Recent development in low-moisture foods: Microbial safety and thermal process

Abstract

Foodborne outbreaks and recalls of pathogen-contaminated low-moisture foods (LMFs, foods with water activity at 25 °C < 0.85) have led to numerous scientific studies on bacterial persistence, as well as newly developed industrial interventions. Conducting microbial tests of LMFs, lab tests, or validation studies in pilot plans requires complete information on protocols and parameters that need to be aware of-in particular, understanding how factors influence the thermal resistance of bacterial pathogen in LMFs is critical in designing any thermal processes. This review provides detailed information on the general protocols of microbial studies of LMFs: from pertinent pathogen identification to microbial validation studies. In particular, it reviewed the detailed procedures (e.g., lawn-harvest method), analytical protocols (e.g., recovery and enumeration of pathogens in LMFs), and specialized tools that have been utilized (even widely accepted) in laboratory-based microbial studies of LMFs. It also summarized the factors that influence the microbial validation studies. This article could support the intervention of existing pasteurization processes in the LMF industry, promoting the microbial safety of LMFs.

Keywords: Microbial validation; Pasteurization; Salmonella; Surrogate; Water activity.