Potential Bacterial Health Risk Posed to Consumers of Fresh Coconut (Cocos nucifera L.) Water

Adolf K. Awua, Edna D. Doe, Rebecca Agyare

Cellular and Clinical Research Centre, Radiological and Medical Sciences Research Institute, Ghana Atomic Energy Commission, Accra, Ghana.

DOI: 10.4236/fns.2012.38149                

Abstract

Coconut (Cocos nucifera L.) water is a refreshing drink consumed mostly directly from the fruit. However, in recent times, consumers in Accra prefer to have it transferred into plastic bags for later consumption; this favours a high risk of bacterial contamination. Since it is rich in nutrient, it may become unwholesome with possible high bacteria loads. However, its use for managing and preventing diarrhoeal diseases and the report that coconut water contains anti-bacterial proteins, suggests a bacteria growth inhibition potential for it. Therefore, the propensity of fresh coconut water to support the growth of two pathogenic bacteria was studied. Using mostly optical density measurement, and where possible, growth parameters and bacteria loads were estimated for the growth of two gram negative bacteria in fresh, stored and sterilized coconut water, and also in Luria-Bertani (LB) broth as a control. The study revealed that fresh coconut water is a drink favourable for the survival and growth of Escherichia coli, and Klebsiella pneumoniae. It supported the growth of these bacteria recording lag times of 101.4 ± 1.00 minutes for E. coli and 154.8 ± 0.45 minutes for K. pneumoniae, and high loads of viable cells of ~ 2.27 × 10⁸ cfu/mL and > 2.83 × 10⁸ cfu/mL at the stationary phase for E. coli and K. pneumoniae respectively. These and other growth parameters in coconut water were comparable to those in Luria-Bertani (LB) broth medium. However, when autoclaved, gamma irradiated or stored at 4℃ for two weeks or more, the growth of these bacteria becomes extremely limited. Fresh coconut water will support the growth of these bacteria to high and infective load of viable cell if it becomes contaminated with and is kept at ambient temperatures for two or more hours. Thus, it will be safer to consume coconut water directly from the fruit, since there is a high risk for bacteria contamination associated with the transfer and storage in other containers.

