Abstract:

This study investigated quality parameters of soft body tissues of the clam Ruditapes philippinarum such as
anatomic composition, proximate composition, and the distribution of nitrogenous compounds with emphasis on proteins.
The results were indicated that 1) total edible portions accounted for about 20% of Ruditapes philippinarum. Proximate
composition of the edible portions including six tissues, foot, adductor, mantle, siphon, gill and viscera, consisted of moisture
(74.01%–80.07%), protein (29.19%–43.46%, dry basis), carbohydrate (12.46%–30.75%, dry basis), fat (1.61%–6.84%, dry
basis) and ash (6.69%–11.10%, dry basis); 2) the nitrogenous components were distributed in non-protein nitrogen (14.7%–
26.42%), water-soluble protein (12.55%–19.17%), salt-soluble protein (34.83%–50.4%), and alkali-soluble protein (17.49%–
25.06%); and 3) sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the protein
patterns varied among the soft tissues and components, with the water-soluble proteins, salt-soluble proteins and alkalisoluble
proteins distributed below 100 kD, near 200, 100, 45, 35 and 20 kD, and near 200, 100 and 45 kD, respectively, and
the stroma proteins distributed in a wide range, mainly near 45 kD and at 200 kD.

Key words: Ruditapes philippinarum, soft tissues, non-protein nitrogen, protein, composition profiles