Comparative analysis of plant-based high-protein ingredients and their impact on quality of high-protein bread

The orientation of consumers and industry towards plant-based foods on one hand and high-protein products on the other is persistently increasing. Bread, as a staple food, is a promising matrix for the incorporation of plant-based high-protein ingredients to combine both trends. This study aims to provide a better understanding of techno-functional changes and impacts of plant-proteins during bread production, which could advance the development of high-quality products with high levels of plant-protein. A selection of high-protein ingredients from wheat, maize, potato, carob, pea, lupin and faba bean were subjected to compositional analysis and applied in wheat bread formulations, replacing 15% of wheat flour. Their impact on dough properties (gluten-aggregation, pasting behaviour, rheology) as well as bread quality (volume, crumb structure, crumb hardness) was analysed. The high-protein ingredients were found to affect gluten-aggregation, pasting and bread characteristics. Results indicated a weakened gluten-network in doughs containing potato and pea protein. Also pasting behaviour was mostly affected by the potato protein suggesting a heat induced improvement of its baking performance. Good bread quality, represented by high specific volumes and low crumb hardness, was observed for gluten, zein and carob. Breads with pea, lupin and faba bean showed only slightly inferior quality characteristics.