Behaviour of non-stressed and stressed Listeria monocytogenes and Campylobacter jejuni cells on fresh chicken burger meat packaged under modified atmosphere and inoculated with protective culture

• Published in: International journal of food microbiology Vol. 158; no. 2; pp. 107 - 112
• Main Authors: Melero, Beatriz, Diez, Ana M., Rajkovic, Andreja, Jaime, Isabel, Rovira, Jordi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 17.08.2012
• Subjects: administration & dosage; aerobic conditions; air; Animals; Atmosphere; Campylobacter jejuni; Campylobacter jejuni - growth & development; Carbon dioxide; Cell culture; Chicken meat; Chickens; Colony Count, Microbial; Colony-forming cells; Consumers; drug effects; Food; Food Contamination; Food Contamination - prevention & control; Food Packaging; Food Preservation; Food Preservation - methods; food safety; Freeze stress; Freeze-thawing; Freezing; freezing point; growth & development; Leuconostoc; Leuconostoc pseudomesenteroides; Leuconostoc pseudomesenteroides PCK 18; Listeria monocytogenes; Listeria monocytogenes - drug effects; Listeria monocytogenes - growth & development; Meat; Meat - microbiology; Meat Products; Meat Products - microbiology; methods; microbiology; modified atmosphere packaging; prevention & control; Probiotics; Probiotics - administration & dosage; Protective culture; raw meat; Refrigeration; Shelf life; Stress; Temperature effects; Protective culture; Leuconostoc pseudomesenteroides PCK 18; Chicken meat; MAP; Freeze stress
• ISSN: 0168-1605; 1879-3460; 1879-3460
• DOI: 10.1016/j.ijfoodmicro.2012.07.003

Numerous investigations have provided evidence that chicken products are a source of Listeria monocytogenes and Campylobacter jejuni. Different strategies applied in final products are needed to prevent consumers' contamination. In this work, the combination of modified atmosphere packaging (MAP) and protective culture to control the growth of freeze stressed and non-stressed L. monocytogenes and C. jejuni on fresh chicken meat burger was studied. Meat burgers were inoculated with L. monocytogenes, C. jejuni and Leuconostoc pseudomesenteroides PCK 18, as protective strain against L. monocytogenes. Prior to the addition of the protective culture, half of the L. monocytogenes and C. jejuni — inoculated meat was frozen at −18°C for 48h to subject cells to stress. Following the addition of the protective culture, meat burgers were packaged in air or MAP (50% CO2/50% O2) and stored under refrigeration conditions. L. monocytogenes counts were not reduced by the freezing temperature applied; however, the addition of Lc. pseudomesenteroides PCK 18 reduced its counts for 0.90 log cfu/g when chicken meat burgers were packaged under MAP. Furthermore, freezing stress was an effective strategy to reduce C. jejuni counts but only in combination with a high-O2 MAP, it was completely eliminated. Chicken meat burgers’ shelf-life under aerobic packaging conditions was reduced by the effect of freeze-thawing, while the use of MAP extended the product's shelf-life till 21days. Therefore, the combination of freezing, protective culture and MAP could extend the shelf-life and enhance the food safety of this kind of chicken products. ► Listeria monocytogenes and Campylobacter jejuni are detected in chicken meat burgers. ► The combination of MAP, protective culture and freeze stress was evaluated. ► The three strategies were effective to eliminate the risk of C. jejuni. ► The three strategies were effective to reduce the level of L. monocytogenes.