Calafate (Berberis microphylla) juice fermentation by autochthonous fruit and flower lactic acid bacteria isolates

BRENDA SEDE LUCENA; OMAR F. ORDOÑEZ; LUC DE VUYST; FERNANDA MOZZI; MICAELA PESCUMA

Egmond aan Zee

Simposio; 13th LAB Symposium; 2021

Calafate is an endemic plant from Patagonia thatis used since pre-historic times as food and medicine.Lactic acid bacteria (LAB) improve the storage and sensory quality of fruits. LABfrom Calafate fruits and flowers were isolated to be used as starter culturesfor juice fermentation. Fruits and flowers (Esquel, Chubut, Argentina) were macerated,diluted, and plated on MRS agar with cycloheximide (0.1 g/L). Potential LABwere subjected to RAPD-PCR and 16S rRNA gene sequencing for identification. TwoCalafate juice concentrations (15 and 30 %, v/v; 4 and 8 °Brix, respectively)adjusted to pH 5.1 were used. Microbial growth, pH, and phenolic concentrationswere determined after 24 h of incubation at 30 °C. Two and eight RAPD-biotypeswere detected among the fruit and flower LAB isolates, which corresponded to Lacticaseibacillus sp. and Leuconostoc sp., respectively. L. paracasei WB4 and Lc. citreum TC5 grew (1.4-2.8 logcfu/ml) and decreased pH (1.03-0.70 and 0.92-0.88, respectively), with both Calafatejuice concentrations. The high initial phenolic content (1.46-2.64 g GAE/L) in15 and 30 % juices decreased (9.4-10.9 and 20.6-22.3%, respectively) afterfermentation with both LAB strains. This is the first report on LAB isolatesfrom Calafate able to grow in high phenolic-containing fruits.