Identification of Lactic Acid Bacteria in Fermented Cornichon Pickles Produced with Acid Whey and Vinegar

Abstract

The purpose of this study is to isolate, identify and compare lactic acid bacteria responsible for fermentation from pickles produced with vinegar and acid whey (AW). For this reason, fermented cornichon pickles were produced by using AW and vinegar as brine media. Colonies with different morphologies were selected and isolated at the 0, 7, 14, 21, 35, 49, 77 and 105th days of fermentation. A total of 139 isolates were obtained. Salt, acidity and pH values of brine and cornichon were followed on each analysis day. Growth and gas formation from glucose of isolates at different temperatures (10, 45, and 50 oC), salt concentrations (2, 4.5, and 10% (w/w)), different pH values (3, 4.5, and 9.6), were analyzed. Eight isolates were determined as heterofermentative according to their ability to produce CO2 from glucose. The isolates were observed to show the highest growth at 10 oC, and a very few isolates developed at 45 oC and 50 oC. No isolates were able to grow at pH 9.6, 25 of the isolates were able to grow at pH 4, and only 4 isolates were able to grow at pH 3. Only one isolate was able to show resistance to 10% salt concentration. Almost all isolates grew at 2% and 6.5% salt concentrations. 48 selected isolates were identified with API 50 CHL. 19 isolates were determined as Lactobacillus pentosus (8 vinegar, 11 AW) and 29 isolates as Lactobacillus plantarum (16 vinegar, 13 AW). As a result, L. plantarum and L. pentosus species were the dominant bacteria for cornichon pickles produced with AW and vinegar. Microbial flora in the pickles produced with two different brines were similar. The results show that AW can be successfully used for pickle production.