Physical and Functional Properties of Trifoliate Yam Flours as Affected by Harvesting Periods and Pre-treatment Methods

Abstract

The physical and functional properties of trifoliate yam flours processed using different pre-treated methods at varying .M.B. 301 Iree, Osun State, Nigeria harvesting periods were examined. The flours were subjected to physical (bulk density) and functional (water absorption, solubility and swelling power) analyses. The bulk density values for the trifoliate flours ranged from 0.54-1.03 g/cm3 . The parboiled flours had higher bulk densities in both cultivars of trifoliate yam flour. The parboiled white trifoliate yam flour harvested at 10 months had higher water absorption capacity (4.52 ml H2 O/g) and was significantly different (p>0.05) from other flours harvested at other periods. Soaked (60°C) flours harvested at 11 months had the least solubility (3.49%) while the parboiled trifoliate yam flour had higher solubility. At 60-80°C, parboiled flours had higher swelling power values than the other flours while at 90°C, the raw flours harvested at 7 and 9 months had higher values which was significantly different (p<0.05) from other flour samples. The physical and functional properties of trifoliate yam flours were more dependent on the pre-treatment methods rather than the harvesting periods.