Preparation method of sterilized milk

Abstract

The present invention provides a preparation method of sterilized milk. The preparation method is as follows: raw milk in line with national food safety standards is subjected to impurity removing via a milk purifying machine and then the impurity removed milk is homogenized at 15-20 MPa; then the homogenized milk and a direct injection steam are subjected to mixed atomization: the high temperature atomization is used in the whole process, the raw milk is subjected to the nozzle atomization at a pressure of 50 MPa, then at the same time, the direct injection steam is pumped in, the steam pressure is 0.3-0.5 MPa, the steam temperature is 142.9 DEG C-158.1 DEG C, and the mixing time is 3-5 seconds; flash evaporation concentration: the process is conducted in a flash evaporation tank, a part of water of the materials is evaporated under negative pressure, and the temperature of the materials is lowered to be 70 DEG C or below within 5 seconds; and the materials are subjected to aseptic packaging to obtain the finished products. The preparation method of the sterilized milk retains most of the nutrients in the raw milk and microorganisms in the finished products meet the requirements of commercial sterilization.

Description

technical field [0001] The invention relates to a method for preparing sterilized milk, in particular to a method for preparing sterilized milk by using direct injection steam. Background technique [0002] Liquid milk is made from raw milk, milk powder, etc., through proper processing, to make liquid commercial milk that can be directly consumed by consumers. There are many types of liquid milk: pasteurized milk, fresh-keeping milk, ultra-high temperature sterilized milk and retained sterilized milk. These liquid dairy products must be sterilized at different temperatures during the processing process. Different sterilization processes directly lead to different microbial indicators in the products, which are directly related to the shelf life of the products. If we blindly pursue the shelf life, increase the sterilization temperature, and increase the sterilization time, the nutrients in the product will be destroyed by high temperature. Although pasteurization can keep m...

AI Technical Summary

Problems solved by technology

If we blindly pursue the shelf life, increase the sterilization temperature, and increase the sterilization time, the nutrients in the product will be destroyed by high temperature. Although pasteurization can keep most of the nutrients from being destroyed, some heat-resistant bacteria still survive in the material. , it is difficult to guarantee the long-term preservation of the product