An Overview of Seafood Allergens: Structure–Allergenicity Relationship and Allergenicity Elimination Processing Techniques

Seafood (fish, crustacean, and mollusk) allergy represents a critical global health issue. Food processing offers a viable strategy for allergenicity mitigation and serves as a critical intervention for seafood allergy prevention. This paper reviews recent advances in seafood allergen research, with particular focus on molecular properties, epitopes, and structure–allergenicity relationships, which are foundations for designing processing technologies to mitigate allergenicity. Furthermore, an analysis of how various food processing techniques modulate allergen structures and epitopes, ultimately affecting their allergenicity, was conducted. Current World Health Organization (WHO)/International Union of Immunological Societies (IUIS) listings include 44 fish allergens and 60 shellfish allergens, with their characterization enabling targeted processing approaches for allergenicity elimination. Physical processing techniques, including thermal and non-thermal treatment, can dramatically influence the conformational and linear epitopes by altering or destroying the structure of an allergen. Chemistry-based processing techniques (enzymatic-catalyzed cross-linking and glycation), which induce covalent/non-covalent interactions between allergens and various modifiers, can effectively mask epitopes through molecular complexation. Biological processing attenuates allergenicity by inducing protein unfolding, polypeptide chain uncoiling, and enzymatic degradation. Nevertheless, the structure–activity relationship of seafood allergens remains insufficiently elucidated, despite its critical role in guiding processing technologies for allergenicity elimination and elucidating the fundamental mechanisms involved.