Abstract
Seasonal changes in the biochemical composition of total tissues and of the visceral, muscle and mantle and gill parts of Mya arenaria oonogai were studied to identify the best season for eating. Specimens were collected for one year from the clam beds on the Wajiro seashore of Fukuoka City for one year. The seasonal variation in the contents of ash, lipid and water were small, while those of protein and sugar, mainly glycogen, were large. Protein and sugar were highest from October to January and from March to June, respectively. The soft body of the clam was separated into the visceral part (gonad, digestive gland, stomach and intestine), muscular part (siphon, foot and adductors) and mantle and gill part (mantle and gills). The wet weight ratio of viscera to total soft body was a maximum in October, a minimum in November and slightly increased until February. The variation of wet weight ratio to total soft body was from 35% to 53% on viscera, 29% to 43% on muscle and 18% to 25% on mantle and gills. The results of the biochemical composition analysis lead us to assume that the best season during which this clam from the Wajiro seashore of Fukuoka City in Northern Kyushu can be eaten is from March to June.
