per day for adults although now it is only about 20 g per day in highly developed countries (Bach Knudsen, 2001;Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009;McCann et al., 2011). Dietary fibre influences human health by decreasing cholesterol levels in blood, reducing the absorption of sugar and sugar's response after eating, normalizing blood lipids level and reducing energy density which can attenuate the risk of obesity (Brownlee, 2011;Colin-Henrion et al., 2009;Comino, Collins, Lahnstein, Beahan, & Gidley, 2014;Kahlon & Smith, 2007;Kendall, Esfahani, & Jenkins, 2010;Topping, 2007;Zhu, Du, Zheng, & Li, 2014). Besides health-related properties, polysaccharides composed of dietary fibre have a great value for the food industry as functional components. ...
Article
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A new food matrix made of modified cell wall polysaccharides (MPS) from apple pomace was developed. In this experiment an effect of metal divalent ions: calcium, magnesium and iron ions on rheological properties of MPS was studied. An increase of Ca2+ or Fe2+ concentration in MPS suspensions significantly increased viscosity as well as elastic (G') and viscous (G" moduli. Contrary, Mg2+ addition caused a significant decrease of viscosity, G' and G" Herschel-Bulkley's model fitted to shear stress vs. shear strain (flow curves) showed that calcium and iron ions increased pseudoplasticity and viscosity proportionally to concentration. The addition of any studied metal ions to MPS increased thixotropic effect. A temperature at the gel point increased when concentration increased to 9 mM, then the gel points appeared at lower temperatures again for higher concentrations. This study showed that the MPS is an effective texture modifier with a controlled function by metal ions.
... The dough preparations for all cereal types show relatively 293 smaller increases in the amounts of solubilised WEAX and WEBG ( Table 1), in line 294 with the milder process compared to the final foods. 295 Others have described a transition of insoluble to soluble dietary fibre after 296 processing of various cereal flours, fruits and vegetables, ( Colin-Henrion et al., 2009;297 Siljeström et al., 1986;Stojceska et al., 2010;Theander and Westerlund, 1987;298 Vasanthan et al., 2002). Colin-Henrion et al. reported an increase of 39% soluble 299 dietary fibre after the production of apple sauce from apples ( Colin-Henrion et al., 300 2009). ...
... The dough preparations for all cereal types show relatively smaller increases in the amounts of solubilised WEAX and WEBG ( Table 1), in line with the milder process compared to the final foods. Others have described a transition of insoluble to soluble dietary fibre after processing of various cereal flours, fruits and vegetables, ( Colin-Henrion et al., 2009;Siljestr€ om et al., 1986;Stojceska et al., 2010;Theander and Westerlund, 1987;Vasanthan et al., 2002). Colin-Henrion et al. reported an increase of 39% soluble dietary fibre after the production of apple sauce from apples ( ColinHenrion et al., 2009). ...
Article
The effects of archetypal food processing conditions (dough formation, baking, extrusion, and cooking/boiling) on dietary fibre structure and extractability from the endosperm flours of rye, hull less barley and wheat are reported. For all flours and processes, the distributions of soluble/insoluble cell wall dietary fibre as well as the chemical composition (arabinoxylan (AX) branching patterns, β-glucan DP3/DP4 (DP = degree of polymerisation) ratios) of solubilised fractions were characterised. The results show that overall the total amounts of AX and β-glucan (BG) were not significantly affected by processing but that there were similar increases in the soluble fibre fraction (20-29%) for baked, extruded, and boiled/cooked processes for each flour, with lower (10-15%) increases for all flours processed into dough. In all cases, solubilised fractions of AX and BG had very similar chemical structures to the starting flour, suggesting that increased solubilisation was not due to specific chemical fractions. Confocal images illustrate loosely-held associations of β-glucan with the cell walls of processed foods in contrast to some of the arabinoxylans which appear more tightly held within the residual cell walls. The similarities in behaviour across the three grains are consistent with mechanical treatments during food preparation resulting in similar extents of disentanglement of physically-constrained AX and BG leading to their partial solubilisation.
... Concerning the refined (Ra) purees, an expected clear reduction was obtained for both AIS content (in DW) and viscosity ( 100 ) after refining (Table 32). That could be due to the loss of insoluble fibers in the removed particle fraction (Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009) leading to a loss of puree viscosity (Espinosa-Muñoz, To, Symoneaux, Renard, Biau, & Cuvelier, 2011;Leverrier, Almeida, & Cuvelier, 2016). ...
... al., 2015). These observations were in accordance with the increase of soluble fiber fractions and total polysaccharide contents after apple cooking(Colin- Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009).-The bands at 1610-1620 cm -1 (1614 cm -1 in NF; 1618 cm -1 in FD) have been reported to correspond to the vibration of C=O from protein or pectic acid ester(Abidi, Cabrales, & Haigler, 2014). ...
Thesis
This thesis aimed to show how vibrational spectroscopy including near infrared (NIR), mid infrared (MIR), Raman and NIR hyperspectral imaging (NIR-HSI) coupled with advanced chemometrics can highlight the variability and heterogeneity of both, raw apples and processed purees. Experimental trials were designed to modulate several factors in orchard (varieties, agricultural practices), during post-harvest storage (4°C) and processing (temperature, grinding and refining) in order to modify properties and composition of apples and purees. An efficient approach using NIR-HSI allowed illustrating the distribution of total sugars and dry matter inside apples. The inter-batch variability of apples and the intra-batch variability between individual apples intensively changed the cooked purees. MIR spectroscopy was the best tool to detect the variability of purees and assess their biochemical (soluble solids, acidity, dry matter, fructose, sucrose and malic acid), rheological (viscosity and viscoelastic moduli) and textural (particle size and volume) properties. Good linear correlations were found between apple texture and puree viscosity, as well as between apple and puree acidity, soluble solids and dry matter. Therefore, VIS-NIR and NIR techniques allowed to predict the taste and texture of purees from the non-destructive spectra of apples. Besides, MIR spectroscopy can guide puree formulation from spectra of single-variety purees. Our innovative approaches could provide objective data to better manage apples and to adapt processing conditions according to their initial properties. The ultimate goal is to improve the quality of fresh and processed fruits while reducing losses.
... Others have described a transition of insoluble to soluble dietary fibre after processing of various cereal flours, fruits and vegetables, (Colin-Henrion et al., 2009;Siljestr€ om et al., 1986;Stojceska et al., 2010;Theander and Westerlund, 1987;Vasanthan et al., 2002). Colin-Henrion et al. reported an increase of 39% soluble dietary fibre after the production of apple sauce from apples (Colin-Henrion et al., 2009). ...
... Others have described a transition of insoluble to soluble dietary fibre after processing of various cereal flours, fruits and vegetables, (Colin-Henrion et al., 2009;Siljestr€ om et al., 1986;Stojceska et al., 2010;Theander and Westerlund, 1987;Vasanthan et al., 2002). Colin-Henrion et al. reported an increase of 39% soluble dietary fibre after the production of apple sauce from apples (Colin-Henrion et al., 2009). Østergård et al. (1989 reported increases of 13e18% soluble dietary fibre from extruded barley products. ...
Article
The effects of archetypal food processing conditions (dough formation, baking, extrusion, and cooking/ boiling) on dietary fibre structure and extractability from the endosperm flours of rye, hull less barley and wheat are reported. For all flours and processes, the distributions of soluble/insoluble cell wall dietary fibre as well as the chemical composition (arabinoxylan (AX) branching patterns, b-glucan DP3/DP4 (DP = degree of polymerisation) ratios) of solubilised fractions were characterised. The results show that overall the total amounts of AX and b-glucan (BG) were not significantly affected by processing but that there were similar increases in the soluble fibre fraction (20e29%) for baked, extruded, and boiled/ cooked processes for each flour, with lower (10e15%) increases for all flours processed into dough. In all cases, solubilised fractions of AX and BG had very similar chemical structures to the starting flour, suggesting that increased solubilisation was not due to specific chemical fractions. Confocal images illustrate loosely-held associations of b-glucan with the cell walls of processed foods in contrast to some of the arabinoxylans which appear more tightly held within the residual cell walls. The similarities in behaviour across the three grains are consistent with mechanical treatments during food preparation resulting in similar extents of disentanglement of physically-constrained AX and BG leading to their partial solubilisation.
... The pasteurization process carried out to stabilize the products destroys part of the matrix affecting dietary fiber. In fact, TDF content of several vegetables, such as carrots, potatoes, peas, etc., was reduced by applying different thermal methods [27][28][29]. On the other hand, the pasteurization process can solubilize dietary fiber, improving soluble/insoluble fiber ratio (Table 1) as it was observed before in onion by-products [18]. Thus, PP is a value-addedproduct due to the major SDF compared to NPP. ...
... Thus, pasteurization degrades some components but improves the availability of others and can generate new compounds, different from those in the fresh samples, mainly through reactions such as the Maillard reaction. carrots, potatoes, peas, etc., was reduced by applying different thermal methods [27][28][29]. ...
Article
Full-text available
After orange processing, different by-products are generated, i.e., peels, seeds and pulps. The pulp is highly perishable, being an unstable food matrix that needs a preservation process to be stored and used again in the food production chain. Pasteurization is the technique of choice before aseptically packaging and storing under refrigerated conditions. In this study, the effect of pasteurization has been evaluated on the chemical, functional and sensorial profiles. Ash content decreased (p < 0.05) after the thermal treatment. Indeed, magnesium, calcium and zinc diminished, although copper was found to be higher (p < 0.05) in the pasteurized product. Total dietary fiber decreased (p < 0.05), but soluble dietary fiber raised (p < 0.05) due to hydrolysis caused by pasteurization. SDF:IDF ratio, hydration properties, and fat binding capacity were improved. Total soluble phenolic compounds remained similar but FRAP and DPPH scavenging activity decreased (p < 0.05) in the pasteurized by-product. Regarding the sensorial profile, pasteurization produced darkening, appearance of a cooked smell and an increase in bitterness. Therefore, pasteurization deteriorates the sensorial profile being able to change the attributes of an added-pasteurized-pulp juice; however, it is a good choice to preserve the orange pulp by-product to formulate food products different from juices or other beverages.
... Several studies have addressed the beneficial effects of bioactive polysaccharides in obesity, insulin resistance, nonalcoholic fatty liver disease, inflammation, and diabetes (Chen et al., 2015Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009;Hu et al., 2016;Huang et al., 2016;Li, Chen, Jin, & Chen, 2009;Li et al., 2010Li et al., , 2011Li et al., , 2015Lv et al., 2009;Yang et al., 2013;Zhang, Nie, Huang, Feng, & Xie, 2014). A growing amount of evidence highlights that ROS produced by metabolic processes have a wide variety of pathological effects, such as causing DNA damage, carcinogenesis, insulin resistance, mitochondrial dysfunction and age-related cellular degeneration (Droese, Hanley, & Brandt, 2009;Kowaltowski & Vercesi, 1999). ...
