Gochujang is a Korean fermented hot pepper paste beneficial to human health by providing various nutrients. In this study, its physicochemical characteristics were identified, and its microbial communities were analyzed by high-throughput sequencing. The interrelationship between physicochemical characteristics and microbial composition was investigated to reveal the properties of gochujang before and after fermentation. After fermentation, all samples showed decreased salt concentration, pH, and reducing sugar content, while the acidity and amino-type nitrogen increased. The water content, salt concentration, amino-type nitrogen, and reducing sugar differed according to the batches of samples. Bacillus, Aerosakkonema, and Enterococcus were identified as the predominant bacterial genera. Furthermore, Aerosakkonema was the most abundant genus before fermentation; however, it was replaced by Bacillus as it decreased after fermentation. For the fungi, Aspergillus dominated before fermentation, whereas Zygosaccharomyces and Millerozyma dominated after fermentation. The high level of amino-type nitrogen in gochujang was related to the relative abundance of B. haynesii/B. licheniformis before fermentation. Additionally, the high abundance of Z. rouxii after fermentation was related to the flavor of gochujang. This comprehensive analysis of the microbial community associated with the physicochemical properties of gochujang could help in understanding the factors affecting the quality of the product.

Based on the superimposition of four-dimensional response surfaces with respect to TPC, EDA, NSA and SDA, the optimum ranges of extraction conditions were 70-150 W MWP, 30-50% ETC and 8-18 min EXT.

The puffing process could provide an alternative mean to produce functional ginseng products, along with a reduction in processing time as compared to traditional red ginseng processing by steam.

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The effects of different nuruk contents and fermentation methods (AV, vinegar fermented in an agitated culture; SV, vinegar fermented in a static culture) on organic acids and volatile compounds in brown rice vinegars were investigated. In the SV, the contents of acetic, oxalic, tartaric, and malic acids increased with hipher contents of nuruk. Acetic, tartaric, and malic acid contents were higher in the SV than those in the AV. Volatile compounds that can affect vinegar quality, including acetic acid, isoamyl acetate, phenethyl acetate, and phenethyl alcohol were present at high concentrations in the AV. With the increase in nuruk contents in the AV, acetic acid content decreased and isoamyl acetate and phenethyl acetate content increased. No significant differences in sensory scores were observed regarding the amount of nuruk and the type of fermentation. However, electronic-nose analysis showed its potential to effectively differentiate different samples.