Quinoa (Chenopodium Quinoa Willd.), a South American grain, has great potential for innovation and development of improved food products because of its protein content and nutritional benefits. The study aimed to develop an instant-mix beverage based on fermented quinoa with reduced phytate content and viable lactic bacteria. Two different lactic fermentation processes were designed known as Fermentation type 1 (F1) and Fermentation type 2 (F2) using Lactobacillus plantarum 299v® to obtain fermented quinoa flour. In F1, roasted quinoa grains were fermented for 9 h whereas raw quinoa grains were fermented for 6 h in F2 followed by drying, roasting and fermenting again for 3 h. Phytate reduction, Lactobacillus growth, acidity, protein content, and estimated mineral absorption were evaluated along with organoleptic acceptability of the product. The fermented quinoa samples (frozen at −20 °C and −80 °C) were freeze-dried for the development of instant powder mix beverage with 3 different fruit flavours. Phytate was significantly reduced (p < 0.05) in 61.8% and 64.4% in F1 and F2 respectively, which increased the estimated mineral absorption (Phy:Fe, 5.5 and 5.3); (Phy:Zn, 9.3 and 8.8) in both fermentations. High microbial viability was obtained in the fermented freeze-dried samples. The developed instant-mix of pineapple-orange flavour with 5% of fermented quinoa flour showed highest acceptability among all flavours during the sensory evaluation. Thus, fermentation is an effective way to improve nutritional and sensorial properties of quinoa. The developed instant-mix beverage with fermented quinoa had reduced phytate content, high probiotic count and better sensorial characteristics than a commercial product.
