Research on the Effect of Electron Beam Irradiation on Microorganism and Quality of Salad Dressing

Abstract

To provide reference for technical feasibility and process setting of physical cold disinfection of salad dressing, the commercial salad dressing was irradiated by electron beam at different doses of 0 kGy,1 kGy and 2 kGy. The disinfection effect of electron beam irradiation on salad dressing and the changes in terms of microorganism, color, texture, flavor, stability of irradiated salad dressing after storing for 40 days at room temperature were studied. The results showed that, electron beam irradiation had a good disinfection effect on Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, the aerobic plate count, molds and yeasts of salad dressing. 1 kGy irradiation could reduce pathogenic bacteria by 3 log to 6 log, with no aerobic plate count, molds and yeasts found. After 40 days storage at room temperature, sensory evaluation showed that electron beam irradiation at 1 kGy had no significant effect on the color, texture, aroma and taste of salad dressing. There was no obvious difference in the results of electronic nose analysis, texture parameters and centrifugal resolution rate, but the taste score of 2 kGy irradiation was significantly lower than that of non-irradiation and 1 kGy irradiation. Significant difference of texture parameters was found between 2 kGy irradiation, non-irradiation, and 1 kGy irradiation. Therefore, we conclude electron beam irradiation can effectively control the pathogenic bacteria in salad dressing. The electron beam irradiation at doses of 1 kGy has no obvious undesirable effect on the color, texture, flavor, stability of the salad dressing, which could be used as a disinfection method for salad dressing.

Keywords

• salad dressing
• electron beam irradiation
• disinfection
• color
• texture
• flavor
• sensory evaluation