Dual-process of starch modification: Combining ozone and dry heating treatments to modify cassava starch structure and functionality.

This work evaluated for the first time the effect of dual modification of cassava starch by using ozone (O 3) and dry heating treatment (DHT). The dual modification was capable to promote fissures on the surface of the starch granule (DHT + O 3), affected the starch amorphous domains, presented greater degree of starch oxidation (DHT + O 3) and different profiles of starch molecular size distribution. These modifications resulted in starches with different properties. Moreover, the sequence of treatments was decisive for the hydrogel properties: while DHT + O 3 resulted in formation of stronger gels, O 3 + DHT resulted in weaker gels. In conclusion, this proposed dual modification was capable to produce specific modified starch when compared with the isolated treatments, also expanding the potential of cassava starch applications. Unlabelled Image • Ozone (O 3) and dry heating (DHT) treatments were combined for starch modification. • Both structure and properties were evaluated. • Each process and combination differently changed the starch amorphous domain. • The sequence of the combined treatments influenced the starch properties. • DHT + O 3 treatment presented stronger gel, while O 3 + DHT had a poor gel formation. [ABSTRACT FROM AUTHOR]