Plant proteins are attracting much interest as an ingredient in the food sector due to their functional properties. These products are, in fact, widely studied to improve the quality of food products and to develop new types of bio packaging. This paper aims to study and investigate the potential of adding vegetable proteins (specifically soybean and sunflower) to improve the physicochemical stability of hazelnut pastes which are widely used in the food sector as a product itself or as an ingredient for many products, such as pastry, confectionery, and ice-cream. To investigate the effect of protein incorporation, hazelnut paste samples were stored under temperature accelerated conditions to simulate at least 10 months of shelf-life under normal storage conditions, and periodically analyzed for water activity, lipid oxidation, tocopherols content and oil separation. The study showed promising results for both added proteins, especially in terms of the physical stabilization of the product.