Article

Quality characteristics and oxidative stability of coconut oil during storage

Authors:
  • Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara
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Abstract

The main objective of this study is to investigate some quality characteristics based on which we can evaluate oxidative stability of coconut oil during 12 month of storage. The progress of lipid oxidation was assessed by measuring peroxide value (PV), p-anisidine value (AV) and total oxidation value (TOTOX). The low peroxide value (0.24–0.49 meq/kg oil) signifies a high oxidative stability, while p-anisidine values were in the range 0.19-0.87. Fourier transform infrared (FTIR) spectroscopy was used to monitor the peak changes as effect of oxidation during storage. The prominent peak change observed during storage of coconut oil was at frequency 1742 cm-1 which corresponded to the ester carbonyl functional group of the triglycerides resulted from the hydroperoxide decompositions. These results suggest that coconut oil during 12 month on storage keeps its good chemical properties.

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... The same behavior was verified by Strieder et al., (2017), who found the value of 2.7 meq·kg -1 for rice oil bleached at 110 °C. According to Moigradean et al., (2012), the amount of perox- ide in vegetable oil indicates its oxidative level and, thus, its tendency to become rancid. ...
... In the oxidation reaction, the primary oxidation products are decomposed into minor substances such as aldehydes, which lead to a rancid smell and taste in the oil. These compounds are determined by the anisidine value (Moigradean et al., 2012;Marina et al., 2009). In Tables 1 and 2, an increase in the anisidine value can be seen for the BNO, indicating the formation of secondary oxidation products dur- ing the bleaching step. ...
... 80 and 95 °C, indicating that aldehyde was absorbed at these temperatures. The TOTOX value indicates total oxidation in the oil, which includes primary and sec ondary compounds formed in the oxidative reactions (Moigradean et al., 2012). It can be observed in Table 2 that the lowest values for the BDO and BNO were obtained at the temperature of 95 °C, indicating that this temperature favored adsorption and promoted less oxidation than the other temperatures. ...
Article
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Refining conditions are very important to obtain high-quality rice oil. This work aimed at evaluating the effect of bleaching temperature in chemical and physical refining processes to avoid losses in γ-oryzanol and carotenoids. In addition, the aspects related to rancidity were investigated. Samples of degummed oil (obtained by a physical procedure) and of neutralized oil (obtained by a chemical procedure) were provided by a local industry. The oils were bleached at 80, 95 and 110 °C using 1% (w w-1) activated earth. The temperature of 95 °C was the best in relation to oxidative stability. The γ-oryzanol and carotenoids were better preserved through physical refining than by the chemical procedure by about 64 and 84%, respectively. However, the oxidation indicators were high for the oil bleached by the physical procedure, indicating that bleaching without prior neutralization is viable, but it is necessary to obtain an industrial crude oil with less oxidation.
... El aceite de coco es un producto con un gran valor agregado, y entre sus diversas aplicaciones, destaca el uso en las industrias de jabones y alimentos (Correia et al., 2014). Tiene una larga vida útil y se utiliza en las industrias de panadería, alimentos procesados, farmacéutica, cosmética y aceites capilares (Moigradean;Poiana;Gogoasa, 2012). Este aceite se ha destacado en el mercado como un posible complemento en el tratamiento de la obesidad (Duarte et al., 2019). ...
... El aceite de coco es un producto con un gran valor agregado, y entre sus diversas aplicaciones, destaca el uso en las industrias de jabones y alimentos (Correia et al., 2014). Tiene una larga vida útil y se utiliza en las industrias de panadería, alimentos procesados, farmacéutica, cosmética y aceites capilares (Moigradean;Poiana;Gogoasa, 2012). Este aceite se ha destacado en el mercado como un posible complemento en el tratamiento de la obesidad (Duarte et al., 2019). ...
... El aceite de coco es un producto con un gran valor agregado, y entre sus diversas aplicaciones, destaca el uso en las industrias de jabones y alimentos (Correia et al., 2014). Tiene una larga vida útil y se utiliza en las industrias de panadería, alimentos procesados, farmacéutica, cosmética y aceites capilares (Moigradean;Poiana;Gogoasa, 2012). Este aceite se ha destacado en el mercado como un posible complemento en el tratamiento de la obesidad (Duarte et al., 2019). ...
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El aceite de la fruta seca de coco (Cocos nucifera L.) tiene un origen vegetal extraído del árbol de coco, perteneciente a la familia Arecaceae y la subfamilia Cocoideae. Tiene un gran potencial para uso industrial ya que tiene aplicaciones en varias áreas productivas. La búsqueda constante de productos que puedan agregar valor y traer beneficios a la humanidad ha llevado al crecimiento en el uso de aceite de coco en procesos industriales, ya que es un aceite considerado estable debido a su alto nivel de saturación en comparación con otros aceites comestibles. El objetivo de esta investigación fue evaluar las características oleoquímicas del aceite de coco a partir de procesos de extracción en frío y aceites industrializados, verificando el análisis de los parámetros indicativos de la calidad de estos aceites, que fueron los siguientes: índices de acidez, peróxido, yodo y porcentajes de ácidos grasos libres. Se realizó un análisis comparativo de aceite de coco comercial y aceite de coco adaptado por el método Bligh & Dyer. Las muestras en ambos tratamientos se obtuvieron de tiendas locales y se analizaron por triplicado. Los parámetros analizados fueron similares para ambos aceites tratados, se encontraron dentro de los estándares requeridos por la legislación RDC No. 270 y CODEX alimentarius e indicando buena calidad para el consumo. Solo los datos para el índice de yodo en los dos tratamientos fueron altos, y pueden haber sido influenciados por la estacionalidad de la fruta, por el método de extracción o por procesos industriales.
... Autooxidation is a self-sustaining free radical mechanism that produces primary products such as hydroperoxides (Márquez-Ruiz et al., 2007;Phatanayindee et al., 2012). Hydroperoxides primarily accumulate as main oxidation products, subsequently breaking down to form secondary oxidation products such as alcohols, aldehydes, ketones and free fatty acids, eventually resulting in the development of rancidity (Kanner, 2007;Moigradean et al., 2012;Pannico, 2014). Furthermore, hydroperoxides can react with amino acids residues in the Maillard reaction, causing excessive browning (Walton, 2005). ...
... Furthermore, Fig. 2 shows that roasting significantly (p < 0.001) preserved the quality of kernels throughout the storage period as indicated by PV lower than 10 meq O 2 kg −1 for both cultivars. 'Beaumont' had the lowest PV of 5.139 meq O 2 kg -1 on day 70, indicating that kernels were fresh throughout the storage period (Moigradean et al., 2012). This could be attributed to the fact that roasting further reduces moisture content needed for microbial growth, enzyme activity and chemical reactions such as hydrolysis of lipids into free fatty acids, often leading to the development of rancidity therefore, extending the storability of kernels (Borompichaichartkul et al., 2013;Das et al., 2014;Pannico et al., 2015). ...
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Macadamia nut is rich in monounsaturated fatty acids, which are known to reduce the risk of cardiovascular diseases when included as part of a healthy human diet. On the negative side, high concentrations of unsaturated fatty acids lead to oxidative reactions, which result in rancidity thus decreases the quality of the nut. Drying and roasting are, therefore, needed to reduce moisture content and hence alleviate the above-mentioned problems. This research was conducted to evaluate and compare the quality properties of raw and roasted macadamia nuts during the accelerated storage of 70 days. Two commercially important macadamia cultivars, namely, 'A4' and 'Beaumont' were used as model cultivars. Nuts were roasted at 125 °C for 15 min using a hot air oven dryer. Roasted kernels of 'A4' and 'Beaumont' cultivars had significantly lower concentration of peroxide value (PV), high concentration of flavonoids, phenols and antioxidants activity and good sensory quality compared to raw kernels which had a higher concentration of polyphenol oxidase activity, PV, low concentration of flavonoids, phenols and antioxidant activity and poor sensory quality during the accelerated storage of 70 days. These results indicated that roasting significantly improved kernel quality and shelf life of 'A4' and 'Beaumont' macadamia cultivars.
... Several studies on the stability of coconut oil have demonstrated that, in general, co_oil deterioration could be caused by oxidation and microorganisms [44][45][46][47][48][49]. Coconut oil stored in a dark bottle at room temperature (25 • C) possesses better oxidative properties than other vegetable oils, such as sunflower and sesame oil, as it contains saturated fatty acids [44,45]. ...
... Coconut oil stored in a dark bottle at room temperature (25 • C) possesses better oxidative properties than other vegetable oils, such as sunflower and sesame oil, as it contains saturated fatty acids [44,45]. Experiments have demonstrated that coconut oil quality is not affected during 12 months of storage [46]. The relatively small moisture content (<1%), low iodine value (13.18 ± 0.22), and low BOD (biochemical oxygen demands, 500 mg/L) of the co_oil show that it has relatively great biostability and extremely resistant to the development of rancidity due to small content of unsaturated fatty acid [47,48]. ...
