不同类型水稻支链淀粉理化特性及其与米粉糊化特征的关系  

The Physiochemical Characteristics of Amylopectin and Their Relationships to Pasting Properties of Rice Flour in Different Varieties

作　　者：蔡一霞[1] 王维[2] 朱智伟[3] 张祖建[1] 杨建昌[1] 朱庆森[1] 

机构地区：[1]扬州大学江苏省作物遗传生理重点实验室,扬州225009 [2]华南农业大学农学院,广州510642 [3]中国水稻研究所,杭州310006

出　　处：《中国农业科学》2006年第6期1122-1129,共8页Scientia Agricultura Sinica

基　　金：广东省自然科学基金博士科研启动基金(5300357);华南农业大学博士启动基金(2005K123);江苏省作物栽培生理重点实验室开放课题(K04010);农业部财政部跨越计划(1999-3)

摘　　要：目的探索稻米中支链淀粉理化特性及其与米粉的糊化特征的关系。方法以不同类型水稻代表性品种为材料,测定支链淀粉的蓝值和最大吸收波长,用SephadexG75层析柱分析支链淀粉分枝链的链长分配,并分析其与稻米RVA谱和米饭质地间的关系。结果不同类型代表品种的支链淀粉的蓝值和最大吸收波长存在显著差异,籼型品种稻米支链淀粉的蓝值和最大吸收波长要高于粳型(巴西陆稻除外),非糯性品种支链淀粉的蓝值和最大吸收波长呈极显著的线性关系(r=0.995)。经SephadexG75分离的FrⅠ部分的链长的平均聚合度>100glucoseunite,FrⅡ部分的链长的平均聚合度为44～47glucoseunite,FrⅢ部分的链长的平均聚合度为10～17glucoseunite。不同类型代表品种支链淀粉中长分枝链与短分枝链的比率存在明显的差异,在供试的糯性品种中,籼糯含长分枝链比粳糯多;非糯性品种中,籼稻比除粳型偏籼的巴西陆稻以外的粳稻含有更多的长分枝链。在同一类型品种中,供试的籼型杂交稻的支链淀粉中含有的长分枝链要比常规稻多,陆稻品种含的长的分枝链要高于水稻品种。支链淀粉的短链部分(FrⅢ)的比率与最高粘度和崩解值呈极显著的正相关关系(r=0.969,r=0.949),而长链部分(Fr(Ⅰ+Ⅱ))与最高粘度和崩解值呈极显著负相关关系(r=-0.969,r=-0.949)。结论水稻支链淀粉的分枝链长分配与稻米品质关系密切。在非糯性品种中,硬性和凝聚性大、松弛性和粘附性小的品种,米饭的口感表现硬,咀嚼有渣感,其Fr(Ⅰ+Ⅱ)比率大,即支链淀粉所含长分枝链比率高。[Objective] The objective of this paper is to explore the relationship between the physicochemical properties of amylopectin and pasting character of rice-flour. [ Method ] Eight amylopectins from different rice varieties were used as materials, and the physicochemical properties such as blue value （BV） indicating iodine binding capacity and maximum absorption （λmax） and the chromatogram of debranched amylopection were analyzed by Sephadex G75. [Result] The results showed that the differences of BV and λmax.Ap of amylopectin among all cultivars were significant. BV and λmax.Ap of amylopectins from indica varieties were higher than that from Japonica varieties except Baxiluodao. A positive correlation （r=0.995＊＊） between BV and λmax.Ap （except waxy cultivars） was observed. The average chain length of Fr I, Fr II and Frill separated by Sephadex G75 was greater than 100 glucose unite, 44-47 glucose unite and 10-17 glucose unite, respectively. The weight percentage of chain length distribution varied with typically different cultivars. Indica waxy cultivar contained more long chains than Japonica waxy cultivar, Indica cultivar consisted of more long branched chains than Japonica cultivars except Baxiluodao, and amylopectin from hybrid combination had more long chains than that from conventional cultivar. There was a positive correlation between the proportion of short chain Frill and characters of RVA profile such as peak viscosity and breakdown （r=0.969＊＊, r=0.949＊＊）. Correspondingly, the negative correlation of the proportion of long chain Fr （ Ⅰ ＋Ⅱ ） with peak viscosity and breakdown was discovered （r=-0.969＊＊, r=-0.949＊＊）. [ Conclusion] The results suggest that the chain length distribution of debranched amylopection has a relation to rice quality. The higher ratio of Fr（ Ⅰ ＋Ⅱ ） in amylopectins from the non-waxy varieties, the more long branched chain, the texture of which shows that hardness and cohesiveness are high, and that looseness and adh

关 键 词：支链淀粉 结构 糊化特征 米饭质地 水稻 

分 类 号：S511[农业科学—作物学] TS231[轻工技术与工程—粮食、油脂及植物蛋白工程]