Full Length Research Paper

The biochemical textural and sensory properties of frozen stored (-22˚C) king scallop (Pecten maxinus) meats

Maria Makri

Aquaculture and Fisheries Department, Technological Educational Institute of Messolonghi, Nea Ktiria 30200, Messolonghi, Greece. E-mail: mmakri@teimes.gr.  Tel.:+302631058204. Fax: +302631058287.

Abbreviations: HADH, β-Hydroxy-acyl-coenzyme A dehydrogenase activity; TBARS, thiobarbituric acid reactive substances; TCA, trichloroacetic acid.

Accepted 15 June, 2009

Post-rigor king scallop meats (Pecten maximus) were frozen individually for 24 h at -80°C and kept  vacuum packed at -22°C for up to 301 days. Sampling was carried out on fresh meats and at days 1, 28, 91, 154, 210 and 301 of frozen storage. Tests related to muscle integrity (β-hydroxy-acyl-coenzyme –A dehydrogenase activities in muscle extracts), myofibrillar protein denaturation (Ca²⁺-ATPase activities in actomyosin extracts) showed that storage time affected the integrity of muscles and caused structural changes to myosin (or ‘actomyosin’). The water holding capacity (expressible fluids) of the frozen stored scallop meats decreased with storage time and was associated with the denaturation of myofibrillar proteins. The peak shear forces of frozen stored scallop meats, as measured by the Warner-Bratzler shear knife, did not change with storage time, indicating that the length of time of storage at -22°C did not affect the tenderness of the raw scallop meats. The storage time affected the sensory attributes (flavour, texture and acceptability) of the frozen scallop meats, but these products were in acceptable eating condition after a storage period of ten months. Ca²⁺-ATPase activities in actomyosin extracts may be useful for assessing the quality loss of the frozen stored scallop meats, since a good linear correlation was obtained with storage time and scores of sensory attributes.

Key words: Scallop meats, frozen storage, quality, enzymes.