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Physico-chemical and rheological properties of Bengal gram (Cicer arietinum L.) starch as affected by high temperature short time extrusion
Abstract
Starch isolated from Desi Bengal gram seeds after conditioning to moisture contents of 16% and 18% was given a high temperature short time extrusion treatment (HTST). Physicochemical, morphological and rheological properties of untreated and treated starches were studied. Proximate composition of native starch revealed 9.2 g/100 g moisture, 0.01 g/100 g fat, 0.22 g/100 g ash and 0.25 g/100 g protein. Extrusion treatment led to a significant reduction (p ≤ 0.05) in amylose content of treatments from 32.5 to 30.4 g/100 g. Also there was reduction in Hunter colour ‘L’ value (91.6–78.5) with increase in ‘a’ (0.0–0.4) and ‘b’ (10.8–14.8) colour values of samples upon extrusion. Swelling index, solubility index and light transmittance presented a significant (p ≤ 0.05) increase upon extrusion. Pasting properties of extruded treatments decreased significantly(p ≤ 0.05) upon extrusion with increase in the moisture content from 16 to 18%. Scanning electron micrographs of native Bengal gram starch revealed small, spherical and smooth surfaced granules while granules were not visible after extrusion due to loss of granular structure. The storage modulus (G′) of both untreated as well as treated starches increased with the increase in angular frequency, thereby depicting the dominance of elastic behaviour over viscous behaviour. The FTIR spectra of extruded samples revealed reduction in intensities of hydroxyl, alkyl and carbonyl stretches after extrusion.
... Extrusion can effectively modify food materials to yield intermediate ingredients (precooked flours, texturized proteins) or ready-to-eat finished products like expanded snacks and other extruded breakfast cereals (Yovchev et al. 2017). This technology has the advantages of being an economical and sustainable continuous process since it uses short processing times and requires low water and energy inputs with no waste generation (Wani et al. 2019). The effects on chemical composition and physical characteristics due to high temperature, high shear forces, and variable moisture during extrusion have been studied mainly in cereals and soybean (Fallahi et al. 2016;Martínez et al. 2014;Sharma and Gujral 2013). ...
... Water holding capacity (WHC) was determined according to the methodology of Guzmán-Ortiz et al. (2015) whereas the water solubility index (WSI) was calculated with the method of Wani et al. (2019). Foaming capacity was determined according to Martínez et al. (2014) with slight modifications: a suspension of 30 mL with a protein content of 1% was whipped with an Ultra Turrax (IKA T18 basic, Wilmington, NC) at 14,000 rpm for 1 min and the foam volume was recorded after 30 s to calculate foaming capacity. ...
... There were no significant differences in WSI among the samples. An increase in WSI has been related to the amount of soluble molecules in the flour (Wani et al. 2019). Moreover, it is known that high temperature and SME input during extrusion could cause starch damage by means of dextrinization and disruption of the starch granules (Guzmán-Ortiz et al. 2015;Xu et al. 2014). ...
In this study, the effects of extrusion cooking of whole chickpea flour in preparation for its further hydrolyses with proteases and amylases were evaluated. The thermoplastic extrusion process was carried out varying processing moisture (15.6% or 22.55%), final barrel temperature (143°C or 150 °C), and screw speed (450 rpm, 580 rpm, or 700 rpm) to generate three specific mechanical energy (SME) inputs (127.95 Wh/kg, 161.58 Wh/kg, and 199.13 Wh/kg). After extrusion, flours were hydrolyzed with alcalase and α-amylase in order to maximize soluble compounds after hydration. In general, extrusion did not affect chemical composition but caused structural modifications that influenced functional properties and in vitro protein and starch digestibilities. Extruded chickpea flours presented higher content of soluble proteins and increased starch hydrolysis after alcalase and α-amylase treatment, respectively. It was found that extrusion treatment of chickpea with a SME input of 127.95 Wh/kg produced at 22.5% processing moisture, 150 °C of final temperature, and 580 rpm of screw speed in combination with the later alcalase/α-amylase treatments achieved the highest degree of starch hydrolysis (84%) and the release of both soluble proteins (70%) and total soluble solids (62%). These results suggest that amylolytic and proteolytic digestion combined with the extrusion process could transform the whole chickpea flour into a valuable soluble food ingredient with adequate contents of proteins and starch-derived dextrins and sugars.
... Modified starch with higher water absorption capacity and good gel properties could play a unique role in the processing of cereal products (Gao, Cheng, Fu, Wu, & Tang, 2022). Extrusion processing is a well-known physical method for starch modification, which is characterized by environmental-friendly, highefficiency and energy-saving (Qiao et al., 2012;Wani, Farooq, Qadir, & Wani, 2019). Different from the conventional extrusion cooking technology, low temperature extrusion could effectively improve the nutrient retention rate and modify the pasting and rheological properties of the extrudates (Liu et al., 2017b). ...
In this study, low temperature extrusion-modified potato starch (MPS) was added to improve properties of whole wheat dough and textural quality of resulted youtiao. Extrusion temperature (60, 90 ℃) and barrel moisture content (30, 42 and 54%) were set as test variables. The results suggested that the low temperature extrusion processing caused moderate gelatinization and improved gel-forming properties of potato starch. MPS addition decreased the setback by up to 46%, and enhanced the viscoelasticity of whole wheat dough significantly. Compared to the whole wheat-based youtiao, the addition of 10% MPS decreased the hardness by up to 72%, and increased the springiness and specific volume by 32% and 22%, respectively. The addition of MPS prepared at lower extrusion temperature (60 ℃) and moderate moisture content (42%) resulted in the optimum textural qualities of whole wheat youtiao. This study will help better understand the role of MPS in whole wheat-based food product.