... The pomace represents a rich source of potentially bioactive apple ingredients [3], including polyphenols and flavonoids [4]. However, a major class of phytochemicals commonly found in apple pomace is the polysaccharides, which play an important role as free radical scavengers in the prevention of oxidative damage in living organisms and can be exploited as novel antioxidants [5,6]. ...
Article
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Scope: Apple pomace polysaccharide (APP), a free radical scavenger, is one of the major compounds derived from apple pomace. However, whether APP has beneficial effects on metabolic disorders is still unknown. Methods and results: In the present study, water-soluble APP was isolated from the pomace of the locally abundant 'Qinguan' apple and chemically characterized. Then APP was orally administrated to high-fat diet (HFD)-induced obese mice. We found that APP significantly reduced HFD-induced body weight gain and ameliorated HFD-induced hepatic metabolic disorders and oxidative stress. In a palmitate-loaded HepG2 cell model, APP protected the cells from palmitate-induced insulin resistance and loss of viability by suppressing mitochondrial ROS and rescuing mitochondrial respiratory function. Conclusion: Our work suggests that APP, a promising bioactive food component, successfully improved obesity-associated hepatic metabolic disorder, most likely though the activation of hepatic mitochondrial function and the suppression of mitochondria oxidative stress. This article is protected by copyright. All rights reserved.
... Colin-Henrion, Mehinagic, Renard, Richomme, and Jourjon (2009) also found an increase in fibre content after different processing as cooking or sugaring. The reduction in DF content in FC from sterilised by-products could be due to the partial chemical degradation of cellulose and hemicellulose into simple carbohydrates, and to the solubilisation and fragmentation of pectic polysaccharides as result of sterilisation (Colin-Henrion et al., 2009). According to Rehman, Islam, and Shah (2003), the extent of fibre losses became higher after sterilisation than after normal cooking, due to temperature and pressure conditions. ...
Article
Onion by-products, Paste and Bagasse, were used to produce fibre concentrates (FCs), which were studied for dietary fibre (DF) content, physicochemical properties, effects on glucose adsorption, in vitro glucose diffusion, alpha-amylase activity and starch digestibility. FC dietary fibre was composed of cellulose and pectic polysaccharides with different degree of branching. FCs had lower bulk densities, and higher oil-holding and cation exchange capacities, as well as higher hydration properties, than cellulose. Onion FCs had the desired physicochemical properties as fibre sources or low-calorie bulk ingredients in food applications. Both onion FCs were found to have higher glucose-adsorption capacity than cellulose. The retardation of glucose diffusion by FCs were higher than cellulose. All FCs reduced the glucose production rate by inhibiting alpha-amylase activity, and decreased starch digestibility. The results verified the hypoglycaemic effect and the in vitro antidiabetic potential of onion by-product FCs.
... Many studies have highlighted that the consumption of foods rich in dietary fi bre may improve health: the recommended intake is 30-45 g per person per day, yet the current consumption of fi bre in the West is only around 20 g/day person. Because processing operations and their arrangement during complete processing may play a role in fi bre content and in the type of fi bre remaining in the fi nal product, the processing of the sample is important (Colin-Henrion et al., 2009). This review summarises recent research regarding the eff ect of food processing on the physochemical properties of dietary fi ber. ...
Article
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Products derived from the manufacturing or processing of plant based foods: cereals, fruits, vegetables, as well as algae, are sources of abundant dietary fibre. Diets high in dietary fibre have been associated with the reduced risk of cardiovascular disease, diabetes, hypertension, obesity, and gastrointestinal disorders. These fibre-rich products and byproducts can also fortify foods, increase their dietary fibre content and result in healthy products, low in calories, cholesterol and fat. Traditionally, consumers have chosen foods such as whole grains, fruits and vegetables as sources of dietary fibre. Recently, food manufacturers have responded to consumer demand for foods with a higher fibre content by developing products in which highfibre ingredients are used. Different food processing methods also increase the dietary fiber content of food. Moreover, its chemical and physical properties may be affected by food processing. Some of them might even improve the functionality of fibre. Therefore, they may also be applied as functional ingredients to improve physical properties like the physical and structural properties of hydration, oil-holding capacity, viscosity. This study was conducted to examine the effect of different food processing methods on the physicochemical properties of dietary fibre.
... 21 d.m.) had higher IDF content than SDF content (3.12 6 0.12 g 100 g 21 d.m.). The high content of IDF was due to the skin and seeds, which are rich in nonpolysaccharide insoluble material(Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009) and the maqui berry is characterized by containing 3-4 seeds. The IDF content increased value from 50 to 808C due to the presence of seeds that were not greatly affected by drying temperature. ...
... The amount of soluble pectin was significantly increased compared to the non-heated purees, due to the thermosolubilization of pectin. Indeed, elevated temperatures may 1) change the interactions between pectin and cell wall components promoting pectin dissociation and leaching, and 2) promote pectin depolymerization by β-elimination and acid hydrolysis, releasing some smaller soluble pectin molecules from the cell wall network (Christiaens et al., 2012;Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009;Sila et al., 2009). ...
Article
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Protein and fiber, especially pectin, can form complexes at acidic pH. Studies on these complexes under actual food conditions are scarce. The aim of this work was to study interactions between whey proteins and blueberry puree, in particular its pectin, and to evaluate the impact on the functionality of the puree alone or incorporated into a model beverage. After the addition of a whey protein isolate (WPI) into purees at pH 3.5 or 6.5, the soluble pectin and protein contents and the viscosity of the resulting mixtures were determined. The decrease in the solubility of pectin (80%) and proteins (94%) indicated the formation of protein-pectin complexes by electrostatic interactions at pH 3.5, contributing to increase the mixture viscosity. The amount of soluble pectin in blueberry limited the formation of complexes when more WPI was added (5%). Heating the puree prior to the WPI addition solubilized pectin, which limited the formation of insoluble complexes and reduced the viscosity increase. The solubility of the blueberry polyphenols did not decrease after WPI addition. Finally, the non-heated puree enriched in WPI was used to prepare smoothies. This time, the protein-pectin complexation, probably reinforced by the final pasteurization of the smoothies, contributed to reduce the smoothie viscosity and can be explained in particular by particles of smaller sizes. Although the smoothie stability can be improved, the interactions between blueberry pectin in a puree and whey proteins allowed to design a novel functional ingredient that may be helpful in formulating beverages rich in fiber and protein.
... The proportion differences may be related with the drying temperature. When HP drying is carried out at 75 °C, heating effects result in the depolymerization of cell wall polysaccharides and a corresponding increase in pectin-associated sugars such as arabinose and galactose [21]. ...
Article
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Dried litchi pulp has been used in traditional remedies in China for many years to treat various diseases, and the therapeutic activity has been, at least partly, attributed to the presence of bioactive polysaccharides. Polysaccharide-protein complexes from vacuum freeze-(VF), vacuum microwave-(VM) and heat pump (HP) dried litchi pulp, which were coded as LP-VF, LP-VM and LP-HP, were comparatively studied on the physicochemical and immunomodulatory properties. LP-HP had a predominance of galactose, while glucose was the major sugar component in LP-VF and LP-VM. Compared with LP-VF and LP-VM, LP-HP contained more aspartate and glutamic in binding protein. LP-HP also exhibited a stronger stimulatory effect on splenocyte proliferation at 200 μg/mL and triggered higher NO, TNF-α and IL-6 secretion from RAW264.7 macrophages. Different drying methods caused the difference in physicochemical properties of polysaccharide-protein complexes from dried litchi pulp, which resulted in significantly different immunomodulatory activity. HP drying appears to be the best method for preparing litchi pulp to improve its immunomodulatory properties.
... Smoothies were identified as a convenient carrier format to deliver high levels of PPs and DF. Both apple DF and PPs were selected because of their abundant health-promoting activities and desirable processing properties [29]- [33]. A blackcurrant PP extract was also included as it contained vitamin C and additional phenolic compounds such as anthocyanins, hydroxybenzoic acids, hydroxycinnamic acid compounds [34], [35], with their associated health benefits [36], [37]. ...
Article
Attempts to add fibre and polyphenols (PPs) into popular beverages present challenges related to the properties of finished products such as smoothies. Consumer acceptability, viscosity and phenolic composition of smoothies containing high levels of fruit fibre (2.5-7.5 g per 300 mL serve) and PPs (250-750 mg per 300 mL serve) were examined. The changes in total extractable PP, vitamin C content, and colour of selected smoothies over a storage stability trial (4°C, 14 days) were compared. A set of acidic aqueous model beverages were prepared to further examine the effect of two different heat treatments on the stability and extractability of PPs. Results show that overall consumer acceptability of high fibre and PP smoothies was low, with average hedonic scores ranging from 3.9 to 6.4 (on a 1-9 scale). Flavour, texture and overall acceptability decreased as fibre and polyphenol contents increased, with fibre content exerting a stronger effect. Higher fibre content resulted in greater viscosity, with an elevated PP content increasing viscosity only slightly. The presence of fibre also aided the stability and extractability of PPs after heating. A reduction of extractable PPs, vitamin C content and colour intensity of smoothies was observed after a 14-day storage period at 4°C. Two heat treatments (75°C for 45 min or 85°C for 1 min) that are normally used for beverage production, did not cause significant reduction of total extracted PPs. It is clear that high levels of added fibre and PPs greatly influence the consumer appeal of smoothies, suggesting the need to develop novel formulation and processing methods if a satisfactory functional beverage is to be developed incorporating these ingredients.
... Apple pectin in cellulose was used for preparing whey with food fibers. The chemical composition of the apple powder is presented in Table 1 [15][16][17][18]. ...
Article
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The article presents fixation methods of parameters of whey with food fibers for fermentation with lacto-fermentative Zygosaccharomyces lactis 868-K yeast for getting a non-alcoholic fermented beverage. As a result of the analysis of conditions of preparation and introduction of food fibers – apple pectin in cellulose and orange Citri-Fi into whey, there were determined optimal parameters of the process of increasing viscosity of whey-vegetable mixtures. The method of IR-spectroscopy fixed the influence of different forms of bonds of food fibers’ moisture in mixtures with water and whey. There was revealed the continuous absorption of moisture of spectrums of samples with food fibers and apple pectin in cellulose in strips of 2668 and 2723 cm-1, that testifies to the presence of strong hydrogenous bonds and high concentration of a mobile proton and, as a result, the high sorption ability to water. There were offered methods and gotten results of the analysis of the carbon dioxide content, amount of formed ethyl alcohol and yeast cells, allowing to determine rational conditions of fermentation of whey-vegetable wort of the increased viscosity. At fermentation using Zygosaccharomyces lactis 868-K race, the most intensive increment of yeast cells was observed before 30 hours of fermentation. There was established the rational temperature of fermentation of whey-vegetable wort with the increased viscosity– 30...32 °С, at which the maximal accumulation of yeast cells - 70,5...71,2 мmln/cm3 and ethyl alcohol 0,69...1,02 % was observed. The presented information was enough for grounding parameters of technological stages of whey fermented beverages with the high viscosity.
