Microbiological and chemical characteristics of tarubá, an indigenous beverage produced from solid cassava fermentation

• Tarubá is an indigenous beverage fermented by yeast and bacteria.
• LAB and Bacillus species were predominant during fermentation.
• The Torulaspora delbrueckii species was the dominant yeast during fermentation.
• Amylolytic, proteolytic and thermotolerance properties were found for some isolates.
• Isolates (T. delbrueckii, Pichia exigua, Bacillus spp.) are potential starter culture.

The aim of this work was to identify and characterize the microbiota present during fermentation and in the final beverage, tarubá, by culture-dependent and -independent methods. In addition, target chemical compounds (carbohydrates, organic acids, and ethanol) were evaluated. Lactic acid bacteria (LAB) and mesophilic bacteria were the predominant microorganisms. Among them, Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides, and Bacillus subtilis were frequently isolated and detected by DGGE analysis. Torulaspora delbrueckii was the dominant yeast species. Yeast isolates Pichia exigua, Candida rugosa, T. delbrueckii, Candida tropicalis, Pichia kudriavzevii, Wickerhamomyces anomalus, and Candida ethanolica and bacteria isolates Lb. plantarum, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus sp., and Chitinophaga terrae showed amylolytic activity. Only isolates of P. exigua and T. delbrueckii and all species of the genus Bacillus identified in this work exhibited proteolytic activity. All microbial isolates grew at 38 °C, and only the isolates belonging to Hanseniaspora uvarum species did not grow at 42 °C. These characteristics are important for further development of starter cultures; isolates of T. delbrueckii, P. exigua, and Bacillus species identified in this work displayed all of these properties and are potential strains for use as starter culture in cassava fermented food.