Starch lysophospholipids contents affect storage quality of paddy rice

Abstract

Starch Lysophospholipids (LPLs) have a significant effect on rice grain quality, but how starch LPLs affect paddy rice storage quality is barely understood. The dynamic changes in storage quality indicators of a japonica rice (XS110) and its low LPLs (XS110-J1) and high LPLs (XS110-J2) mutants were investigated. The fatty acid values (FAV) of J1 were significantly higher than those of XS110 and J2 after one year of storage under 24 and 37 °C. Although FAV rose gradually during storage time, it increased relatively more at 37 °C than 24 °C. The malondialdehyde (MDA) content increased significantly in the early stage and decreased gradually during later storage. The MDA content of rice stored at 24 °C was significantly higher than that at 37 °C. The catalase (CAT) activity exhibited a decreasing trend during storage and was relatively higher at 24 °C than 37 °C. The CAT of J2 was significantly higher than those of XS110 and J1. Total lysophospholipid content was relatively stable although some individual LPLs changed significantly during storage. The fatty acid component content in the milled rice decreased during storage, and the content at 37 °C was lower than that at 24 °C. In conclusion, paddy rice with low starch LPLs content is more susceptible to deterioration during storage, suggesting that high starch LPLs can better maintain rice quality and prolong storage time during storage of paddy rice.

Keywords: Fatty acid; Rice; Starch; Starch lipid; Storage.