Effects of the Type and Point of Inclusion of Soy-Melon-Protein Supplement on the Sensory Qualities of “Gari” Semolina

The effects of the type of enrichment and the stage of application of supplement on the sensory qualities of Soy-melon protein-enriched gari semolina were studied. Three protein supplements (Full fat, Defatted and Milk residue) were added to the gari meal before fermentation, after fermentation and after toasting. After toasting and cooling, the samples were subjected to sensory evaluation at weekly interval over a period of 32 weeks by 20 member sensory panel of the Federal University of Technology, Akure, Nigeria in order to determine its shelf life. The panel members were students and staff members who were used to the consumption and sensory evaluation of gari. They were instructed to evaluate differences in overall sensory quality between the control and other samples packaged in HDPE film and Woven sack and subjected to storage at 20, 30 and 40°C. A nine-point hedonic scoring system was used for the evaluation, where 1 = extremely disliked and 9 = extremely liked. Results obtained from other data on the flavor difference scores for each product were subjected to regression analysis based on the critical minimum panel mean score of 5.0 for shelf stability of the samples. The shelf lives for the samples at different storage conditions were determined from the slopes of the regression equations. Results showed that enrichment with soy-melon flour reduced the shelf life at a high temperature above 40°C from 148 weeks to 17 weeks. The shelf lives of samples packaged in HDPE were significantly higher than those packaged in woven sack. The shelf life was reduced significantly by increase in temperature which exhibited a negative correlation with the flavor scores.