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The role of thermal mass in indoor air-cooling during the day is a common area of study, which is particularly relevant for an era characterized by energy crises. Thermal energy storage (TES) technologies for application in rooms and buildings are not well developed. This study focuses on the use of coconut oil (co_oil) as a temperature control agent for room air conditioning systems in tropical countries such as Indonesia, given its capability to store large amounts of heat at temperatures around its melting point. Heat exchange studies between co_oil and the air environment were performed by considering three factors: Temperature difference between co_oil and the air environment, the heat absorption behavior and the release of co_oil, and the mass of co_oil required to have a significant effect. The co_oil cell sizes were formulated as responses to natural day and night air temperature profiles, while the performance of the co_oil mass for decreasing room air temperature was predicted using a thermal chamber.
... Ya¤lar›n bir di¤er önemli kalite kriteri, iflleme ve depolama esnas›nda oksidasyona karfl› direncini ifade eden oksidatif stabilitedir (35). Oksidatif stabilite kat› ve s›v› ya¤lar›n kalitesinin de¤erlendirilmesinde önemli bir parametredir (36). Belirtildi¤i gibi sabunlaflmayan madde miktar›, iyot say›s›, ya¤ asidi bileflimi, tokoferol içeri¤i gibi de¤erler oksidasyon stabilitesi hakk›nda bilgi verse de, bu amaca yönelik olarak genellikle peroksit de¤eri, -anisidin analizi, toplam oksidasyon analizi (Totox-Totoks), UV ›fl›¤›nda özgül so¤urma analizi, f›r›n testi (Schaal Oven), aktif oksijen metodu (AOM, Ransimat metodu) gibi analizler ve bunlardan elde edilen de¤erler kullan›lmaktad›r (16,19,20,37,38). ...
... Di¤er bir ifade ile triaçilgliserollerdeki (TAG) yüksek molekül a¤›rl›kl› doymufl veya doymam›fl karbonil bilefliklerinin seviyesini ölçmektedir. Anisidin de¤eri, ço¤u kez peroksit de¤eri ile birlefltirilerek toplam oksidasyon de¤eri ya da totoks de¤eri (2PV + -AV) olarak da kullan›lmaktad›r (36 (14). Elde edilen bu bulgular ayn› familyadan kabak çekirde¤i ya¤› ile karfl›laflt›r›ld›¤›nda, de¤erler aras›nda önemli bir farkl›l›k olmad›¤› anlafl›lmaktad›r (38). ...
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Watermelon is a member of the Cucurbitaceae family and an annual plant which is cultivated in a wide range of tropical and semi-tropical regions of the world. Turkey is the third watermelon producer in the world. It is consumed primarily as a fresh fruit but also used in producing juices, syrups, jellies, jams, and canned food. In addition, its skin is used in animal feeding and the seeds are used in the cosmetics and pharmaceutical industries. However, in recent studies, nutritional aspects of watermelon seeds have been investigated, and it was proposed to be consumed in the food industry. The first functionality of watermelon seeds is that they have a high fat content and are nutritious. Physical, chemical and nutritional properties of watermelon seed oil have been the subject of several studies to determine the usability of it in the food industry, and its purity and quality criteria were also investigated. The oil of watermelon can be extracted from the seeds in various ways; such as cold pressing or solvent extraction. It is light yellow in color and is potentially an important source of essential fatty acids.
... Oxidation of some fatty acids, especially unsaturated fatty acids, may lead to high peroxide numbers (Natalia et al, 2019). Low oxidation is defined as a peroxide value between 1 and 5 meq/kg, moderate oxidation is defined as a value between 5 and 10 meq/kg, and high oxidation is defined as a value greater than 10 meq/kg (Moigradean et al, 2012). However, SLSI standard limits the peroxide value of coconut oils in general to a maximum of 3 meq/kg (Moigradean et al, 2012). ...
... Low oxidation is defined as a peroxide value between 1 and 5 meq/kg, moderate oxidation is defined as a value between 5 and 10 meq/kg, and high oxidation is defined as a value greater than 10 meq/kg (Moigradean et al, 2012). However, SLSI standard limits the peroxide value of coconut oils in general to a maximum of 3 meq/kg (Moigradean et al, 2012). The peroxide values of coconut oil, as well as the number of unsaturated fatty acids, were taken into account in this present study. ...
Conference Paper
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Coconut oil, commonly used edible oil in Sri Lanka, has number of health benefits such as cholesterol-lowering effects, reduced risk of cardiovascular diseases, weight loss, improved cognitive functions, and antimicrobial activity. Demand for coconut oil rapidly increases. Coconut oil is produced on small to large scale. In Ampara district, there are numerous small-scale traditional coconut oil producers that produce oils that lack of proper knowledge and scientific practices. This study is designed to compare selected quality parameters of coconut oil produced locally with SLS standards (SLS 32:2017). Oil samples were collected from Addalaichenai, Akkaraipattu and Pottuvil. The free fatty acid (FFA), moisture, and peroxide value (PV) were determined using standard methods. The results obtained were the mean values for free fatty acid, moisture, and peroxide value ranged from 1.069±0.15 to 1.1402±0.38 mg NaOH/g oil, 0.3486±0.00 to 1.7920±1.49 % and 1.0913±0.47 to 1.8836±0.55 meq /kg respectively. All three samples had higher moisture and free fatty acid content than the standard value (0.4 and 0.8) respectively, and lower peroxide value (>3). A significant difference was observed in peroxide value, which was lower than the SLS value, whereas the moisture content and free fatty acid value were not found to be significantly differ across all areas. The local manufacturers must improve their oil processing scientifically and hygienically, so as to improve the quality on par with the SLS standards and to provide quality oil to the consumers. However, modern scientific manufacturing methods should be introduced by the local manufacturer.
... All the three samples with the antioxidant packs had significant increase of p-AV between 7th and 8 th week of storage indicating reaction of panisidine with produced aldehydes. Hydroperoxides are unstable at storage therefore, they decompose to give secondary oxidation products that are p-anisidine-reactive (Moigradean et al., 2012). ...
... All the three samples with the antioxidant packs had significant increase of p-AV between 6 and 7 th week of storage indicating reaction of p-anisidine with produced aldehydes. Hydroperoxides are unstable at storage therefore, they decompose to give secondary oxidation products that are p-anisidine-reactive (Moigradean et al., 2012) No significant difference (P<0.05) was observed between oil in AT and EAE/AT. Comparing EAE with its bend with AT (EAE/AT) shows that AT reduced the effectiveness of EAE which could be as a result of their incompatibility. ...
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A natural antioxidative Monodora myristica (Ehuru) active film package for lipid food preservation was produced by cast method. 0-5% w/w ehuru antioxidant extract (EAE) was incorporated into PSF film. Into another PSF resin was incorporated 5% alpha tocopherol (AT) and another, a blend of (EAE)/ α-tocopherol (AT). Tetrahydrofuran (THF) and N-methylpyrrolidinone (NMP), were used as solution solvent, in ratio 3:1. The radical scavenging abilities of the developed films were analyzed and compared to the pure PSF (control) using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) solution. Finally, the ability of the films to stabilize peanut oil against oxidation were tested by measuring some rancidity analysis of the actively packaged peanut oil. The result showed that the radical scavenging properties of the active films increase with concentration of EAE infused inside the film increased from (0%-5%), and 5% EAE incorporation created a compact film without any optical noticeable pore. This was confirmed by the permeation rate of oxygen across the film which decreased from (0.1079-0.0277) m 3 /s as concentration EAE increased. Generally, results showed that natural antioxidant derived from Ehuru seeds (EAE) exhibited the best delay of lipid hydrolyses by exhibiting the shortest oxidation time. It was also deduced that concentration between 2.5 and 5% could comfortably be used to produce the active package because their effect on oxidation of lipid oil are not significantly different from each other 7.85± 1.13 and 7.27± 1.69 respectively. Results obtained from the oxidative analysis confirmed the effectiveness of the active film of natural antioxidant derived from Ehuru seeds (EAE) in slowing down lipid hydrolysis and increasing the oxidative stability of peanut oil, having the smallest PV of 7.35±2.00 and the smallest P-AnV of 18.12± 1.57
... Increasing iodine value is an indication of an increased in the degree of unsaturation of fat in the cookies. A similar result was reported by Moigradean et al. (2012). The peroxide value gives an indicator of the detoriation of fat in the products (Adeleke and Abiodun, 2010). ...
... The peroxide value was observed to increase significantly (p>0.05) with an increase in the percentage of avocado pear pulp. Moigradean et al. (2012) classified a product with a peroxide value above 10 meq/kg as a high oxidation state and below as a low oxidation state. Thus, all the cookies produced in this study can stay long because the values are low and found to be within values for low oxidation state products. ...
