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In this study, the amylose contents in 24 commercial foxtail millet samples from major production provinces in China were determined by four different methods, namely, the improved national standard method (GB/T 15683-2008), the spectrophotometric method (NY/T 2639-2014) recommended by China’s agricultural authority, the dual-wavelength method, and the concanavalin A (Con A) method. The results of these methods were in the following decreasing order: improved GB/T 15683-2008 ≈ dual-wavelength > NY/T 2639-2014 > Con A. The correlation coefficient between the results of improved GB/T 15683-2008 and those of NY/T 2639-2014 was highest, 0.752 (P = 0), the former being about 1.41 times higher than the latter, which could allow simple prediction of the amylose content of foxtail millet. In conclusion, the improved GB/T 15683-2008 method, the dual-wavelength method and the NY/T 2639-2014 (× 1.41) method can be used to accurately determine the content of amylose in foxtail millet while greatly reducing sample testing time.

Due to the consumption characteristics of rice and the requirements of the national grain strategic reserve, rice storage is a necessary means to ensure food security. Lipids are an important nutritional component of rice and have an important impact on rice quality. The degradation of lipids during rice storage is the major reason for the deterioration of rice quality. In this article, the distribution, existing forms, structures and composition of lipids in rice, the effect of lipid degradation on the eating quality of rice, and the methods used to stabilize and detect lipids are summarized, which will provide a theoretical basis for further research and regulation of lipid degradation and quality deterioration inhibition during rice storage.

The sensory quality of cooked rice is an important factor in determining its market price, as well as consumer acceptance and breeding efforts aimed at improvement of rice grain quality. In this study, the sensory quality and physicochemical properties of three japonica rice varieties harvested in two different growing locations (Xiangshui and Hangzhou of China) were compared to determine the most important factors affecting the sensory quality. All the three varieties had higher scores for overall sensory quality in Xiangshui than in Hangzhou, indicating that the growing location is a key factor in determining the sensory quality of cooked japonica rice. In addition to growing location, variety (genotype) also had an important effect. Longdao 18 scored the highest for overall sensory quality in the two locations, whereas Longdao 30 had the lowest score in Xiangshui, and both Longdao 20 and Longdao 30 had the lowest scores in Hangzhou. Many physicochemical properties, such as apparent amylose content, protein content, thermal properties and free amino acid contents, showed significant differences between the two locations. Correlation analysis showed that apparent amylose content and protein content had contrasting effects on all the sensory attributes. The overall sensory quality was negatively correlated with protein content (r = −0.89, P

Flaxseed oil is favored by consumers because of its high nutritional value. However, the effect of thermal processing on the quality of flaxseed oil remains to be clarified. The effects of dry-air roasting on the physicochemical properties (acid value, peroxide value, color), chemical composition (conjugated diene, conjugated triene, carotenoids, tocopherol, total phenolics, Maillard reaction products, fatty acid composition), oxidation stability index, DPPH, and ABTS of flaxseed oil were investigated. The results showed that with the increase of roasting degree, the color of flaxseed oil became darker, the acid value increased, the peroxide value and conjugated diene first increased and decreased, while carotenoids, total phenols, Maillard reaction products, conjugated trienes, oxidation stability index, DPPH, and ABTS increased during roasting. The content of α-linolenic acid decreased slightly in the roasting process. Moderate roasting significantly improved the quality of flaxseed oils. The results of this study would provide support for flaxseed and flaxseed oil processing. [ABSTRACT FROM AUTHOR]

Background and Objectives: Due to the lack of comprehensive evaluation of all metabolites in rice, the metabolic reasons for taste differences are unclear. Here, two local varieties Wuyoudao 4 (WYD) (rich‐sweet flavor) and Nanjing 9108 (NJ) (delicate‐sweet flavor) were selected for ultra‐performance liquid chromatography‐tandem mass spectrometry based widely targeted metabolomic analysis. Findings: WYD and NJ were clearly separated by principal component analysis and hierarchical clustering analysis, and 231 metabolites were different between the cultivars, including 35 amino acids and derivatives, 14 saccharides and alcohols, and 12 organic acids. Among them, glucose, fructose, arabitol, and xylitol, contributed mainly to the rich‐sweet flavor of WYD rice. Leucine, phenylalanine, tryptophan, isocitric acid, and malic acid were the dominant compounds in NJ rice, and therefore, contributed primarily to the delicate‐sweet flavor. Conclusions: Vital compounds of rich‐sweet for WYD, and delicate‐sweet for NJ were clear. The differential metabolites were significantly enriched in the glucosinolate biosynthesis, valine, leucine and isoleucine degradation, and 2‐oxocarboxylic acid metabolism pathways. Significance and Novelty: This study would provide fundamental insights into the taste formation compounds and mechanism of aromatic rice. [ABSTRACT FROM AUTHOR]