... This is possibly the result of mineral participation in several interactions with nutrients during the process. Wani et al. (2019) also reported a decrease of 18.18% in the ash content in extruded starch. Lipids was significantly reduced (p < .05) ...
Background and objectives
Most of the snacks in the market contain a single cereal and show nutritional deficiencies.The aim of the study was to optimize the conditions of the extrusion process for a snack with barley/corn mix and their physicochemical evaluation, amino acid content, protein digestibility and resistant starch as a healthy snack.
Findings
The regression model indicated that the variables water absorption index, water solubility index and hardness can be explained by the models. Expansion index showed no significant effect. The optimal conditions of the process of extrusion were: feed moisture 38%, die temperature 130 °C and barley/corn mix 50:50. An unflavored snack with 392.11 kcal / 100g was obtained, considering it is flavored, its estimated energy contribution is around of 446.11 kcal/100g. The concentration of essential amino acids in the extrudate meets the requirements established by FAO/WHO/UNU for children and adolescents. Protein digestibility increased and the content of available and resistant starch was reduced.
Conclusions
The optimal conditions of extrusion allowed to obtain an alternative snack with the essential amino acid requirements and higher protein digestibility.
Significance and novelty
The combination of two cereals, allows to supplement the requirement of essential amino acids and greater protein digestibility.
... Compared with native starch, TSE samples had a higher swelling power at 50-60 • C, showing the degree of damage to starch caused by extrusion-induced starch gelatinization could increase the swelling capacity at 50-60 • C. However, TSE samples had a lower swelling power at 70-90 • C, which may be due to higher temperature promoted the crosslinking of starch, thereby keeping fewer sites available for interaction with water causing swelling power to decline (Wani, Farooq, Qadir, & Wani, 2019). On the contrary, TSE-CP samples displayed higher values than TSE ones. ...
The influence of twin-screw extrusion (TSE), cold plasma (CP, 1, 5, and 9 min), and their combination (TSE-CP) treatment on the structural, physicochemical, rheological, solubility, and in vitro digestive properties of potato starches were studied. The results showed that CP slightly changed the starch granules morphology, maintained the growth ring and crystalline structure, promoted depolymerization of the amylopectin branch chain, and increased crystallinity and the ΔH value. It is worth noting that the resistant starch content increased from 84.80 to 86.46% in the short time CP modified potato starch. Meanwhile, TSE and TSE-CP treatments influenced surface morphology, growth ring of potato starch significantly. However, the dually modified potato starch using combined TSE and CP treatments promoted depolymerization of longer chains, increased the proportion of shorter chains and solubility, and improved the degree of hydrolysis. Furthermore, the single and dual treatments did not change the FT-IR spectra pattern. This study suggests that the combination between TSE and CP had more profound modification than the single treatment. The TSE combined with CP is an eco-friendly, thermal, and non-thermal combination technology, which can improve the multi-scale structure of starch and enhance physicochemical properties. Also, the dual treatment can be used to produce modified starch for industrial applications.
Development and utilization of high quality vegetable protein resources has become a hotspot. Food extrusion as a key technology can efficiently utilize vegetable protein. By changing the extrusion conditions, vegetable protein can obtain unique functional properties, which can meet the different needs of food processing. However, extrusion of single vegetable protein also exposes many disadvantages, such as low degree functional properties, poor quality stability and lower tissue fibrosis. Therefore, addition of polysaccharide has become a new development trend to compensate for the shortcomings of extruded vegetable protein. The unique functional properties of vegetable protein-polysaccharide conjugates (Maillard reaction products) can be achieved after extrusion due to regulation of polysaccharides and adjustment of extrusion parameters. However, the physicochemical changes caused by the intermolecular interactions between protein and polysaccharide during extrusion are complex, so control of these changes is still challenging, and further studies are needed. This review summarizes extrusion modification of vegetable proteins or polysaccharides. Next, the effect of different types of polysaccharides on vegetable proteins and its regulation mechanism during extrusion is mainly introduced, including the extrusion of starch polysaccharide-vegetable protein, and non-starch polysaccharide-vegetable protein. Finally, it also outlines the development perspectives of extruded vegetable protein-polysaccharide.
Rice starch has high digestibility due to its large carbohydrate content. Macromolecular enrichment of starch has the tendency to retard rate of starch hydrolysis. Hence, the current investigation was aimed to check the combined effect of extrusion assisted addition of rice protein (0, 10, 15 and 20 %) and fibre (0, 4, 8 and 12 %) to rice starch on physico-chemical and in-vitro digestibility characteristics of starch extrudates. It was observed from the study that 'a' and 'b' values, pasting temperature and resistant starch of starch blends and extrudates increased with the addition of protein and fibre. However, lightness value, swelling index, pasting properties and relative crystallinity of blends and extrudates decreased with the addition of protein and fibre. Maximum increase in thermal transition temperatures was observed for ESP3F3 extrudates due to absorption capacity of protein molecules which led to late onset of gelatinization. Therefore, enrichment of protein and fibre to rice starch during extrusion can be considered as a novel approach to reduce rate of rice starch digestion for catering nutritional requirements of diabetic population.