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The partial substitution of margarine with mature avocado pear pulp in the production of cookies was investigated. Five cookie samples were produced with avocado pear pulp and margarine blends in the ratios 80:20%, 70:30%, 60:40%, 50:50%, and 100% margarine serve as the control, labeled as B, C, D and E and A, respectively while the other ingredients used remain constant. The physico-chemical (proximate compositions, free fatty acids (FFA), iodine value, and peroxide value) and sensory qualities of the cookies were evaluated using standard methods. The results show ranged in moisture (11.13 to 14.60%), crude protein (6.93 to 7.83%), crude fat (16.00 to 18.03%), ash (1.40 to 2.09%), crude fiber (0.29 to 0.62%), carbohydrate (59.70 to 62.79%), FFA (0.35 to 1.01 mg KOH/g), iodine value (75.63 to 81.17 g I2/100 g) and peroxide value (2.96 to 5.27 meq/kg). The partial substitution of margarine with avocado pear pulp produced nutritious cookies with desirable organoleptic qualities. Also, the results demonstrated that cookies had acceptability up to a 30% level of substitution with avocado pear pulp. The findings indicated the feasibility of avocado pear pulp in fat-reduced cookies preparation, this will reduce the pressure in using only margarine in cookies making and diversify the use of avocado pear.
... These are what give the oil a rancid smell, and they are measured by the p-anisidine value (p-AV) (Przybylski and Eskin, 1995). The overall oxidation state of the oil can be estimated by calculating the TOTOX; that is, both the primary and secondary oxidation products, (Moigradean et al., 2012). In polyunsaturated fatty acids, thiobarbituric acid (TBA) value can be used to indicate secondary oxidation (Moigradean et al., 2012). ...
... The overall oxidation state of the oil can be estimated by calculating the TOTOX; that is, both the primary and secondary oxidation products, (Moigradean et al., 2012). In polyunsaturated fatty acids, thiobarbituric acid (TBA) value can be used to indicate secondary oxidation (Moigradean et al., 2012). During storage of fresh cooking oil, the extent of degradation can be measured using the peroxide value; it gives a measure of the extent to which an oil sample has undergone primary oxidation. ...
... [3][4] Coconut oil relatively slow to oxidize and resistant to rancidification. 5 However, during processing, such as frying and other heating, it may increase the oxidation and rancidification of fatty oil. Formation of several primary and secondary oxidation products such as lipid hydroperoxides, aldehydes, ketones, hydrocarbons, and alcohol found and may be harmful to human health. ...
... In the study, the control sample underwent an increase in the PV during storage at week 0 to week. 5 The PV of the DMMMP sample has increased at the 2 nd week of storage, while the sample with PMAV and TBHQ can withstand the PV until the 5 th week ( Figure 6). It indicated that PMAV and TBHQ could delay peroxide formation in the storage. ...
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The antioxidants effect of two aminomethyl derivatives of 2-methoxyphenol: 4,6-di[(morpholin-4-yl)methyl]-2-methoxyphenol (DMMMP) and 5-[(pyrrolidin-1-yl)methyl]vanillic acid (PMVA) on enhancing thermal and oxidative storage stability of coconut oil was performed using tert-butylhydroxyquinone (TBHQ) as a comparative standard. The efficacy on thermal stability test was carried out by heating at 180 oC for 1, 3, and 6 hours, while the efficacy on the storage stability test was performed using an accelerated method by heating at 60oC for 5 weeks. The concentrations for MDMMP was 200, 350, and 500 ppm; for PMVA was 200, 275, and 350 ppm; and for TBHQ was 200 ppm. Free fatty acid (FFA) level, peroxide value (PV), and p-anisidine value (p-AV) were used as parameters to assess the level of oxidative stability of coconut oil. The results showed that the addition of DMMMP 200, 350, and 500 ppm, and PMVA 200 and 275 ppm did not inhibit FFA, peroxide, and aldehyde formation. In thermal stability study, PMVA (350 ppm) could inhibit the free fatty acid release, and formation of secondary oxidation products compounds on thermal stability comparable to TBHQ (200 ppm) addition, but only TBHQ that could inhibit peroxide formation for 6 h. In storage stability, DMMMP (all concentration) could not delay the fatty acid release, while PMVA (all concentration) and TBHQ (200 ppm) delayed that for 2 and 5 weeks, respectively. DMMMP (all concentration) delayed peroxide formation for 2 weeks, while PMVA (all concentration) and TBHQ (200 ppm) delayed peroxide formation for 5 weeks. All compounds only delay the formation of secondary oxidation products for 1 week. In conclusion, the efficacy of PMVA as an antioxidant against thermal and storage oxidative stability of coconut oil is higher than DMMMP but lower than TBHQ.
... Edible coconut oil is another possibility, due to its high content of saturated fat, up to 92% [14,15,[23][24][25][26]. Coconut oil products labeled as virgin coconut oil and refined coconut oil are commonly found in the marketplace, where the difference is in the oil extraction method from the flesh of the coconut fruit [24,25]. Both have relatively good shelf life: 2 years for refined coconut oil and 5 years or more for virgin coconut oil (virgin coconut oil contains more anti-oxidants than refined coconut oil and some manufacturers state that it has an indefinite shelf life), which can even be much longer if coconut oil is stored in well-sealed opaque containers to reduce photodegradation and oxidation [27,28]. ...
... Note that the CNO PCM is only feasible and cost effective if it remains stable for several years, but the shelf life could be extended by adding stabilizing agents and/or by use in sealed metal tubes. Encapsulation in sealed metal tubes would help with heat transfer and also prevent photodegradation and oxidation of the PCM, and keep parasites away from the CNO [27,28]. ...
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Edible oils could provide more accessible alternatives to other phase change materials (PCMs) for consumers who wish to build a thermal energy storage (TES) system with sustainable materials. Edible oils have good shelf life, can be acquired easily from local stores and can be less expensive than other PCMs. In this work, we explore whether margarine, vegetable shortening, and coconut oil are feasible PCMs, by investigations of their thermal properties and thermal stability. We found that margarine and vegetable shortening are not useful for TES due to their low latent heat of fusion, ΔfusH, and poor thermal stability. In contrast, coconut oil remained thermally stable after 200 melt-freeze cycles, and has a large ΔfusH of 105 ± 11 J g−1, a low degree of supercooling and a transition temperature, Tmpt = 24.5 ± 1.5 °C, that makes it very useful for TES in buildings. We also determined coconut oil’s heat capacity and thermal conductivity as functions of temperature and used the measured properties to evaluate the feasibility of coconut oil for thermal buffering and passive heating of a residential-scale greenhouse.
... Hydroperoxides, are the main products of lipid oxidation and can ultimately break down in a sequence of composite reactions, to generate secondary products such as alcohols and carbonyl compounds (aldehydes and ketones). These secondary products can then be oxidized to carboxylic acids (Moigradean et al., 2012). The secondary metabolites are usually volatile substances and can result in the formation of rancidity in nuts (Jensen et al., 2001;Pannico, 2014). ...
... Peroxide value is associated with the development of peroxides in unsaturated fat, initiated from the break of double bonds, which produces short chain volatile products responsible for the rancid odour (Canneddu et al., 2016). Peroxide value is the most common parameter often used for characterizing the quality of nuts (Moigradean et al., 2012;Borompichaichartkul et al., 2013). The number of peroxides available in edible oils indicates its oxidative level and therefore, its susceptibility to rancidity. ...
Article
Moisture content (MC), oil content (OC), fatty acid composition and rancidity are considered as major determinants of quality of nuts. These parameters are destructively quantified from a batch of representative samples used to estimate quality of nuts of an entire orchard. Although destructive techniques are helpful, they involve extensive sample preparation and solvent extractions, are slow, expensive and obtained results specifically reflect the properties of the evaluated produce. Recently, non-invasive analytical methods and instruments for evaluating quality of various produce have become popular with researchers putting more effort in developing them. Non-destructive methods are an alternative to traditional methods for inspection of internal quality parameters because they are fast, simple and cost-effective. In this review, invasive and non-invasive analytical methods and instruments for evaluating MC, OC, fatty acid composition and rancidity in different nuts are discussed. This paper also reviews the implementation of visible to near infrared spectroscopy, nuclear magnetic resonance and X-ray computed tomography on nuts for evaluation of quality attributes. Technical challenges and future possibilities for commercial use of these non-invasive methods for quality evaluation of nuts are presented.
... Based on PV, oxidation state is evaluated in three classifications: low (1-5 meq peroxides/kg), moderate (5-10 meq peroxides/kg), and high (above 10 meq peroxides/kg) (Moigradean et al., 2012). The low oxidation is observed in UTSO until 15 mins sonication, where further sonication time further induced oxidation to moderation oxidation. ...
... According to Moigradean et al. (2012), p-AV measures carbonyl composition in fats or oils. The generation of Schiff base which absorbs at 350 nm is due to the reactiveness of carbonyl bonds in aldehyde towards p-AV amine group. ...
