Beyond Chemical Preservatives: Enhancing the Shelf-Life and Sensory Quality of Ready-to-Eat (RTE) Hummus with Vinegar and Other Natural Antimicrobials

Abstract

Hummus is a traditional and very popular Mediterranean ready-to-eat (RTE) food, with growing popularity worldwide. However, it has a high water activity and is susceptible to microbial growth and post-process contamination that limit its quality and shelf-life. For this purpose, the present study compared the use of several antimicrobials, alone or in combination, for hummus preservation during storage (4 °C), for up to 45 days. The chemical preservative potassium sorbate 0.09% (S) was evaluated, along with three natural antimicrobials: garlic 1.25% (G); vinegar 5% (V); natamycin 0.002% (N); or their combination: garlic 1.25%-vinegar 5% (GV); vinegar 5%-natamycin 0.002% (VN); garlic 1.25%-natamycin 0.002% (GN); and garlic 1.25%-vinegar 5%-natamycin 0.002% (GVN) to increase the shelf-life of hummus. A thymol and carvacrol mixture 0.2% (O) was also assessed to preserve and develop a new oregano-flavored hummus. All treatments that included vinegar used alone or in combination had significantly higher antimicrobial effectiveness than the other treatments. They achieved 2.2-3.2, 1.8-3.1, and 1.4-2.1 log reductions in total aerobic counts (TAC), Pseudomonas spp., and lactic acid bacteria (LAB), respectively, as compared to the control samples © at day 21. Therefore, the shelf-life of C, S, N, G, GN, and O was around (ca.) 19 days, compared to an extended one of ca. 25 days for V and VN, and ca. 30 days for GV and GVN. Sensory analysis showed the highest acceptability for C, N, S, V, and VN, followed by GV and GVN, and the lowest was for G, GN, and finally O. The findings provide potential alternatives to chemical preservatives, which could be used for natural hummus preservation and shelf-life extension.