Quality Analysis of Soy Bread and Its Effects on Glycemic Index

Introduction: Low glycemic index foods have been associated with several health benefits. Similarly, soy-based food products have an increasing demand in the market due to its high nutritional value. Objectives: The study was conducted to produce high-quality protein-enriched bread with low glycemic index (GI) value. Methods: The fortification of bread was done with soy flour in our study. The proximate analysis, sensory evaluation and the GI value of the bread sample were determined. Result: The crude protein, crude fiber, fat and ash content of the bread progressively increased with the addition of soy flour where 20% soy bread having the highest values as 14.5%, 0.7%, 5% and 2.1%, respectively and control bread having lowest values as 9.2%, 0.2%, 1.8%, and 1.7%, respectively. The sensory evaluation of bread showed no significant differences in crust, shape, internal texture, appearance and general acceptance where the aroma and the taste of bread samples were significantly different from the control bread. Taste of bread had a low score of 5.81 at 20% soy substitution bread and highly differed with control bread (p<0.01). The GI values were significantly lowered by 15% (p<0.05) and 20% (p<0.01) soy sample bread. The average GI value of Control, 10%, 15% and 20% soy substitution bread were 60.4, 49.98, 44.37 and 39.19 respectively. Glycemic Index decreased from 18% to 35% with the incorporation of soy flour (10% to 20%) in the bread sample. Conclusion: The soy flour treated breads were found nutritionally superior compared to soy untreated food.