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Cooking can adversely affect chemical characteristics of edible oils. The purpose of this paper is to determine biochemical changes due to cooking in commonly used Indian fats and oils through an experimental study.

Changes in chemical properties of various edible oils [Indian ghee (clarified butter), hydrogenated oil, coconut oil, mustard‐rapeseed oil, groundnut oil, soyabean oil, cottonseed oil and sunflower oil] were studied. Oils were subjected to various cooking methods (shallow frying, sautéing, single deep frying and multiple deep fryings) using an inert substance. Peroxide content was estimated as index of fatty‐acid oxidation, free fatty acids, iodine value for determination of fatty‐acid unsaturation and trans‐fatty acids at baseline and after cooking using colorimetric and gas‐liquid chromatography methods. Three samples were analyzed for each process (n = 144). Significance of change was determined using t‐test.

There was a significant increase in peroxide content (mEq/L) of Indian ghee from 1.83±0.03 at baseline to 4.5–6.6 by different cooking methods, hydrogenated oil (0.45±0.07 to 1.7–8.5), coconut oil (1.01±0.01 to 3.2–9.2), mustard‐rapeseed oil (0.90±0.01 to 2.1–5.3), groundnut oil (0.96±0.01 to 1.9–3.7), soyabean oil (0.86±0.02 to 1.9–3.4), cottonseed oil (0.71±0.01 to 2.9–6.4) and sunflower oil (1.09±0.01 to 2.3–10.2) (p<0.05). Free fatty acid content (g/100 g) was in undetectable amounts in all the fats at baseline and increased in Indian ghee (0.16–0.22), hydrogenated oil (0.09–0.23), coconut oil (0.09–1.39), mustard‐rapeseed oil (0.07–0.19), groundnut oil (0.09–0.18), soyabean oil (0.06–0.12), cottonseed oil (0.09–0.22) and sunflower oil (0.08–0.13). Trans‐fatty acids increased from 0.1% at baseline to 14.5% after sautéing and shallow frying and 15.8–16.8% after deep frying in hydrogenated oils (p<0.01). The iodine value decreased, indicating a decrease in unsaturated fats, insignificantly. The largest amount of oxidation was observed by shallow frying and free‐fatty‐acid formation by multiple deep frying. Hydrogenated, coconut and sunflower oils were the most susceptible to oxidation and soyabean oil the most resistant. Single deep frying caused the least changes in chemical composition of various fats and oils. Indian cooking practices significantly increase the peroxides, free fatty acids and trans‐fatty acids in edible oils and fats. Single deep frying appears to be the least harmful method and soyabean oil the least susceptible to degradation.

The paper offers an experimental study to determine biochemical changes due to cooking in commonly used Indian fats and oils.

The purpose of this study is to compare the oxidative stability of non‐hydrogenated cottonseed oil with that of the partially hydrogenated oils commonly used as a deep‐fat frying medium by the restaurant industry when used to prepare French fries in order to reduce trans‐fatty acids.

Stability characteristics of non‐hydrogenated cottonseed oil and two hydrogenated oils, canola and soybean, were evaluated in deep‐fat frying applications. French fries were analyzed for total polar compounds, and the oils were analyzed for iodine, peroxide, p‐anisidine and totox values, and free fatty acids.

Canola and soybean oil had significantly lower iodine values than cottonseed oil. Free fatty acid values were not significantly different among the oils (0.256 per cent oleic acid). Initially cottonseed oil had higher peroxide, p‐anisidine, and totox values compared with canola and soybean oil. However, as days of frying increased, values trended closer together. Total polar compounds were similar. All oil types were comparable in terms of their stability characteristics under the conditions used in this study.

Research with additional food product and under more stressful conditions would be beneficial.

Hydrogenation increases trans‐fatty acid content. Consumption of trans‐fatty acids has been associated with increased risk of heart disease. Non‐hydrogenated cottonseed oil may be a viable alternative to popular hydrogenated oils currently used in the restaurant setting.

Restaurants are being pressured by health officials to choose healthier oil. This research article can help restaurants make an informed choice.

This paper aims to characterize the pumpkin (Cucurbita sp) seed oil from the varieties Nova Caravela, Mini Paulista, Menina Brasileira (Cucurbita moschata) and Moranga de Mesa (Cucurbita maxima) as to their physicochemical properties, vitamins and fatty acid and triacylglycerols profiles.

The oils were extracted from oilseeds by the Bligh and Dyer (1959) method, and chemical characterization was performed by using standard methods for oils and fats. The vitamin A and E content, fatty acid profile and triacylglycerols profile also were determined.

About the chemical properties, the oils showed values within the range for edible vegetable oils. The oil from variety Nova Caravela stood out for presenting better quality, as it showed lower values of free fatty acids, acidity and peroxides. However, it was found that the Moranga de Mesa oil was the most unsaturated, due to the high refractive and iodine index, and was also reported to have lower oxidative stability. Among the unsaturated fatty acids, ranging from 70 to 78 per cent of the total obtained, linoleic and oleic acids stood out, while among the saturated ones, palmitic and stearic did.

