Effect of heating process on oil yield and fatty acid composition of wheat germ
Main Article Content
Keywords
wheat germ, heat treatment, oil content, fatty acid composition, linoleic, GC
Abstract
In this study, fatty acid composition, antioxidant activity, total phenol and oil content of heat-treated wheat germs were investigated. Results of control samples were compared with heated wheat germs at different temperatures (100, 120, 150 and 180 °C) and times (5, 8 and 11 min). The maximum yield was obtained when heated at 120 °C/11 min with 7.293% and 120 °C/8 min with 7.256%, while the minimum oil content was observed at 100 °C/11 min with 5.794%. Linoleic, oleic acid and palmitic acids were the major fatty acids of wheat germ oil. The most dominant fatty acids of control samples were linoleic (58.382%), oleic acid (18.554%), palmitic acid (12.926%), and linolenic acid (6.848%). The fatty acid composition of wheat germ oil was not significantly affected by the heating treatment. On the other hand, a decrease was observed in antioxidant activity of heated samples. Wheat germ had the highest total phenol content.
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