挤压膨化降解糙米中黄曲霉毒素B_1

目的:研究挤压工艺参数对黄曲霉毒素B1(aflatoxin B1,AFB1)降解率的影响,为建立粮食产品中AFB1的挤压降解技术提供依据。方法:采用双螺杆挤压机挤压膨化污染AFB1的糙米,分析挤压温度、物料水分、喂料速率和螺杆转速对糙米中AFB1降解率的影响,并通过优化工艺得到最佳工艺条件。结果:单因素试验机筒温度170℃时,AFB1降解率最高为37.1%;物料水分24%时,AFB1降解率最高为37.2%;喂料速率30 g/min时,AFB1降解率最高为37.8%;螺杆转速200 r/min时,AFB1降解率最高为39.2%;挤压降解糙米中AFB1正交试验的最佳工艺条件为机筒温度180℃、物料水分24%、喂料速率30 g/min、螺杆转速160 r/min,其降解率为48.6%。挤压过程中机筒温度极显著影响AFB1降解,物料水分显著影响AFB1降解,喂料速率和螺杆转速对AFB1降解的影响不显著。结论:挤压膨化加工能有效降解糙米中的AFB1。

Reduction of Aflatoxin B1 in Brown Rice by Extrusion Cooking

The effects of extrusion parameters on the degradation rate of aflatoxin B1 (AFB1) in cereals were explored
to provide references for processing extruded cereal products with reduced AFB1 levels. A double-screw extruder was
used to extrude AFB1-contaminated brown rice, and the degradation rate of AFB1 was investigated as a function of barrel
temperature, raw material moisture content, feeding speed and screwing speed. T he four operating parameters were
optimized by orthogonal array design. T he results of single-factor designs showed that the maximum degradation rate of
AFB1 was 37.1% at a barrel temperature of 170 ℃, 37.2% at a raw material moisture content of 24%, 37.8% at a feeding
speed of 30 g/min, and 39.2% at a screwing speed of 200 r/min. T he optimal conditions for these parameters that provided
maximum degradation rate of AFB1 (48.6%) were determined as 180 ℃, 24%, 30 g/min and 160 r/min, respectively. It was
demonstrated that barrel temperature had a highly significant effect on AFB1 degradation, raw material moisture content
exerted a significant effect, while the effects of feeding speed and screwing speed were not significant. T herefore, extrusion
offers an effective way of reducing AFB1 in cereals.