Development of Phenolic-Rich Functional Foods by Lactic Fermentation of Grape Marc: A Review

Grape marc is a waste product produced during the winemaking process. The enormous volume of wine production worldwide creates a significant amount of grape marc each year. It is rich in nutrients and has excellent antioxidant properties. Lactic acid fermentation is a popular food preparation method, and by using grape marc as a substrate for fermentation, the pomace is preserved and the health benefits are improved, thus being a potentially valuable method that allows efficient management of pomace. This review describes the nutritional value of grape marc, the conditions necessary to ferment grape marc using lactic acid bacteria, and the characteristic chemical changes that occur during fermentation. Furthermore, it describes the research prospects for producing novel functional foods or products by interacting strains with phytochemicals in grape marc. More research is needed to optimize the use of starter cultures, improve fermentation efficiency, and develop sustainable processes.