Abstract
The eating quality of rice is the sensory characteristics of rice after cooking, and rice with high eating quality is often favored by consumers. Soaking is a necessary step before the rice is cooked. During the soaking process, the water absorption of rice will greatly affect the final eating quality of cooked rice, but the key factors affecting the water absorption of rice and its process mechanism are not clear. In this study, rice with different eating qualities was used as a material to explore the morphological changes and proton distribution during rice soaking. The outer layer of low eating quality rice had a higher protein content. During the soaking process, the high protein content in the outer layer may inhibit the entry of water into the rice, resulting in a decrease in water absorption and proton mobility. The results of scanning electron microscopy showed that moisture entered the inner layer of rice from the outer layer of rice by cracks, and the cracks disappeared after the soaking was completed. Compared to the high eating quality rice, the water was inhibited in entering the low eating quality rice.
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The data analyzed during the current study are available at a reasonable request.
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Acknowledgements
This work was supported by the National Natural Science Foundation of China (No.32272204), Key Project of Hongshan Laboratory (No. 2021hszd002), Guangdong Provincial Key R And D Program (No. 2021B0202030002), the Strategic Consulting Research Project of Chinese Academy of Engineering (No. 2021-XZ-30), Fundamental Research Funds for the Central Universities (No. 2662019QD049). The authors would like to thank Dr. Zhe Hu for his help with optical microscopy. The optical microscopy data was acquired at the State Key Laboratory of Agricultural Microbiology Core Facility. The authors would like to thank Miss Jing Chen for her help in writing papers and creativity.
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217_2022_4173_MOESM1_ESM.tif
Supplementary file1 Rice protein content and eating quality. The a, b, c, and d referred to the protein content, hardness, stickiness, and taste values of the rice, respectively. Different letters denote statistical differences at the 0.05 level (TIF 265 KB)
217_2022_4173_MOESM2_ESM.docx
Supplementary file2 Pasting characteristics of rice starch. Different letters denote statistical differences at the 0.05 level (DOCX 16 KB)
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Shi, S., Zhang, G., Zhao, D. et al. Changes in water absorption and morphology of rice with different eating quality during soaking. Eur Food Res Technol 249, 759–766 (2023). https://doi.org/10.1007/s00217-022-04173-x
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DOI: https://doi.org/10.1007/s00217-022-04173-x