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This study aims to investigate the effect of sonication time (2-120 mins) on lipid oxidation and accelerated storage of ultrasound treated sunflower oil (UTSO) and ultrasound treated palm oil (UTPO). Peroxide values (PV) of UTSO and UTPO were measured to assess the oxidative stability of sunflower oil and palm oil. Accelerated storage of UTSO and UTPO were conducted for 24 days at 60 o C with a 6-days-intervals analysis The PV increased gradually with the increasing sonication time and reached the highest PV of 10.25 and 5.67 meq peroxides/ kg in UTSO and UTPO, respectively. The UTPO exhibited higher PV (44.67 meq peroxides/ kg) than UTSO (19.91 meq peroxides/kg) upon accelerated storage. No significant (p > 0.05) difference was observed on the quality of UTSO and UTPO with their controls after 24 days of accelerated storage. Results of this study demonstrated that ultrasound (US) treatment via ultrasonic bath accelerates lipid oxidation process without significant impact on the generation of lipid oxidation by-products during prolonged storage.
... The oxidative level of vegetable oils and their tendency to become rancid is reflected by the amount of peroxides they contain. Thus, oils with high peroxide values are unstable and easily become rancid [28,29]. In the study of Moigradean et al. [28], the POV increased significantly followed by appearance of secondary oxidation products in CO during 12 months of storage. ...
... Thus, oils with high peroxide values are unstable and easily become rancid [28,29]. In the study of Moigradean et al. [28], the POV increased significantly followed by appearance of secondary oxidation products in CO during 12 months of storage. The present study showed that CO stored beyond 24 months had increased levels of MDA and POV when compared with fresh CO indicative of peroxidation and aging. ...
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Background: Exposure to mercury (Hg) and the ingestion of peroxidized edible oil represent a health risk. This study evaluated the effects of peroxidized coconut oil (CO) on the liver and kidney of rats treated with Hg. Methods: Male albino Wistar rats were administered HgCl2 and CO separately or as a combination for 21 days. The concentrations of glutathione (GSH) and malondialdehyde (MDA), as well as the activities of superoxide dismutase (SOD) and catalase (CAT), which were used as markers of oxidative stress were measured in the liver and kidney homogenates. The activities of gamma glutamyl transferase (γ-GT), lactate dehydrogenase (LDH) as well as the levels of bilirubin and creatinine (CREA) as markers of liver and kidney functions were analyzed in the serum. Results: The level of MDA in the kidney and liver homogenates was significantly increased in the HgCl2, CO, and CO+HgCl2 groups when compared to control values (p<0.05). Liver SOD activity and GSH level were increased and CAT activity was decreased, whereas kidney GSH level and SOD activity were decreased and CAT activity was increased in the CO and CO+HgCl2 groups when compared to control values (p<0.05). The increase in CREA and bilirubin levels as well as γ-GT and LDH activities observed in the CO+HgCl2 group when compared to the control values (p<0.05) were associated with pathological changes in both tissues, and were considered to be due to oxidative stress. Conclusions: In summary, peroxidized CO and Hg alone or in combination induces oxidative damage in the liver and kidney of rats.
... [36] An edible oil with a PV > 10 meq kg −1 is categorized as being at a high oxidation state. [37] The PVs of local avocado oils (ranging from 5.22 to 5.44 meq kg −1 ) were found to be lower than those of the oils obtained from the imported Fuerte (6.23 meq kg −1 ) and Shepard (5.85 meq kg −1 ) varieties. In the literature, the PVs of avocado oils have been reported to be in the range of 5.1-12.3 ...
Article
The oils obtained from three Indonesian avocado (Persea americana) cultivars namely Merah bundar, Ijo bundar and Ijo panjang, were compared to the oils obtained from imported Fuerte and Shepard avocado varieties in terms of lipid characteristics and tocopherol content. The oils of all avocado varieties existed in a semisolid form, except that of the Fuerte variety. Free fatty acids and peroxide levels in the oils obtained from locally grown avocado were lower than the levels in the oils obtained from imported avocados, implying that local avocado oils have a better oxidative stability. Interestingly, the tocopherol (alpha, beta, gamma and delta) content of local avocado oils was also much higher than that of imported avocado oils. Meanwhile, differences in the FTIR spectrum of avocado oils were found at frequencies of 1034 and 968 cm−1. There were also some differences in the fatty acid and triacylglycerol composition of avocado oils. Due to these differences, the physicochemical characteristics and the solidification and thermal profiles of the oils obtained from local avocado cultivars were completely different from those of the imported avocado varieties (Fuerte and Shepard).
... [36] An edible oil with a PV > 10 meq kg −1 is categorized as being at a high oxidation state. [37] The PVs of local avocado oils (ranging from 5.22 to 5.44 meq kg −1 ) were found to be lower than those of the oils obtained from the imported Fuerte (6.23 meq kg −1 ) and Shepard (5.85 meq kg −1 ) varieties. In the literature, the PVs of avocado oils have been reported to be in the range of 5.1-12.3 ...
Article
The oils obtained from three Indonesian avocado (Persea americana) cultivars namely Merah bundar, Ijo bundar and Ijo panjang, were compared to the oils obtained from imported Fuerte and Shepard avocado varieties in terms of lipid characteristics and tocopherol content. The oils of all avocado varieties existed in a semisolid form, except that of the Fuerte variety. Free fatty acids and peroxide levels in the oils obtained from locally grown avocado were lower than the levels in the oils obtained from imported avocados, implying that local avocado oils have a better oxidative stability. Interestingly, the tocopherol (alpha, beta, gamma and delta) content of local avocado oils was also much higher than that of imported avocado oils. Meanwhile, differences in the FTIR spectrum of avocado oils were found at frequencies of 1034 and 968 cm−1. There were also some differences in the fatty acid and triacylglycerol composition of avocado oils. Due to these differences, the physicochemical characteristics and the solidification and thermal profiles of the oils obtained from local avocado cultivars were completely different from those of the imported avocado varieties (Fuerte and Shepard).
... The primary products formed are hydroperoxides, which then decompose in a series of complex reactions to produce secondary products such as alcohols and carbonyl compounds, which are mainly responsible for offshore flavors (rancidity) and odors. The peroxide index indicates the amount of primary oxidation products [49]. The results of the peroxide values of formulations B and C are shown in Table 5. Formulation B shows a significantly higher peroxide value than formulation C. ...
Article
Full-text available
Amaranth (Amaranthus cruentus) is a possible alternative to high-nutritional-value crops. Amaranth seeds are considered to be one of the few sources of phytosqualene (up to 8%). The use of squalene and its hydrogenated form squalane in skincare formulations has been steadily increasing, and the demand for these compounds is expected to rise continuously. The aim of this study was to investigate the amaranth oilseed as a potential ingredient for cosmetic applications. First, an experimental design and optimization were carried out in order to obtain amaranth oil rich in squalane instead of squalene through catalytic hydrogenation. Under the optimal conditions, the resulting oil was fully hydrogenated, with higher stability, and more suitable for cosmetic uses. Furthermore, the effect of the addition of amaranth oil and squalane on the rheological and sensory characteristics of moisturizing cream formulations was assessed. As expected, higher contents of oil and polyunsaturated fatty acids were obtained by supercritical CO2 extraction, and were used for the next step of the experiment. Optimization of the experimental conditions resulted in fully hydrogenated amaranth oil, with higher stability and rich in squalane. Better quality of moisturizing cream formulations was achieved when W/O formulations were enriched with 2% oil, or by adding 1% oil and 1% squalane. The formulation rich in squalane showed a better overall quality compared to other formulations.
... (11) A estabilidade oxidativa é um importante parâmetro para avaliar a qualidade de óleos e gorduras, sendo que os compostos antioxidantes presentes nos óleos vegetais são, em parte, os responsáveis por essa propriedade. (12) O óleo de coco possui compostos fenólicos (ácido ferúlico e ácido 4-hidroxibenzoico) que são capazes de prevenir ou inibir a cadeia oxidativa e, consequentemente, a peroxidação lipídica. (13) Nesse sentido, entender as mudanças que os óleos e gorduras sofrem durante o aquecimento é fundamental. ...
Article
Full-text available
O objetivo deste estudo foi avaliar o efeito do tratamento térmico sobre o perfil de ácidos graxos, capacidade antioxidante, oxidação lipídica e características físico-químicas do óleo de coco. As análises foram realizadas com amostras do óleo de coco in natura, aquecido até o ponto de fumaça e utilizado na fritura de batatas. Foi avaliado o perfil de ácidos graxos, os índices de peróxidos e acidez, a formação de malondialdeído e a capacidade antioxidante do óleo de coco nas três condições. O perfil de ácidos graxos não diferiu nas distintas condições de análise; contudo, pode-se observar que o índice de acidez foi significativamente maior no óleo aquecido e utilizado na fritura. Para o índice de peróxidos, esse aumento ocorreu apenas no óleo aquecido. A formação de malondialdeído foi observada em todas as amostras, sendo maior no óleo aquecido, seguido do usado na fritura. A capacidade antioxidante foi menor nas amostras submetidas ao calor (diferença significativa). Conclui-se que os tratamentos térmicos aos quais o óleo de coco foi submetido, foram capazes de alterar suas características físico-químicas e oxidativas. Considerando os possíveis malefícios associados ao consumo de óleos e gorduras degradados, desencorajamos a utilização do óleo de coco submetido a temperaturas elevadas. Enfatizamos a importância da criação de metodologias específicas para avaliação da qualidade de óleos e gorduras submetidas ao aquecimento, por possibilitar um melhor controle dos aspectos nutricionais e sensoriais dos óleos/gorduras destinados ao consumo.
