Production Design of Modified Cassava Starch by Biotechnology

Abstract Sour cassava starch is a product obtained after the natural fermentation of cassava starch and is used in the baking industry. It is prepared with native microorganisms and their amylolytic activity. Although this process depends on empirical knowledge, it generally does not have good manufacturing practices. This study was initiated from the selection of Bacillus , which is naturally present in and used as a modifier of starch, as the native microorganism with amylolytic activity. Time, aeration and starch concentrations were established to obtain a starter culture. Then, a culture medium for starch modification and microbial growth in 18 days was formulated. The α-amylase activity of B. amyloliquefaciens increased until a maximum value of 62 mmol/min.mL at day 16. Pasting curves showed a maximum decrease in viscosity at day 12 for B. amyloliquefaciens , reaching 177 Brabender units (BU), and at day 16 for B. vallismortis , reaching 167 BU. Based on these conditions, a new process was proposed to obtain modified cassava starch using microorganisms. This process may be used for industrialisation to obtain higher production yields for starch modified by biotechnological methods. To the best of our knowledge, this is the first method proposed in America continent for the production of sour cassava starch using microorganisms; this method is scalable and suitable as a standardised process. Graphical Abstract