939 resultados para Oils and fats, Edible Deterioration Testing


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Rapeseed (canola) and other monounsaturated fatty acid (MUFA)-rich oils are viewed as good candidates to replace, at least partially, the fish oil normally included in aquaculture feeds (aquafeeds). In fact, their utilization as a dietary lipid source for aquatic animals has some advantages over other readily available terrestrial alternative oils and fats; however, this is not without difficulties. MUFA are, indeed, easily digestible and a good source of available energy, and their deposition into fish flesh is considered to be less detrimental than other fatty acid classes, from a human nutritional viewpoint. This chapter attempts to review the principal information available regarding the utilization of MUFA-rich vegetable oil (VO) in aquaculture feed. Initially the chapter focuses on the rapeseed oil eRa) industry, agronomy, quality improvement, processing, and uses, and the main chemical and physical characteristics of rapeseed oil and other MUFA-rich va such as olive oil, peanut oil, and rice bran oil, amongst others. Following this, the potential advantages and challenges of using these alternative oils in the aquaculture feed industry are presented and discussed.

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α-Linseed, camelina. perilla, and echium oils are n-3 C18 polyunsaturated fatty acid (PUFA)-rich vegetable oil sources viewed as favorable replacements to fish oil in aquaculture feed (aquafeed) production in consideration of their high (α-linolenic acid (ALA, 18:3n-3) and/or stearidonic acid (SDA, 18:4n-3) contents and potential for subsequent bioconversion to n-3 long-chain polyunsaturated fatty acids (LC-PUFA) in farmed aquatic species. While the total production of these oils is currently low in comparison with that of other terrestrial oil sources, their distinct fatty acid composition and high n-3 to n-6 ratio deliver a unique substitute to fish oil in aquafeeds, presently unparalleled in other alternative terrestrial oil sources. The dietary inclusion of these oil sources has therefore attracted significant research attention, resulting in a multitude of investigations across a broad range of aquatic species (finfish and crustaceans). Generally, providing that the essential fatty acid (EFA) requirements of the species under investigation were met and an adequate level of fish meal was present in the diet, it was found possible to replace 100% and 60-70% of the dietary fish oil component for freshwater and marine species, respectively, with minimal impact on growth performance indices. However, the substitution of fish oil with n-3-rich vegetable oils and/or vegetable oil blends resulted in substantially reduced concentrations of health-promoting eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) in the edible portion of the farmed species. This chapter provides an overview of the use of n-3 PUFA-rich vegetable oils and/or vegetable oil blends for use in aquafeeds. In particular, key aspects of oil production, processing, and refinement will be presented, and individual differences pertaining to the physical, chemical, and nutritional characteristics of the oil types will be highlighted. Following on from this, a summary of the key findings relevant to n-3 PUFA-rich vegetable oil inclusion in aquafeeds will be discussed, with particular emphasis placed on growth performance and nutritional modification.

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Vegetable oils and their derivatives, like biodiesel, are used extensively throughout the world, thus posing an environmental risk when disposed. Toxicity testing using test organisms shows how these residues affect ecosystems. Toxicity tests using earthworms (Eisenia foetida. are widespread because they are a practical resource for analyzing terrestrial organisms. For phytotoxicological analysis, we used seeds of arugula (Eruca sativa and lettuce (Lactuca sativa. to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with four different periods of biodegradation in soil: zero days, 60 days, 120 days and 180 days. The studied contaminants were soybean oil (new and used) and biodiesel (B100). An evaluation of the germination of both seeds showed an increased toxicity for all contaminants as the biodegradation occurred, biodiesel being the most toxic among the contaminants. on the other hand, for the tests using earthworms, the biodiesel was the only contaminant that proved to be toxic. Therefore, the higher toxicity of the sample containing these hydrocarbons over time can be attributed to the secondary compounds formed by microbial action. Thus, we conclude that the biodegradation in soil of the studied compounds requires longer periods for the sample toxicity to be decreased with the action of microorganisms.

