Cooking methods for spanner crabs Ranina ranina (L.) and their effect on cadmium residues

Abstract

The common commercial boiling time (15 min) for spanner crabs [Ranina ranina L.] is insufficient to inactivate proteolytic enzymes in the hepatopancreas which cause mushiness in the flesh. Boiling, steaming and microwave cooking conditions which did inactivate the digestive enzymes and provide acceptable shelf-life were compared for effects on wt. loss, sensory attributes and cadmium contents in the flesh. Steaming was a suitable alternative to boiling for spanner crabs. Excessive wt. losses and lower sensory scores were found with microwave cooking. Cooking method did not affect cadmium level in the flesh. Many spanner crabs have cadmium levels above the max. permissible concn. of 0.2 mg/kg.