Recent Advances in Listeria Mitigation for Queso Fresco

Hispanic-style fresh cheeses (HSFC), in particular queso fresco, continue to be among the most frequent cause of listeriosis outbreaks in the United States. These cheeses typically have a near neutral pH, high moisture and low salt content resulting in a food product that provides favorable conditions for the growth of spoilage and pathogenic bacteria. Refrigeration is the primary means of postpasteurization microbial control with these products. However, Listeria monocytogenes is a psychrotroph that can contaminate HSFC postpasteurization and grow during refrigerated storage. Thus, there is an urgent need for novel and effective strategies to control L. monocytogenes growth in HSFC while maintaining the sensory attributes of HSFC. In this Review, we will describe recent advances in improving the safety of HSCs. In particular, we will focus on strategies that include the incorporation of preservatives, from novel sources or commercially available, that can limit L. monocytogenes growth and processing technologies that can be used on finished products.