To better understand the correlation between structure and properties in thermoplastic starch biopolymer blend films, the effects of amylose content, chain length distribution of amylopectin and molecular orientation of thermoplastic sweet potato starch (TSPS) and thermoplastic pea starch (TPES) on microstructure and functional properties of thermoplastic starch biopolymer blend films were studied. After thermoplastic extrusion, the amylose contents of TSPS and TPES decreased by 16.10 % and 13.13 %, respectively. The proportion of the chains with the degree of polymerization between 9 and 24 of amylopectin in TSPS and TPES increased from 67.61 % to 69.50 %, and from 69.51 % to 71.06 %, respectively. As a result, the degree of crystallinity and molecular orientation of TSPS and TPES films increased as compared to sweet potato starch and pea starch films. The thermoplastic starch biopolymer blend films possessed a more homogeneous and compacter network. The tensile strength and water resistance of thermoplastic starch biopolymer blend films increased significantly, whereas thickness and elongation at break of thermoplastic starch biopolymer blend films decreased significantly.
To illustrate the correlations between molecular structures and the film-forming properties of thermoplastic starch from various botanical sources, starches from cereal, tuber and legume were modified by thermoplastic extrusion and the corresponding thermoplastic starch films were prepared including thermoplastic corn starch (TCS), thermoplastic rice starch (TRS), thermoplastic sweet potato starch (TSPS), thermoplastic cassava starch (TCAS) and thermoplastic pea starch (TPES) films. TPES film displayed a higher tensile strength (6.28 MPa) and stronger water resistance, such as lower water solubility (15.70 %), water absorption (42.35 %), and water vapor permeability (0.285 g·mm·h-1·m-2·kPa-1) due to higher contents of amylose and B1 chains. TCAS showed a smoother and more amorphous film due to higher amylopectin content, resulting higher elongation at break and larger opacity. TCS film was the most transparent due to a compacter network and more ordered crystallinity structure, which was suit for the packaging of fresh vegetables and aquatic products, whereas TCAS film was the opaquest, which protected package foods from light such as meat products, etc. The outcome would provide an innovative theory to regulate accurately the functional properties of thermoplastic starch films for different food needs.
Fortified rice kernels (FRK) are extruded rice‐shaped kernels manufactured by blending broken rice flour and vitamin–mineral premix. In this study, four parboiled and three raw rice with intermediate amylose content (20–24%) were processed to manufacture FRK. The system parameters (torque and die pressure), physicochemical properties (length, lightness, water absorption index and water solubility index), cooking properties (cooking time, solid loss, elongation) and textural properties of FRK were analysed and correlated using the Pearson correlation coefficient. The torque and die pressure were 16.76–22.76 Nm and 92.56–136.41 bar, respectively. Compared to raw rice, the parboiled rice showed the highest torque, die pressure and axial expansion in uncooked FRK while longer cooking times, higher elongation ratio and hardness; lesser water absorption ratio and solid loss in cooked FRK. The raw rice FRK showed higher lightness. There was a significant difference between all FRK for water absorption index (1.74–2.52) and water solubility index (2.06–3.53%). Fortified rice kernels from raw and parboiled rice.
Herein, corn starch samples with different moisture contents (native corn starch, 30, 35, 40, 45, and 50%) were prepared by twin-screw extrusion, and the structural and physical properties were analyzed and correlated. Scanning electron microscopy observed the morphology, attenuated total reflection-Fourier transform infrared spectroscopy investigated the double helix structure, X-ray diffraction analyzed the crystal region, ion chromatography observed the chain length distribution, and rapid viscosity analyzer measured the viscosity of corn starch samples. We found that the corn starch crystallinity, degree of order, and double helix degree decreased with increasing moisture content. The moisture content has a crucial role in the peak viscosity, breakdown, final viscosity, and setback in pasting property experiments. With the increase in moisture content, the longer chain was transformed into a shorter chain, and the dispersion of molecular weight distribution continuously increased. This study provides a theoretical basis for the production of extruded corn starch.
This study characterized and compared 13 gluten-free (GF) flours (rice, brown rice, maize, oat, millet, teff, amaranth, buckwheat, quinoa, chickpea, gram, tiger nut, and plantain) for their nutritional and functional properties. For all GF flours investigated, starch was the major component, except for gram, chickpea, and tiger nut flours with lower starch content (<45%), but higher fiber content (8.8–35.4%). The higher amount of calcium, magnesium, zinc, potassium, phosphorus, similar values for iron and lower content of sodium in gram, makes this flour a good alternative to chickpea or other GF flour to develop healthier food products. Amaranth flour had a high protein digestibility, while tiger nut and millet flours were less digestible. Gram, chickpea, quinoa, buckwheat, and oat flours fulfilled amino acids recommendation for daily adult intake showing no limiting amino acid. Total polyphenolic content and antioxidant capacity showed higher values for buckwheat, followed by quinoa and maize flours. Gram, chickpea, maize, and quinoa flours are good candidates to improve health conditions due to lower saturated fatty acid content. The findings of this study provide useful insights into GF flours and may contribute to the development of novel gluten-free products like bread, cookies, or pasta.
This paper presents study of the rheological characteristics of the melt of the fish and vegetable mixture biopolymer in the pre-die zone of a single-screw extruder. The analysis of the flow index, being less than one, and that of the flow curves of the fish and vegetable mixture biopolymer melt, intended for production of expanded potato snacks, showed that the melt in a certain range of deformation rates can be attributed to pseudoplastic fluids. The results of the study represent important data in the design of the extruders molding units, on which the stability of the finished products quality depends. The results of the study can be used for mathematical modelling of the flow of the biopolymer melt in the pre-die zone of the extruder and can serve as justification of the screw rotational speed range in order to obtain extrusion foodstuffs of stably high quality.
