In-Process Microbial Load Dynamics and Production Environment Microbial Hygiene in the Manufacturing of Low-Processed Vacuum-Packed RTE Pork Bar with Dried Plasma

TL;DR

This study examines how microbes spread during the production of vacuum-packed pork bars, identifying key contamination points and offering insights to improve food safety.

Contribution

The study provides empirical data on microbial dynamics in low-processed RTE meat production, highlighting step-specific contamination risks.

Findings

Microbial counts increased by 1.5–2.3 log CFU/g during early processing steps, indicating critical contamination-prone operations.

Environmental monitoring identified contamination hotspots on frequently handled surfaces, especially in pre- and post-lethality stages.

Despite effective baking, low-level microbial reappearance during packaging and maturation suggests post-process contamination risks.

Abstract

Low-processed ready-to-eat (RTE) meat products are highly vulnerable to microbial contamination, yet data on in-process dynamics remain limited. This study investigated microbial dynamics and environmental hygiene during the production of vacuum-packed RTE pork bars containing dried plasma, with a focus on identifying process-inherent contamination risks. Samples were collected at successive processing stages and from food-contact and non-food-contact surfaces. Process hygiene was assessed using indicator organisms (Aerobic Plate Count, Enterobacteriaceae, lactic acid bacteria, yeast and mold, E. coli, S. aureus counts), while food safety relevance was addressed by monitoring Listeria monocytogenes and Salmonella spp. Microbial counts increased by approximately 1.5–2.3 log CFU/g between early processing steps, indicating that these operations are critical contamination-prone steps. Environmental monitoring revealed contamination hotspots on frequently handled surfaces, highlighting the vulnerability of pre- and post-lethality stages. Despite the baking achieving a mean microbial reduction of ~3 log CFU/g, consistent with effective thermal processing, low-level microbial reappearance during packaging and maturation indicated the potential for post-process contamination. The results demonstrate that production-inherent factors largely drive microbial contamination patterns and may persist even in facilities operating under implemented GHP, GMP, and HACCP-based procedures, highlighting step-specific limitations rather than system failure. By providing empirical data on in-process microbial dynamics, this study supports both scientifically based and risk-based approaches within Food Safety Management Systems, offering transferable insights applicable to similar RTE meat production environments. The findings may assist food business operators in optimising targeted control measures and strengthening risk-based decision-making in low-processed RTE meat production.

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