Non-thermal Ozone Pasteurization of a Ginger Root Product

To produce a ready-to-eat, preservative-free ginger root product, a non-thermal pasteurization applying ozone in water at pH 3.0 was developed. The sterilization effect by the ozone treatment was studied. Both of the curves of ozone solubility in water and seasoning liquid fitted the Logistic model. The ozone saturation concentrations in water and the seasoning liquid at 16-17℃ were 0.852 mg·L-1 and 1.920 mg·L-1, respectively. Ozone was fed at a rate of 33.34 mg·min-1·L-1. Ginger roots were submerged in water at pH 3.0 and in the seasoning liquid with the ozone-feeding for 15 and 20 minutes. The bacteria, mould and yeast counts in the product were less than 10 CFU·g-1 yielding a sterilization rate of greater than 99.9%. The hygiene index of the ready-to-eat ginger product met the standards for pickles stipulated under GB 2714-2003.