Meta-analysis: Microbial inactivation in milk using high-pressure processing (HPP)

Abstract

High-pressure processing (HPP) is a method of food preservation where food is processed under extremely high pressure, leading to the inhibition of bacteria and enzymes and ensuring that food is safe for consumption. This meta-analysis aims to assess the inactivation effects of HPP on the microbial counts in milk. Analyses were performed using a comprehensive dataset containing 26 studies selected using specific criteria. Data were analysed using a random-effects model and results are presented as raw mean differences (RMD) with 95% confidence intervals (95% CI). Results showed that spore-forming bacteria had the highest resistance to HPP, followed by Gram-positive and then Gram-negative bacteria. A temperature range of 25–55 °C for vegetative cells and 55–90 °C for spores, a pressure of 400–600 MPa, and increasing the treatment time further enhance the efficiency of microbial inactivation. The results showed that HPP has a significant impact on inactivation of microbial counts in milk.