Admassu, Shimelis(PhD)Bekele, Meseret2018-07-172023-11-102018-07-172023-11-102011-06http://etd.aau.edu.et/handle/12345678/8905This research paper aimed mainly at studying the effect of fermentation on QPM-soybean blends with respect to the nutritional quality, antinutrient, proximate & micronutrient compositions, functional & physico-chemical properties, microbiological & sensory analysis. Seed varieties of QPM & soybean (BHQPY-545 & Afgat) were collected from Bako & Hawassa Agricultural Research Centres respectively. After sample preparation, the flour was formulated with QPM to soybean blend ratio of 82:18 using material balance method (protein-carbohydrate ratio). QPMsoybean blend flours were fermented for 24 & 48h by natural & controlled fermentations. Both unfermented and fermented samples were subjected to the analysis. The proximate analysis results before & after fermentation in (%) were 14.72, 17.43 for crude protein; 8.42, 10.2 for crude fat; 7.33, 4.49 for crude fiber; 66.63, 66.90 for total carbohydrates and 400.81Kcal./100g, 412.67Kcal./100g for calorific value. Significant differences (P<0.05) were observed between unfermented & fermented blends in proximate compositions, with specific increment of 15.5% for protein & 3% calorific value. Results of antinutrient content (tannin & phytate) in (mg/100g) were 21.95, BDL & 249.20, 155.75 with notable reduction. Micronutrient increment in (mg/100g) for P, Fe & Zn was 32.57 to 61.9; 3.98 to 7.20 & 2.61 to 4.21 respectively. Fermentation significantly (p<0.05) decreased the antinutrients which resulted in a significant (p<0.05) increase in micronutrients. Fermentation had a significant (p<0.05) increasing effect on pH, dispercebility and oil absorption whereas; decreasing effect on titratable acidity, viscosity; bulk density & water absorption. Microbiological result showed significant (p<0.05) reduction or elimination of undesirable coliform count & increment of LAB with increasing fermentation time. Fermentation process significantly (p<0.05) affected the product performance analysis. Therefore, gruel prepared from the fermented blend flour at 24h of fermentation and <250μm particle size was acceptable with higher scores of 7.80 for appearance, 7.54 for odor, 8.10 for taste, and 8.50 for overall acceptability, which is not significantly (p>0.05) different from the control. According to the result of the study, both types of fermentation comparably reduced or eliminated antinutrients and improved the nutritional quality of the weaning blend with preference for natural fermentation, which is inexpensive processing method that consumers especially low & medium income families can easily afford good quality product. Key words: Antinutrient, effect, fermentation, micronutrient, natural fermentation, proximate composition, QPM, soybean, Weaning food.enAntinutrientEffectFermentationMicronutrientNatural fermentationProximate compositionQPMSoybeanWeaning foodThesis