These seeds are rich in high-quality lipids; therefore, their use could help to reduce the amount of waste produced in the industries, and consequently reduce environmental contamination. This study showed that the seeds could be used as a raw material for oil extraction, and also could be used for developing functional foods instead of being discarded.

This study provides valuable information about the quality and fatty acid contents of pumpkin seed oils consumed in Brazil.

Purpose: Evidence of adverse health effects of artificial trans fatty acids (TFAs) have accumulated since 1990s, yet TFAs are widely used by several food manufacturers around the world. This review aimed to: ascertain the available evidence of the known unfavourable biochemical properties of artificial TFAs, their metabolic functions and health consequences; estimate their average intake levels and trends in different countries in order to critically evaluate whether more action is required to eliminate them from the diet. Methodology: The published evidence was searched by employing: Medline, Pubmed, InterScience, BioMed Central and Annual Reviews. Findings: With reference to human health, evidences from epidemiological, retrospective and observational studies revealed that the consumption of TFAs could outweigh the health risks posed by saturated fat consumption. The main health concerns included unfavourably altered blood cholesterol concentrations, insulin resistance, foetal brain and neural disturbances, proinflammatory and carcinogenic responses. Great variation exists in the global trends of industrial TFAs intake, being low in Mediterranean region, Japan and Scandinavia and high in parts of United States of America and Iceland. Besides the intense use of TFAs by food manufacturers and in eateries, the use of TFAs in food products is often poorly regulated and ill‐informed to consumers. Value: Since competitive alternatives to TFAs have made them non‐mandatory a broad public health intervention at government level to regulate or completely eliminate them from the national diet is warranted.

To evaluate the performance of the compatibiliser of epoxidised soyabean oil‐free fatty acid prepared on the NBR/EPDM blends compared with maleic anhydride and also to explore the effect of loading the compatibiliser NBR/EPDM rubber blend with unmodified and modified polypropylene fibres on the mechanical properties of the blend.

To achieve desirable rheological and physico‐mechanical properties of NBR/EPDM rubber blend, various compositions were made by incorporating different doses of the compatibiliser of epoxidised soyabean oil‐free fatty acid prepared and maleic anhydride to form NBR/EPDM blends. The effect of loading the compatibiliser rubber blend with unmodified and modified polypropylene fibres on the mechanical properties of the blend was investigated.

The incorporation of epoxidised soyabean oil‐free fatty acid or maleic anhydride into NBR/EPDM blend greatly enhanced their compatibility improved the rheological, as well as physical properties of rubber blends. The addition of NBR to EPDM improved the motor oil swelling resistance of EPDM. Blending of the two individual rubbers without a compatibiliser generally exhibited a non‐synergistic effect with respect to the physical properties. The strain energy, tensile strength, Young's modulus and strain at yield varied linearly with composition in the presence of compatibiliser, but deviated from linearity in the absence of compatibiliser. Reinforcement of the NBR/EPDM blend with modified polypropylene fibres enhanced the physical properties more significantly than with the unmodified ones.

The compatibiliser of epoxidised soyabean oil was prepared by reacting in situ soyabean oil‐free fatty acid with per‐acetic acid.

The method developed provided a simple and practical solution to improving the rheological and physico‐mechanical properties of the NBR/EPDM rubber blend.

The method for enhancing rheological and physico‐mechanical properties of NBR/EPDM rubber blend loaded with modified polypropylene fibres was very important and showed a synergistic effect and could find numerous applications in the rubber and plastic industries.

IN THE DIVISION of organic chemicals into aromatics (benzene derivatives) and aliphatics (methane derivatives or fatty compounds), it has been found with reference to the last‐named that oleic acid is the most widespread of all the natural fatty acids. This acid accounts for more than 30 per cent of total fatty acids found in combination in many fats and oils, while its presence has been noted in all the natural fats and oils known to man.

The objective of this work is to study the fatty acid profile of coconut oil in the kernel in relation to maturity of the nut and season of fertilization in five selected varieties of coconut.

The coconut oil from the popular cultivars/hybrids were studied in post‐monsoon, pre‐monsoon and monsoon seasons at 7, 8, 10 and 12 months after fertilization.

Nuts that fertilized in the post monsoon season were found to have higher oil contents. Of the five varieties, COD×WCT had lesser amounts of caprylic, capric and lauric acids and greater amounts of the long chain fatty acids. Though significant differences were observed in fatty acid concentrations in nuts differing in their variety and season of tagging, the trend remained the same.

The study helps to ensure the safety of the usage of coconut oil as dietary oil, from the nature of fatty acids present.

This paper aims to review the chemical composition and industrial benefits of oil extracted from dikanut kernels.

