Junyan Liu1, Lin Li2, Lizhen Zhou3, Bing Li2, Zhenbo Xu4. 1. School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, PR China; Department of Clinical Pharmacy, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA. 2. School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, PR China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, PR China. 3. School of Applied Chemistry and Biological Technology, Shenzhen Polytechnic, Shenzhen 518055, PR China. Electronic address: gzzhoulizhen@163.com. 4. School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, PR China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, PR China; Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA. Electronic address: zhenbo.xu@hotmail.com.
Abstract
OBJECTIVES: This study aimed to investigate the effect of different ultrasound treatment conditions on the inactivation of Saccharomyces cerevisiae with the application of response surface methodology (RSM). METHODS: Ultrasound treatment were applied on different concentrations of S. cerevisiae cells with different pH, temperature, ultrasound power, irradiating time, and pulse duty ratio. Cell viability was determined by plate counting method. Response surface methodology was used to analyze the correlation among various factors. RESULTS: Limited with low ultrasound power, lower pH value slightly improved the ultrasound treatment efficiency. Also, higher nonlethal temperature and ultrasound power, longer irradiation time, and lower pulse duty ratio facilitated the inactivation of S. cerevisiae. Cell concentration had no effect on ultrasound efficiency. CONCLUSIONS: Ultrasound power played the most important role in the ultrasound irradiation process according to RSM analyses. Information derived from this study may aid in the control of the sublethal injury of S. cerevisiae during ultrasound treatment in food industry.
OBJECTIVES: This study aimed to investigate the effect of different ultrasound treatment conditions on the inactivation of Saccharomyces cerevisiae with the application of response surface methodology (RSM). METHODS: Ultrasound treatment were applied on different concentrations of S. cerevisiae cells with different pH, temperature, ultrasound power, irradiating time, and pulse duty ratio. Cell viability was determined by plate counting method. Response surface methodology was used to analyze the correlation among various factors. RESULTS: Limited with low ultrasound power, lower pH value slightly improved the ultrasound treatment efficiency. Also, higher nonlethal temperature and ultrasound power, longer irradiation time, and lower pulse duty ratio facilitated the inactivation of S. cerevisiae. Cell concentration had no effect on ultrasound efficiency. CONCLUSIONS: Ultrasound power played the most important role in the ultrasound irradiation process according to RSM analyses. Information derived from this study may aid in the control of the sublethal injury of S. cerevisiae during ultrasound treatment in food industry.