Department of Agricultural and Environmental Sciences, Tennessee State University, Nashville, TN 37209, USA.
Department of Agricultural and Environmental Sciences, Tennessee State University, Nashville, TN 37209, USA.
Food Res Int. 2018 Jan;103:59-67. doi: 10.1016/j.foodres.2017.10.004. Epub 2017 Oct 4.
A continuous-flow UV reactor operating at 254nm wave-length was used to investigate inactivation of microorganisms including bacteriophage in coconut water, a highly opaque liquid food. UV-C inactivation kinetics of two surrogate viruses (MS2, T1UV) and three bacteria (E. coli ATCC 25922, Salmonella Typhimurium ATCC 13311, Listeria monocytogenes ATCC 19115) in buffer and coconut water were investigated (D values ranging from 2.82 to 4.54mJ·cm). A series of known UV-C doses were delivered to the samples. Inactivation levels of all organisms were linearly proportional to UV-C dose (r>0.97). At the highest dose of 30mJ·cm, the three pathogenic organisms were inactivated by >5 log (p<0.05). Results clearly demonstrated that UV-C irradiation effectively inactivated bacteriophage and pathogenic microbes in coconut water. The inactivation kinetics of microorganisms were best described by log linear model with a low root mean square error (RMSE) and high coefficient of determination (r>0.97). Models for predicting log reduction as a function of UV-C irradiation dose were found to be significant (p<0.05) with low RMSE and high r. The irradiated coconut water showed no cytotoxic effects on normal human intestinal cells and normal mouse liver cells. Overall, these results indicated that UV-C treatment did not generate cytotoxic compounds in the coconut water. This study clearly demonstrated that high levels of inactivation of pathogens can be achieved in coconut water, and suggested potential method for UV-C treatment of other liquid foods.
This research paper provides scientific evidence of the potential benefits of UV-C irradiation in inactivating bacterial and viral surrogates at commercially relevant doses of 0-120mJ·cm. The irradiated coconut water showed no cytotoxic effects on normal intestinal and healthy mice liver cells. UV-C irradiation is an attractive food preservation technology and offers opportunities for horticultural and food processing industries to meet the growing demand from consumers for healthier and safe food products. This study would provide technical support for commercialization of UV-C treatment of beverages.
研究使用波长为 254nm 的连续流动紫外线反应器，研究了包括椰子水中噬菌体在内的微生物的失活动力学，椰子水是一种高度不透明的液体食品。研究了两种替代病毒（MS2、T1UV）和三种细菌（E.coli ATCC 25922、鼠伤寒沙门氏菌 ATCC 13311、李斯特菌 monocytogenes ATCC 19115）在缓冲液和椰子水中的 UV-C 失活动力学（D 值范围为 2.82 至 4.54mJ·cm）。向样品输送一系列已知的 UV-C 剂量。所有生物体的失活水平与 UV-C 剂量呈线性比例（r>0.97）。在最高剂量 30mJ·cm 下，三种病原体被灭活>5 对数（p<0.05）。结果清楚地表明，UV-C 照射有效地灭活了椰子水中的噬菌体和病原体微生物。微生物的失活动力学最好用对数线性模型来描述，该模型具有较低的均方根误差（RMSE）和较高的决定系数（r>0.97）。发现预测 UV-C 照射剂量与对数减少之间关系的模型具有显著意义（p<0.05），RMSE 低，r 高。辐照椰子水对正常人类肠道细胞和正常小鼠肝细胞没有细胞毒性作用。总体而言，这些结果表明，UV-C 处理不会在椰子水中产生细胞毒性化合物。这项研究清楚地表明，在椰子水中可以实现高水平的病原体失活，并为 UV-C 处理其他液体食品提供了潜在方法。
本研究论文提供了科学证据，证明在商业相关剂量 0-120mJ·cm 下，UV-C 照射可有效灭活细菌和病毒的替代物。辐照椰子水对正常肠道和健康小鼠肝脏细胞没有细胞毒性作用。UV-C 照射是一种有吸引力的食品保存技术，为园艺和食品加工业提供了机会，以满足消费者对更健康、更安全食品产品的需求不断增长。本研究将为 UV-C 处理饮料的商业化提供技术支持。
