Graduate Student Literature Review: Network of flavor compounds formation and influence factors in yogurt

Yogurt is popular as a natural and healthy food, but its flavor greatly affects acceptability by consumers. Flavor compounds of yogurt are generally produced by the metabolism of lactose, protein, and fat, and the resulting flavors include carbonyls, acids, esters, alcohols, and so on. Each flavor compound can individually provide the corresponding flavor, or it can be combined with other compounds to form a new flavor. The flavor network is formed among the metabolites of milk components, and acetaldehyde, as the central compound, plays a role in connecting the whole network. The flavor compounds can be affected by many factors, such as the use of different raw milks, ways of homogenization, sterilization, fermentation, postripening, storage condition, and packaging materials, which can affect the overall flavor of yogurt. This paper provides an overview of the volatile flavor compounds in yogurt, the pathways of production of the main flavor compounds during yogurt fermentation, and the factors that influence the flavor of yogurt, including type of raw milk, processing, and storage. It also aims to provide theoretical guidance for the product of yogurt in ideal flavor, but further research is needed to provide a more comprehensive description of the flavor system of yogurt.