Monitoring Seasonal Changes in Winery-Resident Microbiota

During the transformation of grapes to wine, wine fermentations are exposed to a large area of specialized equipment surfaces within wineries, which may serve as important reservoirs for two-way transfer of microbes between fermentations. However, the role of winery environments in shaping the microbiota of wine fermentations and vectoring wine spoilage organisms is poorly understood at the systems level. Microbial communities inhabiting all major equipment and surfaces in a pilot-scale winery were surveyed over the course of a single harvest to track the appearance of equipment microbiota before, during, and after grape harvest. Results demonstrate that under normal cleaning conditions winery surfaces harbor seasonally fluctuating populations of bacteria and fungi. Surface microbial communities were dependent on the production context at each site, shaped by technological practices, processing stage, and season. During harvest, grape- and fermentation-associated organisms populated most winery surfaces, acting as potential reservoirs for microbial transfer between fermentations. These surfaces harbored large populations of Saccharomyces cerevisiae and other yeasts prior to harvest, potentially serving as an important vector of these yeasts in wine fermentations. However, the majority of the surface communities before and after harvest comprised organisms with no known link to wine fermentations and a near-absence of spoilage-related organisms, suggesting that winery surfaces do not overtly vector wine spoilage microbes under normal operating conditions.

在葡萄酿制为葡萄酒的过程中，葡萄酒发酵环节会接触到酿酒厂内大量专用设备表面，这些表面可成为发酵过程间微生物双向传递的重要微生物储库。然而，在系统层面上，酿酒厂环境在塑造葡萄酒发酵微生物群（microbiota）以及介导葡萄酒腐败微生物传播方面的作用，目前尚未得到充分阐明。本研究针对一座中试规模酿酒厂内所有主要设备与表面的微生物群落，在单个葡萄采收季内开展调查，以追踪葡萄采收前、采收期间及采收后设备微生物群的动态变化。研究结果表明，在常规清洁条件下，酿酒厂设备表面栖息着随季节波动的细菌与真菌种群。设备表面的微生物群落因各生产位点的生产场景而异，受工艺操作、加工阶段及季节共同塑造。采收季期间，与葡萄及发酵相关的微生物定植于酿酒厂多数设备表面，成为发酵过程间微生物传递的潜在储库。在采收前，这些表面已栖息有大量酿酒酵母（Saccharomyces cerevisiae）与其他酵母菌，可作为葡萄酒发酵过程中这类酵母菌的重要传播媒介。然而，在采收前后的多数表面群落中，绝大多数微生物与葡萄酒发酵无已知关联，且几乎不存在腐败相关微生物，这表明在常规运行条件下，酿酒厂设备表面并不会明显介导葡萄酒腐败微生物的传播。