Evaluation and Reduction of Tropomyosin Allergenicity in Commercial Processed Low-Value Shellfish Products

The allergenicity of the major allergen tropomyosin (TM) in commercial low-value shellfish and its processed products was evaluated, and different methods to reduce the allergenicity of TM in edible shellfish tissues were studied. The contents of TM in commercial low-value shellfish and its frozen, dried, smoked or steamed products were analyzed by double-antibody sandwich enzyme-linked immunosorbent assay (ELISA), and shellfish with high allergenicity was selected to explore the effects of traditional (drying, steaming, high temperature and pressure, and quick-freezing) and emerging processing techniques (high hydrostatic pressure, ultrasound, and glycosylation) on reducing tropomyosin allergenicity in edible tissues. The results showed that allergenicity was common in commercial shellfish and its processed products, with TM content ranging from 18.94 to 22.51 ng/g. Among the four kinds of fresh shellfish tested, the TM content of Mactra veneriforimis was the highest, which was (22.51 ± 1.06) ng/g. Compared with untreated Mactra veneriforimis, the allergenicity of dried, steamed or glycosylated samples did not change significantly (P > 0.05). High temperature and pressure, quick-freezing, high hydrostatic pressure and ultrasonic treatment could significantly reduce TM allergenicity (P < 0.05), the effect of ultrasonic (500 W and 30 min) and high temperature and pressure sterilization treatment being more pronounced that of the other treatment, reducing TM allergenicity by 32.4% and 26.9%, respectively. This study provides a theoretical basis and technical support for the development of hypoallergenic processed shellfish products.