Direct characterization of hydrolytic activities of spoiling bacteria in food
Résumé
The reduction of food spoilage is of key importance to help save food resources among the current worldwide food production. Industrial pasteurized liquid food products are particularly susceptible to microbial spoilage due to their low cooking temperatures. Several heat-resistant bacteria are involved in this phenomenon due to their enzymatic activities, expressed even at low temperatures. So far, the risk of spoilage has mainly been assessed by isolating and/or enumerating specific bacteria by classical microbiological methods, or by searching specific enzymatic activities in foods that do not require chilled storage. In order to consider more accurately the food spoilage issue in pasteurized liquid foods, this work proposes to characterize the kinetics of bacterial growth and hydrolytic activities in the food product itself at both optimal and low temperatures. This work contributes to the search for new methodologies that could help food manufacturers better assess the microbiological quality of their products for their orientation towards specific applications, contributing to the reduction of food losses.