... Dietary fiber hydrolyzed by endogenous enzymes in the small intestine of human beings is considered an important nutrient for health [14]. Dietary fiber includes a mixture of plant carbohydrate polymers (cellulose, hemicelluloses, pectic substances, gums, resistant starch, inulin, lignin and, other non-carbohydrate components; polyphenols, waxes, saponins, cutin, phytates, resistant protein) [15]. ...
Article
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Objective: The aim of this study is to determine hazelnut testa which is a good example of agro-food by-products as a potential source of natural antioxidants and functional food ingredients. Material and Method: Ultrasound assisted extraction (UAE) was used for less analysis time in both determination of dietary fiber and the phenolic compounds. The total dietary fiber contents were determined using both the Association of Analytical Chemistry (AOAC) methods and the enzymatic-chemical method. Result and Discussion: The results presented that hazelnut testa had a relatively high phenolic content both the extract obtained by CE (1413.32 mg gallic acid equivalent (GAE)/g dry matter) and UAE in 5 min (1420.86 mg GAE/g dry matter). The extract obtained by UAE possessed higher antioxidant activity than the extract obtained by CE in both antioxidant activity methods. Three phenolic compounds identified in the extract obtained by CE while four phenolic compounds found in the extract obtained by UAE. In the enzymatic-chemical method, the dietary fiber in the extract obtained by CE contained 68.93% while the extract obtained by UAE was 70.69%. Our results suggested that hazelnut testa can be used in the preparation of low calorie, high fiber, and antioxidant-rich foods, food supplements, and active pharmaceutical ingredients.
... These high molecular weight substances are generally recognised to be safe since these do not pass the gastro-intestinal tract and are not further taken into consideration. However, considering the manufacturing process of the NSEs, these polysaccharides may depolymerise into smaller sugar molecules, which was reportedly demonstrated in apples (Colin-Henrion et al., 2009). This depolymerisation process is monitored by the derivatisation GC-MS technique described above and substances are assessed in step 4 of CoMSAS (see further). ...
... Recently, Santiago et al. observed an increased leaching of proteins, monosaccharides and other pectin-associated sugars from carrot fibres by a combined mechanical (HPH) and thermal treatment [43]. A co-precipitation of sugars and proteins leached from mechanically and thermally treated apple fibre might have a major impact on the composition of AIS as shown by [44]. Most likely in our experiments, other associated plant-based components such as sugars and proteins might also leach from orange fibre and were incorporated into the gel-like AIS during precipitation. ...
Article
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Mechanical and thermal processings may affect the composition and the techno-functional properties of dietary fibre as a part of a complex food system. The aim of this study was to investigate the impact of a mechanical and thermal treatment alone or in combination on alcohol insoluble substance (AIS), the content of galacturonic acid (GalA), the water retention capacity (WRC) and the microstructure by scanning electron microscopy (SEM). Two samples of orange fibre with different particle size (coarse and fine) were investigated in an experimental design and evaluated with regard to particle size (d50) after treatment and their impact on network formation. Our study highlights a more pronounced susceptibility of the coarse fibre towards mechanical stress compared to the fine fibre with regard to particle size reduction. High-pressure homogenization (HPH) represents the crucial step regarding AIS release and the increase of WRC for both fibres. A mechanical treatment with additional thermal treatment maximises AIS release. GalA, as a marker for pectin in AIS, was detected in various amounts depending on the intensity of the treatment. Highest values for WRC were achieved for the coarse fibre as a consequence of both, particle size reduction and the formation of a stable network on a microstructural level.
... Apple sauce is mainly used as snacks, it can also be used as a functional alternative to chocolate. It is also used as between-meal food particularly by children (Colin-Henrion et al., 2009). Besides being a rich source of nutrients, these sauces must be acceptable to the consumers from the sensory point of view. ...
... Apple sauce is mainly used as snacks, it can also be used as a functional alternative to chocolate. It is also used as between-meal food particularly by children (Colin-Henrion et al., 2009). Besides being a rich source of nutrients, these sauces must be acceptable to the consumers from the sensory point of view. ...
Article
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Abstract The present investigation was undertaken to develop sauce from different cultivars of apples. Apple sauce of 5 cultivars was developed and effect of the storage conditions on the pH, acidity, TSS, total sugar, color, sensory, and rheological behavior of different apple sauce cultivars was studied. Analytical determinations were made after 0, 15, 30, and 45 days at both refrigerated and ambient conditions. The observed range of TSS was 30 to 30.14˚brix for refrigerated and 27.4 to 30.7˚brix for sauces stored at ambient storage conditions.. The pH decreased during the overall storage period from 4.07 to 3.96 in refrigerated samples, while as pH decreased from 4.06 to 3.92 in ambient stored samples. Rheological properties of sauces were evaluated using a parallel plate rheometer that showed the storage modulus, Gʹ higher than the loss modulus, G″ for all the sauce samples indicating the dominance of the elastic behavior. The viscosity decreased with an increase in the shear rate for both, refrigerated and ambient stored sauce samples at the end of the storage period. Organoleptic characteristics (taste, color, aroma, and appearance) were examined by a semi‐trained panelist using 5 point hedonic scale. The sauce samples from Mollies Delicious and Chamure apple cultivars showed the highest acceptance.
... Apart from polyphenols, the polysaccharides obtained in unripe fruits also showed antioxidant and scavenging effects of free radicals, which may prevent and treat some chronic diseases [51,52]. To study the mechanical structure of plant cell walls, MacDougall et al. [53] used a gelation technique and found that pectin polysaccharides were the main component of cell walls. ...
Article
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Fruit thinning is a cultivation technique that is widely applied in horticulture in order to obtain high-quality horticultural crops. This practice results in the discarding of a large number of thinned unripe fruits in orchards each year, which produces a great waste of agricultural resources and causes soil pollution that may be an important reservoir for pest and plant diseases. Current studies showed that bioactive compounds such as polyphenols, organic acids, monosaccharides and starches are present in unripe fruits. Therefore, we reviewed the bioactive components obtained from thinned unripe fruits, their revalorization for the food industry, their beneficial effects for human health and the methods for obtaining these components. We also performed a calculation of the costs and benefits of obtaining these bioactive compounds, and we proposed future research directions. This review provides a reference for the effective utilization and industrial development of thinned unripe fruits obtained from horticultural crops. Furthermore, revalorizing the waste from this cultural practice may increase the economic benefits and relieve the environmental stress.
... In addition, HMFs had higher fiber content as compared to CIFs in our study. This might be explained by the industrial process (heat treatment and mechanical process) where a portion of fiber is likely be lost [56,57]. It is important for manufacturers to optimize the recipe's design and the industrial process for achieving higher contents of fiber in CIFs. ...
Article
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Complementary feeding (CF) is an important determinant of early and later life nutrition with great implications for the health status and the development of an adequate growth. Parents can choose between homemade foods (HMFs) and/or commercial infant foods (CIFs). There is no consistent evidence as to whether HMFs provide a better nutritional profile and variety over CIFs. The aim of this study was to compare the nutritional profiles and food variety of HMFs versus CIFs in the Spanish market targeted for infants (6–11 months) and young children (12–18 months). Thirty mothers with their children aged 6 to 18 months were included in this cross-sectional study, following a 3-day weighed food diary of which HMFs were collected and chemically analyzed. HMFs meals for infant provided significantly lower energy, higher protein and higher fiber, for young children provided significantly higher protein and fiber than CIFs meals. HMFs fruit purees for infant shown significantly higher fiber and for young children provided higher energy than CIFs. HMFs meals contained a significantly greater number of different vegetables than CIFs meals (3.7 vs. 3.3), with carrot as the most frequently used in both. However, in CIFs fruit purees shown higher different fruits than HMFs, in both the banana was the fruit most frequently used. There was a predominance of meat and lack of oily fish and legumes in both HMFs and CIFs meals. HMFs and CIFs were equally characterized by a soft texture and yellow-orange colours. Importantly, our findings emphasize the need for clear guidelines for the preparation of HMFs as well as the promotion of food variety (taste and textures) in both HMFs and CIFs to suit infants’ and young children’s nutritional and developmental needs.
... There are several studies on the effect of thermal processing on quality changes of fruits and vegetables such as shelf life, texture, enzymes, colour and bioactive components (Awuah et al. 2007;Benlloch-Tinoco et al. 2014;Houben et al. 2014;Moelants et al. 2013;Shinwari and Rao 2018;Tola and Ramaswamy 2014). Production of dietary fibre ingredient from fruit and vegetable by-products has also been studied by other researchers (Colin-Henrion et al. 2009;Garcia-Amezquita et al. 2018;López-Marcos et al. 2015). However, in these studies kinetics of chemical reactions which are taking place in the cell wall of the biomass material have not been studied. ...
Article
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The kinetics of pectin reactions in apple pomace were modelled preparatory to developing a time-temperature operating map for quantity and quality of solubilized pectin and other reactions in apple pomace. This graph can be used for selecting suitable time-temperature conditions for hydrothermal treatments to ensure a safe product with expected quality. Kinetics were measured for the major reactions in apple pomace heated at 90–140 °C for 0–210 min, in particular for the solubilization and depolymerization reactions of pectin. Maximum levels of soluble pectin (~ 605 μmol galacturonic acid/g dry pomace) were observed when heating pomace (diluted 1:2) at 130 and 140 °C for 15 and 7 min, respectively. Acid hydrolysis and β-elimination reactions showed temperature-dependent behaviour, with activation energies of 81 and 65 kJ/mol, respectively. Heating at temperatures ≥ 110 °C resulted in degradation of soluble pectin into ethanol-soluble galacturonic acid. Depolymerization reactions of pectin occurred at non-esterified sites within the pectin polymers, as suggested by the high degree of esterification of the remaining insoluble pectin.
... Henicus whellani is processed using various methods such as roasting and boiling before consumption. Processing operations may play a role in determining the fibre content and the type of fibre remaining in the final product (Colin-Henrion et al. 2009). ...
Article
Globally, edible insects are increasingly being recognised as an alternative to animal protein source. However, the effect of heat-processing methods on the insects’ nutritional value has not been extensively studied for most edible insects. The effect of thermal processing on proximate and dietary fibre composition of the edible ground cricket, Henicus whellani Chopard, was investigated at different exposure periods for roasting and wet-heating (0, 15, 30 and 60 min); and for microwaving (2 and 5 min). Moisture, ash, crude fat and crude protein were determined using standard proximate analysis methods whilst dietary fibre fractions were determined using the enzymatic gravimetric method. Highest crude protein content (67.6%) was observed after microwaving for 5 min. Crude fat was highest (10.7%) after wet-heating at 95 °C for 60 min. The highest ash content (5.1%) was attained after wet-heating at 95 °C for 30 min. All thermal processes resulted in significant increase in soluble dietary fibre fractions. The highest soluble dietary fibre (5.78 g/100 g) was obtained after roasting for 60 min at 60 °C. Roasting at a lower temperature for shorter time (60 °C for 15 min) resulted in higher insoluble dietary fibre (8.70 g/100 g) than at a higher temperature and longer time (80 °C for 30 min)(3.72 g/100 g). The highest total dietary fibre (13.81 g/100 g) was obtained after roasting for 60 min at 60 °C while the lowest fibre level (4.66 g/100 g) was obtained after roasting for 30 min at 80 °C. Microwaving (for 5 min), wet-heating (95 °C for 60 min), wet-heating (95 °C for 30 min) and roasting (60 °C for 60 min) resulted in the highest retention of protein, fat, ash and total dietary fibre; respectively. The evaluated time-temperature combinations are recommended for insect processing to achieve protein, fat, ash and dietary fibre fractions suitable for human consumption.
