Meta-analysis: microbial inactivation in milk using pulsed electric field

Pulsed electric field (PEF) is a technology that can preserve milk into dairy products with sensory quality similar to fresh milk. Adoption of PEF at industrial level is challenging due to the various variables that may influence the microbial inactivation studies. This review aimed to quantify the inactivation effect by PEF on microbial population in milk through meta-analysis. The literatures consisted of 15 studies with 384 data in the inclusion criteria which were extracted using Hedges'd method. The order of microbial resistance to PEF from the highest to lowest was bacterial spores, Gram-positive, followed by Gram-negative bacteria. The effect of pulse shape on microbial inactivation from the highest to lowest was bipolar square, monopolar square and monopolar exponentially decaying. Increasing the intensity of PEF processing parameters increased microbial inactivation. The processing parameters influencing microbial inactivation from the highest to lowest were pulse shape, inlet temperature, treatment time, pulse width, electric field, pulses number and frequency.