Extrusion-cooking is advantageous for vulnerable foods and offers a chance to use raw materials which have not previously displayed great economic importance or have even been regarded as waste. Rice and pulse milling by-products due to the low price and easy conversion to processed products result in increasing demand for conversion of these by-products into useful products. It delivers good profit for the processors and in turn providing the consumer a healthy pulse based product to choose from, which is now lacking in the market. This study focuses on optimizing the process variables and to study the extrudate characteristics from blends of bengal gram and rice using single screw extruder. Central composite rotatable design was used to design the experiment with the die head temperature (150-190°C), screw speed (80-100 rpm) and bengal gram level (5-25%) as independent variables. The effect of the variables on the product responses (bulk density, water absorption index, water solubility index, expansion ratio, colour) was carried out. The changes in die head temperature and bengal gram composition were found to have significant effect to the product responses while compared to change in screw speed which is found to have a lesser significant effect to the product response.
Functionalities and relationships between raw and extruded maize flour blends were studied. The extruded flour had higher water absorption and water solubility indices, and had no differential scanning calorimetry endotherm. The parameters of RVA peak, breakdown, setback, and final viscosity were lowered and the parameters of cold viscosity were improved as the fraction of the extruded flour in the mixture increased. In starches from raw flour, a bimodal distribution of the chain length was found by gel permeation chromatography while in the extruded starches only one fraction was observed. The dough quality of 60% raw and 40% extruded flour mixture was found to be better than with other mixture proportions.
Extrusion is a modern procedure for processing different types of raw materials and production of wide range of food products, where the corn grits are often used as main raw materials. Therefore the aim of this study was to determine the effect of screw configuration (4:1 and 1:1), moisture content (15% and 20%) and particle size of corn grits on properties of extrudates. Samples were extruded in the laboratory single screw extruder Brabender 19/20 DN, at temperature profile 135/170/170 °C, using die with 4 mm diameter. Physical and rheological properties, digestibility and starch damage of the obtained extrudates were determined, and results were compared with control samples of non-extruded corn grits. Lower moisture content and usage of screw with compression ratio 4:1 increased expansion ratio and fragility, but decreased bulk density and hardness of extrudates, regardless of granularity. After extrusion process water absorption index increased, but peak, hot and cold viscosity of all samples decreased, with more pronounced effect in grits extruded with lower moisture content and with screw 4:1. Extrusion caused a reduction of the resistant starch content and increase starch damage of all samples.
Starches separated from four kidney bean cultivars were modified by acetylation to reduce retrogradation and increase gel stability and compared with respective native starches (data of native starch reported by Wani et al., 2010). Acetylation was carried out by treating starches with 0.04 and 0.08 g of acetic anhydride per gram of starch dry weight basis (dwb) at 25 °C and pH between 8.0 and 8.5. The extent of acetylation increased proportionally with the concentration of acetic anhydride used. The pasting curves of 10.7% starch determined by Rapid Visco Analyzer at 160 rpm showed that acetylation decreased the setback viscosity values by 0.64–34.58% and pasting temperature by 4.4–9.2 °C when compared with the native starch. Differential scanning calorimetry observations also revealed significant (P ≤ 0.05) decrease in gelatinisation temperature of acetylated starches than the corresponding native starches. Hardness of starch gels varied between 14.3 and 44.0 g, which was significantly (P ≤ 0.05) lower than the corresponding native starch gels.
Rice flour is an interesting alternative for developing gluten free products, but its features do not always meet
the process requirements. The objective of this study was to modify the functional properties of rice flour by combining extrusion and size fractionation. Different extrusion conditions (barrel temperature, feed moisture content and feed rate) were applied to vary the severity of the treatment on the flour constituents. Extrusion and mechanical fractionation of the rice flours modified their behavior affecting hydration, thermal and pasting features, besides their susceptibility to enzymatic hydrolysis. Specifically, onset and peak temperature increased and gelatinization enthalpy decreased when increasing barrel temperature of the extrusion. Fine flours with stronger extrusion (high temperature barrel) showed the highest susceptibility to enzymatic hydrolysis. Overall, the combination of both physical treatments maybe an attractive alternative for obtaining clean label rice flours with modified features.
The aim of the present study was to determine the chemical composition and estimation of nutritive value of kabuli and desi type chickpeas using in vitro gas production technique in sheep. The samples were collected from East Azerbaijan, Iran, pea packaging and processing factories. The feed samples (200 mg from each) were incubated with rumen liquor taken from three fistulated rams at 2, 4, 6, 8, 12, 24, 48, 72 and 96 h. The results showed that neutral detergent fiber (NDF) and crude fiber (CF) in desi type were significantly higher than that of kabuli (p < 0.01) while crude protein (CP), non fibrous carbohydrates (NFC) and soluble sugars in kabuli were significantly greater than that of desi (p < 0.05). Total tannins in desi type were higher than kabuli chickpeas (p < 0.05). There were no significant differences between dry matter (DM), organic matter (OM), ether extract (EE), starch and total phenolic compounds (TPC) content of the two experimental chickpea types. There were significant differences in organic matter digestibility (OMD), short chain fatty acids (SCFA) and metabolizable energy (ME) contents of the two chickpea types (p < 0.05). Gas productions at 24 h for kabuli and desi types were 78.66 and 73.96 ml, respectively. Overall, it seems that the nutritive value of kabuli type was higher than that of desi for ruminants.
