Study of the effect of milling on nutritional and sensory quality and volatile flavor compounds of cooked highland barley rice

Abstract

To determine the optimal degree of milling (DOM) for processing highland barley rice (HBR), a comprehensive assessment of the nutritional composition, polyphenol content, antioxidant capacity, edible quality, and aroma compounds was conducted in 10 cooked HBR with varying DOM. Gas chromatography-ion mobility spectroscopy (GC-IMS) and relative odor activity value (ROAV) analysis were employed to identify the key volatile flavor compounds in cooked HBR. The results demonstrated that an increase in DOM led to a decrease in protein, fat, fiber, ash, total phenol, total flavonoid contents, and antioxidant activity of the cooked HBR. Conversely, total starch and β-glucan exhibited an increasing trend. The cooked HBR achieved its optimal overall sensory quality when the milling mass loss rate reached 14.54%. Additionally, 35 aroma substances in different cooked HBR samples were identified, including alcohols, aldehydes, ketones, and esters. Out of these compounds, 14 were deemed key volatile flavor compounds with a ROAV ≥1, and 7 compounds significantly contributed to the flavor differences among the samples. A comprehensive analysis found that a DOM of 14.54% was more suitable for preserving the nutritional function and improving the flavor characteristics of cooked HBR. This study offers valuable theoretical support for the development of HBR products.