Effect of sterilization methods on the flavor of cold brew coffee

Abstract

This research used ultra-fast E-nose, E-tongue and SCA analysis to explore the effects of different sterilization methods (pasteurization, back pressure sterilization, high temperature short-term sterilization, membrane filtration treatment and high pressure processing) on cold brew coffee. The results showed that non-heat sterilization can better maintain the sensory quality of coffee liquid. Back pressure sterilization could reduce the pH value of coffee liquid to 4.65, and decrease the aroma content significantly by 50.5% (p < 0.05), while the sourness and bitterness of coffee samples increased, which lowered the sensory quality of coffee. Among the heat sterilization treatments, high temperature short-term sterilization had relatively little effect on the sensory quality of the coffee beverage, and decreased the bitterness of the coffee. Taking sensory quality, nutrients and cost into consideration, it is suggested that high temperature short time sterilization is a prefered method. Thus, the results of this research provided a theoretical basis for the selection of sterilization method for cold brew coffee.