Metabolism of Lactococcus cremoris under non-growing and cheese production conditions

Summary

Cheese is an important food commodity. The historical knowledge of cheesemaking is abundant, but the biological understanding of cheese ripening remains largely undiscovered. During ripening, flavors slowly develop as a result of starter bacteria activities and spontaneous chemical reactions. In the past, starter bacteria was thought to die during cheese ripening and the released enzymes were considered as the main agent of flavor development. Consequently, starter bacteria was mostly optimized for rapid acidification during cheesemaking. In the last two decades, this notion has slowly been challenged. Starter bacteria were shown to remain non-growing but metabolically-active throughout years of cheese ripening and to directly contribute to flavor development. Here, we investigated the effect of various growing conditions of starter bacteria and cheesemaking conditions on the cellular physiology and flavor development by non-growing cells. The study is relevant for fermented food productions, particularly where non-growing cells during ripening or storage influence product quality.