Physicochemical Characteristics of “Gari” Semolina Enriched with Different Types of Soy-melon Supplements

Abstract

The effects of enrichment of “gari” semolina with three different types of soy-melon protein supplements during toasting of “gari” were studied. Three protein supplements (Full fat, Defatted and Milk residue) were toasted together separately with the grated, dewatered and sifted cassava mash after fermentation (soak-mix method). After toasting and cooling, the samples were subjected to physico-chemical analyses. Results showed that enrichment increased the protein, fat and ash contents, and the pH values, while the hydrocyanic acid content, titratable acidity reduced generally. Enrichment increased the protein content from 2.81% in the control gari to a range of 15.3% - 23.5% in the enriched samples. The fat increased from 3.24% to a range of 4.13% - 13.50%; while the ash content increased from 1.18% to a range of 1.96% to 3.47%. Hydrocyanic acid was significantly (P ≤ 0.05) reduced from 13.5mg/kg to a range of 6.70mg/kg -12.5mg/kg in the enriched products. The pH increased from 3.62 to a range of 4.86 - 5.25 while the acidity correspondingly reduced from 0,46 in the control gari to a minimum value of 0.36% lactic acid in the sample toasted together with defatted soy-melon meal. From the result it could be concluded that enrichment improved the nutrient quality of “gari” especially the protein, fat and ash contents. It also reduced the hydrocyanic acid content, thereby producing “gari” of higher quality and better safety. The acidity of the enriched samples was however reduced thus lowering the sourness of “gari”. This may be an advantage for people who are not used to the sour taste of “gari”. Of all the three soy-melon “gari” samples, the sample enriched with defatted supplement had been shown to have the highest protein and ash contents, the lowest crude fat and acidity than other enriched gari samples. It had also been shown to have better wettability, water holding capacity, and ability to disperse in water. It also had better swelling and reconstitution indices than “gari” enriched with full fat and milk residue supplements.