The purpose of this study was to extract locust bean gum (LBG) from whole seeds by two different dehulling pre-treatments. The first process consisted in separating the endosperm (gum) from the hull and the germ after seeds’ pre-treatment with boiling water. The second one used acidic pre-treatment. Then the composition and the physicochemical characteristics of the isolated gum were studied in order to evaluate the effect of extraction process. Comparisons to commercial samples and temperature influence on solubility and rheological properties are included.The yield and quality of Locust bean gum from whole seeds depended on the separation method used. The separation of the seed components by boiling water pre-treatment furnished a higher yield of yellowish endosperm (51–61% w/w), whereas acid dehulling pre-treatment gave an off-white gum yield (37–48% w/w). However, the mannose and galactose content, the solubility, the molecular size and the dynamic viscosity, were higher for LBG from acid dehulling pre-treatment. In addition, a considerable influence of solubilization temperature on macromolecular characteristics and on viscosity properties was noticed.
Density (ρ), viscosity (η) and ultrasonic velocity (u) of binary mixtures of methyl orange and water were measured at different concentrations and at different temperatures; several useful parameters such as excess volume, excess velocity, and excess adiabatic compressibility have been calculated. These parameters are used to explain the nature of intermolecular interactions taking place in the binary mixture. The above study is helpful in understanding the dye/solvent interaction at different concentration and temperatures.
Pregelatinized starch was made from indica rice starch using a so-called “improved extrusion cooking technology” (IECT) under 30%–70% moisture content. IECT-pregelatinized starch (IPS) had higher water solubility and water absorbability compared to native starch at low temperature. For pasting properties, the breakdown and setback viscosities of IPS were significantly (p < 0.05) lower than native starch, suggesting improved gel stability and reduced short-term retrogradation. The rice starch granules lost their integrity in IPS, and formed a honeycomb-like structure with increased moisture content in the raw material. These properties can be explained in terms of molecular structural features, particularly the large reduction in the size of molecules, but without significant changes in the chain-length distributions of amylopectin component, and no significant change in amylose fraction. These results indicate that IECT is suitable for preparing IPS with desirable water solubility and gel stability properties.
The effect of feed moisture content (10, 14 and 18%) and die temperature (110 and 160 °C) on functional properties, specific mechanical energy (SME), morphology, thermal properties, X-ray diffraction pattern (XRD), Fourier transform infrared spectroscopy (FTIR) and amylose-lipid complex formation of extruded sorghum flour was investigated. Results showed that the extrusion cooking significantly changed the functional properties of extruded sorghum flour. Increasing feed moisture increased the peak gelatinization temperature (Tp), the degree of gelatinization (%) and starch crystallinity (%) while it decreased the gelatinization temperature ranges (Tc - T0), starch gelatinization enthalpy (ΔHG) and amylose- lipid complex (%) formation. With increasing die temperature, the degree of gelatinization and amylose-lipid complex formation increased and the starch Tp, Tc-T0, ΔHG and crystallinity decreased. The FTIR spectra also showed that the extrusion cooking did not create new functional groups or eliminate them in sorghum protein, whereas the sorghum extrudate protein had random coil conformation.
Starch isolated from lentil was subjected to two treatments namely sonication and, a dual treatment of sonication and irradiation at a dose of 5 kGy. Lentil yielded 26.12 ±1.56 g starch/100 g of lentil. Chemical composition of native starch revealed 7.83 ± 0.28% moisture, 0.23 ± 0.30% protein, 0.35 ± 0.05% fat and 0.10 ± 0.00% ash. The results revealed that pasting properties of lentil starch were not affected upon sonication. However, these decreased significantly (p ≤ 0.05) upon dual treatments. Amylose content of starch was 31.16 ± 1.80 g/100 g which showed a decrease upon sonication and dual treatments. Sonication and dual treatments (sonication and irradiation) decreased hunter ‘L’ value while ‘a’ and ‘b’ values showed an increase. Syneresis decreased more or less insignificantly upon sonication. However, a significant decrease in syneresis was observed after 120 h storage following dual treatments. Sonication did not decrease the functional properties significantly while as dual treatment induced a significant decrease in functional properties. FT-IR analysis revealed a decrease in the intensities of O-H, C-H and OC stretches and CH2 bending upon sonication and dual treatments.
The study was conducted to evaluate the effect of gamma irradiation (0, 0.5, 1, 2.5, 5 and 10 kGy) on physicochemical, functional and thermal properties of chickpea starch. Results revealed that the pasting properties showed a significant (p≤0.05) decrease in peak viscosity, final viscosity, setback viscosity, trough viscosity and pasting temperature in dose dependent manner. Swelling, solubility index, oil absorption capacity and water absorption capacity increased significantly with dose, while as syneresis decreased with dose. Gelatinization temperatures To, Tp and Tc decreased significantly with dose. X-ray diffraction showed a characteristic C type pattern of the starches and the crystallinity decreased with dose. Scanning electron microscopy revealed small oval shaped starch granules and slight surface fissures were seen in the irradiated starch treated with 5 and 10 kGy.
Starch-guar gum mixtures were obtained by extrusion using a three-variable Box-Behnken statistic design. Morphology, expansion index, viscosity, crystallinity and digestion in vitro of the extruded samples were analyzed through response surface methodology (RSM). The extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the samples. Starch-guar gum samples showed expansion index and viscosity up to 1.55 and 1400 mPa s, respectively. The crystallinity of the samples was modified by adding guar gum to the extrudates, showing correlation between long-range order (X-ray diffraction) and short-range order (FTIR spectroscopy). Guar induced microstructural changes and its role in gelatinization-melting processes was significant. The rate of glucose release decreased from 0.47 to 0.43 mM/min when the extrusion temperature decreased. However, adding guar gum to starch had no significant effect on glucose release. Overall, the extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the extruded samples.
