Combination effect of Alpinia malaccensis and Terminalia catappa extract for controlling foodborne pathogens and spoilage bacteria on ready to cook vacuum packed raw chicken meat

Practical applications The combined antibacterial activity of Alpinia malaccensis and Terminalia catappa, was tested for Listeria monocytogenes, Staphylococcus aureus and spoilage bacteria in vacuum packed ready-to-cook (RTC) chicken. The 10 g of chicken pieces were inoculated with each bacterium and marinated with 0.5 ml of the mixture of 5 mg/ml A. malaccensis and 20 mg/ml T. catappa. The chicken was vacuum packed after adding 1 ml extract mixture and stored at 4 or 8 degrees C for 12 days. Every three-day intervals microbial count, lipid oxidation, pH, and the color was determined. Combination of plant extracts significantly (p < .05) inhibited the growth of S. aureus bacteria with 1.80, 2.13, 2.36, and 2.97 log CFU/g reduction over 3, 6, 9, and 12 days stored at 8 degrees C. Similarly, L. monocytogenes was significantly (p < .05) inhibited at 6, 9, 12 days with 1.22, 1.60, and 1.55 log CFU/g reduction compared to control at 4 degrees C. Lipid oxidation significantly reduced (p < .05) in treated chicken 1.39 MDA mg/kg and 2.43 MDA mg/kg at day 12 at 4 and 8 degrees C, respectively. Total plate count of treated chicken showed 6.59 +/- 0.10 log CFU/g at 6 days of storage at 4 degrees C and 6.66 +/- 0.36 CFU/g during 9 days of storage at 8 degrees C allowing safe for human consumption. The shelf-life of RTC marinated vacuum packed fresh chicken samples stored at 4 and 8 degrees C were significantly extended for 6 and 9 days, respectively. Plant extracts combination showed a significant inhibition of L. monocytogenes or S. aureus and spoilage bacteria and reduced lipid oxidation. Therefore, two plants extract combinations act as antimicrobials and antioxidants which could stabilize lipid oxidation, color, and microbial growth thus extending the shelf-life of ready to cook fresh chicken meat products. Therefore, marinated RTC chicken is economically important for the food industry.