Optimization of extraction conditions of pulsed light parameters for enhanced sterilization of mould on pasteurized milk by response surface methodology

To study the sterilization effect of the pulsed light sterilization technology to the pasteurized milk, pasteurized milk as the research object, with the sterilization rate of mould as a measure indicator.Four extraction parameters including flash times, flash distance, flash energy and samples liquid thickness were optimized using central composite design and response surface methodology based on single factor investigation for achieving maximum the sterilization rate of mould. Using Box- benhnken central composite design and response surface analysis theory, the optimum extraction condition for flash times of 20, flash distance of 12.8cm, flash energy of 300 J and samples liquid thickness of 2mm.Under these conditions, the sterilization rate of mould was 99.97%.By means of electronic nose analysis and determination.Odor information of two milk sample were analyzied and judged by linear discriminant analysis ( LDA) .Using the Alphasoft software, it was found that the shelf life of milk sample were5 d and 7d before and after pulsed light treatment. Plused light sterilization technology can extend the shelf life of pasteurized milk effectively.