Plant extract and essential oils added as antimicrobials to cheeses: a review

Cheese is a food that is highly susceptible to contamination by pathogenic and spoilage microorganisms, which can result in a decrease in its shelf life and cause serious risks to the consumers' health. Consumers always require healthy food, free of synthetic preservatives, inducing a search for natural alternatives to ensure safety of the products. Essential oils and plant extracts emerge as an alternative for aiding cheese preservation. Some substances have demonstrated good effects against most pathogens and cheese spoilage microorganisms. However, intrinsic and extrinsic factors may influence the actions of these compounds when incorporated into cheese, besides affecting the product characteristics. This review aims at discussing the antimicrobial efficiency of plant extracts and essential oils as well as the impact of their incorporation on lactic bacteria and the sensory characteristics of products.