Quantitative Analysis on 2‐Acetyl‐1‐pyrroline of an Aromatic Rice by Stable Isotope Dilution Method and Model Studies on its Formation during Cooking

A quantitative analysis of 2‐acetyl‐1‐pyrroline from aromatic rice samples using a stable isotope dilution method was developed. The compound was extracted from seedlings, roots, and husks at room temperature for 2 h, whereas milled or brown rice samples were extracted at 75 °C. The recovery of 2‐acetyl‐ 1‐pyrroline was linear from 5 to 5000 ng/g with sensitivity of less than 0.1 ng/g. 2‐Acetyl‐1‐pyrroline showed tautomerism with animide form. The results revealed that 2‐acetyl‐1‐pyrroline present in aromatic rice samples did not form during cooking or postharvest processes.