... Fourier transform infrared (FTIR) spectroscopy was used to monitor the peak changes due to oxidation during storage. The results of this study suggest that coconut oil retains its good chemical properties during 12 months of storage (Moigradean et al., 2012). When the quality of coconut oil is evaluated, it is important to consider both nutritional quality and commercial quality. ...
Book
Full-text available
Coconut oil has a multitude of health benefits. Most of the predictions and the interpretations of the nutritional quality of coconut oil are based on the fatty acid composition of coconut oil. This book details the well-established chemistry of the main compounds such as free fatty acids, triglycerides and all other lipid forms as well as the most recently investigated chemistry of the minor compounds such as phenolic fraction of coconut oil. In addition, the recent findings related to the antioxidants present in coconut oils extracted under different conditions, the antioxidant properties as well as health benefits related to both main and minor components of coconut oil are also summarized.
... Oil and fats are important parts of the healthy human diet as they are also used as food preparation and flavoring. Edible oils are vital constituents of our daily diet, which provide energy, essential fatty acids and serve as a carrier of fat soluble vitamins [1][2][3]. Fats and oil belongs to a group of biological substances called lipids. Lipids and triacylglycerol naturally occur in oils and fats. ...
Article
The main objective of this study is to evaluate the antioxidant properties of oregano on refined soybean oil as a result of microwave and induction cook top heating. Oxidation changes were determined by common traditional parameters such as acid value, free fatty acid value, peroxide value as well as by Fourier transform infrared (FTIR) spectroscopy. It has been observed from studies that oregano has powerful antioxidant effect in microwave heated oil samples whereas it does not show any antioxidant properties on induction cooktop heated samples.
... All samples were stored at 60 ± 3ºC for 25 days. Every 4 days, a sample was taken to evaluate its oxidative stability using the following parameters: Peroxide values (AOAC, 2005), ρ-anisidine value (IUPAC, 1979) and totox value (Moigradean et al., 2012). ...
Article
Full-text available
The objective of the present study was to utilize whey and permeate as the by-products of the cheese industry after mixing with kumquat purée and/or paste for producing functional beverages. Physical, chemical, physicochemical, microbiological and sensory properties of kumquat fruit and its purée and paste were studied. The results indicated that kumquat purée and paste are good sources of β-carotene, vitamin C, minerals such as calcium, potassium and magnesium, total phenolic acids and flavonoids. In addition, they have high antioxidant capacity. Physicochemical, microbiological and sensory properties of the prepared functional beverages during cold storage periods were determined. The obtained results indicated that ascorbic acid and β-carotene of all beverages were higher than those of whey and permeate only, with a high level of total phenols, flavonoid content and antioxidant activity. Generally, sensory evaluation of the prepared beverages showed that the addition of purée and paste of kumquat fruit to whey and permeate increased the overall acceptability of these beverages. Total count was in permissible limit while the coliform and moulds & yeasts counts were not detected in all beverages during storage at 4±1°C for 28 days. Beverages containing purée and paste of kumquat fruit could be recommended as new acceptable functional products.
... Deshi ghee and coconut oil are least susceptible to oxidation if stored at room temperature and dark. Diana Moigradean et al. too have mentioned the oxidative stability to be good for coconut oil in their study (16). ...
Article
Full-text available
Introduction and Aim: On storage edible oils not only go rancid but also oxidants are generated which may lead to oxidative damage to the cardiovascular system and lead to carcinogenesis in the long run. With the objective of studying the physico-chemical changes of different edible oils in different storage modes, 11 different samples of edible oil and ghee-sunflower oil, palm oil, soyabean oil, mustard oil, coconut oil, sesame oil, olive oil, rice bran oil, blended oil, deshi ghee and Vanaspati ghee were analysed. Materials and Methods: All the samples were subjected to dark, room temperature and light condition and direct sunlight. Alterations in physical properties and primary and secondary oxidation products were studied and statistically analyzed. Results: All the physical and chemical alterations were highest for direct sunlight exposure (p<0.001). Maximum AV was seen for blended oil 27.86, 29.36, 42.8 for storage under dark, room and sunlight respectively. TBARS was significantly increased in all storage conditions with a maximum for soybean oil under sunlight 32.36μm/gm. On analysis of TOTOX value by Kruskal-Wallis test, there was statistically significant change found for Olive oil (p=0.009), deshi ghee (p=0.026) and Palm oil (p=0.012) under all storage conditions. Conclusion: Soyabean oil should be best avoided because of its maximum oxidation product generation irrespective of any storage conditions. Deshi ghee, coconut oil, and Vanaspati ghee have comparatively better oxidative stability. Deshi ghee should be used after at least 15 days of production.
... From Table-1 the Peroxide value of cocoa butter was estimated to contain higher limit of 1.09, which was found to be significantly differing from the 11 who studied the cocoa butter from various regions and the peroxide value was estimated to be in the range of 0.85 to 4.31meq.O 2 / kg. The materials used for the current study was found to be highly stable in conformity with the findings observed by Moigradean (2012) 12 . that a product with peroxide value between 1 and 5, 5 and 10, and above 10 meq.O 2 / kg were classified respectively as minimally oxidative, moderately oxidative and highly oxidative. ...
Article
Full-text available
A study was carried out to produce chocolates from coconut variants viz, coconut oil, coconut cream and coconut milk as a substitute for cocoa butter. The chocolate prepared with 40% cocoa butter was taken as control. The preliminary trials were conducted with different composition of ingredients for the optimization of the level of substitution of coconut variants. Cocoa butter substituted at the levels of 10 %, 20 % and 30 % by coconut oil, coconut cream and coconut milk respectively were optimized based on the consumer acceptance. The raw materials used in the fabrication of chocolate were subjected to analysed for Peroxide value (PV), Acid Value (AV) and Free Fatty Acid (FFA) content and were found to have desirable oxidative stability.
... RBD oil is made from dried coconut kernel, which is placed in a hydraulic press with added heat, from which the oil is extracted. Because of its high saturated fat content, it is slow to oxidise (Moigradean, Poiana, & Gogoasa, 2012) and is thus resistant to rancidification. Coconut oil contains mainly saturated TAGs (N90%) and is an excellent source of medium chain fatty acids that can be easily burnt for energy. ...
Article
This paper is concerned with the foaming of a range of fats in the absence of added foaming agent/emulsifier. By controlling the temperature on warming from the solid or cooling from the melt, crystals of high melting triglycerides form in a continuous phase of low melting triglycerides. Such crystal dispersions in oil can be aerated to produce whipped oils of high foamability and extremely high stability. The foams do not exhibit drainage and bubbles neither coarsen nor coalesce as they become coated with solid crystals. The majority of the findings relate to coconut oil but the same phenomenon occurs in shea butter, cocoa butter and palm kernel stearin. For each fat, there exists an optimum temperature for foaming at which the solid fat content reaches up to around 30%. We demonstrate that the oil foams are temperature-responsive and foam collapse can be controllably triggered by warming the foam to around the melting point of the crystals. Our hypothesis is given credence in the case of the pure system of tristearin crystals in liquid tricaprylin.
... All samples were stored at 60 ± 3ºC for 25 days. Every 4 days, a sample was taken to evaluate its oxidative stability using the following parameters: Peroxide values (AOAC, 2005), ρ-anisidine value (IUPAC, 1979) and totox value (Moigradean et al., 2012). ...
Article
Full-text available
The present study aimed to evaluate the chemical composition, antioxidant activity, antimicrobial properties and the minimum inhibitory concentrations (MICs) of three essential oils extracted from cumin, rosemary and thyme and their mixture and their effect on physicochemical, microbial, rheological and sensorial attributes of ultrafiltrated (UF)-soft cheese. UF-soft cheese was prepared from UF milk retentate with adding 0.1% of these essential oils. The results revealed that the different essential oils had remarkable antimicrobial effect on the growth of Escherichia coli (E. coli), Salmonella typhimurium (S. typhimurium), Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis), Bacillus cereus (B. cereus), and Aspergillus niger (A. niger). Among essential oils, thyme oil had the highest antioxi-dant activity and antimicrobial effect. Addition of essential oils appeared to affect cheese pH and total volatile fatty acid content during storage period, while total solids and fat contents were slightly affected. Addition of essential oils to retentate resulted in an increment in antioxidant activity and decreased the total bacterial count compared with the control cheese. Sensory evaluation revealed that UF-soft cheese containing essential oils remained acceptable even at the end of storage period. Adding cumin essential oil to UF-soft cheese gained the highest scores for the sensorial attributes. The results concluded that a concentration of 0.1% of essential oils extracted from cumin, rosemary or thyme or their mixture can be used to extend the shelf life of UF-soft cheese for up to 28 days. These essential oils could be successfully used as natural and safe additives in production of UF- soft cheese.
