Physicochemical characterization of special cassava starches and their application for bio-ethanol production through no-cook technology at very high gravity

• Published in: Industrial crops and products 2024-11, Vol.219, p.119095, Article 119095
• Main Authors: Moreno Alzate, Jhon Larry, Tran, Thierry, Ceballos, Hernan, Nguyen, Chinh-Nghia, Nguyen, Tien Cuong, Zhang, Xiaofei, Newby, Jonathan, Dufour, Dominique, Chu-Ky, Son
• Format: Article
• Language: English
• Subjects: amylose; Amylose-free starch; cassava; cassava starch; Colombia; ethanol; ethanol production; feed additives; fermentation; genotype; liquefaction; mutants; physicochemical properties; resistant starch; saccharification; Simultaneous liquefaction saccharification and fermentation (SLSF); Small granule starch; temperature; Very high gravity (VHG)
• ISSN: 0926-6690
• DOI: 10.1016/j.indcrop.2024.119095

Various cassava genotypes were developed with distinct starch characteristics, including amylose-free and small-granule mutations. Despite these unique traits, the ethanol production potential of these starches has not been explored. Cassava starch plays a crucial role in ethanol production, particularly in tropical countries like Colombia. This study aimed to assess the physicochemical properties of different cassava starches (including the amylose-free and small granule mutations), and to evaluate their potential for ethanol production using the Simultaneous Liquefaction, Saccharification, and Fermentation process under very high gravity (SLSF-VHG) and no-cooking conditions. Comparative analysis revealed that two double mutant starches and small-granule starch (GM4694–1) exhibited lower resistant starch content than those from wild-type and amylose-free cassava, making them more susceptible to enzymatic breakdown. The amylose content for GM4694–1 and wild-type cassava was 21.9 and 16.1 %, respectively, while the remaining samples were amylose-free. In the SLSF-VHG process, GM4694–1 demonstrated a significant ethanol yield, surpassing 16 % v/v, equivalent to 80 % of the theoretical ethanol yield within 90 hours. This suggests that the GM4694–1 genotype has the potential to produce ethanol efficiently at a temperature of 30°C. Furthermore, the solid residue obtained after the SLSF-VHG process could serve as a high-quality feed additive. This study enhances our understanding of the properties of special cassava starches and their correlation with ethanol production. [Display omitted] •Characterization of physicochemical properties of special cassava starches from the CIAT cassava breeding program.•Evaluation of ethanol production capacity by no-cook SLSF process at very high gravity.•The process using small-granule starch achieved a high 17 % v/v ethanol after 90 h, compared to 160 h for other starches.•Starch properties can predict the level of ethanol conversion.