冷冻对糙米理化及加工特性的影响

Effect of freezing on physicochemical properties of brown rice

研究了-18℃冷冻0(对照)、6、12、24 h对糙米理化及加工特性的影响。结果显示,冷冻后糙米超微结构发生变化,但未产生新的基团或化学键;粗蛋白质含量显著增加,粗脂肪含量显著降低;粉体流动性变差;水合特性、阳离子交换能力、糊黏度总体呈上升趋势,胆酸钠吸附能力呈先上升后下降趋势;冷冻24 h糙米吸水性、水溶性、膨胀力、阳离子交换能力及糊黏度达到最大,冷冻6 h糙米胆酸钠吸附能力最大,冷冻处理可改善糙米的理化及加工特性。

The effects of freezing on the physic-chemical and processing characteristics of brown rice at 18℃for 0 h(control group),6 h,12 h and 24 h were studied.The results showed that the ultrastructure of brown rice changed after freezing,but no new groups or chemical bonds were generated.The crude protein content increased significantly,and the crude fat content decreased significantly;The fluidity of the powder becomes worse.The hydration characteristics,cation exchange capacity and paste viscosity increased,while the adsorption capacity of sodium cholate increased at first and then decreased.The water absorption,water solubility,swelling power,cation exchange capacity and paste viscosity of brown rice after freezing for 24 hours were maximized,and the adsorption capacity of sodium cholate for 6 hours was the highest.Freezing treatment can improve the physical,chemical and processing characteristics of brown rice.