Influence of solid-state fermentation on the functional characteristics of pearl millet starch: An innovative and cost-efficient approach to modify starch

Abstract

The current investigation aimed to assess how the fermentation process impacts pearl millet starch. Two distinct fungi, Rhizopus azygosporus and Aspergillus sojae, were employed to alter the structure of starch granules. Fermentation led to the creation of pores on the surface of the starch granules. A comparative examination of the fungal strains revealed that Aspergillus sojae fermentation resulted in the highest number of pores in pearl millet starch when compared to Rhizopus azygosporus. The particle size of the starch granules experienced a significant reduction following fermentation. Moreover, noticeable changes were observed in the amylose content, swelling capacity, and solubility of pearl millet starch. An increase in both the amylose content and solubility of pearl millet starch was noted, with values shifting from 14.27 % to 15.96 % and 17.37 % to 20.41 %, respectively. Additionally, the starch extracted from fermented pearl millet displayed a significant decrease in swelling power, decreasing from 15.53 g/g to 13.15 g/g. These findings affirm that solid-state fermentation holds promise as an innovative and cost-effective method for starch modification.

Keywords

• Starch
• Fermentation
• Amylose
• Swelling
• Solubility