Comparison of nutrients and microbial density in goji berry juice during lactic acid fermentation using four lactic acid bacteria strains

摘要

To study the effect of lactic acid fermentation of goji berry juice on the antioxidantactivity and metabolism of sugars, organic acids, and amino acids, four different lacticacid bacteria were adopted in the fermentation and metabolites were analyzed.Results showed that all strains could grow well in goji berry juice and Lactobacillusbrevis showed much better growth rate. Malic acid, was significantly metabolized byall bacteria. Lactic acid was detected as the most produced acidic metabolite duringthe fermentation, especially by Lactobacillus plantarum. In addition, inoculated withlactic acid bacteria could increase the content of biogenic amines and decrease thecontent of amino acids. Moreover, a significant increase of total polyphenol and antioxidantactivity was found by inoculation with Lactobacillus acidophilus. Fermentationcould lead to the goji berry juice more darkness, redness, yellowness, and saturation,which was more evident in L. acidophilus and L. plantarum fermented samples.Practical applicationsGoji (Lycium barbarum) has been cultivated in large scale with more than 200,000 tannual yield of its berry in China. However, a small percentage of them has been usedfor industrial processing. In the present study, four strains of lactic acid bacteria wereused to ferment goji berry juice, and their growth and effect on the quality of thejuice were compared. Our results will provide useful information for the developmentof new goji berry processing products.