Biodiversity of lactic acid bacteria isolated from spontaneously fermented amaranth and quinoa sourdoughs

RUIZ RODRIGUEZ L; SAAVEDRA L; FONTANA C; VERA PINGITORE E; ROLLAN G; PIER S.COCCONCELLI; VIGNOLO G; HEBERT EM

Istambul

Simposio; 23rd International ICFMH Symposium; 2012

ICFMH

,Domesticated by pre-Hispanic cultures, quinoa (Chenopodium quinoa) and amaranth(Amaranthus caudatus) crops have been used for feeding of the Andean population since atleast 3000 years. These ancestrally grown grains have recently attracted consumer´s attentiondue to their high protein content, nutritional value and gluten-free characteristics.Spontaneously fermented sourdoughs prepared from commercial amaranth (Sturla®) as wellas natural (Real Hornillos) and commercial (Yin Yang®) quinoa flours were analyzed fortheir lactic acid bacteria (LAB) diversity. The doughs were prepared over 10 day-period withdaily back-slopping (10 %) at a laboratory scale at 30°C. Samples were withdrawn daily atrefreshment steps; the dough pH-values and cell counts (CFU/g) as well as the identificationof LAB were evaluated by bacteriological culture together with genotypic identificationmethods. The pH value decreased from 6.1±0.3 to 4.2 ± 0.2 after 2 days of incubation andremained approximately constant until the end of the fermentation period. The LAB cellcounts in the sourdough samples ranged from 2.0±0.5 to 8.3±0.5 log CFU/g during the wholefermentation period. The analyses of the microbial diversity of the sourdoughs showed thatamaranth sourdough contained Enterococcus mundtii, Enterococcus casseliflavus,Lactobacillus rhamnosus, Pediococcus pentosaceus and Lactobacillus plantarum. TheEnterococcus strains were isolated in the dough at day 0 (without fermentation) while L.plantarum was the dominating species from day 2 to 10. The quinoa (Yin Yang®) sourdoughwas colonized by E. casseliflavus, Leuconostoc mesenteroides subsp. mesenteroides,Lactobacillus brevis, L. rhamnosus and L. plantarum while in addition to the aforementionedspecies, E. mundtii, Lactococcus lactis subsp. lactis and Leuconostoc citreum were alsopresent in Real Hornillos quinoa sourdough. This is the first study to report the isolation andcharacterization of LAB species from spontaneously fermented Andean amaranth and quinoa.Further studies are needed to evaluate the LAB isolates in view to be used as sourdoughstarter cultures.