Abstract

Starches obtained from three varieties of cassava (Manihot palmata Muell), (4(2)1425 (V1), NR84104 (V2) and NR84293 (V3)) were fermented and chemically modified. The functional and pasting properties of the starches were investigated and the possible contributions of these properties to the explanations of the baking potentials of the starches. The hydrophilic nature of the starches was found to improve strongly after fermentation, while the hydrophobic tendency decreased. The fermented acetylated starches gave the highest value for the swelling index (SWI) and these values were significantly different (p ≤ 0.05) (with the exception of the acid-thinned starches). The pasting temperature for all the starches ranged from 71.9 to 77.6°C and the pasting time was higher in the fermented starches. The peak viscosity (PV) ranged from 151.58 to 317.75 RVU in V1, 154.08 to 249 RVU in V2 and 86 to 243.75 in V3. With the exception of unfermented acetylated starches (AcUFCS) all the modifications reduced the PV of the native starch. AcUFCS had the highest PV (317.75 RVU). Although, the different modification showed different effect on the sensory properties of the wheat/starch bread, highest score for the overall acceptability was associated with the unfermented acetylated starches.

Key words: Cassava, fermentation, modification, viscosity, specific volume.