... Moreover, on quantitative considerations , lignins, as well as high methoxy pectins (HMP), which also show high 1-MCP sorption in vitro ( ), cannot explain consumption of 1-MCP by CFH. Based on total pectin (Billy et al., 2008) and fiber (including lignin) (Colin-Henrion et al., 2009) contents of apple fruit, the tissue equivalents (5 g fresh weight) used in standard assays for 1-MCP metabolism would have contained a maximum of about 35 mg of galacturonic acid and 116 mg of dietary fiber. Filtration or centrifugation (15,000 × g) during CFH preparation would have removed the bulk of insoluble fiber including lignins, and only about 5–11% of apple cell wall pectins are readily soluble without harsher extraction procedures (chelators, high temperature) (Lo Scalzo et al., 2005). ...
Article
Non-specific sorption of 1-MCP has been demonstrated for a number of fruit and vegetable tissues. In experiments examining comparative sorption of 1-MCP gas (765μmolm−3, 18.2μLL−1) to whole and processed apple fruit, sorption rate increased from 3.0±0.2ngkg−1s−1 in intact fruit to 13.8±2.4 and 28.2±1.5ngkg−1s−1 in halved and fresh-cut wedges, respectively. Sharply enhanced sorption was also observed in whole fruit in response to peeling, indicating that sorption was restricted by epidermal tissue and/or enhanced in response to tissue wounding. Sorption to fresh-cut apple was reduced nearly 90% in response to tissue heating. Heat inactivation of 1-MCP sorption was not a consequence of cellular disruption, as frozen–thawed tissue retained around 76% of initial sorption rate and 95% of sorption capacity over 6h. High 1-MCP sorption was also exhibited by asparagus spears. Sorption rate and capacity of asparagus spears were unaffected by tissue wounding and were inhibited 54 and 50%, respectively, following a freeze–thaw cycle. As with apple tissue, sorption of 1-MCP to asparagus tissue was inactivated (>90%) following tissue heating. The strong inhibition by heating indicated that metabolism participates in tissue 1-MCP consumption. Subsequent analysis revealed that cell-free homogenates (CFH) from apple fruit tissue metabolized 1-MCP at rates approaching 80ngkg−1s−1. Activity was negligible in buffer-insoluble residue (BIR). Standard 1-MCP metabolism assays utilized 10mL CFH from 5.0g of tissue along with 10mL 125molm−3 Na-MES, pH 5.0. The solutions were sealed in 244mL jars and provided with 420.5μmolm−3 (10μLL−1) gaseous 1-MCP (SmartFresh™ Technology). 1-MCP metabolism in apple CFH displayed saturation kinetics, with a Km of 160mmolm−3 and Vmax of 4.12μmolkg−1s−1, occurred optimally at pH 5, and was inhibited by heating (>90%), ascorbate (83% at 4molm−3), hypoxia (45% at 0.25kPa O2), and sodium docecyl sulfate (SDS, 63% at 34molm−3). 1-MCP metabolism was also detected in CFH from plantain peel but not pulp, consistent with the high and low sorption capacities of the respective tissues. High sorptive properties of asparagus spears were not evident in CFH, which showed no detectable 1-MCP metabolism. CFH from asparagus reduced 1-MCP metabolism in apple fruit CFH by 75%, providing evidence for compounds in asparagus that inhibited 1-MCP metabolism. The data suggest that membrane-associated, enzymic oxidation rather than physical sorption constitutes the primary sink for 1-MCP applied to fruit and vegetable tissues.
... Table 2). That could be due to the loss of insoluble fibers in the removed particle fraction (Colin-Henrion, Mehinagic, Renard, Richomme, & Jourjon, 2009) ...
... al., 2010;Virlet et al., 2014). La pomme est une source d'antioxydants et de fibres alimentaires à faible teneur en calories qui permet une réduction du risque de maladies Introduction générale 14 cardiovasculaires, de cancer et d'asthme ( Eberhardt et al., 2000 ;Colin­ Henrion, 2008). La consommation régulière de pommes (2 à 3 par jour) pourrait en effet diminuer de 5 à 15 % le taux de cholestérol (Aprifel, 2008). ...
Thesis
Dans le contexte des plans Ecophyto, il est primordial de trouver des alternatives aux traitements phytosanitaires. La lutte biologique par conservation fait partie de ces alternatives et, dans ce cadre, nous nous sommes intéressés à déterminer les rôles possibles des araignées en tant que prédateurs généralistes dans les vergers de pommiers. Pour cela, trois axes de travail ont été définis : (i) d’abord étudier les facteurs locaux (protection phytosanitaire et environnement des vergers) expliquant l’abondance et la diversité des communautés d’araignées; (ii) ensuite déterminer si les araignées sont actives en hiver dans les vergers dans le but d’estimer leur rôle sur les stades hivernants de ravageurs; (iii) et enfin étudier la faisabilité et l’efficacité d’un lâcher d’araignées contre le carpocapse des pommes. Dans le premier axe, nous avons mis en évidence des effets significatifs (abondance, diversité, composition) entre les communautés d’araignées issues des vergers en AB et celles issues des vergers PFI, par contre les effets de l’environnement proche des vergers (haies et parcelles alentour) ne semblent pas prépondérants. Dans le second axe, nous avons démontré que dans les vergers du Sud-est de la France, on trouve des araignées actives même au cœur de l’hiver, les plus abondantes furent les Philodromus sp, les Trachelas sp. et les Clubiona sp. Enfin dans le dernier axe, nous avons montré qu’il était possible de transférer et lâcher des araignées d’intérêt (C. mildei et C. leucapsis) et que l’abondance du carpocapse diminuait quand celle de C. mildei augmentait à l’échelle de l’arbre, au moins la première année après le lâcher. L’ensemble de ces résultats permet de poser les bases d’une gestion active des communautés d’araignée en vue d’augmenter leur contribution à la lutte biologique en verger.
... In an apple tissue, pectolytic enzymes cause its maceration, cell lysis, modifi cation of cell wall structures and depolymerisation [Kabbert et al., 1997], thus changing the overall fi bre structure of the pomace. In fresh apples, the soluble fi bre fraction, mainly pectins, represents around 50-30% of the overall fi bre content [Suni et al., 2000;Colin--Henrion et al., 2009], whereas apple pomace consists mainly of the insoluble fi bre (about 83%) [Dongowski et al., 2002]. Numerous articles describe the benefi cial effect of apple fi bre consumption and its favourable effects on such diet-related diseases as obesity, diabetes, cardiovascular disease and cancer [Hyson, 2011]. ...
Article
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The aim of this study was to scrutinise if the dietary addition of a low-pectin fibre preparation obtained from apple pomace, the by-product of apple concentrate processing, is able to favourably affect the gut metabolism, antioxidant status and blood bio-markers of the organism, as it takes place when apple fibre is present in the diet as an unprocessed ingredient. The nutritional experiment was performed on rats allocated to 2 groups of 10 animals each and fed for 2 weeks with either a control cellulose-containing diet or an experimental low-pectin apple fibre-containing diet. To induce metabolic disorders a diet rich in saturated fat and fructose was used in both diet-specific groups. The dietary apple fibre preparation (AFP) significantly reduced the activity of sucrase and maltase in the mucosa of the small intestine. In the caecal digesta, the dietary AFP significantly increased bacterial α-glucosidase and α-galactosidase activity, whereas bacterial β-glucuronidase activity was significantly reduced. Also, the content of short chain fatty acids in the caecal digesta was significantly increased after the AFP supplementation. In the blood serum, the dietary AFP significantly reduced the glucose concentration, and decreased the ratio of total cholesterol to HDL cholesterol. In conclusion, the tested dietary AFP is still able to favourably affect the gut metabolism and can also ameliorate blood glucose concentration, which seems to be related to the inhibition of mucosal disaccharidase activities. However, the analysed preparation has no influence on the antioxidant status of the organism and may trigger adverse effects on cholesterol metabolism.
Article
Water-soluble apple peel polysaccharides (APP) and apple flesh polysaccharides (AFP) were isolated from Pink Lady fruits, and their in vitro antioxidant capacities were characterised by DPPH(), HO(), and O(2)(-) systems, and ferric-reducing antioxidant power assay. Oral administration of APP at 250 and 500mg/kg bw in mice was shown to be as effective as AFP in lowering the CCl(4)-caused increases of serum alanine aminotransferase, aspartate aminotransferase and lactic dehydrogenase activities, and hepatic malondialdehyde level, and antagonising the decreases in antioxidant superoxide dismutase and glutathione peroxidase activities caused by CCl(4) (p<0.05). Histopathological examinations further confirmed that both APP and AFP could protect the liver from CCl(4)-induced histological alteration. HPLC analysis also showed similar profiles of monosaccharide composition for APP and AFP with arabinose, galactose and galacturonic acid being main component monosaccharides. All of these findings demonstrate that the extracts of both APP and AFP possess antioxidant and hepatoprotective potential.
Article
We studied the effect of variety, ripening and processing parameters on applesauce rheology. Four varieties at 3 ripening stages were processed into applesauce. Apples were diced, heated to 85 °C for hot break process (no heating for cold break), fed to a turbo extractor (400–1800 rpm) and hot-packed. Samples were analyzed for rheological and physico-chemical properties. Results were analyzed by ANOVA and Tukey’s test (p ⩽ 0.05). Variety, ripening, heating and extractor speed, significantly affected sauce properties. Increasing speed produced thicker sauce. Ripening improved consistency for Crispin and Cortland cold break sauces. Hot break produced consistent quality sauce over time with 60–100% less syneresis, 4–10% higher pectin, 20–45% smaller mean particle diameter, and 30–70% higher distribution span than cold break; thus, it could overcome variations in consistency from variety and ripening. Consistency and free-liquid flow could be predicted as functions of particle size, pectin content and pectin degree of methoxylation (R2 = 0.80, 0.93).
Article
The adsorption isotherms (20°C) and the relationship between water content and glass transition temperature were modeled in freeze-dried strawberry powder studying the effect of the addition of maltodextrin and arabic gum. Both compositional and physicochemical analyses of strawberry pulp were performed. If the midpoint of the glass transition is considered, the critical water activity that ensures the glassy state of the product during storage at 20°C increased from 0.094 to 0.237–0.341 when maltodextrin and arabic gum were added, respectively. The increase in the critical water content was not so marked and it was noticeable only in arabic gum added sample (from 7.5 to 8.9g water/100g product), being this sample more stable.
