Influence of final baking technologies in partially baked frozen gluten-free bread quality.

The effect of final baking in convection oven (FBC), microwave oven (FBM), and microwave oven with susceptor packaging material (FBMS) on partially baked (PB) frozen gluten-free bread characteristics was investigated. Specific volume and crust color of loaves were measured at day 0. Bread moisture, water activity, and crumb and crust texture (at 15, 45, and 90 min after baking) were analyzed at day 0 and after 28 d of frozen storage (-18 °C). Volatile compounds from breads baked in convection oven or microwave oven with susceptor packaging material were also evaluated. Bread finally baked in convection oven or in microwave oven with susceptor packaging increased crust browning. Crumb and roll hardness increased with time after final baking (measured at 15, 45, 90 min) and after 28 d of frozen storage. Bread finally baked in microwave oven was the hardest, due to high water losses. At day 0, bread finally baked in convection oven had softer crumb than bread finally baked in microwave oven with susceptor packaging but, after 28 d of frozen storage, there were no differences between them. Moreover, FBC and FBMS rendered gluten-free breads that could not be distinguished in a triangular test and had the same volatile compounds profile. In conclusion, FBMS could be an alternative to FBC.

Effect of tiger nut-derived products in gluten-free batter and bread.

Tiger nut is a tuber used to produce tiger nut milk that yields a high quantity of solid waste, which can be dried and used as fiber source. The objective of this paper was to evaluate the quality of gluten-free bread formulated with different tiger nut-derived products in order to substitute soya flour (which is an allergen ingredient) and, at the same time, increase the use of tiger nut-derived products. Four gluten-free formulations based on corn starch and containing tiger nut milk, tiger nut milk by-product, tiger nut flour, or soya flour (as reference formulation) were studied. Tiger nut milk increased G' of gluten-free batter and rendered breads with the softest crumb (502.46 g ± 102.05), the highest loaf-specific volume (3.35 cm(3)/g ± 0.25), and it was mostly preferred by consumers (61.02%). Breads elaborated with tiger nut flour had similar characteristics than soya flour breads (except in color and crumb structure). The addition of tiger nut milk by-product resulted in a hard (1047.64 g ± 145.74) and dark (L(*) = 70.02 ± 3.38) crumb bread, which was the least preferred by consumers. Results showed that tiger nut is a promising ingredient to formulate gluten-free baked products.