Using ground oyster mushroom and chia seeds for the fortification of wheat bread-Nelder–Mead simplex optimisation

Wheat bread was enriched with ground chia and ground oyster mushroom to improve its nutritional properties regarding protein and fibre content within the context of food fortification while maintaining a high specific volume and a soft crumb. A bread made from 100% wheat flour was used as reference. The Nelder–Mead simplex algorithm was used to determine the optimal proportions of chia and oyster mushroom substitution in the recipe. Bread quality was analysed and rated. Chia has a positive effect on the baking result due to its water-binding capacity, while mushrooms have a rather negative effect caused by the enzymes they contain. It was possible to replace 1.6% of wheat flour with ground oyster mushroom and 1.2% chia without any deviations from the control within 7 steps Furthermore, the partially substituted breads showed 3.8% lower contents of carbohydrates with a reduction of 4.1% of total sugar and higher contents of dietary fibre and protein, 22.7% and 2.3% respectively in comparison with the control sample. The wheat flour in bread can be replaced by chia flour and ground oyster mushrooms in small quantities without compromising the quality of the bread while improving some nutritional values.