Enhancing the safety and shelf life of beef and plant-based burgers by combining High Hydrostatic Pressure (HHP) with nisin or a blueberry-derived product

The growing demand for sustainable and healthy dietary options has led to significant interest in plant-based meat alternatives though traditional meats, such as beef, remain dominant in the protein market. High Hydrostatic Pressure (HHP) stands out as a promising technology improving food safety and extending shelf life, while combining HHP with clean-label additives offers potential for process optimization. This study investigates the synergistic effect of HHP combined with nisin (500 IU/g) or blueberry-derived product (4 %) in beef and plant-based burgers to control L. monocytogenes and extend shelf life under slight temperature abuse. In plant-based burgers, HHP (600 MPa, 3 min) combined with additives, effectively delayed L. monocytogenes growth for 104 days during storage, outperforming HHP alone. At lower pressures (300–500 MPa), HHP combined with nisin or blueberry product significantly enhanced pathogen reduction in both matrices, achieving a synergistic effect of up to 1.4 log reduction. HHP (600 MPa), with or without the additives, also extended the storage period of non-inoculated plant-based burgers, maintaining the natural microflora below 3 log CFU/g for 83 days. The blueberry product notably influenced the physicochemical properties (e.g. pH, color) of both matrices, while HHP significantly affected the color of beef burgers. This study provides novel insights into the potential applications of HHP combined with natural antimicrobials, highlighting its effectiveness in plant-based meat alternatives and the significant role of the matrix in the synergistic effect. Future research should focus on sensory analysis and consumer acceptance to align these advancements with market demands. • HHP with nisin or blueberry synergistically reduced L. monocytogenes in both beef and plant-based burgers. • HHP extended plant-based burger shelf life, limiting spoilage for up to 83 days. • Matrix composition affected synergism; nisin was more effective in plant-based. • Blueberry product affected pH and color, while HHP altered beef burger color. • HHP with clean-label antimicrobials show promise for safer plant-based products.