Characterization of the Microbiota of Quinoa and Amaranth Grains, and Production of Fermented Quinoa Milk

The development and consumption of functional food are increasing. To meet such an increasing demand, vegetable milk extracted from quinoa and fermented with lactic acid bacteria can offer an excellent alternative to fermented dairy milk which has a high nutritive value and is free from lactose, gluten and cholesterol. This research aims at: (a) isolating and identifying the autochthonous microbiota from amaranth and quinoa grains, and (b) developing a method for producing fermented quinoa milk, using as a matrix red and white quinoa grains by lactic acid bacteria originated from quinoa grain. To meet the first objective, one amaranth and five types of quinoa grain were used for isolation of bacteria. And for the second objective, red and white quinoa milk was used for fermentation. The bacteria tested for inducing the fermentation on the quinoa milk were: Lactobacillus plantarum 299v, Lactobacillus plantarum, Lactobacillus pentosus and Pediococcus pentosaceous. Fermented quinoa milk was stored for 28 days at 4 oC to monitor pH, acidity and survival of lactic acid bacteria. Lactic acid bacteria, L. plantarum, L. penthosus, E. gallinarum, E. casseliflavus from amaranth, and E. mundtii from both amaranth and black quinoa grain were isolated. There was no statistically significant difference in the production of lactic acid between aerobic and anaerobic fermentation of quinoa milk during fermentation and storage. Decreased pH and increased acidity was observed in all types of fermented quinoa milk. During 28 days of storage, the highest (over 99 percent) survival rate was found in fermented red quinoa milk by L. plantarum. The findings confirmed that the lactic acid bacteria can be isolated from amaranth and quinoa grains. The study also strongly confirms that it is possible to develop fermented quinoa milk by lactic acid bacteria.