Technological characteristics of inulin enriched gluten-free bread: Effect of acorn flour replacement and fermentation type

Textural, physicochemical, and sensory characteristics of rice-based gluten-free bread in the presence of acorn flour; inulin and different fermentation type (yeast starter fermentation [Y] or mixed fermentation based on sourdough [MF-SD]) were investigated. Acorn flour was added to replace rice flour at a proportion of 10, 30, and 50% W/W. Furthermore, the mixture flour was replaced by inulin as a functional prebiotic ingredient at 10% W/W. Considering results obtained at this study, using mixed fermentation based on sourdough and inulin at 10% W/W provide the structure able to restore gases through baking process at formulations containing acorn flour at 30% W/W (A(30)R(70)SL). The highest specific volume (1.47 +/- 0.04 cm(3) g(-1)) and the lowest hardness (40.97 +/- 0.87 N) are observed in A(30)R(70)SL which seems to be induced by its potential to form gel. Acorn flour substitution level at 50% W/W adversely influenced the technological characteristics of final product and its perception by the consumer. Acorn flour substitution up to 30% W/W is preferred by the consumer which is attributed to its potential role to improve the unpleasant pale color of rice-based gluten-free products. A negatively significant correlation has been observed between the color perception by the consumer and crumb lightness (r = -.493, p <= .05).

Automated summary

The study investigated the characteristics of rice-based gluten-free bread with the addition of acorn flour, inulin, and different fermentation types. It was found that using mixed fermentation based on sourdough and adding 10% inulin resulted in a structure capable of restoring gases during baking with 30% acorn flour. Consumers preferred acorn flour substitution up to 30% due to its potential to improve the color of the product.