Abstract
This study investigated the combined effects of ultrasound (US) and citric acid (CA) treatments on the microbiological safety and mechanical integrity of natural horse casings during storage.Derived from horse intestines, these casings are susceptible to microbial contamination that can impact food safety and quality.Samples underwent treatment with ultrasound (35 kHz, 200 W for 5 or 10 min), citric acid at a concentration of 0.5% and 1%, and their combination.Results showed that the treatment combination of 1% CA with US for 5 min yielded the lowest initial total plate count (TPC) at 1.63 log cfu/g and maintained effective microbial control, with TPC at 3.24 log cfu/g by day 13 of storage at 4°C.This combination also preserved the mechanical properties of the casings, achieving tensile strength of 5.7 MPa and elongation at break at 58%.The findings suggest that combining US and CA significantly enhances the microbial safety and mechanical resilience of horse casings, offering a promising approach for the meat processing industry.