Antimicrobial effects of chitosan and garlic against Salmonella spp., Escherichia coli O157:H7, and Listeria monocytogenes in hummus during storage at various temperatures

• Published in: Journal of food science Vol. 87; no. 2; pp. 833 - 844
• Main Authors: Osaili, Tareq M., Al‐Nabulsi, Anas A., Hasan, Fayeza, Olaimat, Amin N., Taha, Sadi, Ayyash, Mutamed, Nazzal, Dima S., Savvaidis, Ioannis N., Obaid, Reyad S., Holley, Richard
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.02.2022
• Subjects: Anti-Infective Agents; Antiinfectives and antibacterials; antimicrobial; Antimicrobial activity; Antimicrobial agents; chickpea dip; Chitin; Chitosan; Chitosan - pharmacology; Colony Count, Microbial; E coli; Escherichia coli; Escherichia coli O157; Food Microbiology; foodborne pathogens; Garlic; Hummus; Listeria; Listeria monocytogenes; Microorganisms; Natural polymers; natural preservatives; Polymers; Safety; Salmonella; Temperature; temperature abuse; antimicrobial; chickpea dip; temperature abuse; foodborne pathogens; natural preservatives
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/1750-3841.16025

The study aimed to evaluate the antimicrobial activity of 0.5 or 1% (w/w) chitosan and 1% (w/w) garlic against Salmonella spp., Escherichia coli O157:H7 and Listeria monocytogenes in hummus dip stored at 4, 10, or 25°C for 28, 21, or 7 days, respectively. In hummus without garlic, at all storage temperatures and storage periods, 0.5% chitosan decreased Salmonella spp., E. coli O157:H7, and L. monocytogenes by 0.9–2.3, 0.6–2.3, and 0.9–1.3 log CFU/g, respectively. In comparison, 1% chitosan decreased the numbers by 1.6–2.9, 1.4–2.7, and 1.3–1.8 log CFU/g, respectively. In hummus with 1% garlic, 0.5% chitosan decreased Salmonella spp., E. coli O157:H7, and L. monocytogenes by 0.7–2.5, 0.6–2.2, and 1.0–1.5 log CFU/g, respectively. Furthermore, 1% chitosan decreased the numbers by 1.6–2.8, 1.2–2.7, and 1.5–1.6 log CFU/g, respectively. With few exceptions, adding 1% garlic to hummus did not result in any significant reduction (at p < 0.05) in microbial numbers. The greatest decreases of Salmonella spp., E. coli O157:H7, and L. monocytogenes were 3.1, 3.6, and 2.9 log CFU/g with 1% chitosan held at 4°C for 28 days. The highest overall acceptability was for hummus with 0.5% chitosan + 1% garlic. Commercial use of chitosan is expected to help producers improve hummus safety. Practical Application Hummus is consumed worldwide as a dip due to its taste and health benefits. Microbial safety of hummus can be enhanced by incorporating chitosan, derived from the natural polymer chitin, into the formulation. This enhanced recipe would be a bonus for producers and consumers alike.