The main objective of this study was to optimize the fermentation conditions of goji and to analyze the sugar, organic acid, amino acid, and flavor compounds before and after the fermentation of goji. Based on the single‐factor experiment, orthogonal array design and the range analysis, the optimized conditions for fermented goji were 30% raw material concentration, 28 h fermentation time and 0.05% inoculum size, respectively. Under optimal conditions, the biomass of Lactiplantibacillus plantarum NCU137 and sensory score of fermented goji reached to 8.84 ± 0.05 log CFU/g and 81.3 ± 1.5, respectively. After fermentation, the content of malate, succinic acid, and lactate increased, while the content of pyruvate, glucose, fructose, and the overall free amino acid decreased. After fermentation, volatile components except for the phenols and acids are declining. This study would provide theoretical basis and experimental data for the industrialization of Lycium barbarum fermentation.
Novelty impact statement
After Lactiplantibacillus plantarum NCU137 fermentation, the contents of organic acids and total acidity acid in fermented goji significantly increased, which could inhibit microbiological spoilage and growth. Moreover, we get a delicious fermented goji juice through the optimization of fermentation conditions. Therefore, the data obtained in this study provides a better understanding of the effects of raw material content, fermentation time, and inoculum size on the quality of fermented goji, which would be very beneficial for the production of high‐quality fermented goji for subsequent consumption.