Zeitoun,, A. (2000). UTILIZATION OF CARROT JUICE TO INHIBIT Listeria monocytogenes. Journal of Food and Dairy Sciences, 25(2), 921-930. doi: 10.21608/jfds.2000.258562
A. A. Zeitoun,. "UTILIZATION OF CARROT JUICE TO INHIBIT Listeria monocytogenes". Journal of Food and Dairy Sciences, 25, 2, 2000, 921-930. doi: 10.21608/jfds.2000.258562
Zeitoun,, A. (2000). 'UTILIZATION OF CARROT JUICE TO INHIBIT Listeria monocytogenes', Journal of Food and Dairy Sciences, 25(2), pp. 921-930. doi: 10.21608/jfds.2000.258562
Zeitoun,, A. UTILIZATION OF CARROT JUICE TO INHIBIT Listeria monocytogenes. Journal of Food and Dairy Sciences, 2000; 25(2): 921-930. doi: 10.21608/jfds.2000.258562
UTILIZATION OF CARROT JUICE TO INHIBIT Listeria monocytogenes
Dept. of Food Sci., Fac. of Agric. (Saba Basha), Univ. of Alex. Egypt.
Abstract
The antibacterial effect of the carrot juice and the distillate of carrot juice, against two strains of Listeria monocytogenes (Listeriamonocytogenes Z7 and Listeria monocytogenes B4) were investigated (in vitro). Fresh minced meat was inoculated with L.m. B4 at level of 3.52 log10 CFU/g of minced meat. The inoculated samples were subjected to treat with 0.6% of carrot juice and stored at 4 and 24°C to study the effect of carrot juice on Listeria monocytogenes B4 (in vivo). Psychrotrophic aerobic bacteria and pH of minced meat were determined during storage period at 4 and 24°C. The chemical composition of minced beef meat were also determined. Results revealed that the antimicrobial effect of carrot juice against Listeria monocytogenes (L.m. Z7 and L.m. B4) increased with increasing concentration of carrot juice. The carrot juice was bacteriostatic at concentration of 0.4% (v/v) and was bacteriocidal above this concentration. There was a significant difference (P < 0.05) between the concentration of 0.5% and 0.6% (v/v), meanwhile there was no significant difference (P > 0.05) between the concentration of 0.6 and 0.7% (v/v) for both strains of L.m. used in this study. In contrast, the distillate of carrot juice did not show any antimicrobial effects against both strains of L.m. at the concentrations tested. Meat pH ranged from 6.11 (Freshness) to 7.41 (Frank spoilage). The increase in pH value during storage was more pronounced at 24°C than at 4°C. The treatment of minced meat with 0.6% carrot juice resulted in a reduction of the number of L.m. B4 on minced meat from log10 CFU/g = 3.52 to 1.55 after 5 days of storage at 4°C. After 1, 2, 3, 4 and 5 days of storage at 4°C, the number of L.m. on samples treated with 0.6% of carrot juice was significantly lower as compared with the number on control samples. Likewise the use of 0.6% carrot juice showed antimicrobial effect against L.m. on minced meat stored at 24°C. However the effect was more pronounced at 4°C than at 24°C. Minced meat stored at 4 and 24°C, showed shelf life of 4 days and 14 hr respectively. Followed by off odours on day 5 and at 15 hr respectively.