Abstract
Real-time monitoring of beer fermentation improves process control by allowing early detection of sluggish fermentation, abnormal yeast activity, and incomplete attenuation. This study evaluates density and pH profiles as practical indicators for real-time fermentation monitoring. Controlled beer fermentations were monitored continuously using inline density measurement and periodic pH analysis under fixed wort composition, yeast strain, pitching rate, oxygenation, and temperature conditions. Density decline, pH reduction, sugar consumption, ethanol production, yeast growth, attenuation, carbon dioxide evolution, and fermentation time were compared. The results show that density change provided a direct indicator of sugar conversion and ethanol formation, while pH decline reflected early yeast metabolic activity and acidification behavior. Abnormal fermentation batches showed delayed density reduction and unstable pH profiles. Combining density and pH improved interpretation compared with either parameter alone. The study demonstrates that simple real-time analytical profiles can support faster production decisions and more consistent fermentation management.