Investigation of the Effect of Different Goji Berry (Lycium barbarum) Concentrations Added to Ground Rabbit Patties on the Survival of Listeria monocytogenes

Food safety is a critical public health priority, particularly for short shelf-life products of animal origin, such as meat. These are prone to microbial growth and physico-chemical degradation. Meat, and specifically rabbit meat, is highly nutritious but characterized by limited storage stability, representing a significant challenge for the industry. In this thesis, rabbit meat was selected as the experimental matrix within the framework of an approved research project (PRIN 2022, Project title: Goji Berry for Rabbits: Feed, Food and Animal Welfare Benefits – GORABBIT, No. 2022YK8EM9). Natural compounds, such as goji berries (Lycium barbarum), known for their antioxidant and potential antimicrobial properties, represent a promising approach to improve meat safety, quality and potentially extend shelf-life. The microbial challenge test is considered a reliable method for scientifically validating the effectiveness of such preservation strategies. This thesis employed a challenge test, following ISO 20976-2:2022, to evaluate the potential antimicrobial effect of goji berry powder (GBP) against Listeria monocytogenes in rabbit ground meat. The experimental design involved the incorporation of GBP at 3% and 5% (w/w) into ground rabbit meat in order to evaluate the potential growth of Listeria monocytogenes (ATCC 19115) during refrigerated storage at 4 ± 2°C. In parallel, additional parameters were analyzed to assess shelf life and to determine whether the addition of this ingredient improves the overall quality of rabbit meat. Previous studies suggest that dietary goji supplementation may reduce lipid oxidation and increase beneficial Lactobacillus spp. populations in rabbit meat. However, studies evaluating its direct effect when added as a natural ingredient to animal origin product, particularly regarding its potential impact against pathogens and spoilage bacteria remain limited in literature. This present thesis is expected to provide quantitative data on the potential of goji berries to inhibit Listeria monocytogenes, supporting their possible use as a natural functional ingredient to improve the safety and quality of rabbit meat products.