Food Protection Trends - March 2009 - 159

TABLE 2. Population of Salmonella in beef and chicken broth samples treated with 5% chive extract after incubation at 37°C for 48 h Food sample Bacterial population (log CFU/ml) Initial Chicken broth without chive extract Chicken broth with chive extract Beef broth without chive extract Beef broth with chive extract 1 2 Final (48 h)1,2 7.40 ± 0.17b 1.78 ± 0.24a 8.67 ± 0.34c 2.10 ± 0.22a 3.11 ± 0.31 3.10 ± 0.19 3.19 ± 0.21 3.21 ± 0.19 Average of three replications Mean values in the same column followed by different letters are significantly different (P < 0.05) the growth of Salmonella or to the high buffering capacity of ingredients present in the beef extract that maintain neutral pH value during growth of Salmonella. We believe this study represents the first published work to demonstrate the antimicrobial capacity of chive extract against Salmonella in a food model. Although our results demonstrate that chive extract has great potential for use as an antibacterial compound, we believe that chive extract could be more effective if combined with other natural ingredients or nonthermal processes. To date, several combinations of natural ingredients have been shown to inhibit the growth of disesase-causing microorganisms (3, 10–12). For example, lactic acid in combination with caffeine or copper could be used as an antimicrobial agent to inhibit growth of Escherichia coli O157:H7 (11, 15). The combination of copper and lactic acid also has a synergistic effect against Salmonella in BHI broth and carrot juice (12). The use of copper ion in combination with sodium hydrochloride (100 ppm) followed by sonication (44 to 48 kHz) caused a 5-log reduction of E. coli O157:H7 and Listeria monocytogenes is in apple cider (17). A combination of ultrasound and vanilla prevented the growth of L. monocytogenes is in orange juice (9). Extensive further studies on applications of combined treatments should be conducted to determine the inhibitory effects of different chive mixtures on other strains of Salmonella. Chives can be used as seasoning and can be incorporated into a variety of fresh and cooked foods in which a natural antimicrobial agent is needed. Its use is likely to be appealing to consumers because chives are natural and can be added to fresh food mixtures, especially those typically prepared with onion, without significantly altering the flavor. Results of this study suggest that further research should explore the potential antimicrobial effect of chives in other food systems, particularly fresh greens. Sensory analysis studies of foods are also needed to determine if concentrations sufficient to inhibit growth effectively or eliminate foodborne pathogens would change the taste characteristics of the original food. ACKNOWLEDGMENTS The research work was funded, in part, through the Cooperative State Research, Education and Extension Service of the United States Department of Agriculture, in the Agricultural Research Program, North Carolina Agricultural and Technical State University. We express our gratitude to Dr. C. S. Turner, Associate Dean for Research, for her support and to Dr. K. J. Gruber for his review and comments on this manuscript. REFERENCES 1. Abbas, S. M., and A. K. Halkman. 2004. Antimicrobial effect of water extract of sumac (Rhus coriaria L.) on the growth of some food borne bacteria including pathogens. Int. J. Food Microbiol. 97:63–69. 2. Aktug, S. E., and M. Karapinar. 1986. Sensitivity of some common food poisoning bacteria to thyme, mint and bay leaves. Int. J. Food Microbiol. 3: 349–354. 3. Alzoreky, N. S., and K. Nakahara. 2003. Antibacterial activity of extracts from some edible plants commonly consumed in Asia. Int. J. Food Microbiol. 80:223–230. 4. Anonymous. Economics of foodborne disease: estimating the benefits of reducing foodborne disease. US Department of Agriculture, Economic Research Service. Available at http://www.ers.usda.gov/ briefing/foodborneDisease/features.htm Accessed 20 November 2006. 5. Block, E., S. Naganathan, D. Putman, and S. H. Zhao. 1992. Allium chemistry: HPLC analysis of thiosulfinates from onion, garlic, wild garlic (ramsons), leek, scallion, shallot, elephant (great-headed) garlic, chive, and Chinese chive. Uniquely high allyl to methyl ratios in some garlic samples. J. Agric. Food Chem. 40:2418–2430. 6. Cavallito, C. J., J. S. Buck, and C. M. Suter. 1944a. Allicin, the antibacterial principle of Allium sativum, I. Isolation, physical properties and antibacterial action. J. Am. Chem. Soc. 66:1950–1951. 7. Cavallito, C. J., J. S. Buck, and C. M. Suter. 1944b. Allicin, the antibacterial principle of Allium sativum, II. Determination of the structure. J. Am. Chem. Soc. 66:1952–1955. 8. Chitsiri, T., P. M. Davidson, W. Mahakarnchanakul, and P. Vibulsresth. 2005. Antimicrobial effect of Thai spices against Listeria monocytogenes and Salmonella Typhimurium DT104. J. Food Prot. 68:2054–2058. 9. Ferrante, S., S. Guerrero, and S. M. Alzamora. 2007. Combined use of ultrasound and natural antimicrobi- MARCH 2009 | FOOD PROTECTION TRENDS 159

http://www.ers.usda.gov/briefing/foodborneDisease/features.htm http://www.ers.usda.gov/briefing/foodborneDisease/features.htm http://www.ers.usda.gov/briefing/foodborneDisease/features.htm

Food Protection Trends - March 2009

Table of Contents for the Digital Edition of Food Protection Trends - March 2009