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Toxin-antitoxin (TA) systems are widely distributed in bacterial genomes and are involved in the adaptive response of microorganisms to stress conditions. Few studies have addressed TA systems in <i>Lactobacillus</i> and their role in the adaptation to food environments and processes. In this work, for six strains belonging to <i>L. casei</i> group isolated from dairy products, the expression of DinJ-YafQ TA system was investigated after exposure to various food-related stresses (nutrient starvation, low pH, high salt concentration, oxidative stress, and high temperature), as well as to the presence of antibiotics. In particular, culturability and DinJ-YafQ expression were evaluated for all strains and conditions by plate counts and RT qPCR. Among all the food-related stress conditions, only thermal stress was capable to significantly affect culturability. Furthermore, exposure to ampicillin significantly decreased the culturability of two <i>L. rhamnosus</i> strains. The regulation of DinJ-YafQ TA system resulted strain-specific; however, high temperature was the most significant stress condition able to modulate DinJ-YafQ expression. The increasing knowledge about TA systems activity and regulation might offer new perspectives to understand the mechanisms that <i>L. casei</i> group strains exploit to adapt to different niches or production processes.