The aim of this thesis was to explore the properties of a novel food protein and a novel processing technology for the development of high-quality protein foods. For this, quinoa was chosen as an alternative protein source and high pressure – high temperature (HPHT) processing was chosen as a novel processing technology. The findings of this thesis show that quinoa protein obtained can be used to prepare different types of food with optimised digestibility, depending on extraction and temperature conditions. A more sustainable and economic method for obtaining quinoa protein was developed, which makes it possible to use considerably less water compared to the conventional method. HPHT processing was found to potentially improve the quality of protein-sugar containing foods, for which browning and high viscosities are undesired, such as high-protein beverages. Therefore, quinoa protein and HPHT processing are promising to be used to develop high-quality protein foods.