Non-Thermal Processing (NTP) as Preservation Techniques for Microbial Safety in Selected Plant-Based Food Products: A Systematic Review

Abstract

Plant-based food products are appreciated globally due to rising health awareness, ethical concerns related to animal welfare, and sustainability impacts, alongside the growth of vegetarian lifestyles. Despite their benefits, these products present unique food safety challenges and are not exempt from microbiological hazards. Conventional thermal processing remains widely applied for microbial inactivation, but it is often associated with nutritional and sensory degradation. As a result, non-thermal processing (NTP) techniques have emerged as promising alternatives, offering microbial safety while preserving product quality. This systematic literature review is aimed at examining the application of NTP techniques in enhancing the microbiological safety of selected plant-based food products. A comprehensive search was conducted using Scopus and Web of Science (WoS) databases for articles published between 2014 and 2024. The study adhered to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, yielding 21 primary studies that fulfilled the inclusion criteria. From these findings, four main NTP themes were identified based on the principle mechanism of microbial inactivation: (1) hydrostatic pressure-based and hurdle, (2) oxidation-based, (3) radiation-based, and (4) cavitation-based techniques. The review highlights that the efficacy of NTP techniques varies significantly depending on the type of food matrices and processing conditions, with high hydrostatic pressure (HHP) being the most frequently reported NTP technique. Overall, the findings provide an updated reference on NTP-based preservation techniques for plant-based food products, facilitating food processors in selecting suitable individual or combined techniques to enhance microbial safety and shelf life with minimal impact on quality.