... IV for coconut oil ranges from 7.0-9.5 is highly stable towards atmospheric oxidation. (Diana et al, 2012;Ankrah, 1998). The changes in IV over 5 days of frying oil were 2.19, 2.47, 1.4 and 1.27 g I 2 /100 g oil for all treatment respectively. ...
Article
Serai Kayu or its scientific name is Eugenia polyantha is widely found in the Western part of the South East Asian peninsular and in Western Indonesia. The leaves are commonly taken as "ulam" in Malaysian communities. This paper reports the investigation of the phytochemical constituents and antioxidant potential of aqueous extract from leaves of E.polyantha and the frying quality of coconut oil were evaluated during deep frying of French fries. The amounts of total phenolic and flavonoids content were determined spectrometrically. There were three types of parameter used for frying quality of coconut oil; coconut oil without BHT as a negative control, coconut oil with BHT as a positive control and coconut oil with E.polyantha as a natural antioxidant. The oil quality was assessed by measuring the peroxide value, free fatty acid, iodin value and viscosity. Phytochemical screening of the crude extracts revealed the presence of different kind of chemical groups such as flavonoids, phenol, tannins, saponins, steroids and terpenoids. The result shows the extract had high phenol(213.15 ±1.1 mg GAE/g plant extract) and flavonoid content (2.47 ± 0.1 mg QE/g plant extract) with high DPPH scavenging ability (IC 50 value: 0.15 ± 0.01) compared to BHT (IC 50 value: 0.19 ± 0.01). The result for frying quality of coconut oil indicated that the extract delayed the oil deterioration. The E.polyantha extract significantly (p< 0.05) lowered the rate of oxidation in crude coconut oil, compared to negative and positive control. In general, the present findings suggest that the crude aqueous extract of E.polyantha leaves is a potential source of natural antioxidants and the extract was capable of extending the stability and quality of crude coconut oil and therefore has potential as new source of natural antioxidant for use in deep frying.
... IV for coconut oil ranges from 7.0-9.5 is highly stable towards atmospheric oxidation. (Diana et al, 2012;Ankrah, 1998). The changes in IV over 5 days of frying oil were 2.19, 2.47, 1.4 and 1.27 g I 2 /100 g oil for all treatment respectively. ...
... The high peroxide value of the oil is indicative that the oil is unstable against oxidation. [31,32]. avocado oil should exhibit a high rate of oxidation due to its high content of unsaturated fatty acids. ...
Article
Full-text available
The use of Extracts from the seed of Persea americana Mill (Lauraceae) for ethnotherapy of diseases including cancer, hypertension, blood pressure regulation, diabetes etc, is on the increase in Nigeria, inadequate knowledge of the bioactive compounds in the seeds remains a challenge and this concern gave birth to the present study. In this study, the physicochemical properties and bioactive compounds of avocado seed were determined using standard tests and experiments. The analysis was done in three replicates. The yield of the oil was about (6.9±0.04) %, The results obtained for the physical properties of avocado pear are: Physical state (liquid), Odour (fruity), Colour (dark brown/ brownish red), pH (6.2±0.01), Relative density (0.945±0.02), Electrical conductivity (000uscm-1), Cloud point (8 ± 0.02 o C), Melting point (12 ± 0.02 0 C), Smoke point (167± 0.05 o C), Flash point (180± 0.02 o C), Fire point (241± 0.02 o C), the result of chemical properties of Avocado Pear seed oil assayed include: Acid value (11.78± 0.96 mgKOH/g), Free fatty acid (5.89± 0.96 mgKOH/g) , Peroxide value (43.00± 0.04 mg 2 /Kg), Saponification (m231.41± 1.18gKOH/g). The physico-chemical characteristics of the oil show that it has industrial potentials. 8 major bioactive compounds were detected in the GCMS analysis and they include 2-aziridinyl-ethyl amine, Hydroxylurea, Epinephrine, Benzene ethanamine-3-flouro-β, 5-dihroxyl-N-methyl, Dextroamphetamine, P,α-dimethylphenylethylamine, Cathine and 2-amino-1-propanol. Some of the compounds justify the use of the seed for some ethnomedical therapy. Furthermore, no toxic compound was detected from the analysis; but the inadequate knowledge on the concentration of the compounds present in theses seeds can pose serious health threat on consumers.
... On the other hand, TC-0.4 incorporated sample showed the highest amplitude. Additionally, peak at wavenumber of 1742 cm − 1 decreased in all the samples after 30 days of storage as compared to day 0. In general, peak at 1742 cm − 1 corresponded to carbonyl (C--O) stretching vibration of ester bond in triglycerides (Moigradean, Poiana, & Gogoasa, 2012). The decrease in peak amplitude was related with the increased lipid oxidation as measured by TBARS, representing the amount of malonaldehyde (Fig. 1B). ...
Article
Effects of chitooligosaccharides (COS) or α-tocopherol (TC) or their combinations (COS-TC; 1:1) at different concentrations (0.2 and 0.4 g/L) on physical properties and oxidative stability of shrimp oil-in-water emulsion throughout the storage of 30 days at 25 °C were investigated. During storage of 30 days, COS-TC added sample had the highest turbidity, rheological properties (G′, G″ and viscosity), a* and b* values but the lowest L* value (p < 0.05). Rheological analysis revealed viscous, shear-thinning, and non-Newtonian behavior of emulsion. At day 30, the lowest PV, TBARS, and CD were noticed in those added with COS-TC at 0.4 g/L followed by COS-TC at 0.2 g/L, respectively (p < 0.05). However, TC added sample showed higher oxidation than CON (without addition of antioxidants) (p < 0.05). Based on FTIR spectra, reduction of a peak at 3009 cm⁻¹ and higher amplitude of peak at 2852 cm⁻¹ were observed after storage. Decreases in EPA and DHA could be alleviated by the addition of COS-TC at 0.4 g/L, in which the lowest reduction in PUFA (8.58%) was attained, compared to that of control (19.68%). This was concomitant with the lower droplet size and reduced formation of volatile compounds. Thus, the combination of COS and TC at 0.4 g/L had a strong synergistic effect against oxidation of stored emulsions.
... Coconut oil contained the band peak at 3600-3000 cm −1 belonging to the vibrations of the -OH groups, the band peak 2919 cm −1 and 2850 cm −1 belonging to CH(-CH 2 ) bands at 1742 cm −1 and 1655 cm −1 represented to C = O vibrations. The peak in 1243 cm −1 , 1125 cm −1 1166 cm −1 belonged to the C-O and CH groups and peak in 1459 cm −1 belonged to the C = H bands [42,43]. The new bonds and structural diversity at organo-hydrogels were demonstrated the existence of hydrogen-bond interaction. ...
Article
Full-text available
In this study, six different organo-hydrogel containing Agar-Glycerol (AG) based Coconut Oil (CnO) were synthesized using different crosslinkers to ensure the controlled release of D3 Vitamine and 5-Fluorouracil (5-Flu). Synthesized organo-hydrogels were characterized by FT-IR, Afterwards, swelling behaviors were investigated in ethanol, acetone, ethanol/ID water (1:1), acetone /ID water (1:1) and gasoline environments and different pH. As a result of hemolysis, blood clotting and antioxidant analysis, organo-hydrogels have been shown to have blood compatibility and antioxidant properties. The effects of the initial pH of the solution on the drug release process were investigated. It was observed that the most release occurred at pH 2 and glutaraldehyde crosslinker. Release kinetics models were applied to understand the mechanism of the release system of D3 Vitamine and 5-Flu (anti-cancer) with poly(Agar-co-Glycerol-co-Coconut Oil) (p(AG-co-CnO)) organo-hydrogel. The value of the correlation coefficient (R2) was used as the best model fit indicator of different models and it was determined that the balance data fit the Korsmeyer-Peppas with large R2s and the Higuchi kinetic model. The results showed that the p(AG-co-CnO) organo-hydrogel can be used as a suitable carrier for the controlled release of D3 Vitamin and 5-Flu.
... Hence, the PV of the oils indicated that all samples were fresh. In theory, the VCOs must exhibit a low oxidation rate because of their lower unsaturated fatty acid content [28]. The unsaturated fatty acids react with the oxygen molecules to form peroxides. ...
