THE INFLUENCE OF YOGURT MARINADE IN COMBINATION WITH ESSENTIAL OILS ON THE MICROBIOLOGICAL QUALITY OF BEEF

Abstract

This study investigated the influence of yogurt marinade enriched with coriander and basil essential oils (EOs) on the microbiological quality of beef during refrigerated storage (4 ± 1 °C). Specific objectives included evaluating the effects of air exposure (vacuum-packed vs aerobic storage), marinade addition (with or without), and EOs addition (with or without) on selected culturable bacteria. The selected groups of bacteria monitored were coliform bacteria (CB), lactic acid bacteria (LAB), Pseudomonas spp., and total viability count (TVC). The quantitative abundance of selected microbial groups was evaluated by dilution plating method and the identification of microorganisms was assessed using MALDI-TOF mass spectrometry. The results demonstrated that the specific combination of yogurt marinade, vacuum packaging and EOs, significantly reduce bacterial counts and diversity in beef samples. These combinations showed significantly lower TVCs on the 20^th day of storage (p ≤ 0.05) compared to control and other treatments. The TVCs likely decreased not only due to the antimicrobial properties of the added EOs but also as a result of the beneficial LAB present in the yogurt marinade. Overall, the storage condition played a crucial role, with vacuum-packed samples exhibiting lower microbial counts compared to aerobically stored samples, regardless of the marinade or EO treatment. The Lactobacillaceae family, with Latilactobacillus sakei as a representative, was the most abundant bacterial group. L. sakei was consistently present across all samples at every time point, indicating its dominance in the microbial community of the studied beef samples. Ralstonia pickettii from the Burkholderiaceae family was the second most prevalent species. The study provides valuable insights into the microbial quality of marinated beef products aligning with general consumer preferences for natural food additives that can prolong the shelf life of foods.