淀粉和变性淀粉糊化特性的研究

STUDIES ON GELATINIZING CHARACTERISTICS OF NATIVE AND MODIFIED STARCHES

用布拉班德淀粉粘度仪研究了不同的原淀粉和变性淀粉的糊化特性,用成糊温度(PT),热糊粘度(H)、冷糊粘度(C)、和各种粘度差,即破损值或崩解值(P-H)、回值(C-P)、总回值或稠度(C-H)、相对破损值(P-H/C-H)等来表示.这些特性在不同淀粉之间存在明显的差异.淀粉中直链淀粉的含量对淀粉的糊化和老化倾向影响很大.变性处理可以改变原淀粉的糊化特性,例如酯化(或醚化)能使玉米淀粉的成糊温度降低,老化倾向减小,粘度稳定性变差,而交联则使其粘度稳定性增强,能够抵抗酸和剪切力的影响.

The gelatinizing characteristics in terms of pasting temperature ( PT ), peak viscosity ( P ), hot paste viscosity ( H ), cold paste viscosity (C) and the various viscosity differences i.e.breakdown ( P-H ) , set back ( C-P), total setback or consistency(C-H) and relative breakdown (P-H/C-H) of the starches from different sources and modified starches were studied with Brabender Visco/Amylo/Graph ) .Significant differences in these characteristics of various starches had been found.The amylose content present in starch significantly affected its gelatinization and tendency for retrogradation.The gelatinizing characteristics of native starch could be changed by means of modifying treatment.For example, the pasting temperature and retrogradation tendency of corn starch and viscosity stability were decreased by esterification or etherification.However, the viscosity stability in ronsistance to acid and shearing were increased by crosslinking.