Formation of γ-aminobutyric acid (GABA) during the natural lactic acid fermentation of cucumber

Abstract

This study investigated γ-aminobutyric acid (GABA) formation during natural lactic acid fermentation of cucumbers. Two lots of cucumbers were fermented or acidified in duplicate in 4 % sodium chloride (NaCl) brine and analyzed for GABA content over 6 months storage. GABA was present in fresh and acidified pickling cucumbers at 0.83 ± 0.16 mM and 0.56 ± 0.30 mM, respectively. Additional GABA was generated in fermented cucumbers (1.21 ± 0.35 mM) and remained stable over time and during further processing. Brine salt content (2 % - 6 %) affected GABA formation with greatest GABA formation in cucumber brined in 2 % NaCl (1.38 ± 0.31 mM). Commercially available, fermented cucumber pickles packed in their original fermentation brines contained more GABA (1.32 ± 0.25 mM) than acidified (0.46 ± 0.26 mM) or fermented, desalted and re-packed products (0.49 ± 0.32 mM). This work demonstrated that low-salt fermentation enhances GABA content in fermented cucumber products prepared for direct consumption.