Article
Since there is a high demand for the virgin coconut oil (VCO) in Iraqi markets due to having consumers recently recognized that VCO has unique nutrition benefits, this study aims to recover the virgin coconut oil (VCO) using four extraction techniques; fermentation VCO (FVCO), dry VCO (DVCO), enzymatic VCO (EVCO), and the chilling and thawing VCO (CVCO) techniques. The fatty acid composition, physicochemical properties and the antioxidant activities of the VCOs were determined and compared to the commercial refined, bleached and deodorized coconut oil (RBD-CO). Physicochemical properties of extracted VCOs were yield, 54–72%; moisture contents, 0.12–0.16%; refractive index 1.45; viscosity, 48–51 cP; free fatty acid, 0.16–0.2 g/100 g; iodine value, 4.17–7,13 g I2/100 g oil; peroxide value 147–259 meq O2/kg oil, and saponification value 254.10–264.04 mg of KOH/g of oil. Fatty acid composition demonstrated that lauric acid had the highest content for all the VCOs with the range of 47.95–48.08%. The DPPH radical-scavenging activity (IC50) for the VCOs were 205.15–248.16 mg/mL and the total phenolic content (TPC) were37.42–68.12 mg GAE/100 mL.
... In order to demonstrate this assumption, the response of gasoline vibrations to SMF was studied by means of FTIR spectroscopy. This technique has been successfully used in previous studies to highlight the characteristics of petroleum compounds [13][14][15]. ...
... Les produits primaires formés sont les hydroperoxydes, qui se décomposent ensuite dans une série de réactions complexes, pour produire des produits secondaires comprenant des alcools et des composés carbonylés qui sont principalement responsables des saveurs off-shore (rancidité) et des odeurs. La valeur du peroxyde donne la quantité de produits d'oxydation primaire[446]. Les résultats des indices de peroxydes des formulations B et C sont affichés au tableau 35. ...
Thesis
La croissance démographique, la consommation incontrôlée des ressources naturelles ainsi que l’activité industrielle jouent un rôle déterminant dans la dégradation de l'environnement mondial. A ce sujet et en se basant sur le concept que les consommateurs partagent la responsabilité de la pollution et de l'épuisement des ressources et leur coût, la mise en oeuvre des ressources renouvelables dans les processus industriels apparait comme une clé décisive. La renouvelabilité, la recyclabilité, la durabilité, la biodégradabilité sont les concepts de base sur lesquels nous pouvons compter pour protéger la nature et l’environnement. Dans ce contexte, une nouvelle approche de la bioraffinage a été développée dans cette thèse, elle a été appliquée à cinq espèces appartenant à 3 familles différentes (Foeniculum vulagre, Cuminum cyminum and Carum carvi (Apiaceae), Salvia hispania (Lamiaceae) et Amaranthus cruentus (Amaranthaceae)). Ces espèces partagent une caractéristique commune, elles peuvent être définies comme Aroma Tincto Oleo Crops (ATOC) puisqu’elles sont une source d'huile végétale et d'huile essentielle (ou de colorant). Notre objectif est donc de déterminer la faisabilité biologique et technologique de l'application du concept ATOC-bioraffinage basé sur le développement, l'optimisation et la production de nouveaux produits biologiques, des nouvelles molécules biosourcées et d'autres technologies innovantes. Notre étude met l'accent sur l'évaluation de divers paramètres influençant le rendement et la qualité de l’huile dans les graines d'ATOC, y compris leurs origines géographiques et le procédé d'extraction, et leur impact sur l'activité biologique des extraits de résidus. La valorisation des huiles pour des applications dans l’industrie cosmétique a été realisée en les utilisant comme (i) additifs dans des formulations de crème hydratante. De plus, l’utilité du tourteau d'extraction comme (ii) substrat pour la fabrication d'agromatériaux par thermopressage et comme (iii) un ingrédient dans des formulations de pain de blé entier a été examinée.
... The oxidative reactions can be influenced by several factors such as light, heat, ionization, traces of metals, and metaloprotein, oxygen reaction with unsaturated lipids, and by chemical, and enzymatic mechanisms such as auto-oxidation, photo-oxidation and lipoxygenases [8]. The coconut oil is highly stable towards atmospheric oxidation [9]. Oxidative stability of oils is the resistance to oxidation during processing and storage [10]. ...
Conference Paper
Full-text available
In the present analysis, tamarind seed oil has been added as an additive to reduce the rancidity of oils. With its addition, the extent of oxidation of vegetable oil and the indicative optimum value of tamarind seed oil required to be added to the vegetable oil sample were studied using standard peroxide value method. The objectives of this study were to compare the peroxide values for vegetable oil samples with and without tamarind oil with passage of time and evaluate the indicative optimum quantity of tamarind oil to be added as an additive to the vegetable oil sample. The results obtained indicates that the addition of tamarind seed oil as an additive to coconut oil has a profound impact on its oxidation process, whereby, the oxidative stability of the vegetable oil sample, can be increased.
... The coconut oil will be stored for a long time to the processing plant and destination country. The coconut oil stored at room temperature for 12 months showed a significant increase in the value of peroxide value, caused by oxidative damage [11]. This might make changes to the constituent components of fatty acids and the active composition in coconut oil. ...
Article
Full-text available
The objective of this study was to screen the quality marker of stored coconut oil on several temperatures. The method used in this researchis a degree date method with sample observations carried out regularly. Coconut oils were stored at 30°C, 40°C and 50°C. The quality of coconut oil after storage were determined with viscosity was measured by Capillary Viscometer SIBATA S0-6818 and carbonyl compounds analysis were analyzed using Liquid Chromatograph Mass Spectrometry (LC/MS). The results showed, viscosity decreased with increasing of temperature. The significant decreased in viscosity occurs at 50°C, which is 23,6138 mm ² /s. Principle component analysis and discriminant analysis (PCA-DA) on compound carbonyl analysis showed the presence that formed at each temperature. A decreased in viscosity and the presence compounds are marker decline in the quality of coconut oil.
... And in another case, oxidative stability of coconut oil has been studied using FTIR spectroscopy. Still, this study only showed peak changes as an effect of oxidation during storage, but it was not precise and lacked a quantitative analysis of FCO (Moigradean, Poiana, & Gogoasa, 2012). Besides this, there is no prominent report regarding the detection of FCO adulteration in PCO using ATR-FTIR spectroscopy along with regression modelling. ...
Article
Attenuated total reflection- Fourier transform infrared (ATR-FTIR) spectroscopy along with multivariate regression modelling was utilized to develop the methodology for classification and quantification of refined, bleached and deodorized (RBD) pure coconut oil (PCO) from its adulterant RBD fried coconut oil (FCO). Principal component analysis (PCA) was applied on 3000-2800 cm⁻¹, and 1800-500 cm⁻¹ and linear discriminant analysis (LDA) was used on selected 13 wavenumbers. Principal components regression (PCR) and Partial least squares regression (PLS-R) models were constructed and compared for normal, 1st, and 2nd derivatives. PLS-R model for the 1st derivative of 1800-500 cm⁻¹ showed the best results for prediction with high precision and accuracy (RPD: 20.03, RE %: 4.288). The lowest limit of detection of FCO in PCO was predicted as 0.5% v/v. This detected concentration is not the constraint of the experiment pursued; instead, it is the lowest concentration of FCO adulteration used in our work. Our findings are only applicable to detection of FCO adulteration at same frying degree while adulteration detection of FCO at different frying degrees is altogether a different adulteration issue. This study provides valuable information to oil industries and the regulatory authorities to build standard guidelines for the detection of oil adulteration.
... Variation in initial PV may be due to difference in grain processing and also oil extraction process. Fresh coconut oil was found to have PV between 0.24 and 0.49 meqO 2 /Kg [22]. According to table 1, although slowly, PV of ASCF samples continually increased during the entire storage period regardless of the storage condition and packaging used. ...
... Based on the results, the oil samples can be classified into moderate oxidation and high oxidation state based on the results calculated for the peroxide values. A product with peroxide values between 5 and 10 meq/kg is at moderate oxidation state above 10 meq/kg is at high oxidation state [2]. Also from the table it could be observed that the rate of peroxidation in the local oils are more compare to the commercial oils with Bushmango oil having a peroxide value of 24.00 meq/kg at 4weeks after frying, so also is melon oil with 12.03 meq/kg in contrast to olive oil with palm oil olein with 9.20 and 8.60 meq/kg respectively at the same period. ...