Article
The adsorption isotherms (20°C) and the relationship between water content and glass transition temperatures were modeled in freeze-dried borojó powder studying the effect of the addition of two maltodextrins with different dextrose equivalent (DE). Both compositional and physicochemical analyses of borojó pulp were performed. At room temperature (20°C), the critical water content that ensures the glassy state of the product during storage increased from 5.9gwater/100gproduct to 8.5–9.1gwater/100gproduct when maltodextrins were added, without there being any significant differences related to the different DE. The critical water activity also increased from 0.285 to 0.504–0.510, being the borojó powder with maltodextrins added more stable.
Article
Intakes of apple and its products are shown to reduce the risk of coronary heart disease (CHD) by delaying occlusion of coronary arteries. In our previous study, we showed that apple pectin protected against myocardial injury by prohibiting apoptotic cascades in a rat model of ischemia/reperfusion. Thus, we hypothesized that water-extracted apple, into which apple pectin was released from the cell wall, might exhibit the same efficacy as apple pectin. To test this hypothesis, we fed rats either cold- (CWEA) (400 mg/kg/day) or hot-water-extracted apples (HWEA) (40, 100, and 400 mg/kg/day). Three days later, the rats were subjected to myocardial injuries by ligating the left anterior descending coronary artery (30 min), and subsequently, the heart (3 hr) reperfused by releasing the ligation. Only the rats that were supplemented with HWEA (400 mg/kg/day) showed significant reductions in infarct size (IS), which was 28.5% smaller than that of the control group. This IS reduction could be partly attributed to the prevention of steps leading to apoptosis. These steps are manifested by a higher Bcl-2/Bax ratio, lower procaspase-3 conversion to caspase-3, and inhibition of DNA nick generation, which reflects the extent of apoptosis. The findings indicate that HWEA supplementation reduces myocardial injury by inhibiting apoptosis under ischemia/reperfusion conditions. In conclusion, this study suggests that apple intake, specifically boiled apple, might reduce the risk of CHD by inhibiting post-occlusion steps, such as myocardial injury after artery occlusion, as well as pre-occlusion steps, such as atherosclerotic plaque formation.
Article
Grifola frondosa (G. frondosa) is widely known for its anti-tumor potential, which has been demonstrated by numerous scientific researches. In this study, two water soluble polysaccharide-protein complexes were extracted from G. frondosa at 4 °C (GFG-4) and 100 °C (GFG-100) and purified. Compared with GFG-100, GFG-4 had a higher protein content and molecular weight. The main monosaccharides of GFG-4 and GFG-100 were rhamnose, glucose, and galactose, with an approximate ratio of 3.00: 1.00: 0.86 and 2.85: 1.00: 0.94, respectively. The Fourier transform infrared spectra indicated that the two polysaccharide-protein complexes displayed characteristic functional groups of polysaccharides and proteins, and mainly contain pyranose ring with α-glycosidic linkage. Atomic force microscope images showed that both GFG-4 and GFG-100 exhibited straight chains, and GFG-4 possessed a relatively abundant fraction of branched chains. Intriguingly, GFG-4 showed a stronger antiproliferative activity against HepG2 cells than GFG-100. The mechanisms were further investigated by quantitative real-time PCR and western blot, it found that GFG-4 inhibited the proliferation of HepG2 cells mainly through the intrinsic activation of mitochondrial pathway and the Fas/FasL-mediated Caspase-8/-3 pathway. Conclusively, G. frondosa cold-water extracted polysaccharide-protein complexes could be used as a functional food for preventing or treating hepatocellular carcinoma.
Chapter
This chapter discusses health benefits of the fibre in fruit. Much of the fibre that we ingest when we consume fruit comes from the walls of the parenchyma cells in the tissues of the luscious fleshy forms but not exclusively as, botanically, a fruit can take many forms. Each cell in a plant is surrounded by a wall. New walls are formed at the end of cell division at a specialized region in the cytoplasm known as the phragmoplast. When fully formed, plant cell walls contain an array of complex polysaccharides, including cellulose, pectic polysaccharides, xyloglucans, heteroxylans and galactoglucomannans that can differ in their fine structure and relative proportion among species, and undergo subtle structural changes during development, storage, and cooking. When planning experiments to determine the health benefits of fibre and other food components, one should be aware of these chemical differences so that outcomes can be causally related.
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The aim of this thesis is to evaluate the ability of several apple cultivars for industrial processing. Three main objectives have guided this study. The first objective was to identify among ten varieties of apples, which ones were the most suited for two types of industrial processing: vacuum cooking and apple cubes. This selection was done by the analysis of the mechanical properties of the fruits before and after processing. Finally, five different cultivars were selected for each type of process. The second objective was to assess the impact of postharvest storage and the duration of thermal treatments applied during processing, on the mechanical, sensory and biochemical markers related to the evolution of the texture of the products. The physical and sensory characterization confirmed the strong impact of fruit genotype on the final quality of the products. Analysis of cell wall polysaccharides indicated a solubilization of pectic compounds related to the postharvest storage and the cooking of the apples. The third objective was to monitor of the evolution of some polyphenols and their activity, depending on the variety, and during industrial processing. Overall, vacuum cooking preserved these compounds. In contrast, during the « apples cubes » process, degradation was observed.
Article
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Pomace produced during the apple juice production is composed mainly of cell wall polysaccharides, which constitute a dietary fibre. Since those compounds can be cross-linked with some divalent metal ions according to an egg-box model, they cause the viscosity of aqueous solutions to significantly increase. The apple pomace analyzed was physically and chemically transformed in order to obtain an MPSN polysaccharide matrix. The objective of the research study was to determine the ability of MPSN polysaccharide matrix to cross-link by means of the divalent metal cations of Ca2+, Mg2+, and Fe2+. On the basis of the increase in the apparent viscosity of the solutions analyzed, it was found that each ion applied had the cross-linking ability; however, the greatest degree of cross-linking was obtained by the Ca2+ and Fe2+ ions. The flow curves of MPSN matrix were described by an Ostwald de Waele’s model. The MPSN solutions with calcium ions added at 12 and 15 mM concentration rates were characterized by the lowest flow behaviour indices and, thus, by the highest pseudoplasticity degree. In all the analyzed samples, a thixotropy phenomenon occurred: in the case of Ca2+ and Fe2, this phenomenon depended on their concentration rate. This fact proves their ability to regenerate structure during relaxation.
Article
Fruit purees are considered as concentrated dispersions of deformable and insoluble particles in a continuous phase or serum rich in water, sugar and soluble pectin. The dispersed phase consists of cells or cell clusters of parenchyma tissue and the insoluble cell wall material dispersed in the serum represents a very low weight (~ 1% w/w). The structure and the rheological properties of purees will depend on many internal factors such as the variety and ripeness of the fruit and external factors occurring during the processing (mechanical and thermal treatment). Texture is a key quality attribute of purees and thus constitutes an important potential source for new product development. The main objective of this study was to better understand the relationship between the rheological, structural and sensory properties of apple puree, in order to pilot and control the texture of the products. The study was performed with a single batch of apple puree prepared industrially from fresh mature Golden Delicious. In order to create purees with varied structure and texture, three structural parameters were identified and modified: the cell walls concentration (related to the amount of pulp), the particle size and the viscosity of the continuous phase. A separation-reconstitution strategy joined to a grinding step and the modification of the serum viscosity allowed us to obtain a wide range of products with different structures and textures. The construction of two experimental designs made it possible the controlled preparation of the products so as to study the relatioins between structure, rheology and texture of the apple puree. Physical and sensory characterization highlighted the importance of structural parameters on the rheological behaviour and perception of the texture of the puree. Thus, the concentration of particles is the main parameter influencing these properties, followed by the particle size and the serum viscosity. The increase in particle content translates directly at the "overcrowding" that also depends on the particle size. Mechanical treatment leads to the separation of clusters of parenchyma cells in to individual cells; this change in structure involves marked changes of properties. Rheological and structural characterization made it possible the generation of rheological models and the better understanding of the behaviour, the state and the role of particles (soft and deformable) on the structure of the medium and the volume occupied by them. This approach has been completed and validated by the observation of dispersions by various microscopic techniques. The different regimes of concentration were identified. Texture perception of apple puree can be described basically by their "consistency" and their "graininess". The viscosity of the continuous phase has an impact on the perception of "graininess" and in the cohesion of the particle network. Our results show that the texture of plant food dispersions can be "mastered" by controlling a few selected key parameters: the concentration of cell walls (pulp) and particle size, completed by the viscosity of the continuous phase. High possibilities for innovation are opened by playing on these parameters that can be modified during the processing.
Thesis
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The present research evaluated the effect of the partial substitution of wheat flour for powder of apple and mandarin pomace in the bread elaboration, and the main aim was increase the content of dietary fiber of the product, in addition of giving added value to the wastes produced by the industry of two of the most commercialized fruits in the country. The powder of apple pomace, which had 43,9% of dietary fiber on dry basis and 12,3% of moisture, was elaborated from the wastes of the production of Delicia apple pulp. The powder of mandarin pomace, which had 43,8% of dietary fibre on dry basis and 12,6% of moisture, was elaborated from the wastes of the production of Malvacea mandarin clusters. These products were mixed with the bread mass, and based in sensory (flavor, odor and color), and physic (specific volume and effort required for deformation) analysis, the ideal percent of partial substitution was determinated, which was 10% for apple and 5% for mandarin. The breads elaborated with the powder of apple and mandarin pomace with the best attributes had a increase of 88,3% and 25,0% of dietary fibre, respectively. Keywords: Dietary fiber, by-products, Malus domestica, Citrus reticulata, bread, parcial substitution of wheat flour.
Article
膳食纤维指抗人体小肠消化吸收,但在大肠中能部分或全部发酵的可食用植物性成分——碳水化合物及类似物质,包括纤维素、半纤维素、木质素、果胶、抗性淀粉、寡糖等,按溶解性分为可溶性膳食纤维和不溶性膳食纤维两类。本文综述了“高纤维”、“纤维源”果品及高品质膳食纤维,从寡糖、抗性淀粉及细胞壁组分等方面综述了果实膳食纤维组成的研究进展,并进一步挖掘了果实总膳食纤维、可溶性膳食纤维和不溶性膳食纤维的单糖组成。 Dietary fibre means carbohydrate polymers which are not hydrolyzed by the endogenous enzymes in the small intestine of humans, including cellulose, hemicellulose, lignin, pectin, resistant starch and oligosaccharide, which was divided into two types as soluble dietary fiber and insoluble dietary fiber according to the solubility. This article summarizes the “high fiber”, “fiber source” fruit and high quality dietary fiber. The research progress of dietary fiber composition in fruits was reviewed from the aspects of oligosaccharides, resistant starch and cell wall component. The monosaccharide composition of total dietary fiber, soluble dietary fiber and insoluble dietary fiber was also reviewed.
