Effect of Chemical Pretreatments on the Physico-Chemical and Sensory Attributes of Sweet Potato-Gari
Abstract
The effect of addition of sodium metabisulphite, NaS2O5 (2.5 and 0.5%) and lime juice (2.5 and 0.5%) on the quality of sweet potato-gari was investigated. Untreated sweet potato-gari and cassava-gari served as control. Moisture content of cassava-gari and sweet potato-gari ranged between 7.95 and 8.80% db. The pH and TTA values of sweet potato-gari were 5.8 to 6.0 and 0.94 to 0.99, respectively, while cassava-gari had pH 4.42 and Total Titratable A of 1.11% lactic acid. Swelling capacity showed that sweet potato-gari pretreated with 2.5% NaS2O5 had the lowest value of 252% compared to those pretreated with 0 .5% lime with highest value of 301% while cassava-gari recorded 430%. Sample from 2.5% NaS2O5 treatment had the highest average particle size index followed by sample treated with 2.5% lime having the lowest. There were significant differences (P<0.05) in the sensory attributes of sweet potato-gari and cassava-gari also in the treated sweet potato-gari and untreated sweet potato-gari samples. The gari samples containing 2.5% lime juice and 0.5% Sodium metabisulphite were comparable to colour of cassava-gari.
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