Abstract Preharvest sprouting (PHS) is one of the most serious defects that impacts rice production and grain quality. Knowledge about the effects of PHS on the eating and cooking quality (ECQ) of milled rice is limited. Here, we selected four japonica rice varieties to study the influences of PHS on grain quality. The results showed that PHS strongly led to poor grain appearance and the development of small starch granules whose surfaces were eroded. Analysis of starch fine structure revealed that PHS resulted in amylose (AM) degradation; in particular, PHS caused a decrease in the content of long AM chains. Moreover, PHS led to a decrease in the content of short amylopectin (AP) chains in the varieties Yandao 815 (YD815), Wuyugeng 27 (WY27) and Yangeng 13 (YG13), while the variety Sidao 785 (SD785) displayed the opposite trend. We propose that the main reasons for the decrease in starch crystallinity and the pasting profiles of the germinated rice were due to both the tendency of the AM content to decrease and the degree of this decrease in the content of the different AM chains along with changes in AP and other major components. All these changes caused by PHS led to a decrease in both ECQ and palatability of milled rice.

中文翻译：

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粳稻收获前发芽后籽粒品质及淀粉精细结构特征

摘要 收获前发芽（PHS）是影响水稻产量和籽粒品质的最严重缺陷之一。关于小灵通对精米的食用和烹饪质量 (ECQ) 的影响的知识有限。在这里，我们选择了四个粳稻品种来研究小灵通对谷物品质的影响。结果表明，PHS 强烈导致颗粒外观不良和表面被侵蚀的小淀粉颗粒的形成。淀粉精细结构分析表明，PHS导致直链淀粉（AM）降解；特别是，PHS 导致长 AM 链的含量减少。此外，PHS导致雁岛815（YD815）、乌玉耕27号（WY27）和雁更13号（YG13）品种短支链淀粉（AP）链含量下降，而四岛785（SD785）品种则呈相反趋势. 我们提出，发芽米淀粉结晶度和糊化曲线下降的主要原因是 AM 含量下降的趋势和不同 AM 链含量的下降程度以及AP等主要组件。所有这些由 PHS 引起的变化导致精米的 ECQ 和适口性下降。