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Lipid digestibility and bioaccessibility (i.e. solubilization) may be impacted by various factors. For example, dietary fibres may interact with lipids and other digestive molecules during gastrointestinal digestion, and gastric pH may impact lipid droplet microstructure. Thus, these parameters may have implications for the release and uptake of bioactive fatty acids such as DHA. This study investigated how apple pectin (0.00, 5.68, or 100.00 mg/5.0 g emulsion), combined with variable gastric pH (2.0, 3.0 or 4.8), impacted the in vitro digestion of a DHA-rich algal oil lecithin-stabilized emulsion (10:1.2:88.8 oil:lecithin:water, D3,2 = 0.137 ± 0.001 nm). Low gastric pH (2.0 and 3.0) induced severe emulsion destabilization. However, the addition of a low-level of pectin (5.68 mg/5.0 g emulsion) reduced the destabilization at pH 3.0. Small lipid droplets, maintained either by this low-level of pectin at pH 3.0 or by a higher gastric pH (4.8), were associated with greater early (p < 0.05), but not eventual (p > 0.05) duodenal lipolysis (pH 7.0) and higher DHA bioaccessibility (>69%, p < 0.05). Samples containing 100.00 mg pectin/5.0 g emulsion had the lowest overall lipolysis and DHA bioaccessibility across all pH values (p < 0.05). Therefore, pectin content and gastric pH interactively impacted emulsion digestion. The presence of applesauce, matched for pectin concentration, further destabilized the emulsion and limited lipid digestibility and DHA bioaccessibility, compared to the pectin-only samples. Overall, a stable emulsion microstructure during gastric digestion promoted in vitro lipid digestibility and DHA bioaccessibility.
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Blueberry composition was characterized for 6 cultivars. It contains a good amount of dietary fiber (10% to 20%) and pectin (4% to 7%) whose degree of methylation (DM) is sensitive to food processing. A low temperature blanching (LTB: 60 °C/1 h) was applied on blueberry purees to decrease pectin DM, in order to modulate puree properties and functionalities (that is, viscosity and stability), and to enhance pectin affinity toward other components within food matrices. Fiber content, viscosity, pectin solubility, DM, and monosaccharide composition were determined for both pasteurized, and LTB+pasteurized blueberry purees. The results showed that neither the amount of fiber, nor the viscosity were affected by LTB, indicating that this treatment did not result in any significant pectin depolymerization and degradation. LTB caused a decrease both in pectin DM from 58–67% to 45–47% and in the amount of water-soluble pectin fraction, the latter remaining the major fraction of total pectin at 52% to 57%. A LTB is a simple and mild process to produce blueberry purees with mostly soluble and low-methylated pectin in order to extend functionality and opportunities for interactions with other food ingredients.
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Apple by-product is an agro-food by-product mainly wasted or underutilized, which is increasing because of the demands of consumers of apple juice or cider. This fruit residue is very rich in dietary fibre, and although the major component is the insoluble dietary fraction (IDF), pectins from soluble DF (SDF) comprised mainly by homogalacturonan and rhamnogalacturonan type I branched with arabinans, galactans and arabinogalactans are remarkable. These polysaccharides are used by Bifidobacterium bifidus in vitro, producing an important amount of short chain fatty acids (SCFA), mainly acetate, as in the case of the in vivo assay with high fat diet-fed Wistar rats. Butyrate was increased 3-fold in this in vivo assay indicating that butyrate bacteria producers can use apple by-product. Thus, it showed a potential bifidogenic and butyrogenic effect that is pursued in the search of new prebiotics. Furthermore, apple by-product enriched diet increased (p < 0.05) HDL and diminished (p < 0.05) trygliceridemia and hepatic total lipids presumably because of the bile acids binding effect observed, highlighting the potential hypolipidemic effect.
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Attenuated total reflectance Fourier transform spectroscopy (ATR-FTIR) was applied on fresh (NF), freeze-dried (FD) and cell wall materials (AIS) of raw and processed apples. These samples prepared from 36 apple sets and the corresponding 72 purees, issued from different varieties, agricultural practices, storage periods and processing conditions, were used to build models including exploratory analysis, supervised classification and multivariate calibration. Fresh and freeze-dried samples presented similar fingerprint spectral variations due to processing. ATR-FTIR directly on fresh purees satisfactorily predicted textural properties such as particle average size and volume (RPD> 3.0), while freeze-drying improved assessment of chemical (RPD> 3.2) and rheological (RPD> 3.1) parameters using partial least-squares regression. The assessment of texture and macrocomponents of purees can be obtained with a limited sample preparation. For research applications because of a need of sample preparation, changes of cell wall composition during fruit processing could be assessed in relationship with pectin degradation.
Article
Procyanidins can bind cell wall material in raw product, and it could be supposed that the same mechanism of retention of procyanidins by apple cell walls takes place in cooked products. To evaluate the influence of cell wall composition and disassembly during cooking on the cell walls' capacity to interact with procyanidins, four cell wall materials differing in their protein contents and physical characteristics were prepared: cell wall with proteins, cell wall devoid of protein, and two processed cell walls differing by their drying method. Protein contents varied from 23 to 99 mg/g and surface areas from 1.26 to 3.16 m(2)/g. Apple procyanidins with an average polymerization degree of 8.7 were used. The adsorption of apple procyanidins on solid cell wall material was quantified using the Langmuir isotherm formulation. The protein contents in cell wall material had no effect on procyanidin/cell wall interactions, whereas modification of the cell wall material by boiling, which reduces pectin content, and drying decreased the apparent affinity and increased the apparent saturation levels when constants were expressed relative to cell wall weight. However, boiling and drying increased apparent saturation levels and had no effect on apparent affinity when the same data were expressed per surface units. Isothermal titration calorimetry indicated strong affinity (K(a) = 1.4 × 10(4) M(-1)) between pectins solubilized by boiling and procyanidins. This study higllights the impact of highly methylated pectins and drying, that is, composition and structure of cell wall in the cell wall/procyanidin interactions.
Article
Full-text available
Apple fibres from the tissue of three zones, namely epidermis, parenchyma and carpels zones, were prepared as nonoxidized and freeze-dried water-insoluble solid (WIS), oxidized and freeze-dried WIS, oxidized and oven-dried WIS, and nonoxidized and solvent-dried alcohol-insoluble solid. The yield and composition of the fibres, the characteristics of their soluble fraction, the enzymatic solubilization of the fibres and their hydration capacities were analysed. Oxidation led to a decrease in the amount of buffer-soluble pectin and to an increase of its hydrodynamic volume. It also decreased susceptibility to enzymatic solubilization and hydration capacities. Oven-drying, simulating industrial conditions, produced an important decrease of swelling capacity and enzymatic hydrolysis. Preparation of alcohol-insoluble solid led to higher fibre yield in all tissue zones but did not alter their properties.
Article
Changes in the carrot cell wall polysaccharides were studied after heat treatment. Blanching (10 min at 90°C) did not solubilize cell wall polysaccharides but altered the pectin structure and the protopectin fraction decreased by 25%. The enzymatic degradation of carrot was not improved by a heat pretreatment (30 min at 98°C), in comparison with blanching, but the depolymerization of the cell wall polysaccharides, particularly the pectic substances, was more extensive. The presence of cellulases was necessary for a complete liquefaction of the tissues and thus facilitated the hydrolysis of the pectic polysaccharides by pectinases.
Article
Pectic fractions, extracted with the chelating agent trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (CDTA) and with dilute sodium carbonate solutions from the alcohol-insoluble residues (AIR), were investigated by methylation analyses. To characterise structural changes related to growth and ripening, pectic fractions of unripe, mature and stored apples were analysed. Pectic fractions isolated from unripe and mature apples contained various amounts of starch. Therefore an amyloglucosidase treatment followed by a dialysis was carried out prior to further analyses. Linkage analyses were performed after a twofold reduction of uronic acids to the corresponding neutral sugar residues with NaBD4. Results of neutral sugar and uronic acid determinations revealed a loss of galactose during the first part of the ripening process. The linkage patterns of the investigated pectic fractions indicated that the loss of galactose is mainly due to a decrease in linear 1,4-linked galactose residues.
Article
The dietary fibre constituents of apple, pear, orange, peach, artichoke and asparagus dietary fibre concentrates and of wheat and oat bran were measured using an enzymatic-gravimetric method. In addition, the water-holding capacity of the dietary fibre concentrates and cereals was estimated by centrifugation.Dietary fibre concentrates of fruits and greens showed a high content of total dietary fibre (35–59 g/100 g), insoluble dietary fibre (21–44 g/100 g) and soluble dietary fibre (10–14 g/100 g), referred to dry matter. The soluble fraction was found to be greater dietary fibre concentrates of fruits and greens than in wheat and oat bran (3–4 g/100 g). Measurements of water-holding capacity showed that dietary fibre concentrates of fruits and greens had a greater affinity for water than those from cereals.
Article
Apple fruit (Malus domestica Borkh. cv. Braeburn) were harvested during fruit development. The tissue was treated with phenol, acetic acid and water (PAW) to deactivate enzymes followed by α-amylase in H2O to remove starch. Water soluble polysaccharides were obtained from both fractions. The hemicelluloses were extracted from apple cell walls with 6 M NaOH. The carbohydrate composition of the cell wall fractions and the molecular weight of the hemicelluloses were determined. There was no change in the molecular weight profile of hemicellulose fractions or of xyloglucan polymers as obtained by HPLC with a size exclusion column. The cell wall changes in relation to cell expansion mechanisms are discussed.
Article
The noncellulosic glucose content, like the xylose content, of cell walls of cortex tissue of apples showed little change as the fruit ripened and the cellulosic glucose also remained constant. There was a considerable loss of galactose residues from the walls, however, whilst only a small change in arabinose was observed. The starch was rapidly hydrolysed.
Article
Cell wall materials in the form of water-insoluble solids (WIS) and water-soluble fractions (WSF) were prepared from apples stored at 4 °C for 30 weeks. During storage, the WIS content decreased whereas the WSF content remained unchanged. The total amount of polysaccharides decreased, in particular the pectic polymers which decreased by 10%. In contrast, the soluble pectic fraction increased by 40% whilst its degree of methoxylation remained constant. The arabinose and galactose content progressively declined. The enzymatic treatment of the apple tissues was more effective the longer the storage; yields correlated well with the enzyme hydrolysis of WIS. The accessibility of pectin to poly-galacturonases in apple tissues is discussed since it was higher at the end of storage, whereas the solubilisation of pectins from WIS by polygalacturonases remained constant. On the other hand, with liquefying enzymes, the yield of pectin solubilisation from apple tissues or WIS were well correlated and increased with storage time.
Article
Cell wall material in the form of an alcohol-insoluble residue (AIR) was prepared from apples during growth and maturation on the tree and at different stages of ripening during postharvest storage. The galacturonic acid, neutral sugar, starch content as well as the degree of acetylation of the AIR were determined for each stage as was the degree of methyl esterification of the pectic substances. During the first weeks of development, the AIR content of the fruit decreased; it then stayed constant until the end of storage. The galactose and arabinose content of the AIR decreased with time while the galacturonic acid content stayed almost constant. Hardly any changes were observed in the degrees of methyl esterification and acetylation. The unripe fruit contained appreciable amounts of starch whereas none could be determined shortly after harvest. The significance of the losses of arabinose and galactose residues will be examined in a further paper.
