Abstract: In this experiment, the fermentation of blueberry pomace was optimized to improve the quality of fermented
products. The fermentation parameters inoculum quantity, temperature, initial pH and fermentation time were selected to
investigate their effects on yeast biomass and protease activity and to carry out the optimization experiments using onefactor-
at-a-time and orthogonal array methods. The optimal fermentation conditions were determined as follows: yeast
fermentation of blueberry pomace was conducted for 16 h at 30 ℃ with an inoculum size of 0.15% at an initial pH of 3.5,
and then the fermented mash was adjusted to pH 4.0 and inoculated with Lactobacillus casei at an inoculum size of 0.50%
for further fermentation for 24 h at 18–20 ℃. Concentration and vacuum freeze drying of the final product gave a powder
with an aroma and good quality.

Key words: blueberry pomace, ferment, fermentation, vacuum freezing drying