Abstract
Histological and physicochemical changes in the mantle muscle tissue of squid (Sepioteuthis lessoniana) during storage were studied. When raw squid mantles were broken parallel to the circular musculature, the rupture energy (RE) was significantly lowered along with the storage. In the case of breaking across the circular musculature, the RE was slightly lowered but the yield point (YP) in the stress-strain curve shifted to a larger strain during storage. In the case of heated squid meat, the YP shifted to a lower strain during storage. The electron microscopic observation of the muscle tissue of raw squid indicated that a number of voids appeared between the muscle bundles and the muscle fibers during storage, and after cooking, obvious detachment was observed between the muscle fibers and muscle bundles. No significant changes in the molecular sizes of major protein components (muscle fibril proteins) were observed, indicating that the muscle fibril proteins were not degraded.
