红外加热米糠稳定化研究

Infrared heating of stabilization of rice bran

研究以过氧化物酶残余活力和残余水分含量为评价指标,采用3因素3水平正交试验设计,研究了红外干燥中3个主要因素(温度60～80℃,处理时间15～25min,物料厚度20～30mm)对米糠稳定化效果的影响。结果表明:较佳处理工艺参数为:加热温度80℃,处理时间20min,物料厚度25mm。处理后的米糠过氧化物酶残余活力为3.91%,水分含量为4.24%。经过90d的贮存,红外处理后的米糠在室温下游离脂肪酸值(FFA)18.0mgKOH/g,4℃冷藏下10.1mgKOH/g,远远低于对照组(98.8mgKOH/g和56.9mgKOH/g)。说明红外处理对米糠稳定化效果非常显著,同时冷藏有助于有效抑制米糠酶的活性。强化储藏试验表明,90d后经稳定的米糠稳定性提高了5倍,充分说明红外处理能够使米糠长期稳定化。

The effect of Infrared heating on residual peroxidase activity and residual moisture content in rice bran were studied,and the technological parameters were optimized through an orthogonal test（L 9（3 4））.The results showed that the optimal condition was heating temperature 80 ℃,time 20 min and thickness 25 mm of rice bran.The residual peroxidase activity of rice bran under the optimal condition was 3.91%,and the moisture content was 4.24%.Free fatty acid（FFA） levels of 18.0 mg KOH/g of treated sample at the room temperature and at 10.1 mg KOH/g of treated sample at 4 ℃ cold storage after 90 day storge,Which were much lower than that of control group（98.8 mg KOH/g and 56.9 mg KOH/g respectively）.In conclusion,the Infrared heating can improved the stabilization of rice bran,and 4 ℃ cold storage could inhibit the activity of lipase.Strengthening storage test showed clearly that the infrared processing can make long-term stabilization of rice bran.