Effect of high pressure processing combined with lactic acid bacteria on the microbial counts and physicochemical properties of uncooked beef patties during refrigerated storage

The effect of high pressure processing (HPP) at 300, 400, and 500 MPa combined with Lactobacillus acidophilus was assessed on uncooked ground beef patties (BP) during refrigerated storage of 10 days. BP were evaluated in terms of microbial growth, color, pH, and lipid oxidation during the storage. Untreated BP had a significantly higher total aerobic count (6.74 log CFU/g) than BP treated with HPP 500 MPa + L. acidophilus (3.35 log CFU/g) on Day 10 of storage. Yeasts and mold counts of only 0.80 log CFU/g were detected in BP treated with HPP 500 MPa + L. acidophilus on Day 10 of storage. BP treated with combined process showed significant color retention, a delayed decrease in pH value, and inhibition of lipid oxidation during storage. The HPP 500 MPa + L. acidophilus showed the highest scores for all sensory parameters. This combined process can be used as an effective treatment for maintaining the microbial stability and quality of BP during storage. Novelty impact statement High pressure processing at 500 MPa was applied as a postprocessing treatment in conjunction with lactic acid bacteria for improving the microbiological safety and enhancement of shelf-life of fresh ground beef patties during refrigerated storage for intended usage at home and fast-food restaurants.

Automated summary

The study showed that using high pressure processing at 500 MPa combined with Lactobacillus acidophilus treatment significantly reduces microbial counts, maintains color, delays pH decrease, and inhibits lipid oxidation, achieving the highest scores in all sensory parameters.