Effect of extrusion on the functional, rheological, thermal and morphological properties of the modified cereal flours from different cereals was assessed. Rice flour, wheat flour and flour, in combination (rice: wheat, 50:50) were passed through twin screw extruder to obtain modified cereal flours at variable conditions (barrel temperature: 175 and 190°C, feed moisture: 14 and 16% and screw speed: 500 rpm). Functional properties [water absorption index (WAI), water solubility index (WSI), swelling index and viscosity] improved in modified cereal flours as compared to the unmodified flours. Modified flours showed lower paste viscosity as compared to unmodified flours, which was a desirable property for modified flours to be utilized as a functionality ingredient in food products. Processed flours recorded higher onset (To), peak (Tp) and endset (Te) temperature and showed higher enthalpy change (∆H) than the raw cereal flours. Degree of gelatinization was higher in flours processed at higher barrel temperature and feed moisture. The morphological pattern of modified flours was determined by SEM. The starch surface of cereal flours (modified and unmodified) differed from each other with respect to their morphological pattern.
Starches separated from three black gram cultivars were modified by acetylation and compared to their native starches. Acetylation was carried out by treating starches with 0.04 and 0.08 g of acetic anhydride/g of starch dry weight basis (db) at 25 °C. The extent of acetylation increased proportionally with the concentration of acetic anhydride used. Retrogradation of acetylated starch pastes decreased significantly (p ≤ 0.05) as revealed by significant decrease in syneresis, increased freeze thaw stability and increased light transmittance. The pasting curves of 10.7 % starch slurries showed that acetylation decreased the setback viscosity values by 51.2-82.8 % and pasting temperature by 3.1-5.6 °C than respective native starches. Differential scanning calorimetry observations also revealed significant decrease in gelatinisation temperature of acetylated starches than native starches. Hardness and adhesiveness of starch gels varied between 10.3 and 32.6 g and 4.6-82.3gs, respectively which were significantly lower than corresponding native starch gels.
Native and extruded corn, field pea (FP), and kidney bean (KB) starches were evaluated for structure, in vitro digestibility and functional properties. Starches were extruded at 20 and 24% feed moisture (FM) using a twin screw extruder. Starches extruded at higher FM showed higher L* (luminosity) values while lower a* and b* values. Extrusion led to complete structure destruction, reduced crystallinity and formation of V type polymorph in starches. Extruded starches showed lower water absorption index (WAI), retrogradation (syneresis) and paste viscosities but higher water solubility index (WSI) as compared to native starches. CS showed lower retrogradation tendency than KB and FP starches. WAI, WSI, and retrogradation were higher at lower FM than those at higher FM. Extruded starches showed higher rapidly digestible starch (RDS) and lower resistant starch (RS) content. All starches extruded at higher FM showed significantly lower RDS content as compared to those extruded at lower FM. KB showed the highest RS content followed by FP and CS. Starches extruded at higher FM showed higher RS content as compared to those extruded at lower FM.
Starch isolated from Indian Horse Chestnut (Aesculus indica Colebr.) was subject to irradiation at 0, 5, 10, 15 kGy doses. Effect of irradiation on physicochemical properties of native starch was studied. The result revealed increase in water absorption capacity from 0.94 to 1.00 g/g, carboxyl content from 0.00 to 0.06%, solubility from 0.15 to 0.53 g/g and freeze thaw stability. Syneresis, pasting properties and pH were reduced following irradiation treatment. Syneresis decreased from 3.47 to 0.64% after 120 h refrigerated storage. Peak viscosity reduced from 5156.5 to 1422.5 cP, setback viscosity from 1191.5 to 73.0 cP and final viscosity from 3232.0 to 410.5 cP. X-ray diffraction pattern showed A type of pattern in native as well as irradiated starches. Granule morphology of native and irradiated starches under scanning electron microscope revealed that granules were round, oval, irregular or elliptical with smooth surfaces. Pearson correlation studies revealed that irradiation dose was positively correlated with water absorption capacity, oil absorption capacity, and solubility index and negatively correlated with syneresis, swelling index, freeze thaw and pasting properties.
Native rice starch (NRS, amylose/28.9%) was gelatinized by improved extrusion cooking technology (IECT) and retrograded (RRS) after low temperature storage (4 °C). The retrogradation behaviour of RRS was changed to low retrogradation percentage and low retrogradation rate. The retrogradation resulted in a high compact morphology. The melt enthalpy change and percentage of retrogradation of RRS was 3.68 J/g and 37.7%, respectively, compared to those of NRS (9.75 J/g, 100%). The retrogradation percentage for RRS was low during storage as shown as a low retrogradation rate (0.21 d−1) and a high Avrami exponent (0.89). The pattern of rice starch changed from A-type to amorphous and B-type. Both the relative crystallinity of RRS (12.7%) by the X-ray diffractograms and the ratio of the band height (0.63) in the FTIR spectra were low. The analysis of retrogradation structure and short-range molecular order further confirmed the retrogradation behaviour of rice starch after IECT treatment.
Macromolecular structure of manioc starch, extruded without and with lipids (oleic acid, dimodan, soya lecithin and copra) was studied, using chemical, enzymic, viscometric and chromatographic methods. Twin screw extrusion-cooking led to a macromolecular degradation of both amylose and amylopectin. The formation of lower molecular weight material was observed by a decrease of intrinsic viscosities of both components and also by their behaviour on Sepharose CL-2B, whereas no modification of β-amylolysis and iodine-binding capacity could be detected. The macromolecular degradation was increased by higher temperature and screw speed of the extruder, and was decreased by adding lipids during extrusion. Lipids such as fatty acids, mono- and triglycerides have been shown to act as lubricants (each type in its distinctive way). Lipid extraction, by different solvents, appears to have a low efficiency. Although the addition of triglycerides during extrusion reduces the macromolecular degradation, leading to a high solubility, the amylose-lipid complexes reduce the water-soluble fraction. This fraction was shown to be mainly composed of aggregated amylopectin-like material and to be highly stable after successive freeze-thaw cycles.
