Abstract:
Incorporating D.praehensilisinto cassava gari could improve thenutritional profileof cassava-yam composite gari. This study investigatedthe effects of yam quantity (X1), fermentation duration (X2), and roasting temperature (X3) on the physico-nutritional qualities of the cassava-yam composite gari and then evaluatedthe effects of packaging materials and storage conditions on the quality attributes.Athree-factor three-level response surface methodology (RSM) was used for the optimisationstudy while the storage study was done using 32×3 factorial.Interestingly, an increase inyam quantity, fermentation duration, and roasting temperatureresulted in a significant increase in the beta-carotene content.The iron and zinc contentsof the cassava-yam composite gari increasedsignificantly whenthe yam quantitywasincreased. Swelling capacity was reduced by yam quantityhowever, the roasting temperatureincreased the swelling capacitysignificantly to 3.40.Yam quantityreduced theflavour, taste, texture, and overall acceptabilitybut waspositively influenced by fermentation. Roasting temperature affected the brownnessmore than the other processing variables. All sensory attributes, L*,beta carotene, and swelling capacitywere reducedunder all packaging materials and storage conditions. However, the reduction was significantly higher under polyethylene (PE) packaging material at 32.22 ± 3.34⁰C. The brownness (a*) increased in PE, polyethylene/polyethylene terephthalate (PE/PET), and polyethylene/polyethylene terephthalate/aluminium (PE/PET/AL)packaging materials but the increase was significantly higher in PE under open market (OM) condition at 32.22 ± 3.34⁰C.PE/PET and PE/PET/AL provided a strong barrier propertyagainst temperature (32.22 ± 3.34⁰C). Considering fixed and variable costs, producing a tonne of the optimised gari yielded profit.