Keywords

Coconut Water; Bacterial Growth Curves; Health Risk

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	R. Kelly, “Ghana-Cholera outbreaks in 2011,” 2011. http://www.flutrackers.com/forum/showthread.php?t=159173
[2]	M. DebMandal and S. Mandal, “Coconut (Cocos nucifera L.: Arecaceae): In Health Promotion and Disease Prevention,” Asian Pacific Journal of Tropical Medicine, Vol. 1, 2011, pp. 241-247. doi:10.1016/S1995-7645(11)60078-3
[3]	A. M. Fonseca, F. J. Q Monte, M. da Conceic and F. de Oliveiraa ?o, “Coconut Water (Cocos nucifera L.)—A New Biocatalyst System for Organic Synthesis,” Journal of Molecular Catalysis B: Enzymatic, Vol. 57, 2009, pp. 78–82. doi:10.1016/j.molcatb.2008.06.022
[4]	E. H. M. Walter, D. Y. Kabuki, L. M. R. Esper, A. S. Sant’Ana and A. Y. Kuaye, “Modelling the Growth of Listeria monocytogenes in fresh Green Coconut (Cocos nucifera L.) Water,” Food Microbiology, Vol. 26, 2009, pp. 653-657. doi:10.1016/j.fm.2009.04.003
[5]	D. Campbell-Falck, T. Thomas, T. M. Falck, N. Tutuo and K. Clem, “The Intravenous Use of Coconut Water,” American Journal of Emergency Medicine, Vol. 18, No. 1, 2000, pp. 108-111. doi:10.1016/S0735-6757(00)90062-7
[6]	U. Santoso, K. Kubo, T. Ota, T. Tadokoro and A. Maekawa, “Nutrient Composition of Kopyor Coconuts (Cocos nucifera L.),” Food Chemistry, Vol. 57, No. 2, 1996, pp. 299-304. doi:10.1016/0308-8146(95)00237-5
[7]	A. G. Pue, W. Riva, K. Sundarao, C. Kaluarin and K. Singh, “Preliminary Studies on Changes in the Coconut Water during Maturation of the Fruit,” Science in New Guinea, Vol. 18, No. 2, 1992, pp. 81-84.
[8]	A. Jayalakshmy, C. Arumughan, C. S. Narayanan and A. G. Mathew, “Changes in the Chemical Composition of Coconut Water during Maturation,” Journal of Food Science and Technology, Vol. 23, No. 4, 1986, pp. 203-207.
[9]	S. M. Mandal, S. Dey, M. Mandal, S. Sarkar, S. Maria- Neto and O. L. Franco, “Identification and Structural Insights of Three Novel Antimicrobial Peptides Isolated from Green Coconut Water,” Peptides, Vol. 30, No. 4, 2009, pp. 633-637. doi:10.1016/j.peptides.2008.12.001
[10]	K. N. Matsui, J. A. W. Gut, P. V. de Oliveira and C. C. Tadini, “Inactivation Kinetics of Polyphenol Oxidase and Peroxidase in Green Coconut Water by Microwave Processing,” Journal of Food Engineering, Vol. 88, No. 2, 2008, pp. 169-176. doi:10.1016/j.jfoodeng.2008.02.003
[11]	K. V. Reddy, M. Das and S. K. Das, “Filtration Resis- Tances in Non-Thermal Sterilization of Green Coconut Water,” Journal of Food Engineering, Vol. 69, 2005, pp. 381-385. doi:10.1016/j.jfoodeng.2004.08.029
[12]	A. K. Awua, E. D. Doe and R. Agyare, “Exploring the Influence of Sterilisation and Storage on Some Physico- Chemical Properties of Coconut (Cocos nucifera L.) Water,” BMC Research Notes, Vol. 4, 2011, pp. 451-454. doi:10.1186/1756-0500-4-451.
[13]	J. G. Fox, “Nutrition: Decontamination of Diets,” In: J. G. Fox, S. W. Barthold, M. T. Davisson, C. E. Newcomer, F. W. Quimby and A. L. Smith, Eds., The Mouse in Biomedical Research, 2nd Edition, Academic Press, Millbrae, 2007, pp. 362-364.
[14]	Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food, “Report of the Working Party on Irradiation of Food,” WHO Technical Report Series, No.659, Geneva, 1981.
[15]	E. N. Onyeike and T. T. Omubo-Dede “Effect of Heat Treatment on the Proximate Composition, Energy Values, and Levels of Some Toxicants in African Yam Bean (Sphenostylis stenocarpa) Seed Varieties,” Plant Foods for Human Nutrition, Vol. 57, No. 3-4, 2002, pp. 223-231. doi:10.1023/A:1021833516234
[16]	H. S. Rehan and B. G. Matapurka, “Tender Coconut Water: An Ideal Fluid for Parenteral Substitute,” Journal of Institute of Medicine, Vol. 21, 1999, pp. 1-57.
[17]	S. Divakaran, O. Decamp, J. J. Cody and W. G. Dominy, “Studies on Quality Changes in Shrimp Feeds Exposed to Gamma, E-Bem and X-Ray Irradiation,” Journal of Aquaculture in the Tropics, Vol. 17, 2002, pp. 1555-1165.
[18]	J. D. Greig, E. C. D. Todd and B. Michaels, “Infective Doses and Pathogen Carriage,” Proceedings of the 2010 Food Safety Education Conference, Atlanta, 23-26 March 2010. http://www.fsis.usda.gov/PDF/Atlanta2010/Slides_FSEC_JGreig_Doses.pdf
[19]	M. M. Cowan, “Plant Products as Antimicrobial Agents,” Clinical Microbiology Reviews, Vol. 12, No. 4, 1999, pp. 564-582.
[20]	N. C. Murasaki-Aliberti, R. M. S. da Silva, J. A. W. Gut and C. C. Tadini, “Thermal Inactivation of Poly-Phenoloxidase and Peroxidase in Green Coconut (Cocos nucifera) Water,” International Journal of Food Science & Technology, Vol. 44, 2009, pp. 2662-2668. doi:10.1111/j.1365-2621.2009.02100.x
[21]	X. Fan, D. W. Thayer and A. P. Handel, “Nutritional Quality of Irradiated Orange Juice,” Journal of Food Processing and Preservation, Vol. 26, No. 3, 2002, pp. 195-211. doi:10.1111/j.1745-4549.2002.tb00480.x.