Effect of barrel temperature (80°–100°C) and amylose content (28.6 gkg, 22.3 gkg and 5.0 gkg) of rice upon extrusion cooking on macromolecular profile of starch was studied by gel permeation chromatography (GPC) of the rice flour on Sepharose CL-2B. Starch in all rice samples was separated into two main fractions, viz. Fraction-I, a high molecular weight, was excluded by gel, amylopectin, and Fraction-II, a low molecular weight, that entered the gel, amylose. Extrusion cooking of rice led to the degradation of high molecular weight fraction of the starch, the extent of degradation increasing with increasing severity of extrusion conditions. The absorption maxima (λmax) of iodine complex of the fraction-I showed an increase after extrusion cooking and this increase was more in the non-waxy variety of rice than in waxy.
The physicochemical and functional properties of Canavalia ensiformis starch hydrolyzed with HCl were studied. The factors analyzed were HCl concentration (0.5−1.5%), temperature (45−55°C), and reaction time (3−6 h). Alkali number and viscosity were the response variables. A 23 factorial design with five replicates of the central trial was used. Hydrolyzed starch with 1.5% HCl at 55 °C for 6 h reached an alkali number of 11.92. The hydrolysis reaction did not present important changes on the starch chemical composition except for an ash content reduction. A comparison between these hydrolyzed starches and the native starches showed a viscosity (36.4 cP), swelling power (21.86 g of water/g of starch), and retrogradation reduction. A 45.3% solubility increment was found. Gelatinization temperature did not vary (76−82 °C). Keywords: Canavalia; starch; acid hydrolysis; functional properties
The characterisation of starches from kabuli and desi type chickpea seeds was investigated by monitoring amylose content, swelling power, solubility, synaeresis, water-binding capacity and turbidity properties. Total amylose and apparent amylsoe content were 31.80% and 29.93% for kabuli and 35.24% and 31.11% for desi, respectively. The shape of starch granules varied from round to oval or elliptic. The transition temperatures (To, Tp and Tc) were (62.237, 67.000 and 72.007 °C) and (59.396, 68.833 and 77.833 °C) for kabuli and desi starches, respectively. The ΔH value of kabuli type was higher than that of desi type. The crystal type of chickpea starches was a typical CA-type pattern. Breakdown and setback viscosity of kabuli starch were lower than those of desi starch, indicating high heat and shear stability. Kabuli starch showed a higher value of Mw (5.382 × 107 g/mol) than desi starch (3.536 × 107 g/mol). Both kabuli and desi starches belonged to low glycaemic starches from measuring starch fractions and hydrolysis index.
Extrusion cooking, as a multi-step, multi-functional and thermal/mechanical process, has permitted a large number of food applications. Effects of extrusion cooking on nutritional quality are ambiguous. Beneficial effects include destruction of antinutritional factors, gelatinisation of starch, increased soluble dietary fibre and reduction of lipid oxidation. On the other hand, Maillard reactions between protein and sugars reduce the nutritional value of the protein, depending on the raw material types, their composition and process conditions. Heat-labile vitamins may be lost to varying extents. Changes in proteins and amino acid profile, carbohydrates, dietary fibre, vitamins, mineral content and some non-nutrient healthful components of food may be either beneficial or deleterious. The present paper reviews the mechanisms underlying these changes, as well as the influence of process variables and feed characteristics. Mild extrusion conditions (high moisture content, low residence time, low temperature) improve the nutritional quality, while high extrusion temperatures (200 °C), low moisture contents (<15%) and/or improper formulation (e.g. presence of high-reactive sugars) can impair nutritional quality adversely. To obtain a nutritionally balanced extruded product, careful control of process parameters is essential.
Raman and infrared spectra of starch samples from sweet potato and different varieties of cassava (tapioca) are reported.
Three regions of the spectra, the OH stretching region (3560-3000cm-1), the CH stretching region (3000-2800cm-1) and the finger print region (1600-200cm-1), have been studied. The results are discussed in relation to the hydrogen bonding and the properties of starch samples.
A range of substituted starches has been prepared at moderate temperature (≤90°C) from gelatinised potato starch by treatment in lithium chloride/N,N-dimethylacetamide (DMAC) solution with acyl chlorides. Oleoyl, palmitoyl, lauroyl, capryloyl and butyryl modified starches have been synthesised with degrees of substitution (DS-values) ranging from 0.3 to 3. Characterisation by FT-IR spectroscopy and elemental analysis has confirmed reaction and degree of substitution obtained. DS-Values were controlled by metered addition of stoichiometric quantities of the required acyl chloride. Such structural modification of starch resulted in a significant change of physicochemical properties, and increased hydrophobicity with increasing acylation extent. It was found that the modified starches had improved thermal stabilities and enhanced solubilities in organic solvents.
Blends of rice and chick pea (Cicer arietinum) flours, containing 20% moisture, were extruded through a single-screw extruder. The extrusion process variables were: (i) feed ratio (ratio of the solids of rice and chick pea flour=100:0, 90:10 and 80:20), and (ii) temperature of die (100, 125 and 150°C). The torque during extrusion was measured, so also were product characteristics, such as expansion ratio, bulk density and shear strength. Response surfaces for these parameters were generated using a second degree polynomial. Incorporation of chick pea into rice flour decreased torque and product expansion, but increased bulk density and shear strength. The temperature of the die had a linear effect on these parameters. Optimum extrusion conditions — resulting in minimum torque and bulk density — were estimated.Sensory assessment of the extruded samples fried in oil indicated that extrusion of rice or rice-chick pea blends could be an alternative method of producing acceptable snacks.
