Preliminary optimization and quality assessment of high-pressure processing for venison preservation

The treatment conditions of a High-Pressure Processing (HPP) method were optimized for wild deer meat, considering both microbial reduction load and the impact on physicochemical and sensory characteristics. Different pressure levels (350, 450 and 550 MPa) and treatment times (3 and 6 min) were evaluated. Microbial reduction increased with higher pressure levels, however, undesirable effects on colour and sensory characteristics were also observed. The most suitable treatment was 350 MPa for 6 min, achieving a 99.9% reduction in mesophilic aerobic bacteria, Enterobacteriaceae, E. coli, and Staphylococcus spp., as well as the complete elimination of Salmonella spp. and Listeria spp. in the analysed wild deer loins. This treatment caused slight increases in L*, b* and water-holding capability, while pH and moisture content remained unaffected. Significant sensory differences were observed among raw samples, mainly related to texture and colour; however, these differences were not evident after cooking. Cryo-SEM analysis revealed structural modifications in the muscle microstructure induced by HPP, which are likely associated with the observed changes in texture. The preliminary results are promising and provide a solid basis for future studies involving a larger number of samples.