Abstract
Small-scale craft breweries face microbial quality risks because manual handling, flexible production schedules, yeast reuse, and compact equipment layouts can increase contamination opportunities. This study examines microbial quality control in small-scale craft brewery operations. Samples were collected from wort transfer lines, fermentation vessels, yeast storage containers, packaging equipment, and finished beer batches. Total viable count, lactic acid bacteria, wild yeast detection, pH drift, turbidity, sensory spoilage indicators, and batch stability were assessed using routine microbiological and process-control methods. The results show that contamination risk was highest during post-boil transfer, yeast handling, and packaging, where oxygen exposure and surface contact were frequent. Regular cleaning validation, rapid microbial screening, controlled yeast storage, and hygienic transfer protocols reduced batch-to-batch variation. The study demonstrates that microbial quality control in craft breweries should rely on preventive monitoring rather than only final-product testing. This approach improves product safety, flavour stability, and operational reliability.