HEBERT Elvira Maria
congresos y reuniones científicas
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.; COCCONCELLI, P.S.; VIGNOLO, G.; HEBERT, E.M.
Simposio; 23rd International ICFMH Symposium. Food Micro 2012; 2012
Domesticated by pre-Hispanic cultures, quinoa (Chenopodium quinoa) and amaranth (Amaranthus caudatus) crops have been used for feeding of the Andean population since at least 3000 years. These ancestrally grown grains have recently attracted consumer's attention due to their high protein content, nutritional value and gluten-free characteristics. Spontaneously fermented sourdoughs prepared from commercial amaranth (Sturla®) as well as natural (Real Hornillos) and commercial (Yin Yang®) quinoa flours were analyzed for their lactic acid bacteria (LAB) diversity. The doughs were prepared over 10 day-period with daily back-slopping (10 %) at a laboratory scale at 30°C. Samples were withdrawn daily at refreshment steps; the dough pH-values and cell counts (CFU/g) as well as the identification of LAB were evaluated by bacteriological culture together with genotypic identification methods. The pH value decreased from 6.1 ±0.3 to 4.2 ± 0.2 after 2 days of incubation and remained approximately constant until the end of the fermentation period. The LAB cell counts in the sourdough samples ranged from 2.0±0.5 to 8.3±0.5 log CFU/g during the whole fermentation period. The analyses of the microbial diversity of the sourdoughs showed that amaranth sourdough contained Enterococcus mundtii, Enterococcus casseliflavus, Lactobacillus rhamnosus, Pediococcus pentosaceus and Lactobacillus plantarum. The Enterococcus 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®) sourdough was colonized by E. casseliflavus, Leuconostoc mesenteroides subsp. mesenteroides, Lactobacillus brevis, L. rhamnosus and L. plantarum while in addition to the aforementioned species, E. mundtii, Lactococcus lactis subsp. lactis and Leuconostoc citreum were also present in Real Hornillos quinoa sourdough. This is the first study to report the isolation and characterization 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 sourdough starter cultures