Ability of commercially available lactobacillus strains as starter in brining and debittering of table olives

Abstract

The adaptation to brining conditions of 20 strains of Lactobacilli were tested. At 6% salt all strains reduced the pH to 4 in 72 h. At higher salt concentration, only some of the strains showed this ability. The ability to synthesise lactic acid was tested at different salt concentrations. Lactic acid was quantified by HPLC analyses and at halophilic conditions six strains showed good ability. The glucosidic activity tested on a synthetic compound (p-nitrophenyl-β-D-glucopyranoside) screened the best Lactobacillus strains (20205 DSMZ, 20314 DSMZ and 104442 CIP). The ability to hydrolyse the oleuropein molecule was tested and all of the strains selected showed good activity at low salt concentration and low oleuropein content in the medium. This ability decreased drastically when the salt and oleuropein content were higher. The best strain was the 20205 DSMZ, which at low salt concentration hydrolysed more than 95% of oleuropein in 120 h.