Article
Postharvest softening of apple (Malus domestica (Borkh.)) fruit is a serious problem for growers in many countries, including New Zealand. To reduce this problem considerable research has been undertaken to determine the biological causes of softening so that this process can be managed or controlled more effectively. This review describes the pattern of softening for harvested apple fruit, and how it is influenced by different preharvest, at‐harvest, and postharvest factors. Information is also given on the likely physiological and biochemical causes of apple softening, such as fruit anatomy and cell packing, modification of the cell wall and membranes, changes in cell turgor, and the role of ethylene and other growth regulators. Despite many softening studies, there is still a poor understanding of what causes firmness variation in the marketplace. Until this understanding is improved, apple producers will continue to struggle to meet market requirements for texture.
Article
Changes in the polysaccharide composition of apple fruits ripening on and off the tree were compared. Polysaccharide fractions defined by their method of extraction were analysed colorimetrically, and the monosaccharide composition of total acetone insoluble material was analysed. Neutral carbohydrate associated with pectic extractives decreased; correspondingly galactose residues were lost in detached fruit, while galactose and arabinose residues were lost in fruit on the tree. Decreases in hemicellulose were correlated with losses of wall glucan; xylose contents did not change. Soluble polyuronide increased especially in detached fruit. DEAE-cellulose chromatography showed that this polyuronide was free from neutral sugar residues. Amounts of soluble neutral polysaccharides and glycoproteins did not change during fruit ripening.
Article
Fibre composition of the following 13 apple cultivars was studied: ‘Cortland’, ‘Empire’, ‘Fuji’, ‘Golden Delicious’, ‘Gala’, ‘Granny Smith’, ‘Jonagold’, ‘Mutsu’, ‘McIntosh’, ‘Delicious’, ‘Rome’, ‘Stayman’ and ‘York’. Fruit samples from each of these cultivars were analysed for non-starch cell wall materials (NSCWM) and non-starch polysaccharides (NSP). NSCWM was further fractionated into soluble and insoluble fibre fractions. Both NSCWM and NSP content were found to be significantly influenced by cultivar. NSCWM content ranged from 19·1 g kg−1 apple flesh in ‘Fuji’ to 36·2 g kg−1 in ‘York’. Mean(±SD) NSCWM content of all the cultivars was 23·1±4·5 g kg−1. NSP content of apple flesh ranged from 13·8 g kg−1 in ‘McIntosh’ to 28·7 g kg−1 in ‘York’ with the overall mean for all cultivars being 17·9±4·2 g kg−1. Relative amount of monosaccharides found in the hydrolysates of apple fibre also varied among cultivars. The greatest difference was observed in galactose content. ©1997 SCI
Article
Apple fiber, corn fiber, oat bran and soy fiber were analyzed to study the effect of heat processing (autoclaving at 121°C/15 min, 100°C/30 min and microwave heating for 5/10 rain) on dietary fiber fractions. Samples were analyzed for insoluble (IDF), soluble (SDF), and total dietary fiber (TDF) by an enzymatic-gravimetric method. Autoclaving reduced IDF of apple fiber and TDF of apple fiber and oat bran. Microwave heating reduced TDF in apple fiber and oat bran and IDF in oat bran but increased the SDF of apple fiber. All treatments decreased the SDF in corn fiber. Effects on dietary fiber fractions depended on fiber type and processing method.
Article
Chelator-soluble pectin was isolated from carrot under mild conditions and used as a model compound for an investigation of the heat degradation mechanism of pectin in an aqueous environment. Methyl ester content was modified with minimal changes in the polymer size. At pH 6.1 the heated pectin preparation degraded primarily through β-eliminative cleavage of the chain. The higher the methyl ester content the greater the degradation. Evidences also indicated a-small amount of hydrolytic cleavage of glycosidic bonds which was not affected by the presence of the methyl ester content. De-esterification of methyl ester groups proceeded at a faster rate than the eliminative cleavage of the chain; however, under the test conditions, it did not terminate the β-elimination.
Article
Carrots were blanched using 4 time-temperature combinations. Galacturonic acid and sugar contents of pectin extracts were determined, and immunocytochemistry experiments elucidated changes in the cell membrane. Blanching decreased galacturonic acid and total sugar contents for all treatments. Carrots subjected to high-temperature short-time (HTST) blanching contained more total galacturonic acid and total sugars in pectins than carrots blanched for a long time at low temperatures (LTLT). Similar trends were observed for methylated pectin and neutral sugars. Immunocytochemistries showed separation of the 3-way junction of cell walls, and LTLT-blanched carrots showed higher levels of JIM 7-labeled pectin (1.6 × 10−4 particles/nm2) than HTST-treated carrots (5.9 × 10−5 particles/nm2).
Article
Texture degradation of fruits and vegetables during thermal processing is partly due to pectin depolymerization. In this contribution we investigate the influence of pectin properties (degree and pattern of methoxylation) and processing conditions (pH 2.0, 3.0, 5.0 and 7.0; temperatures of 80 up to 110 °C) on pectin degradation rate constants. Pectins with different degrees and patterns of methoxylation were prepared and heated, the extent of acid hydrolysis, β-elimination and demethoxylation was assayed as a function of treatment time. As the degree of methoxylation and pH decreased, β-elimination rate constants decreased while acid hydrolysis rate constants increased. Demethoxylation rate constants were minimal at pH 3.0 and increased both at lower and higher pH. Reaction rate constants were not considerably influenced by the pattern of methoxylation. All reaction rate constants increased with increasing temperature. As β-elimination rates are reduced by competing demethoxylation, both rate constants were compared. The ratio of these reaction rate constants showed no trend with pH. However, an increase in degree of methoxylation or temperature resulted in a more pronounced increase in β-elimination rate constants than in demethoxylation rate constants.
Article
The dietary fiber contents of 19 different forms of seven fruits were analyzed by two methods and compared. Fiber content measured by the AOAC method was always greater than that obtained by the Uppsala method; the two sets of fiber data were significantly different (P < 0.002). Fiber contents of different forms of oranges, peaches and plums were similar. Fiber contents of four berries (blackberries, cranberries, red respberries, strawberries) ranged from 1.0 to 7.0% fresh weight. Peeling or canning changed the uronic acid and neutral sugar contents of the soluble and insoluble fiber fractions of several fruits. Measurement of more fiber in fruits by the AOAC versus the Uppsala method is similar to the results obtained when grain products and legumes, but not vegetables, were analyzed.
Article
The aim of this work was to investigate heat-induced changes in cell wall polysaccharides of carrot in relation to texture. Discs of fresh carrot (Daucus carota cv Amstrong) tissue were subjected to cooking (100°C, 20 min), with or without a pre-cooking treatment (50°C, 30 min). Alcohol-insoluble residues were prepared from the tissues and were extracted sequentially with water, NaCl, CDTA, Na2CO3 and 0·5 M KOH to leave a residue. These were analysed for their carbohydrate compositions, their degree of methyl esterification and the molecular size of selected soluble polysaccharides. Cooking caused tissues to soften. This involved cell separation, an increase in water- and salt-soluble, high-molecular-weight pectic polysaccharides and a concomitant decrease in the pectic polymers in all wall extracts and the residue. Pre-cooking prior to cooking enhanced cell–cell adhesion and reduced the extent of softening. This was accompanied by a general reduction in the degree of methylesterification of cell-wall pectic polymers, and a decrease in the cooking-induced modification to all pectic fractions. The firming effect of pre-cooking could be reversed by extracting the precooked+cooked tissue with CDTA, a chelating agent. The role of Ca2+ cross-linked polymers and pre-cooking in the enhancement of firmness are discussed. © 1997 SCI.
Article
Pears of the cultivar Gieser Wildeman were cooked for up to 24 h and changes in polyphenol and cell wall components were monitored. The main polyphenols were flavan-3-ols (epicatechin and its procyanidin oligomers), with an average degree of polymerisation of 6, and caffeoylquinic acid. Upon cooking, flavan-3-ols were retained in the pear tissue while the hydroxycinnamic acids were partially leached into the cooking water. After 1 h of cooking, 65% of the original flavan-3-ols and 40% of the original caffeoylquinic acid were still detectable in the pear tissue; the cooking water contained only 2% of the flavan-3-ols but 24% of the caffeoylquinic acid. Cell walls represented 23 g kg−1 of the fresh pear and were composed of cellulose, pectins and xylans. The pectic fractions was degraded during cooking while xylans and cellulose were not affected. Copyright © 2004 Society of Chemical Industry
Article
Diced carrots (Daucus carota var. Nerac) were subjected to different pretreatment conditions. The pretreated carrots were subsequently thermally processed in an oil bath (100°C) and in a static retort (equivalent processes [FoΔ 6 min] at 115°C, 120°C, and 125°C). Changes in texture were analyzed as well as changes in the degree of methylation (DM) of pectin. From all the pretreatment conditions tested, high-pressure pretreated carrots (400 MPa, 60°C for 15 min) exhibited the highest resistance to texture loss. The textural properties were significantly improved when calcium infusion was combined with low-temperature blanching condition (60°C for 40 min). A significant reduction in the DM of carrot pectin was observed for all pretreatment conditions that resulted in a reduced texture loss after thermal processing. A strong negative correlation (r ≥−0.90) exists between the changes in the degree of methylation of carrot pectin and the observed changes in texture.
Article
ABSTRACT Pretreated carrot discs were thermally processed (90 °C to 110 °C) in closed containers and the resulting textural characteristics were analyzed. The pretreatment conditions used include conventional high-temperature blanching (90 °C, 4 min), low-temperature blanching (LTB = 60 °C, 40 min), LTB combined with 0.5% calcium chloride soaking, LTB combined with 2% sodium chloride soaking, high pressure pretreatment (HP = 400 MPa, 60 °C, 15 min), HP combined with 0.5% calcium chloride soaking, and control (non-pretreated sample). Alcohol insoluble residues (AIR) from the pretreated carrot discs were characterized in terms of degree of methoxylation (DM). The AIR samples were further subjected to fractionation into water-soluble pectin (WSP), chelator-soluble pectin (CSP), and sodium carbonate-soluble pectin (NSP). Heat depolymerization patterns and β-elimination kinetics were investigated on the different pectin fractions. Thermal texture degradation was strongly influenced by the pretreatment condition used and the processing temperature during subsequent thermal treatment. Pretreatment conditions that showed a significant reduction in DM exhibited decreased WSP content, reduced β-elimination, and consequently superior textural characteristics. β-elimination was markedly pronounced in the highly methoxylated WSP fractions. CSP and NSP fractions were insensitive to β-elimination. A strong correlation (r> 0.95) between thermal texture loss of carrots and β-elimination kinetics exists. Overall, the benefits of controlled pectinmethylesterase activity in carrot processing were pointed out.
