Two-stage fermentation preparation technique of yogurt rich in conjugated linoleic acid (CLA)

Abstract

The invention relates to the field of biological food and discloses a technique of producing conjugated linoleic acid (CLA) yogurt through two-stage fermentation of lactobacillus. According to the technique, lactobacillus bulgaricus and streptococcus thermophilus are utilized for producing fermented milk, and then lactobacillus reuteri is inoculated for second-stage fermentation, thereby preparing the yogurt rich in CLA, wherein CLA is a non-exogenous additive substance generated by fermentation of lactobacillus, and the production cost is lowered. During production of the CLA yogurt through the two-stage fermentation method, in the first stage, lactobacillus bulgaricus and streptococcus thermophilus serve as fermentation strains, the fermentation temperature is 40 DEG C, and the fermentation time is 2 hours; the inoculum size of lactobacillus reuteri is 2%, the additive amount of a linoleic acid emulsion is 4.5%, the fermentation temperature is 37 DEG C, and the fermentation time is 4 hours; the content of CLA in the yogurt is measured as 1.32-5.78mg / ml. The technique provided by the invention has the advantages that the process is simple and convenient and the cost is saved, the content of CLA isomers in the yogurt is increased obviously, the yogurt tastes mellow, fine and smooth, and broad prospects are brought for industrial production.

Description

technical field [0001] The invention relates to the field of biological food, and uses a two-stage fermentation method to prepare yoghurt rich in conjugated linoleic acid. Background technique [0002] Yogurt is a kind of milk product that uses milk as raw material, adds beneficial bacteria (starter) to milk after pasteurization, after fermentation, and then cools and fills. At present, most yogurt products on the market are solidified, stirred and fruity with various fruit juices and jams. Yogurt not only retains all the advantages of milk, but also develops its strengths and circumvents its weaknesses in some aspects through processing, becoming a nutritional and health product more suitable for human beings. [0003] Conjugated linoleic acid (CLA) is a general term for a series of octadecadienoic acids containing conjugated double bonds and having positional and conformational isomers. It is an isomer of the essential fatty acid-linoleic acid (LA), and CLA There are man...

AI Technical Summary

Problems solved by technology

At present, the industry is mainly synthesized by chemical method, and the conversion rate is high, but the composition of isomers in the product is complex, and because the synthesis process is carried out under high temperature and pressure, the energy consumption is high, the risk factor is large, the environment is polluted, and the cost of the enterprise is increased, which limits the Its application in the food industry, pharmaceutical industry