分析氧化淀粉与原淀粉理化特性的差异以及对面条水分分布和动态热力学性质的影响。通过添加H2O2并在50℃条件下水浴振荡4h制备氧化淀粉。结果表明:淀粉被氧化后颗粒表面及内部均有不同程度的损伤,并且在水溶液中容易发生黏连;氧化后淀粉晶型不变,结合脂质的能力增加,直链淀粉含量出现小幅降低,膨胀势与持水力显著降低(P<0.05),溶解度极显著增加(P<0.01)。将原淀粉、氧化淀粉分别与原面粉按照1∶4的比例混合,二者的湿面筋含量、面筋指数、干面筋含量无显著差异,添加氧化淀粉的样品峰值黏度、最低黏度和最终黏度极显著降低(P<0.01)。添加氧化淀粉的鲜湿面条中深层结合水比例减少,弱结合水比例增多,升温过程中,添加氧化淀粉面条的储能模量及损耗模量均小于原淀粉面条。
The differences in physicochemical properties between oxidized and native wheat starch were analyzed as well as the effect of addition of oxidized wheat starch on the quality of fresh noodles.The oxidized starch was prepared with H2O2by4h reaction at50℃.The results indicated that the surface and internal structure of oxidized starch was damaged.Oxidized starch granules were adhered to each other in aqueous suspension.Compared with native starch,the crystal type of oxidized starch was unchanged,the lipid-binding ability was increased,the content of amylose decreased slightly,the swelling power and water-holding capacity significantly decreased(P<0.05),and the solubility significantly increased(P<0.01).No significant differences in wet gluten content,gluten index and dry gluten content were demonstrated between mixtures of native and oxidized starch with flour at a ratio of1:4.The peak viscosity,minimum viscosity and final viscosity of flour were significantly reduced with the addition of oxidized starch(P<0.01).The proportion of strongly bound water in fresh noodles with oxidized starch was decreased,and the proportion of weakly bound water was increased.During heating,the storage modulus and loss modulus of noodles with oxidized starch were lower than those of the control sample.