Differences in rice component distribution across layers and their relationship with taste

Area of Science:

• Food Science
• Agricultural Science
• Plant Biology

Background:

• Rice taste is influenced by endosperm composition, which differs across rice layers.
• Limited research exists on the relationship between rice layer composition and taste quality.

Purpose of the Study:

• To analyze the distribution and differences in rice endosperm components between varieties with excellent and poor taste.
• To elucidate the specific roles of apparent amylose content (AAC), protein content (PC), amylopectin (AP) structure, and mineral content in different rice layers (L1, L2, L3) on taste.

Main Methods:

• Comparative analysis of rice varieties with distinct taste profiles.
• Quantification of AAC, PC, AP chain lengths (Fa, Fb1+2, Fb3), and mineral content (N, Mg, Ca, K) in different rice endosperm layers.

Main Results:

• Excellent taste varieties showed lower AAC and PC, specific AP structures (less short/long-chain, more medium-chain), higher long-to-short chain ratio, and higher N, Mg, Ca in L1 compared to poor taste varieties.
• Layer 2 (L2) significantly regulated AAC and PC, improving taste in excellent varieties.
• Amylopectin structure in Layer 3 (L3) impacted taste in both variety types.
• Higher mineral content (K, Ca, Mg) in L1 correlated with improved taste across all varieties.

Conclusions:

• AAC in all layers, PC and minerals in L1/L2, and AP structure in L2/L3 are key determinants of rice taste.
• Exploiting endosperm formation processes and regulating key resources and cultivation practices are crucial for improving rice taste.