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Thesis
Bu çalışmada, doğal kaynaklardan (zerdeçal ve patates kabuğundan) elde edilen etanolik ekstraktlar, ticari antioksidanlar (α-tokoferol, β-karoten) ve bazı bileşikler (askorbil palmitat, sitrik asit ve lesitin) kullanılmıştır. Bu maddelerin Ayçiçek yağında antioksidan aktiviteleri tek başlarına ve farklı konsantrasyonlarda çeşitli kombinasyonlar halinde incelenmiştir. Doğal ve yapay antioksidanların ikili ve üçlü kombine kullanımının yanı sıra konsantrasyona bağlı etkilerinin sinerjik ve antagonistik etkileri de araştırılmıştır. Yapılan ön denemeler neticesinde yüksek antioksidan aktivite gösteren bileşikler ve bunların kombinasyonları oluşturulmuş, ardından peroksit değerleri, p-anisidin değeri, toplam oksidasyon değeri, indüksiyon süresi, DPPH radikal tutucu aktivite ve % sinerji oranları belirlenmiştir. 65oC’de 6 gün depolama sonucu peroksit değerleri (meq O2/kg) sonucuna göre, patates kabuğu ekstraktı (40.96) tek başına kullanıldığında, zerdeçal ekstraktına (127.67) göre daha güçlü antioksidan aktivite sergilemiştir. Patates kabuğunda bu etkinin oluşmasında polar paradoksun da payı olduğu düşünülmektedir. Bununla beraber, askorbil palmitatın (25.72 meq O2/kg) incelenen tüm antioksidanlardan daha üstün antioksidan aktiviteye sahip olduğu görülmüştür. α-tokoferol içeren antioksidan karışımlarında başarılı sonuçlar elde edilememiştir. Zerdeçal ekstraktının (5000 ppm) askorbil palmitat (1000 ppm) ile birlikte kullanımı çok güçlü sinerjik etki (%94.95) oluşturmuştur. Bu örnek aynı zamanda en yüksek indüksiyon süresine (7.6s) ve DPPH radikal tutucu aktiviteye (%69.8) sahiptir. Patates kabuğu ekstraktı ile oluşturulan kombinasyonlar kuvvetli antioksidan aktivite göstermiştir. Zerdeçal çeşitli fonksiyonel bileşikler içeren bir kök bitkisi olup doğal bir antioksidan olarak kabul edilen askorbil palmitat ile kombinasyonu en yüksek antioksidan aktiviteye sahiptir. Elde edilen bulgular ışığında, bir atık niteliğinde olan patates kabuğunun, lipit oksidasyona karşı etkili bir şekilde değerlendirilebileceği düşünülmektedir.
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Conference Paper
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Adulterated foods are causing health-related issues since there is no rapid method available for the detection of food fraud. The main objective of this study is to determine the feasibility of using near-infrared (NIR) spectroscopy in differentiating pure palm oil from palm oil adulterated with recycled cooking oil in varying concentrations. The deep-frying process was carried out for chicken nuggets and French fries as fried items using palm oil as a frying medium to produce used frying oil. The refining and bleaching process was applied to used frying oil to generate recycled cooking oil. Adulterated samples were developed with different concentrations of recycled cooking oil in pure palm oil (1%, 2%, 3%, 5%, 10%, 15%, 20%, 30%, 40% and 50%). Principal component analysis was applied to analyze the distribution of pure and adulterated palm oil samples. The classification accuracy of the proposed method using handheld NIR spectroscopy in distinguishing adulterated samples of lower concentrations was found to be low (below 50%). Adulterated palm oil samples of recycled cooking oil (RCO) concentration (15% and above) were found to show classification accuracy of 100% when detected through handheld NIR spectroscopy.
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The purpose of this research was to determine the effect of high‐intensity ultrasound (HIU) on physical properties, degree of oxidation, and oxidative stability of structured lipids (SLs). Caprylic acid (C) and stearic acid (S) were incorporated into menhaden oil using Lipozyme® 435 lipase to obtain five samples: (1) LC 20 (menhaden oil with 20% of C), (2) LC 30 (menhaden oil with 30% C), (3) LS 20 (menhaden oil with 20% S), (4) LS 30 (menhaden oil with 30% S), and (5) Blend C (menhaden oil with 16.24% C and 13.04% S). Samples were crystallized for 90 min at the following temperatures: (1) LC 20 at 15.5°C, (2) LC 30 at 17.5°C, (3) LS 20 at 24°C, (4) LS 30 at 30°C, and (5) Blend C at 18.0°C, and HIU was applied at the onset of crystallization. Physical properties, degree of oxidation, and oxidative stability were evaluated in sonicated and nonsonicated samples. All SLs had statistically higher G′ after sonication. Sonicated LS 30, LC 30, and Blend C had a higher melting enthalpy than the nonsonicated ones, while enthalpy values in sonicated LS 20 and LC 20 samples were not statistically different than the nonsonicated ones. No significant difference between sonicated and nonsonicated samples was observed in peroxide values (1.2 ± 0.1 meq/kg, p > 0.05) and in the oxidative stability index (6.3 ± 0.2 h, p > 0.05). These results showed that HIU was effective at changing physical properties without affecting the oxidation of the samples.
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The mechanical extraction on the yield and quality of avocado oil extracted from different fruit varieties were investigated in this study. Batches of various varieties of ripen avocado in Burundi were processed in an oil mill located in the Gitega Region. Avocado oil was extracted considering the malaxation step carried out with and without the enzymes addition. Avocado pulp achieved by malaxation at 30°C for 90 min presented the highest yield and get the lessen acidity and peroxide values. Under the conditions applied in this study (dilution ratio between avocado paste and purified water at 1: 0.5 and malaxation temperature below 36°C), the addition of pectolitic and amylolytic enzymes did not reveal to increase the yield to such extent as to justify the cost of the treatment. According to what stated for classification of olive oils in EVO and VO categories, the results of chemical and sensorial indices allowed classifying most of the avocado oils obtained from malaxation without enzyme addition in the EVO category.
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Characteristics of oil blends has been produced from red palm oil (RPO) and palm kernel olein (PKOo) with seven ratios with a total of 100, namely A (0:100), B (25:75), C (40:60), D (50:50), E (60:40), F (75:25) and G (100:0) v/v investigated with randomized complete block design. The result showed that different of ratio levels RPO and PKOo have some effects on peroxide value, saponification value, melting point, cloud point and β-carotene content from RPO-PKOo oil blends, but has not effect on free fatty acid content. Higher level of PKOo content on formulas oil blends were decreased of saponification value and melting point, but was increased of cloud point. The best of RPOPKOo oil blends has been obtained at ratio 50:50 (v/v), with 459.52 ppm β-carotene, 1.35 meq/kg peroxide value, 0.09 % free fatty acid, 202.60 saponification value, 24.15 oC melting point and 7.15 oC cloud point. Fatty acids composition were 1.24 % capric acid, 29.00 % lauric acid, 10.09 % miristic acid, 23.10 % palmitic acid, 5.84 linoleic acid, 27.30 % oleic acid and 3.43 % stearic acid. Keywords: Red palm oil, palm kernel olein, oil blends, chemical and physical properties ABSTRAK Sifat-sifat minyak campuran yang dihasilkan dari red palm oil (RPO) dan palm kernel olein (PKOo) dengan tujuh tingkat rasio yang totalnya 100, yaitu A (0:100), B (25:75), C (40:60), D (50:50), E (60:40), F (75:25) dan G (100:0) (v/v) dikaji menggunakan rancangan acak lengkap kelompok. Hasil penelitian menunjukkan bahwa rasio RPO:PKOo mempengaruhi angka peroksida, angka penyabunan, melting point, cloud point dan kadar β-karoten dari minyak campuran RPO-PKOo yang dihasilkan, namun tidak mempengaruhi kadar asam lemak bebas. Peningkatan jumlah PKOo yang ditambahkan dalam minyak campuran RPO-PKOo, akan menurunkan angka penyabunan dan melting point, namun akan menaikkan cloud point. Produk minyak campuran RPO-PKOo terbaik diperoleh pada rasio 50:50 (v/v), dengan kadar β-karoten 459,52 ppm, angka peroksida 1,35 meq/kg, asam lemak bebas 0,09 %, angka penyabunan 202,60, melting point 24,15 oC dan cloud point 7,15 oC, serta komposisi asam lemak (kaprat 1,24 %, laurat 29,00 %, miristat 10,09 %, palmitat 23,10 %, linoleat 5,84 %, oleat 27,30 % dan stearat 3,43 %). Kata kunci: Red palm oil, palm kernel olein, minyak campuran, sifat kimia, sifat fisika
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This research aimed to examine the effect of high‐intensity ultrasound (HIU) on the oxidation of soybean oil (SBO). Samples (5, 100, and 250 g) were sonicated at 25 ºC using various sonication conditions: power level (setting 1, 5, and 9), tip size (12.7, 3.2, and 2 mm), and duration (5, 10, and 60 s). After sonication, the degree of oxidation of samples (sonicated and non‐sonicated SBO) were analyzed using peroxide value (PV), oil stability index (OSI), and volatile compounds. Sonication was applied to obtain a range of absolute power (0‐123.5 W), power density (0‐14.2 W/cm3), and power intensity (0‐1,120 W/cm2) values. The highest power density and power intensity were obtained with the highest HIU setting with the 3.2 mm tip. The highest power was obtained when HIU was applied using 12.7 mm tip and setting 9 in 250 g of sample. No significant difference (P>0.05) was observed in PV (0.20±0.01 mEq/kg) nor OSI (10.05±0.04 h,) among the various sonication conditions tested. In addition, no differences were observed in the volatile compounds obtained. These results show that HIU can be used under mild sonication conditions such as the ones needed to change physical properties of lipids without causing oxidative deterioration.
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