The invention relates to a preparation method of 
Nisin double layer microcapsule suitable for high temperature baking food. The preparation method of the 
Nisin double layer microcapsule suitable for the high temperature baking food includes: mixing 
Nisin and 
chitosan according to a 
mass ratio which ranges from 1:1 to 1:10 so as to obtain a solution, and then regulating PH (potential of 
hydrogen) of the solution to 2.5-7.5, adding Tween80 and PEG into the solution so as to emulsify the solution and obtain 
emulsion, and then slowly dripping a 
sodium tripolyphosphate solution into the 
emulsion so as to prepare 
chitosan microcapsule with the Nisin embedded under stirring functions, 
processing the Nisin 
chitosan microcapsule, and finally mixing and stirring the Nisin chitosan microcapsule and 
xanthan gum so as to obtain the Nisin double layer microcapsule, wherein a 
mass ratio between the 
sodium tripolyphosphate solution and the chitosan is 3:1-10:1. Compared with a 
free state Nisin product, the encapsulated Nisin product prepared by using the preparation method of the Nisin double layer microcapsule suitable for the high temperature baking food is strong in tolerance to PH, temperature and enzymes, can be processed along with food, and can not influence the 
fermentation process of fermented food, and high temperature and 
high pressure in 
processing can enable the Nisin double layer microcapsule to rapidly release the Nisin, and therefore influences of embedding wall materials on antibacterial effects of the Nisin are eliminated.