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Vegetable oils are important sources of essential fatty acids. It is, therefore, important to characterize plant species that can be used as new oil sources. This study aimed to characterize the oils from guariroba (Syagrus oleracea), jeriva (Syagrus romanzoffiana), and macauba (Acrocomia aculeata). The physicochemical characterization was performed using official analytical methods for oils and fats, free fatty acids, peroxide value, refractive index, iodine value, saponification number, and unsaponifiable matter. The oxidative stability was determined using the Rancimat at 110 degrees C. The fatty acid composition was performed by gas chromatography. The results were submitted to Tukey's test for the medium to 5% using the ESTAT program. The pulp oils were more unsaturated than kernel oils, as evidenced by the higher refractive index and iodine value, especially the macauba pulp oil which gave 1.4556 and 80 g I(2)/100 g, respectively, for these indices. The kernel oils were less altered by oxidative process and had high induction period, free fatty acids below 0.5%, and peroxide value around 0.19 meq/kg. The guariroba kernel oil showed the largest induction period, 91.82 h.

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Purpose: The purpose of this paper is to characterize oils extracted from Bertholletia excelsa, Lecythis pisonis, Dipteryx lacunifera, Carya illinoensis and Juglans regia, regarding their characterization and fatty acid profile. Design/methodology/approach: The oils were extracted from oilseeds by cold pressing and physico-chemical characterization was performed by using standard methods for oils and fats. The oxidative stability and fatty acid profile also were determined. Findings: According to the results, the physico-chemical properties of oils from nuts and walnuts were comparable to those of good quality conventional oils. The oil seeds are a good source of unsaturated fatty acids, especially oleic and linoleic acids. Research limitations/implications: Implies the identification of fatty acid profile and physico-chemical properties of oils extracted from nuts and walnuts, and to prevent certain types of diseases. Originality/value: The paper identifies a new source of essential fatty acids extracted from oilseeds. © Emerald Group Publishing Limited.

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Vegetable oils are used in the industry of processed food, including deep-fat frying. This work determined data on the thermophysical properties of cotton, canola, sunflower, corn, and soybean oils. Thermal conductivity, heat capacity, density, and viscosity were measured within the temperature range of 299.15-433.15 K. The data showed that the temperature influenced the thermophysical properties of the oils studied. The developed correlations could be used to predict these properties within the range of temperatures studied. © 2013 Copyright Taylor and Francis Group, LLC.

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Introduction: There are few studies assessing overall diet and food patterns of the oldest population. Objectives: To examine food groups consumption (grams and servings) and their compliance with the dietary guidelines in community-dwelling very old Spanish adults. The relationship with the risk of malnutrition was also studied. Methods: Within the cross-sectional health study of elderly people of Villanueva de la Cañada (Madrid, Spain), in 98 non-institutionalized elders aged ≥ 80 years (66% women) food consumption was calculated from a 24-hour dietary recall and nutritional risk was assessed by Mini Nutritional Assessment (MNA). Statistical significance was evaluated at 95% confidence level (p < 0.05). Results: Men consumed significantly higher amounts of snacks/pickles and alcoholic beverages. The consumption of cereals/grain products (2 servings/day), vegetables (1.5 servings/day) and meat, fish, eggs (1.4 servings/day), was below desirable levels. As nutritional status got worse, fruit consumption was significantly smaller (p = 0.039). Relatively weak but highly significant correlations were found between MNA and oils/fats, fruits and alcoholic beverages. After adjustment for energy intake, oils and fats and fruits associations disappeared whereas a negative association between milk/dairy products and MNA was found. Conclusions: Dietary patterns of the elderly population of Villanueva are departing from the traditional Mediterranean diet and though adequate consumption of fruits, milk/dairy products, oils/fats and sugar/confectionery has been achieved, cereals/grain products, vegetables and the meat,fish,eggs group consumption was below the desirable levels. Deterioration of the nutritional status coincided with a reduction in the consumption of all food groups except for ready meals and milk/dairy products whose consumption increased. Further research on the influence of fruit, milk/dairy products, wine and olive oil consumption on nutritional status is required.