Alan, Tropomyosin is not the only allergen in seafoods. Indeed many allergic responses are due to non-contractile proteins in the food. Regarding tropomyosin, it is one of the most highly helical proteins known. Hence it is quite stable. Unfortunately this does not answer the question as to whether it is still effective as an allergen.
Several proteins are strong allergens even in their unfolded state.
Even more so than the native protein in a few exceptional cases. I would appreciate any feedback that group members have to offer.