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Objective: To investigate the effects of electron beam irradiation on the physicochemical properties and antioxidant activity of non-waxy and waxy proso millet. Methods: waxy (‘Yushu 1’) and non-waxy (‘Yumi 2’) proso millet were subjected to electron beam irradiation at different doses of 0 (control), 2, 4, 6, 8, and 10 kGy and were evaluated for physicochemical properties, bioactive substances and antioxidant capacity. Results: After electron beam irradiation, the color, starch content, ash content, phenolic content and antioxidant activity of non-waxy and waxy proso millet changed significantly (P 0.05). In addition, electron beam irradiation treatment significantly increased the contents of total phenols and total flavonoids, antioxidant activity and individual phenolic contents in non-waxy and waxy proso millet; the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity increased up to 78.01% and 70.22%, and the 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation scavenging capacity increased up to 61.51% and 50.57%, respectively. The contents of gallic acid, caffeic acid, resveratrol, catechin and kaempferol in proso millet extract increased, while the contents of protocatechuic acid and epicatechin remained relatively stable. The correlation analysis suggested that the total phenolic content had a significantly positive correlation with the contents of catechin and quercetin (P < 0.01), the total flavonoid content had a significantly positive correlation with the contents of rutin and gallic acid (P < 0.01), and the antioxidant activity was positively correlated with the catechin content. Compared with the control, proso millet treated with electron beam irradiation exhibited stronger antioxidant properties and higher phenolic contents, which would be worthy of further research and development.

The aim of this study was to evaluate the effects of lactic acid fermentation using three Lactobacillus strains (Lactiplantibacillus plantarum 90, Lactobacillus helveticus 76, and Lacticaseibacillus casei 37) in monoculture and binary mixture on phenolics profile, antioxidant activity and flavor volatiles in pear juice. Results showed that the colony counts of binary mixture were higher than monoculture in fermented pear juice. The total content of phenols was increased, while that of flavonoids was decreased significantly during fermentation (p < 0.05). Antioxidant activities in fermented peer juice including DPPH and ABTS radical scavenging abilities and ferric reducing antioxidant power (FRAP) were significantly improved (p < 0.05). Binary mixture of Lactiplantibacillus plantarum 90 and Lacticaseibacillus casei 37 fermentation exhibited strong DPPH radical scavenging ability, due to the increase in vanillic acid and arbutin contents. Furthermore, lactic acid fermentation improved the formation of alcohols, esters, acids and terpenoids, and reduced the contents of aldehydes and ketones. Thirty new compounds including 15 alcohols, seven esters, five acids, and three terpenoids were observed in fermented pear juice. Hierarchical cluster revealed that flavor volatiles in pear juice were improved dramatically by Lactobacillus strains fermentation, and there were dramatic differences between monoculture and binary mixture. [ABSTRACT FROM AUTHOR]

We have developed a miniaturized multi-channel parallel optical air data system with high signal-to-noise ratio for airborne application. In the system, we designed a fiber amplifier with multi-channel high-energy output that was respectively used as the transmitting signals and a compact multi-axis transceiver with an entrance pupil diameter of 70 mm that was used to receive multi-channel signals simultaneously. We demonstrated the performance of our system both on ground and on board. On ground, the measured line-of-sight speed had an average error of 0.02 m/s and a standard deviation of 0.15 m/s. On board, the standard deviation between the true air speed, angle of attack, and angle of sideslip measured by our system and a commercial Swiss air data system was 1 kt, 0.68°, and 0.54°, respectively, and those standard deviation between our system and a system with the same design but employing multiple single-axis telescopes with entrance pupil diameter of 30 mm was 0.34 kt, 0.36°, and 0.28°, respectively. The signal-to-noise ratio of our system was 4.5 times higher than that of the system with small single-axis telescopes. Our system is very promising for airborne applications because of its small volume, high signal-to-noise ratio, and high data rate.