Identification and mitigation of allergens in alternative proteins and novel foods

This PhD work deals with the allergenicity of alternative protein sources and novel foods in response to the growing demand for sustainable and nutritious proteins. With a global prevalence of food allergies of 8-10%, there is a growing interest in alternative proteins, including legumes such as soybean, peanut and lupin, which are regulated as allergens in the EU, as well as other legumes that are not yet labelled, such as chickpeas, peas, beans and lentils, and newly approved foods such as insects, seaweed, and innovative plant-based ingredients. Assessing the allergenic potential of these ingredients is essential to protect individuals with food sensitivities. This PhD thesis aims to investigate and identify allergenic proteins in various vegetal and alternative protein sources and novel foods, by using a combined molecular approach and allergenicity studies. In particular, the study aims to: i) characterize novel proteins, identify new allergens, and study how they may cross-react with other known allergens; ii) evaluate enzymatic and physical modifications for modulating allergenic potential; iii) study IgE-binding under physiological conditions; iv) assess methods for the detection of allergens before and after modifications, to study the residual IgE-binding capacity. Immunoblotting with sera from patients allergic to legumes confirmed the reduction of IgE binding capacity in legume modified samples and digestates. The second part examined novel proteins from mung beans, rapeseed and black soldier flies, evaluating cross-reactivity with known allergens by HR-MS and in silico methods. Mung bean proteins showed homology with soybean and pea allergens, while rapeseed proteins showed cross-reactivity with mustard and legumes. For the black soldier fly, arginine kinase (AK) showed high similarity to other arthropod allergens, confirmed by immunoblotting assays. In conclusion, this research advances the understanding of allergen risk in novel proteins and explores methods to reduce allergenic potential, with the goal of supporting the development of hypoallergenic food ingredients for sensitive consumers.