Cloth-Based Sampling: Principles, Applications, and Future Opportunities for Non-Destructive Microbiological Testing of Foods

Representative sampling for microbiological testing is limited because contamination is rare and heterogeneously distributed. Conventional excision and grab methods consume product, cover limited surface area, and require substantial labor. Rinse samples, such as those used for poultry carcasses and parts, are difficult to aggregate across a lot. Cloth-based sampling uses a sterile porous polymeric material to transfer microorganisms from food or environmental surfaces into a sample suitable for culture, enrichment, enumeration, or molecular analysis. This review describes the physical and statistical principles of cloth sampling, distinguishes localized collection from aggregated sampling, and examines applications in beef, poultry, fresh produce, and environmental monitoring. Beef studies and U.S. regulatory implementation provide the strongest evidence base, demonstrating the efficacy of cloth-based sampling for the validated raw-beef-trim application. Poultry comparisons support cloth sampling as a nondestructive alternative to rinse collection under specified conditions. Recent commercial produce work indicates that time-integrated cloth collection can match or exceed grab-sample detection frequencies for selected microbial index targets, while penetrative formats may improve access to difficult-to-sample leafy-green surfaces. Performance depends on cloth material, moisture, contact mechanics, product geometry, target location, transport, and laboratory recovery. Cloth sampling should therefore be validated as a complete sampling system rather than assumed to be universally equivalent across matrices. Future work should quantify transfer and release kinetics, effective sampled surface or mass, uncertainty, lot boundaries, and compatibility with quantitative and culture-independent analyses.