[关键词]
[摘要]
以普通南方大米淀粉为原料,采用α-淀粉酶和糖苷酶协同制备多孔大米淀粉,研究了酶含量、酶配比和时间等因素对多孔淀粉水解率和吸油率的影响,得出制备多孔大米淀粉的最佳条件为:酶含量1.0%(以淀粉干基计),酶配比(α-淀粉酶:葡萄糖苷酶)1:12,处理时间12 h,所得多孔淀粉的水解率为50%,吸油率为96.3%。在此基础上,分别选择原淀粉和多孔大米淀粉(水解率分别为30%、40%和50%)与0.1 mol/L的乙酸锌水溶液进行脉冲电场处理协同强化锌络合,脉冲电场处理条件为电压20 V、频率1 kHz、流速24 mL/min,有效处理时间分别为2.88×103 μs、8.64×103 μs和14.4×103 μs;借助扫描电子显微镜(SEM)及红外光谱(FT-IR)对淀粉络合物的显微结构进行研究,并通过原子吸收测定淀粉络合锌的含量,最终得出:水解率40%的多孔大米淀粉经脉冲电场(2.88×103 μs)处理后的锌络合含量最高,为352.85 mg/100 g。
[Key word]
[Abstract]
The effects of enzyme content, enzyme ratio and time on hydrolysis rate and oil-absorption rate of porous rice starch, which was prepraed byα-amylase and glucosidase, were studied by using the common southern rice starch from China as raw materials The optimized conditions for preparation of porous rice starch were as follows: enzyme content,1.0%, enzyme ratio, 1:12, processing time, 12 h, and the hydrolysis rate and oil-absorption rate of porous starch were 50% and 96.3%. Under this condition,, the original starch and porous rice starch (hydrolysis rate of 30%, 40% and 50%) were selected for strengthing thereaction of Zn complex by PEF treament with zinc-acetate solution (0.1 mol/L), and the conditions were as follows: voltage, 20 V, frequency, 1 kHz, fluid rate, 24 mL/min, treatment durations, 2.88×103 μs, 8.64×103 μs and 14.4×103 μs. In addition, the microstructure of the starch complex was investigated by scanning electron microscope (SEM) and infrared spectroscopy (FT-IR), and the zinc content of starch-Zn complex was determined by atom absorption spectroscopy. Consequently, the highest zinc contentwas 352.85 mg / 100 g with the hydrolysis-rate of 40% and PEF treatment time of 2.88×103 μs.
[中图分类号]
[基金项目]
广州市科技计划项目(201610010104);国家自然科学基金资助项目(31301559、21376094);广东省科技计划项目(2017B020207002)