Several literatures on chemical composition of dikanut kernels, methods of oil extraction from dikanut kernels and chemical composition of oil extracted from dikanut kernels were critically reviewed.

The review showed that proximate composition of dikanut kernels ranged from 2.10 to 11.90 per cent, 7.70 to 9.24 per cent, 51.32 to 70.80 per cent, 0.86 to 10.23 per cent, 2.26 to 6.80 per cent and 10.72 to 26.02 per cent for moisture, crude protein, crude fat, crude fibre, ash and carbohydrate contents, respectively. The methods of oil extraction from dikanut kernels include soxhlet extraction method, novel extraction method, enzymatic extraction method and pressing method. The quality attributes of dikanut kernel oil ranged from 1.59 to 4.70 g/100g, 0.50 to 2.67 meq/Kg, 4.30 to 13.40 g/100g, 187.90 to 256.50 mg KOH/g and 3.18 to 12.94 mg KOH/g for free fatty acid, peroxide value, iodine value, saponification value and acid value, respectively. Also, the percentage compositions of oleic, myristic, stearic, linolenic, palmitic, lauric, saturated fatty acids, monosaturated fatty acids and polyunsaturated fatty acids ranging from 0.00 to 6.90, 20.50 to 61.68, 0.80 to 11.40, 0.27 to 6.40, 5.06 to 10.30, 27.63 to 40.70, 97.45 to 98.73, 1.82 to 2.12 and 0.27 to 0.49 respectively. The results showed that dikanut kernels has appreciable amount of protein, carbohydrate and high level of fat content while oil extracted from dikanut kernels have high saponification value, high myristic acid and high lauric acid.

There are scanty information/published works on industrial products made from oil extracted from dikanut kernels.

The review helps in identifying different methods of extraction of oil from dikanut kernels apart from popular soxhlet extraction method (uses of organic solvent). Also, it helps to identify the domestic and industrial benefits of oil extracted from dikanut kernels.

The review showed that oil extracted from dikanut kernels could be useful as food additive, flavour ingredient, coating fresh citrus fruits and in the manufacture of margarine, oil creams, cooking oil, defoaming agent, cosmetics and pharmaceutical products.

Extraction and purification of Hypophthalmichthys molitrix fish oil by urea complex formation were made at −5, +1 and +5 ^○C, respectively. Omega‐3 polyunsaturated fatty acids (PUFA) have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega‐3 PUFA.

Fish oil was extracted by Bligh and Dyer method from the muscle tissue and after, the PUFA concentrates produced by urea complexation and the oil samples were stored at −70 ^○C. The observed results show that the rate of omega‐3 extraction has been increased while saturated and long chain monosaturated fatty acids decreased during this process.

Eicosapentaenoic acid (EPA) has a higher tendency to form urea adducts than the other two major n‐3 PUFAs, especially at low temperatures. The optimum temperature for maximum recovery of EPA is about 1 ^○C. The amount of extracted omega‐3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1 ^○C, 36.82 per cent wt at +5 ^○C and 22.53 per cent wt at −5 ^○C of total extracted oil.

Omega‐3 PUFA have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega‐3 PUFA. In order to reduce the risk of cardiovascular diseases, emphasis has now been placed on the increased consumption of fish and fish products which are rich in PUFA.

The amount of extracted omega‐3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1 ^○C, 36.82 per cent wt at +5 ^○C and 22.53 per cent wt at −5 ^○C of total extracted oil. Due to the low price of H. molitrix in comparison to other ocean fish sources, as well as, its availability in all seasons, higher level of ω3‐fatty acids, H. molitrix species has a good potential for ω3‐fatty acids production by extraction and subsequent purification.

Hempseed oil is a valuable emerging food product with recognized health positivity due to its composition. The paper aims to propose a multi-methodological chemical profiling of nine organic hempseed oil samples (different brands and prices) from the retail market, followed by multivariate data analysis.

Fatty acids, tocopherols, squalene, total carotenoids content, phenolic compounds, total phenolic content and anti-radical activity (DPPH• and ABTS•+ assays) were determined through chromatographic and spectrophotometric techniques. Multivariate (explorative and discriminant) analyses were applied to the profiling results to classify samples according to information claimed on the label, i.e. geographical origin (EU vs. non-EU), extraction procedure (cold-pressed vs. not cold-pressed) and price (lower or higher than 10 € per 250 mL).

The chemical analysis confirmed the 3 to 1 ?-6:?-3 ratio and the excellent content in antioxidant species. However, no specific trend of results can be stressed. PCA (after variables selection) highlighted a natural grouping of samples, so three discriminant analyses were performed: kNN, Naïve Bayes and LDA. The best classification efficiency was reached for the extraction procedure verification (93–100% correct classification), followed by geographical origin (83–94%) and prices (81.6–90%).

The integrated approach of chemical profiling coupled with multivariate analyses allowed the assessment of label information of the analyzed organic hempseed oil samples, despite the wide heterogeneity of the selected samples.