The microbiota of the pretreatment phase is crucial to the assembly of the microbial community in the saccharification of fuyu-flavor baijiu. This study investigates the shifts in microbial community diversity from the pretreatment of raw materials to the end of saccharification. High-throughput sequencing reveals that Lactobacillus, Weissella, and Bacillus in the bacterial community and Rhizopus, Candida, Pichia, and Aspergillus in the fungal community are predominant during raw material pretreatment and saccharification processes. Also, 11 bacterial genera, including Bacillus, Lactobacillus, Leuconostoc, Weissella, Lactococcus, and Acetobacter, and eight yeast genera, including Candida, Pichia, Saccharomyces, and Wickerhamomyces, were isolated from the initial saccharification stage by culture-dependent approaches. Sourcetracker analysis indicates that the cooling grains and rice husks were the main contributors to the bacterial community composition of the saccharification process, and Qu was the main contributor to the shaping of the fungal community structure during the saccharification process. Abundance variation of the predictive functional profiles of microbial communities encoding for key enzymes involved in pyruvate metabolism, starch and sucrose metabolism, and glycolysis/gluconeogenesis during the pretreatment and saccharification phases were inferred by PICRUSt2 analysis. The results of this study will be utilized to produce consistently high-quality fuyu-flavor baijiu via better controlling the shaping of microbial community structures during the pretreatment and fermentation processes.

The microbial terroir is an indispensable part of the terroir panorama, and can improve wine quality with special characteristics. In this study, eight autochthonous yeasts (Saccharomyces cerevisiae), selected in Huailai country, China, were trailed in small-scale and pilot fermentations for both white (Riesling and Sémillon) and red (Cabernet Sauvignon and Syrah) wines and evaluated by GC-MS analysis and the rate-all-that-apply (RATA) method. Compared to commercial yeast strains, the indigenous yeasts were able to produce higher concentrations of ethyl esters and fatty acid ethyl esters, and higher alcohol, resulting in higher odor activity values of fruity, floral attributes. Marked varietal effects were observed in the pilot fermentation, but yeast strains exerted a noticeable impact in modulating wine aroma and sensory profile. Overall, indigenous yeast could produce more preferred aroma compounds and sensory characteristics for both white and red wines, demonstrating the potential for improving wine quality and regional characteristics.

The rapidly expanding probiotic industry demands efficient methods for quality assessment of probiotic products. We previously established a microscopic imaging and Raman spectroscopy (miRS) based approach for rapid identification and tests for viability and vitality at single‐cell resolution via single‐cell Raman spectra (SCRS), yet its wider application is limited by the throughput of SCRS acquisition. Here, we employed a Raman flow cytometry (RFC) approach to accomplish this mission, which features a greatly simplified experimental workflow yet with >10‐fold higher throughput than miRS. At SCRS acquisition speed of one bacterial cell per second, RFC achieves much higher sampling depth, leading to higher accuracy of species classification than miRS in both reference ramanome database construction and quality assessment of probiotic products. Specifically, based on the fingerprint regions, the accuracy in classifying species and strains is notably improved, both for an isogenic population and for a multi‐strain probiotic product. Moreover, for probiotic products with highly biased compositions, the sensitivity of detecting and classifying low‐abundance members is order‐of‐magnitude higher. Furthermore, based on the fingerprint regions plus the C‐D band, D ₂ O‐probed RFC rapidly yields viable‐cell counts and quantifies single‐cell vitality in a species/strain‐resolved fashion yet without the need for fluorescence labeling, underscoring its strength over propidium monoazide (PMA)‐based fluorescence flow cytometry. Due to its speed, accuracy, sensitivity, rich information and ease of use, RFC is a powerful platform for quality assessment for probiotics and other live‐cell products.

Aspergillus cristatus is a key microorganism involved in the fermentation of Fu brick tea, but systematic strain-level safety data remain limited despite its long history of use in dark tea production. In this study, the toxicological safety of A. cristatus CCNH008 was assessed through acute oral toxicity assay, a 90-day repeated oral toxicity study with a recovery period and genotoxicity assays. In acute oral toxicity tests, CCNH008 caused no mortality, no adverse clinical signs, and no treatment-related effects on bodyweight or pathology in mice or rats, with an LD₅₀ greater than 10 g/kg bodyweight. In the 90-day repeated oral toxicity study in rats, the oral administration of CCNH008 at doses up to 1.67 g/kg bodyweight/day produced no treatment-related changes in clinical signs, bodyweight, food consumption, hematological or biochemical parameters, urinalysis, organ weights, or histopathology, including during a 28-day recovery period. Genotoxicity was evaluated using a bacterial reverse mutation assay, an in vitro mammalian chromosome aberration test, and an in vivo mammalian erythrocyte micronucleus test; no mutagenic or clastogenic effects were observed. Collectively, these findings demonstrate that CCNH008 shows no evidence of acute, subchronic oral toxicity, or genotoxicity, providing important strain-level safety evidence to support its potential application in food-related products.