A review of the toxicological effects and allergenic potential of emerging alternative protein sources

The growing environmental pressure of the animal food chain requires a system shift toward more sustainable diets based on alternative protein sources. Emerging alternative protein sources, such as faba bean, mung bean, lentil, black gram, cowpea, quinoa, hemp, leaf proteins, microalgae, and duckweeds, are being explored for their potential in meeting global protein demand and were, therefore, the subject of this review. This systematic literature review aims to understand the current knowledge on the toxicological effects and allergenic potential associated with these sources and derived protein and food products. The findings identified potential concerns associated with the presence of plant secondary metabolites, including antinutritional factors, phytoestrogens, and oligosaccharides, in all the sources included. Also, these protein sources have been shown to display allergenic properties, either through the intrinsic presence of allergens or through cross-reaction. Further, the effects of food processing on these proteins remain poorly understood and no conclusive data are available to quantitatively assess their safety after processing. Overall, those findings highlight the need for quantitative knowledge of the food safety attributes related to final food products. This will enable a concrete and preventive approach to food safety in the protein transition.