The potential of pulsed magnetic field to achieve microbial inactivation and enzymatic stability in foods: A concise critical review

Abstract

Pulsed magnetic field (PMF) is an emerging nonthermal technique being explored in recent times for its ability to ensure adequate microbial and enzymatic inactivation in food products. The major process parameters in PMF pasteurization or sterilization of food matrices are the magnetic field intensity and the number of pulses. Biosystems such as microbes and enzymes contain several charged particles which undergo drifting under the influence of Lorentz force in the magnetic field. This leads to the formation of induced currents, leading to the inactivation of microbes and enzymes. Magnetoporation induced by PMF leads to a loss of cytosol and nucleic acid content; along with an increase in intracellular Ca2+ content, leading to microbial death. The loss of enzyme activity after PMF treatment can be majorly attributed to the unfolding of the tertiary structure. The inactivation trends reported in literature indicated towards the presence of “window effect” which comprised of two effects, namely the “intensity window” and “time window” to which the biosystem, (the microbe or the enzyme) specifically responded to. The coupling of hurdle technologies with PMF can be an attractive strategy to ensure the same. The review aims to critically review the potential of PMF as a sustainable nonthermal treatment in ensuring microbial safety and enzymatic stability in food products, prompting more research in this area.