The textural properties of cooked convenience rice upon repeated freeze–thaw treatments are largely affected by water mobility at grain level
The textural properties of cooked convenience rice upon repeated freeze–thaw treatments are largely affected by water mobility at grain level
复制标题
反复冻融处理后熟方便米的质构特性在很大程度上受到颗粒水平水分流动性的影响
DOI：
10.1016/j.foodres.2022.112254
复制
发表时间：
2023
影响因子：
8.1
通讯作者：
Sun Baoguo
中科院分区：
文献类型：
--
作者：
Lu Shiyi;Li Jie;Xu Minghao;Mu Yifan;Wen Yangyang;Li Hongyan;Wang Jing;Sun Baoguo
糙米 (BR) 是一种很有前景的方便米来源，大部分都是冷冻储存的。然而，冷冻和解冻可能会导致大米质地品质恶化。为了研究冻融循环对大米质地的影响，将 BR、麸层部分破裂的预处理 BR（UER）和白米（WR）进行烹煮并进行反复冻融循环处理，测量它们的质地特性、水分分布和淀粉结构的变化。结果表明，反复冻融处理导致所有煮熟的米饭的硬度和粘性逐渐降低。大米硬度的降低可以通过扫描电子显微镜下大米内部淀粉孔径的增大来解释。 WR 中的水分迁移对多次冻融循环的响应最快，其次是 UER，而 BR 中的水分迁移最慢。此外，在反复冻融循环后，WR、BR和UER导致支链淀粉回生和链长度分布的程度相似。它表明淀粉变化对确定不同大米样品抗冻融的质地的影响相似且较小。水流动性往往是导致完全糊化大米样品质地差异的主要因素。本研究重点关注水分分布与淀粉回生之间的关系，以更好地了解多次冻融对保持不同表层程度的米饭质地品质的影响。
Brown rice (BR) is a promising source for convenience rice that are mostly stored frozen. However, freezing and thawing may cause deterioration in rice texture quality. To investigate how rice texture is influenced by freeze–thaw cycles, BR, the pretreated BR with partially ruptured bran layer (UER) and white rice (WR) were cooked and treated with repeated freeze–thaw cycles, with their textural properties, variations in moisture distribution and starch structure being measured. Results showed that the repeated freeze–thaw treatment induced a progressive reduction in hardness and stickiness of all cooked rice. The reduced hardness of rice could be explained by the enlarged pore size of starch inside rice under scanning electron microscopy. Moisture migration in WR was the fastest responding to multiply freeze–thaw cycles, followed by UER, while water mobility in BR was slowest. Moreover, WR, BR and UER resulted in a similar extent of amylopectin retrogradation and chains length distribution after repeated freeze–thaw cycles. It indicated similar and minor effect of starch variations on determining the texture of different rice samples against freeze-thawing. Water mobility tended to be a main factor leading to the textural difference of fully gelatinized rice samples. This study focused on the relationship between water distribution and starch retrogradation, providing a better understanding on influences of multiple freeze-thawing on textural quality of cooked rice maintaining different extents of surface layer.