QUALITY PARAMETERS AND GLYCEMIC INDEX OF BLENDS OF UNRIPE PLANTAIN, WHEAT BRAN AND SOY-PROTEIN CONCENTRATE AND DOUGH MEALS

Abstract

Over the years, there has been lots of research focused on the improvement of protein and fibre quality of food products due to the vast increase in malnutrition. Unripe plantain as a source of carbohydrate is consumed as a popular staple food in Nigeria. This study, therefore, aimed at enriching plantain flour with wheat bran which is a good source of fibre and soy concentrate that is also a very good source of protein. The plantain-soy-wheat bran mixes were prepared from green matured plantain, soy concentrates and wheat bran. Substituted plantain flour with wheat bran and soy concentrate at varying proportions were optimized using optimal mixture design of response surface methodology, which produced sixteen experimental runs. Five best composite flour blends of the plantain, wheat bran and soy protein concentrate were selected based on % protein and fibre contents after proximate composition determination (74.4:5.58:20(A), 78:6.3:15.8 (B), 70:10:20 (C), 75:10:15 (G), 71.8:8.17:20 (I)). A 100% unripe plantain flour was used as control. The physico-chemical, pasting, mineral, and dietary fibre properties of the selected blends were carried out. Reconstituted thick paste dough meal prepared from all the selected flour blends and control were evaluated for proximate composition, color profile, phytochemical, anti oxidant, consumer acceptability. Glycemic index of the enriched dough meal samples were determined by checking effect of the dough meals on the glucose level of 21 white albino rats. The blood glucose response at 30, 60, 90, 120 and 180 min was assessed for each rats of the different six groups. The proximate composition of the flour blends showed an increase of about 3.3% in the control (CS) to 25% crude protein content. The crude fibre content ranged from 3.32% in control CS to 16.8%, moisture content ranged from 6.78% to 8.76%, crude fat