超高压灭菌效果实验研究

超高压灭菌技术是一项具有广阔应用前景的食品加工新技术。本文以食品中常见的大肠杆菌、枯草芽孢杆菌为研究对象,通过实验对影响超高压灭菌效果的处理条件(压力、保压时间、pH值等)进行了考察与评价。实验结果表明:压力、保压时间对灭菌效果影响显著,随着压力的增大和时间的增长,细菌的死亡率增大。但当处理压力和和保压时间达到一定值后,它所对灭菌效果的影响趋于平缓。强的酸性和碱性环境中,即在低pH值和高pH值时,有利于超高压杀菌,在中性环境中,灭菌效果最差。同时,本文对超高压处理后大肠杆菌的活性进行了研究,得出大肠杆菌经超高压处理后活性降低的结论。研究结果对进一步优化超高压杀菌工艺具有一定的参考价值。

Experimental Investigation of the Ultra-high Pressure Sterilization

The ultra-high pressure sterilization is a novel method for food processing and has a promising future in food industry. Several influencial parameters in the sterilization with this method, including processing pressure, sustaining time and pH value, are studied using Escherichia coli and Bacillus subtilis, which commonly exist in foods, as the objects of the experiments. The results indicate that the reductions of microorganisms increase with an increase of processing pressure and sustaining time. While the effects of high-pressure and sustaining time on Microorganisms vary gently after they reach a certain value. A acidic medium or alkaline medium are helpful for high pressure sterilization, and the neutral circumstance is the last choice for it. We also have studied the activity of Bacteria after high-pressure sterilization. The results show that the activity of Escherichia coli reduces after high-pressure treatment. The study provides some valuable references to optimize of high-pressure sterilization process.