微波辅助制备多孔淀粉的研究

以玉米淀粉为原料酶解制备多孔淀粉,在酶解前、后分别用微波对干淀粉进行处理,以水解率、吸油率、柠檬黄吸附量为指标,探讨了微波功率、微波时间等因素对所得产品成孔情况的影响;并对多孔淀粉颗粒的微观形态、晶体结构和糊化特性进行了分析。结果表明:(1)微波辅助处理制得多孔淀粉的水解率和吸附性较好。酶解前的高功率微波辐射30s使产品的吸油率达到最高,较之普通酶解产品提高了35%,辐射40s使产品的色素吸附量达最高,较普通产品提高了16.5%;酶解后的中功率微波辐射30s使产品的吸油率和色素吸附量较之普通酶解产品分别提高了18%和17%。(2)酶解后微波处理制得的产品成孔性优于酶解前处理,其孔径、孔深及数目较之普通酶解产品有较大改善。微波辅助制备的多孔淀粉基本保持原淀粉的结晶结构,产品结合水的能力和形成凝胶的能力均增强。

Study on Microwave-assisted Producing for Porous Starch

Porous starch was prepared with corn starch and glucoamylase, the dry starch was treated by microwave before and after enzyme hydrolysis. The effects of microwave power and time on the surface properties of porous starch were discussed. The hydrolysis ratio(HR), oil absorption ratio (OAR) and citron yellow absorbance (CYA) of porous starch were used as indexes through the experiments. Moreover, the microstructures、crystal structure and dextrin properties of the porous starch granules were compared. The results showed that (1) the product prepared by microwave treatment had better HR and absorbance ability. The optimum microwave treatment conditions before enzyme hydrolysis was at higher microwave power, 30s and 40s, HR and CYA increased by 35% and 16.5% compared to the native porous starch, respectively. The optimum microwave treatment conditions after enzyme hydrolysis was at the medium microwave power, for 30s, HR and CYA increased by 18% and 17% as compared to the native porous starch, respectively. (2) The microwave treatment after hydrolysis helped formation of more and deeper holes than the microwave treatment before hydrolysis, and the product was much better than the native porous starch, and the characteristic also excelled the native ones.