挤压稳定化对不同贮藏时间米糠制备米糠毛油品质的影响

以不同贮藏时间的米糠为原料,研究米糠挤压稳定化处理对米糠毛油品质的影响。结果表明:相比米糠未稳定化制备的米糠毛油,米糠挤压稳定化处理增加米糠毛油的酸值和过氧化值;随着米糠贮藏时间的延长,米糠挤压稳定化处理与未稳定化处理制备米糠毛油酸值和过氧化值相差幅度增加;米糠挤压稳定化处理对米糠毛油的脂肪酸组成影响较小,仅亚麻酸含量显著下降,米糠挤压稳定化处理对米糠毛油碘值和皂化值没有显著影响;米糠挤压稳定化处理显著降低米糠毛油磷脂、水分及挥发物含量,随着米糠贮藏时间的延长,米糠挤压稳定化处理与未稳定化处理制备米糠毛油磷脂含量相差幅度增大;此外,米糠挤压稳定化处理可显著提高米糠毛油谷维素含量。

Effect of extrusion stabilization of rice bran with different storage time on crude rice bran oil quality

Rice bran with different storage time was used as raw material to study effects of rice bran extrusion stabilization on crude rice bran oil qualities. The results showed that compared with crude rice bran oil prepared by unstabilized rice bran, extrusion stabilization of rice bran increased acid value and peroxide value of crude rice bran oil. As storage time of rice bran increased, the difference in acid values and peroxide values of crude rice bran oils prepared by stabilized and unstabilized rice brans increased. Extrusion stabilization of rice bran had a little effect on the fatty acid composition of crude rice bran oil, only the contents of linolenic acid significantly decreased, and rice bran extrusion stabilization had insignificant effect on iodine value and saponification value of crude rice bran oil. Extrusion stabilization of rice bran resulted in a significant decrease of phospholipids, water and volatile matter content of crude rice bran oil. As storage time of rice bran increased, the difference in phospholipids contents of crude rice bran oils prepared by stabilized and unstabilized rice brans steadily increased. In addition, rice bran extrusion stabilization could significantly increase the content of oryzanol in crude rice bran oil.