The effects of microwave cooking and other traditional cooking methods such as boiling and autoclaving on the nutritional composition and anti-nutritional factors of chickpeas (Cicer arietinum L.) were studied. Cooking treatments caused significant (P<0.05) decreases in fat, total ash, carbohydrate fractions (reducing sugars, sucrose, raffinose and stachyose, while verbascose was completely eliminated after cooking treatments), antinutritional factors (trypsin inhibitor, haemagglutinin activity, tannins, saponins and phytic acid), minerals and B-vitamins. Cooking treatments decreased the concentrations of lysine, tryptophan, total aromatic and sulfur-containing amino acids. However, cooked chickpeas were still higher in lysine, isoleucine and total aromatic amino acid contents than the FAO/WHO reference. The losses in B-vitamins and minerals in chickpeas cooked by microwaving were smaller than those cooked by boiling and autoclaving. In-vitro protein digestibility, protein efficiency ratio and essential amino acid index were improved by all cooking treatments. The chemical score and limiting amino acid of chickpeas subjected to the various cooking treatments varied considerably, depending on the type of treatment. Based on these results, microwave cooking is recommended for chickpea preparation, not only for improving nutritional quality (by reducing the level of antinutritional and flatulence factors as well as increasing in-vitro protein digestibility and retention rates of both B-vitamins and minerals), but also for reducing cooking time.
Native green arrow pea (GAP), eston lentil (EL), othello pinto bean (PB), black bean (BB) and express field pea (FP) starches were heat-treated at 100 °C for 16 h at a moisture content of 30%. The heat treatment did not change granule size and shape. The surfaces of GAP and EL were modified after heat treatment. Heat treatment decreased amylose leaching (GAP > FP~EL > BB~PB) and the swelling factor (EL ~ FP > GAP > BB ~ PB). The X-ray diffraction intensities increased in GAP starch, but decreased in the other starches (FP > BB > PB > EL). However, the X-ray pattern of all starches remained unchanged after heat treatment. Differential scanning calorimetry of the heat-treated samples showed a broadening of the gelatinization temperature range and a shifting of the endothermal transition towards a higher temperature (EL-EP>BB-PB). However, the gelatinization enthalpy (ΔH) of all starches remained unchanged. The susceptibility towards hydrolysis by porcine pancreatic α-amylase increased on heat treatment (BB > EL > FP > PB > GAP). The action of α-amylase on the starches decreased ΔH in EL and FP. However, ΔH decreased only marginally in PB and BB. Acid hydrolysis (2.2 N HCl) increased on heat treatment (BB>FP~EL~PB>GAP). The results showed that bonding forces within the amorphous regions of the granule, crystallite orientation and the granule surface (in GAP and EL) are altered during heat treatment, the magnitude of these changes being dependent upon the starch source.
The physical properties and enzymatic digestibility of acetylated starches prepared in the laboratory from high amylose (Hi-Maize™ 66% amylose; and GELOSE 50, 47% amylose), waxy (MAZACA 3401X, 3.3% amylose), and normal (22.4% amylose) maize starches provided by Starch Australasia Limited were studied. Acetylation decreased temperature at peak viscosity, while slightly increasing peak viscosity compared to the matching unmodified starch. It increased cool paste viscosity except in the case of normal starch. All the acetylated starches had lower onset temperature (To), intermediate temperature (Tp), completion temperature (Tc) and endothermic energy (ΔH) than their unmodified starches, but acetylation increased swelling power and solubility. After acetylation, the hardness of all the starch gels decreased; adhesiveness decreased and springiness increased except for waxy starch where it was the reverse; cohesiveness increased in each case. Acetylation increased the clarity of all the starches, except for waxy which showed a decrease. Acetylation increased the enzymatic digestibility compared to the unmodified starches.
The barley flour–grape pomace blends were extruded in a 30 mm APV co-rotating twin-screw extruder. Response surface methodology using a central composite design was used to evaluate the effects of independent variables, namely die temperature (140–160 °C), screw speed (150–200 rpm) and pomace level (2–10%, db) on product responses (expansion, bulk density, texture and color). Sensory analysis was carried out for selected extrudates for appearance (color, porosity), taste (bran flavor, bitterness and sweetness), off-odor, texture (hardness, crispness and brittleness) and overall acceptability. Multiple regression equations were obtained to describe the effects of each variable on product responses. The product responses were most affected by changes in temperature, pomace level and to a lesser extent by screw speed. Blends of 2% grape pomace extruded at 160 °C, 200 rpm and 10% grape pomace extruded at 160 °C, 150 rpm had higher preference levels for parameters of appearance, taste, texture and overall acceptability. However, graphical optimization studies resulted in 155–160 °C, 4.47–6.57% pomace level and 150–187 rpm screw speed as optimum variables to produce acceptable extrudates. The results suggest that grape pomace can be extruded with barley flour into an acceptable snack food.
Physico-chemical properties of starches from kidney beans
- Wani
Physicochemical and nutritional characteristics of extruded flours from fresh and hardened chickpeas (Cicer arietinum L)
- Milan-Carrillo
Improving starch for food and industrial applications
- Jobling
Evaluation of rice flour modification by extrusion cooking
- Hageniamana
Rheological properties of potato starch paste with the addition of kaolin
- Drozdz