蒸煮条件下马铃薯淀粉与大豆肽的相互作用及其产物结构特性的探究

Investigation of the interaction between potato starch and soybean peptide under cooking conditions and the structural properties of their products

目的探讨在蒸煮条件下马铃薯淀粉(potato starch,PS)和大豆肽(soybean peptide,SPT)复合物的相互作用及其对淀粉消化性的影响机制。方法通过在模拟热加工条件下制备成马铃薯淀粉-大豆肽复合物(potato starch-soybean peptide,PS-SPT)。采用现代分析仪器对PS-SPT的形貌特征、结构特性、功能特性和消化特性进行探究。结果SPT使淀粉起糊温度升高,峰值粘度、崩解值和回生值均降低。在模拟热加工条件下SPT的加入能促进淀粉分子重排形成局部有序聚集体,使无序化结构向有序化结构转变,从而增加了淀粉聚集体的致密性。SPT的加入会降低快消化淀粉(rapidly digestible starch,RDS)的含量,增加慢消化淀粉(slowly digestible starch,SDS)及抗性淀粉(resistant starch,RS)的含量。SPT的分子量对淀粉的形貌特征、结构特性、功能特性和消化特性影响不大。结论研究结果可以提高人们对食品多组分间相互作用的认识,为构建含SDS和RS的新型低餐后血糖生成指数(glycemic index,GI)食品的加工方法提供重要的理论指导。

Objective To study the interaction between potato starch(PS)and soybean peptide(SPT)under cooking conditions and its influence mechanism on starch digestibility.Methods The potato starch-soybean peptide complex(PS-SPT)was prepared under simulated thermal processing conditions.The morphological characteristics,structural characteristics,functional characteristics and digestive characteristics of PS-SPT were investigated by modern analytical instruments.Results SPT increased the starch gelatinization temperature and decreased the peak viscosity,disintegration value and retrogradation value.Under the simulated thermal processing conditions,the addition of SPT could promote the starch molecular rearrangement to form locally ordered aggregates,and make the disordered structure change to the ordered structure,thus increasing the compactness of starch aggregates.The addition of SPT would decrease the content of rapidly digestible starch(RDS)and increase the content of slowly digestible starch(SDS)and resistant starch(RS).The molecular weight of soybean peptide had little effect on the morphological,structural,functional and digestive properties of starch.Conclusion The research results can improve people’s understanding of the interaction between food components,and provide important theoretical guidance for constructing the processing method of new low postprandial glycemic index(GI)food containing SDS and RS.