Zhang Zhenshan, Xie Xinyi, Jia Huijie, Le Wu, Xiang Pengfei
College of Food Science and Technology, Henan University of Technology, Zhengzhou 450001, PR China.
Food Chem X. 2024 Aug 12;23:101733. doi: 10.1016/j.fochx.2024.101733. eCollection 2024 Oct 30.
To investigate the effect of freeze-thaw (FT) process on the yield and quality of tiger nut oil, tiger nuts were subjected to 0-12 cycles of FT treatment. Results indicated that FT treatment ruptured the cell structure of tiger nut, resulting in an increase in oil yield. Acid value (2.09-2.42 mg KOH/g) and peroxide value (0.40-0.42 mmol/kg) increased with the number of FT cycles, but the increments were small. Likewise, slight differences in fatty acid composition and thermal properties between control and FT-treated samples were observed. FT treatment remarkably increased the bioactive components (e.g., vitamin E, sterols, chlorophyll and carotenoids) in the oil and extended the oxidation induction time from 1.2 to 5.57 h. FT treatment altered the volatile composition of tiger nut oil, increasing the relative content of heterocycles and pyrazines such as 2-methoxy-4-vinylphenol, trimethylpyrazine and tetramethylpyrazine. It was suggested that FT treatment prior to oil extraction was beneficial to improve the oil yield and quality.
为研究冻融（FT）处理对油莎豆油得率和品质的影响，对油莎豆进行了0至12次冻融循环处理。结果表明，冻融处理破坏了油莎豆的细胞结构，导致油得率增加。酸值（2.09 - 2.42毫克氢氧化钾/克）和过氧化值（0.40 - 0.42毫摩尔/千克）随冻融循环次数增加而升高，但增幅较小。同样，对照样品和冻融处理样品之间在脂肪酸组成和热性质方面也观察到细微差异。冻融处理显著增加了油中的生物活性成分（如维生素E、甾醇、叶绿素和类胡萝卜素），并将氧化诱导时间从1.2小时延长至5.57小时。冻融处理改变了油莎豆油的挥发性成分，增加了杂环化合物和吡嗪类（如2 - 甲氧基 - 4 - 乙烯基苯酚、三甲基吡嗪和四甲基吡嗪）的相对含量。研究表明，在油提取之前进行冻融处理有利于提高油得率和品质。