Article
The dietary fibre in the fruits of 12 genotypes of Japanese quince (Chaenomeles japonica) and 1 genotype of flowering quince (Chaenomeles speciosa) were prepared using two different methods: the alcohol insoluble solid (AIS) preparation; and the Association of Official Analytical Chemists (AOAC) method for total as well as for soluble and insoluble fibre. The two methods resulted in similar but significantly different estimates. No interaction was revealed between the methods and the genotypes studied. For content of total dietary fibre, three main groups could be distinguished: a group containing a low amount of fibre (three genotypes, 28–30 g/100 g dry matter), a group containing a medium amount of fibre (nine genotypes, 30–36 g/100 g dry matter) and an isolated genotype (Chaenomeles speciosa) that contained a considerable amount of fibre (38 g/100 g dry matter). The amount and the nature of monomeric sugars in the constitutive polysaccharides of the fibres were determined after total hydrolysis of the AIS or the total dietary fibre (TDF). The fibre contained mostly pectic and cellulosic polysaccharides. Analysis of the fibre from different parts of the fruits of two genotypes showed that they differed in their proportion of constituent polysaccharides (cellulose, hemicelluloses and pectic polysaccharides).
Article
Cell-wall polysaccharides from different tissue zones, namely epidermis, the outer parenchyma, the parenchyma of the carpels zone, the carpels and the core line, were isolated as alcohol-insoluble solids (AIS), extracted with cyclohexane-diaminotetraacetic acid, then hot dilute hydrochloric acid, and analysed, then purified by ion-exchange chromatography. In both zones of parenchyma, the cell-wall material represented about 80% of the total cell-wall material from the whole fruit. The pectins from the outer parenchyma accounted for 70% of the total, whereas the carpels zone contained a large proportion of cellulose and hemicelluloses. However, there was no change in galacturonic acid concentration. The enzymatic solubilisation of tissues or AIS was higher in the parenchyma zones than in the others. Nevertheless, the depolymerisation of the soluble pectins from parenchyma zones with an endopolygalacturonase required the action of pectin methylesterase. The depolymerisation of pectins from the other zones, however, did not.
Article
The effects of apples on lipid metabolism were studied on 40 male Wistar rats adapted to semi-purified diets containing 0.3% cholesterol. In the experimental ‘apple’ diet, a part of starch (15%) was replaced by lyophilized apple (Gala variety). In the control diet, 13% of carbohydrate was replaced by a mixture of fructose/glucose/saccharose to match the sugar supply from the apples. The lipid source was corn oil and the dietary supply of vitamin E was reduced to 1/3 of the recommended value. The rats were sampled after 21 days adaptation. The fibre supply of the apple diet was notably low (about 2%); nevertheless, there was a slight but significant cholesterol-lowering effect in plasma, as well as in liver where cholesterol esters accumulate with cholesterol diets. The lipoprotein profile was markedly altered in apple-fed rats: a reduction of cholesterol in the triglyceride rich lipoprotein (TGRLP) fraction, together with a rise in the HDL fraction; hence there was a favourable effect in a cardiovascular protection perspective. This was paralleled by effects of the apple on cholesterol apparent absorption, which was markedly depressed, whereas bile acid digestive balance was unaffected. In parallel, there was a positive effect of the apple diet on parameters of oxidative stress prevention: higher FRAP plasma levels than in controls, together with a reduced MDA excretion in urine. In conclusion, the present work indicates that a moderate supply of dessert apples elicits interesting effects on lipid and peroxidation parameters.
Article
Research to evaluate some functional properties of fibre concentrates from apple and citrus fruit residues, in order to use them as potential fibre sources in the enrichment of foods, was carried out. Fiber concentrates were analysed for their proximate content (moisture, lipids, protein and ash); caloric value; dietary fibre composition and functional properties (water retention capacity – WRC, swelling capacity – SW, fat adsorption capacity – FAC and texture). All the fibre concentrates had a high content of dietary fibre (between 44.2 and 89.2 g/100 g DM), with a high proportion of IDF. Protein and lipid contents ranged between 3.12 and 8.42 and between 0.89 and 4.46 g/100 g DM, respectively. The caloric values of concentrates were low (50.8–175 kcal/100 g or 213–901 kJ/100 g). Grapefruits had the highest WRC (2.09–2.26 g water/g DM) high SW and FAC. Texture was strongly dependent on the particle size and it was increased by the heat treatment. Every concentrate studied had interesting characteristics, suggesting possible uses in the development of fibre enriched foods.
Article
Pectin breaks down rapidly by heating with buffer at pH 6.8. This degradation is dependent on the presence of the ester. The rapid decrease in viscosity and increase in reducing end groups are indicative of a splitting of glycosidic bonds within the pectin chain macromolccules. The breakdown products show an absorption maximum at 235 mμ, react with thiobarbituric acid to give a product which absorbs at 547 mμ, and on treatment with ozone give rise to the formation of oxalic acid. These observations strongly indicate the formation of an unsaturated compound by way of a trans elimination reaction which results in the removal of the H atom at C-5 and of the glycoaidic residue at C-4.
Article
Dietary fibres are consumed from cereals, fruit and vegetables, but are also added in purified form to food preparations. Different types of dietary fibres have different structures and chemical compositions, and correspondingly are of varying nutritional and technological interest. Although many studies have confirmed the nutritional benefits of dietary fibres, the results depend on the types of dietary fibres studied or on the experimental conditions used. This article also focuses on their technological properties according to their botanical origin and physical characteristics, and discusses the main appli cations of insoluble dietary fibres in the food industry.
Article
Cell wall materials were prepared from apple tissue by seven different procedures, some of which are methods in current use in laboratories. The yield, the composition and the fractionation patterns of the pectin content, following sequential extraction in water, chelating agent (CDTA) and a pectin lyase treatment, was compared for each CWM. Variability of the yields and compositions of the CWM were small and few differences were statistically significant. There were differences in the partitioning pattern of the pectin during fractionation but also a high standard deviation of the yields between repetitions.
Article
Simple sugars, oligosaccharides, polysaccharides, and their derivatives, including the methyl ethers with free or potentially free reducing groups, give an orange-yellow color when treated with phenol and concentrated sulfuric acid. The reaction is sensitive and the color is stable. By use of this phenol-sulfuric acid reaction, a method has been developed to determine submicro amounts of sugars and related substances. In conjunction with paper partition chromatography the method is useful for the determination of the composition of polysaccharides and their methyl derivatives.
Article
The reaction of β-elimination which splits specifically the glycosidic linkages next to methoxylated galacturonic acid units without steric limitation may be used for the determination of the sequence of methyl esters along pectin molecules. However, due to competitive de-esterification, completeness of the reaction has never been achieved. In order to improve the extent of degradation, the influence of temperature, pH and buffer concentration on the β-elimination reaction in aqueous solutions has been investigated. Examination of kinetics revealed that any increase of temperature increases the rate of the β-elimination reaction more than that of the de-esterification. On the other hand, any decrease of pH decreases the rate of β-elimination but, much less than the rate of de-esterification. Buffer concentration plays an important role by controlling the pH through its buffering capacity as well as the availability of hydroxyl ions. Increasing the temperature up to 115°C and decreasing the pH down to 5·0 improved the splitting of the glycosidic bonds of a high methoxyl peetin backbone from 5·5 to 38% (53% of the glycosidic bonds contiguous to a methoxylated galacturonide unit). In spite of the appearance of various secondary reaction products, the absorbance at 235 nm can be used to estimate the extent of degradation.
Article
Cell walls were prepared from apple parenchyma by a phenol:buffer procedure. Polyphenols were extracted from freeze-dried apple parenchyma by methanol and water:acetone, and purified by preparative HPLC. Interactions were quantified by bringing into contact suspended cell walls and polyphenol solutions. Hydroxycinnamic acids and (-)-epicatechin did not bind to cell walls. Binding of procyanidins was fast and reached up to 0.6 g per g cell walls. The amounts of procyanidins bound increased with the initial concentration and with DPn. Procyanidins could be partially desorbed by buffer, more being desorbed in the presence of dissolved cell wall polysaccharides. They were totally desorbed using 8 M urea or acetone:water. Higher polymers were bound selectively from procyanidin mixtures, and very high average DPn were obtained in extensively washed complexes. Binding of procyanidins inhibited enzymic degradation of the cell walls.
Article
Pectin breaks down rapidly by heating with buffer at pH 6.8. This degradation is dependent on the presence of the ester. The rapid decrease in viscosity and increase in reducing end groups are indicative of a splitting of glycosidic bonds within the pectin chain macromolccules. The breakdown products show an absorption maximum at 235 mμ, react with thiobarbituric acid to give a product which absorbs at 547 mμ, and on treatment with ozone give rise to the formation of oxalic acid. These observations strongly indicate the formation of an unsaturated compound by way of a trans elimination reaction which results in the removal of the H atom at C-5 and of the glycoaidic residue at C-4.
Article
The adsorption of procyanidins on cell wall material were quantified by bringing into contact a solution of procyanidins and a suspension of cell wall material. The influence of structural features such as degree of polymerisation (DP) and percentage of galloylation (% gall), and of physico-chemical parameters such as pH, ionic strength, temperature and presence of ethanol were investigated. The amount of procyanidins bound to the cell wall increased with the DP, the % gall, and the proportion of (+)-catechin, the last indicating an effect of the stereochemistry of the flavan-3-ols. Complex formation between procyanidins and cell wall material was not affected by pH in the range 2.2-7 but it was decreased by urea, dioxane and ethanol. Adsorption increased with increasing ionic strength and decreased with increasing temperature. This indicated that the bonds which governed the interaction between procyanidins and cell wall material were weak energy bonds of the type hydrogen bond and hydrophobic interaction.
Article
The adsorption of condensed tannins (procyanidins) on solid cell wall material was quantified using the Langmuir isotherms formulation. Six tannins fractions differing by their size (number average degree of polymerisation between 2.5 and 65) and composition (presence of galloyl groups from to 0 to 22%, proportions of (+)-catechin to (-)-epicatechin from traces to one CAT for three EPI) were used. Two cell walls differing only by their physical characteristics were obtained by mild or harsh drying, with surface areas of 2.15 and 0.52 m(2)/g, respectively. The total amounts of procyanidins retained on the cell wall materials increased with their concentrations while the proportions of retained decreased, and a plateau was reached at high concentrations. The apparent affinity of procyanidins for CWM isolated from apples increased with their molecular weight. Decrease of the CWM porosity by harsh drying slightly decreased the apparent affinity and increased the apparent saturation levels when constants were expressed relative to cell wall weight, but strongly increased both apparent affinity and apparent saturation levels per surface units.
Dietary fiber analysis and applications
  • S Cho
  • J W Devries
  • L Prosky
Cho, S., Devries, J. W., & Prosky, L. (1997). Dietary fiber analysis and applications. Gaithersburg: AOAC International.
Automatisation du dosage des substances pectiques par la méthode au méta-hydroxydiphényl
  • Thibault
Thibault, J.-F. (1979). Automatisation du dosage des substances pectiques par la méthode au méta-hydroxydiphényl. Lebensmittel-Wissenschaft und -Technologie, 12, 247-251.
Dietary fibre content of thirteen apple cultivars