Viability of Trichinella spiralis in traditional sour pork fermentation and its inactivation by microwave heating: Implications for zoonotic risk and food safety

Vet World Vol.18 June-2025 Article - 23

Research Article

Veterinary World, 18(6): 1660-1666

https://doi.org/10.14202/vetworld.2025.1660-1666

Atchara Artchayasawat^1,2

, Benjamabhorn Pumhirunroj^2,3

, Sukhonthip Khueangchiangkhwang⁴

, Thidarut Boonmars^2,5

, Parichart Boueroy⁶

, Porntip Laummaunwai⁵

, and Panaratana Rattanasuwan⁷

1. Department of Agriculture and Resources, Faculty of Natural Resources and Agro-Industry, Kasetsart University, Chalermphakiat Sakon Nakhon Province Campus, Sakon Nakhon, 47000, Thailand.

2. Cholangiocarcinoma Research Institute, Khon Kaen University, Khon Kaen, 40002, Thailand.

3. Program in Animal Science, Faculty of Agricultural Technology, Sakon Nakhon Rajabhat University, Sakon Nakhon, 47000, Thailand.

4. Department of Parasitology and Infectious Diseases, Gifu University Graduate School of Medicine, Gifu, Japan.

5. Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.

6. Department of Community Health, Faculty of Public Health, Kasetsart University, Chalermphakiat Sakon Nakhon Province Campus, Sakon Nakhon, 47000, Thailand.

7. Department of Anesthesiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.

Background and Aim: Cultural dietary practices involving the consumption of raw or undercooked meat, such as traditional sour fermented pork, pose significant risks for foodborne parasitic infections, particularly trichinellosis caused by Trichinella spiralis. This study aimed to evaluate the viability of T. spiralis larvae during sour pork fermentation and to assess the efficacy of microwave heating as a practical method for inactivating the larvae.

Materials and Methods: Laboratory-bred hamsters were experimentally infected with T. spiralis to obtain encysted muscle larvae. Infected muscle samples were incorporated into a traditional sour pork recipe and fermented at ambient temperature (28–30°C) for 5 days. Larval viability was assessed daily using propidium iodide staining and confocal microscopy. In a separate experiment, pork slices embedded with infected muscle were subjected to microwave heating at 400 W (1–4 min) and 800 W (0.5–4.5 min). Post-treatment viability was determined similarly.

Results: Encysted larvae remained viable throughout the 5-day fermentation period, with no uptake of propidium iodide observed in any samples. In contrast, microwave heating at 400 W for 3 min or at 800 W for 1 min or longer resulted in complete larval inactivation, as evidenced by positive staining. Non-heated controls retained viable larvae, while boiling served as an effective positive control for inactivation.

Conclusion: Traditional sour pork fermentation does not inactivate T. spiralis larvae within 5 days, underscoring a persistent zoonotic risk. However, microwave heating offers a rapid and accessible intervention for larval inactivation. These findings underscore the significance of public health education and food safety protocols in regions where the consumption of raw meat is culturally prevalent.

Keywords: fermentation safety, foodborne parasitosis, larval viability, microwave heating, sour fermented pork, Trichinella spiralis, zoonotic infection.

How to cite this article: Artchayasawat A, Pumhirunroj B, Khueangchiangkhwang S, Boonmars T, Boueroy P, Laummaunwai P, and Rattanasuwan P (2025) Viability of Trichinella spiralis in traditional sour pork fermentation and its inactivation by microwave heating: Implications for zoonotic risk and food safety, Veterinary World, 18(6): 1660-1666.

Received: 07-12-2024 Accepted: 19-05-2025 Published online: 19-06-2025

Corresponding author: Thidarut Boonmars E-mail: bthida@kku.ac.th

DOI: 10.14202/vetworld.2025.1660-1666

Copyright: Artchayasawat, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.