Effects of Different Fruit Juices and Organic Acids on the Inactivation of Listeria monocytogenes in Kale and Celery Vegetable Juice Blends

다국어 초록 (Multilingual Abstract)

The increasing consumer demand for additive-free vegetable juices has raised concerns over food safety, particularly regarding Listeria monocytogenes in kale and celery juices. This study examined the inhibitory effects of blueberry, grape, and pineapple juices (at 12.5 and 37.5 g) and their primary organic acids on the inactivation of L. monocytogenes in kale and celery (KC) vegetable juice blends at 5, 10, and 15oC. The addition of fruit juices accelerated L. monocytogenes inactivation in vegetable juice blends. Higher concentrations of grape and pineapple juice resulted in faster inactivation, whereas increasing amounts of blueberry juice had the opposite effect, with 37.5 g of blueberry juice leading to slower L. monocytogenes inactivation. Temperature significantly influenced the inactivation rate, with L. monocytogenes exhibiting greater survival at lower temperatures. Among the organic acids tested, 0.8% malic acid alone had significant inhibitory effects. Furthermore, combinations of 0.075-0.25% malic acid with 0.5% citric or tartaric acid exhibited synergistic antimicrobial activity. These findings highlight the potential of specific fruit components and organic acids to enhance microbial safety in refrigerated vegetable juice blends. By optimizing the fruit and acid composition, this study provides valuable insights into strategies for improving the safety and sensory qualities of vegetable juice blends under various storage conditions.