Abstract
This study evaluated the microbiological safety of horse intestinal by-products “Qarta” before and after processing, with particular attention to changes during refrigerated storage at 4 °C. Intestinal segments were subjected to different treatments: washing only (control), immersion in citric acid solutions (0.5% and 1.0%), ultrasound treatment (35 kHz, 200 W, 5 min) and a combined treatment (1.0% citric acid followed by ultrasound). Microbiological parameters included total plate count (TPC), pH and the presence of pathogenic microorganisms (Salmonella spp., Listeria monocytogenes, Escherichia coli). The raw intestines exhibited a high initial microbial load (2.6 × 10⁵ CFU/g), confirming the inherent hygienic risks of this by-product. The combined citric acid and ultrasound treatment was the most effective, reducing TPC to 6.0 × 10² CFU/g and maintaining the lowest microbial counts during refrigerated storage for up to 9 days, while no target pathogens were detected in any treated samples. The pH values remained within the acceptable technological range (5.26–6.12), supporting product stability. Additional evaluation of chemical and radiological safety (toxic elements, pesticide residues, Cs-137, Sr-90) confirmed full compliance with TR CU 021/2011 «On Food Safety» and relevant GOST standards. Overall, the results indicate that properly processed horse intestinal by-products can meet microbiological and food safety requirements and can be considered suitable raw materials for the production of delicatessen meat productsю