Development and Sensory Evaluation of Gluten-Free Rice Bread Enriched with Soy Flour

Abstract

Background: Gluten-free diets are critical for individuals with celiac disease or gluten intolerance. However, most gluten-free breads often lack desirable sensory and nutritional qualities due to the absence of gluten. Enriching rice-based bread with soy flour presents a promising approach to improve its functional and sensory properties. Aim: This study aimed to develop gluten-free rice bread enriched with soy flour and evaluate its sensory attributes using hedonic tests, Quantitative Descriptive Analysis (QDA), Principal Component Analysis (PCA), and preference mapping, in order to identify formulations acceptable to consumers and nutritionally improved. Methods: Four bread formulations were prepared: Sample A (100% rice flour), Sample B (95:5 rice-to-soy flour), Sample C (90:10 rice-to-soy flour), and Sample D (100% wheat, as control). Sensory evaluation was conducted using a 7-point scale by panelists. Data were analyzed using ANOVA (p < 0.05), PCA biplot, and preference mapping to explore patterns in sensory preferences. Results: Hedonic evaluation showed that Sample D (wheat bread) had the highest overall acceptability (6.44 ± 0.77), while Sample C was the most preferred among gluten-free samples (5.30 ± 1.39), driven by improved taste, aroma, and texture. QDA confirmed similar trends, with Sample C receiving significantly better scores for key sensory attributes compared to other rice-based variants. PCA revealed that the first two principal components explained 97% of the total variation, clearly separating the samples by their sensory characteristics. Preference mapping identified Sample C and D as the most favored, correlating closely with taste and aroma. These findings demonstrate the positive sensory impact of soy flour at 10% substitution. Conclusion and Recommendations: Incorporating 10% soy flour into rice bread significantly improves sensory appeal, making it a viable gluten-free alternative with enhanced nutritional value due to soy’s protein and other functional food properties. Future research should focus on optimizing textural characteristics using natural improvers and validating consumer acceptance across wider populations. Education on soy’s health benefits could boost market penetration of such gluten-free formulations.