responsible for the oxidation of oil to produce off-flavor compounds. Soybean oil also contains photosensitizers such as chlorophyll that produce singlet oxygen in the presence of light (22). Singlet oxygen can directly react with fatty acid double bonds and oxidize the fatty acids at a rate 1,500 times that of autoxidation (23,24). Analysis of head-space has shown that 2,4-decadienals, 2-heptenal, 2,4-heptadienal, pentane, and hexanal are the principal volatile compounds formed from oxidized soybean oil (25). The flavor characteristics of oxidized soybean oil have been described as grassy or fishy, but a single volatile flavor compound that gives unique grassy or fishy flavor in oxidized soybean oil has not been identified (26). However, trans-2-hexenal and 2,6-nonadienal have been reported to give general grassy flavors, whereas dec&-trans-2,cis-A,trans-1-trienol and oct-l-en-3-one have been linked to fishy flavors (13).

Vegetable oils such as corn, cottonseed, peanut, coconut, safflower, and olive oil, as well as animal fats such as lard and beef tallow provide unique flavor characteristics to foods. Oil processing, which involves the three steps of refining, bleaching, and deodorization, removes impurities that contribute to the development of undesirable flavors. Olive oil, which contains 50 to 83% oleic acid, is popular in the United States as a result of the positive nutritional implications of monounsaturated fats. The flavor compounds of olive oil have been separated and identified by gas chromatography-mass spectrometry. Hexanal, trans-2-hexenal, 1-hexanol, and 3-methylbutan-l-ol, which are formed by autoxidation, are the principal volatile compounds of olive oil. Its flavor can be influenced by many factors such as climatic and soil conditions, the maturation process of the olive, and storage conditions (27). Although many volatile compounds have been identified, specific chemical compounds that are responsible for olive oil's flavor have not been determined. Safflower oil, which contains 78% linoleic acid, possesses the highest content of polyunsaturated fatty acid of all the commercial oils. The high content of linoleic acid increases the susceptibility of the oil to oxidation, resulting in the formation of off-flavor compounds (28). Cottonseed oil, which contains 18% oleic acid and 53% linoleic acid, is mainly used in restaurants for frying potato chips, seafood, and snacks. The bland flavor of cottonseed oil reportedly does not mask the flavor of the product nor does it revert during deep-fat frying (29).

Homemade Pet Food Secrets

Homemade Pet Food Secrets

It is a well known fact that homemade food is always a healthier option for pets when compared to the market packed food. The increasing hazards to the health of the pets have made pet owners stick to containment of commercial pet food. The basic fundamentals of health for human beings are applicable for pets also.

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