Influence of Mechanical Separation Upon Proximate Composition, Functional Properties and Textural Characteristics of Frozen Atlantic Croaker Muscle Tissue

Mechanically separated (MS) fish muscle tissue was compared with hand‐separated (HS) tissue to determine their relative effects upon functional properties and final product texture. Proximate analyses revealed that HS muscle tissue was significantly higher in moisture content than MS tissue. MS tissue had significantly higher quantities of sarcoplasmic and nonprotein nitrogen than HS tissue. No significant difference was found between the level of myofibrillar protein for the two treatments, as determined by sodium dodecyl sulfate (SDS, 1%) extraction, although the HS tissue had a slightly higher level. A significantly higher amount of myofibrillar protein and a lower amount of stroma protein was extracted by SDS than by NaCl (0.58M) for both treatments. This difference was attributed to the development of an insoluble sol by the NaCl extraction method which was sedimented as a gel by centrifugation. Stroma protein was significantly higher in the HS tissue for both extraction methods. There was no significant difference between the two treatments for emulsifying capacity or cook stability and these were not related to final product texture evaluated by a sensory panel and instrumental shear force. The texture of the comminuted product prepared with HS tissue was significantly better than that prepared with MS fish tissue.