Department of Agricultural and Biological Engineering (ORCID: https://orcid.org/0000-0002-2049-5026 [A.D.]).
The Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
J Food Prot. 2020 Mar 1;83(3):418-425. doi: 10.4315/0362-028X.JFP-19-386.
Unpasteurized liquid egg can be contaminated with pathogenic microorganisms and may cause foodborne outbreaks. Thus, it is essential to decontaminate the liquid egg to ensure food safety. Pulsed UV light is one of the emerging technologies for food decontamination in recent years. This static treatment system has been studied previously in our laboratory. However, continuous processing using a flow-through treatment system needs to be evaluated for potential commercial applications. Therefore, in this study, a flow-through treatment system of pulsed UV light was evaluated and optimized for inactivation of Escherichia coli K12NSR for liquid egg white decontamination. Treatment factors including flow rate (40 to 80 mL/min), number of passes (one to three passes), and distance from the sample to the pulsed UV light strobe (5 to 13 cm) were optimized using response surface methodology. This methodology suggested three passes with 40 mL/min flow rate and a 5-cm distance as the optimum conditions. The model was then validated for the maximum reduction of E. coli K12NSR, which was measured as 1.57 log CFU/mL at the optimal conditions. The energy doses of the pulsed UV light and temperature changes of the liquid egg white during the treatment were measured. Furthermore, several quality parameters were assessed at the optimum treatment conditions to determine the impact of the flow-through pulsed UV processing on the quality of liquid egg white. The results showed significant differences in pH, lipid oxidation, turbidity, and color between control and pulsed UV light-treated samples (P < 0.05). However, there was no significant difference in foaming ability or foam stability between pulsed UV light-treated samples and the control. Overall, this study demonstrated the potential of flow-through pulsed UV light to decontaminate liquid egg white, but further research is needed for optimal enhancement.
未经巴氏消毒的液态蛋可能受到致病微生物的污染，并可能导致食源性疾病爆发。因此，对液态蛋进行消毒以确保食品安全至关重要。脉冲紫外光技术是近年来食品消毒的新兴技术之一。本实验室之前已经对该静态处理系统进行了研究。然而，需要对连续处理的流动式处理系统进行评估，以考察其在潜在商业应用中的效果。因此，在本研究中，对用于液态蛋清消毒的脉冲紫外光流动式处理系统进行了评估和优化。使用响应面法对处理因素（流速（40 至 80 毫升/分钟）、通过次数（一次至三次）和样品到脉冲紫外光频闪灯的距离（5 至 13 厘米））进行了优化。该方法建议使用 40 毫升/分钟的流速和 5 厘米的距离进行三次通过作为最佳条件。然后对该模型进行了验证，以实现对 E. coli K12NSR 的最大减少量，在最佳条件下，E. coli K12NSR 的减少量测量值为 1.57 对数 CFU/mL。测量了脉冲紫外光的能量剂量和液态蛋清在处理过程中的温度变化。此外，在最佳处理条件下评估了几个质量参数，以确定流动式脉冲紫外处理对液态蛋清质量的影响。结果表明，处理前后的 pH 值、脂质氧化、浊度和颜色存在显著差异（P < 0.05）。然而，在脉冲紫外光处理的样品和对照样品之间，起泡能力或泡沫稳定性没有显著差异。总体而言，本研究表明流动式脉冲紫外光有潜力对液态蛋清进行消毒，但需要进一步研究以实现最佳增强效果。
