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Updated: Feb 15, 2026

Light-Controlled Fermentations for Microbial Chemical and Protein Production
Published on: March 22, 2022
Real-Time Monitoring of Chemical Changes in Three Kinds of Fermented Milk Products during Fermentation Using
Yi Lu1, Hiroto Ishikawa1, Yeondae Kwon1
1Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo , 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Abstract:
Fermented milk products are rising in popularity throughout the world as a result of their health benefits, including improving digestion, normalizing the function of the immune system, and aiding in weight management. This study applies an in situ quantitative nuclear magnetic resonance method to monitor chemical changes in three kinds of fermented milk products, Bulgarian yogurt, Caspian Sea yogurt, and kefir, during fermentation. As a result, the concentration changes in nine organic compounds, α/β-lactose, α/β-galactose, lactic acid, citrate, ethanol, lecithin, and creatine, were monitored in real time. This revealed three distinct metabolic processes in the three fermented milk products. Moreover, pH changes were also determined by variations in the chemical shift of citric acid during the fermentation processes. These results can be applied to estimate microbial metabolism in various flora and help guide the fermentation and storage of various fermented milk products to improve their quality, which may directly influence human health.
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