The differences in metabolites, starch structure, and physicochemical properties of rice were related to the decrease...

Area of Science:

• Agricultural Science
• Food Science
• Biochemistry

Background:

• Nitrogen fertilizer is crucial for rice yield but can negatively impact cooked rice taste.
• Varietal differences in rice taste quality are observed, but underlying mechanisms require further investigation.

Purpose of the Study:

• To investigate the impact of nitrogen fertilizer levels on rice physicochemical properties and taste quality.
• To elucidate the mechanisms behind varietal differences in rice taste quality under varying nitrogen conditions.

Main Methods:

• Two rice varieties (Meixiangzhan2hao and Exiang2hao) were grown under two nitrogen fertilizer levels.
• Analysis of physicochemical properties, amino acid content, protein content, starch characteristics, and lipid metabolites.
• Evaluation of cooked rice taste quality.

Main Results:

• High nitrogen fertilizer increased amino acid and protein content, altering tryptophan metabolism.
• Elevated protein and starch short-range order inhibited starch gelatinization, reducing rice taste quality.
• Exiang2hao exhibited less protein increase, lower amylose and crystallinity, and higher lipid metabolites under high nitrogen, resulting in a less pronounced taste quality reduction.

Conclusions:

• High nitrogen fertilizer application negatively affects rice taste quality by altering its chemical composition, particularly protein and starch.
• Varietal differences, like those observed in Exiang2hao, can mitigate the negative effects of high nitrogen on rice taste.
• Findings offer insights for improving rice taste quality through strategic cultivation and breeding.