Elimination of the major allergen tropomyosin from shrimp muscle by boiling treatment

Abstract

Tropomyosin (TM) is the major allergen found in invertebrates, including shrimp. To reduce the allergenicity of shrimp muscle, attempts were made to eliminate TM from the muscle by boiling. By boiling cubes (~ 1 g) of shelled shrimp muscle in 10 volumes of water (w/v) for 20 min, 7.1% of TM remained as determined by SDS-PAGE. Increasing the boiling water up to 2000 volumes of water did not result in improved elimination. When the muscle cubes were treated at 121 °C for 20 min in 2000 volumes of water, enzyme-linked immunosorbent assay (ELISA) reactivity against TM was reduced to 2.0 × 10−2 fold. After successive second and third treatments under the same conditions, ELISA reactivity was reduced to 4.2 × 10−5 and 1.6 × 10−5 folds, respectively. In addition, TM content in the muscle after the third treatment was lower than the threshold value for mandatory labeling (10 μg of ingredient proteins per 1 g of food). Thus, boiling treatment, especially high-pressure heating, can be an effective method for providing hypoallergenic shrimp for those who are allergic to shrimp and related invertebrates.