Study on Evaluation of Different Low-Temperature Storage Period of Milled Rice(Online First, Recommended Article)

Abstract

Through the detection of quality indicators such as physicochemical, appearance, taste and gelatinization of two kinds of milled rice under three quasi-low temperature conditions of 16, 18 and 20 ℃ during storage for 6 to 12 months, the results showed that the fatty acid value, content of yellow-colored kernel and setback of rice starch all increased gradually with the increase of storage temperature and storage time, but the taste value decreased gradually, especially at 20 ℃. There were significant correlations among multiple quality indicators. After dimensionality reduction treatment by principal component analysis, 4 and 3 principal components were extracted from indica rice and japonica rice, respectively. The comprehensive scores of the principal components decreased gradually with the increase of storage temperature and time. The results of cluster analysis showed that the quality of low-moisture indica rice stored at 16 ℃ for 8 to 12 months was equivalent to that at 18 ℃ for 6 to 8 months and at 20 ℃ for 6 months. And keeping the quality of 10 to 12 months at 18 ℃, the storage period at 20 ℃ was about 8 months. The quality of high-moisture japonica rice stored at 16 ℃ for 10 to 12 months was equivalent to that at 18 and 20 ℃ for 6 months. It provides a theoretical basis for the fine control of temperature conditions in the practice of low-temperature storage of milled rice.

Keywords

• milled rice
• low-temperature storage
• comprehensive quality
• principal component analysis
• cluster analysis