Thermal processing influences the digestibility and immunoreactivity of muscle proteins of Scylla paramamosain

Abstract

The effects of three kinds of common household processing methods (including boiling, steaming, and high pressure) on the muscle protein of Scylla paramamosain were evaluated. Continuous digestion was modelled by using simulated gastrointestinal fluid and total muscle protein. Scanning electron microscopy was applied to observe the morphology. Circular dichroism spectra and surface hydrophobicity were used to analyze the structures of proteins. Gel electrophoresis and enzyme-linked immunosorbent assay were performed to investigate the digestibility and immunoreactivity of total protein. A more compact and orderly structure of the muscle protein was formed after thermal processing, which meant it was digested more easily. High pressure induced secondary and tertiary structure changes of the tropomyosin in the crude extract, which resulted in a reduction of immunoglobulin G binding activity. All thermal processes, and especially high pressure treatment, could affect the digestibility and immunoreactivity of crab muscle protein by changing the morphology and structure.