Abstract
The study dealt with the relationships between the quality of nori fronds and the diatoms attached to them in the nori cultivation ground. The investigations were carried out for quantita-tive analyses of total nitrogen and total phosphorus in each frond collected monthly and classified into five specimens according to the cell numbers of diatoms.
The quality gradually declined after the middle period of cultivation, and declined further as the diatoms were attached to the fronds. The contents of total nitrogen and total phosphorus were high in the fronds with few cell numbers of diatoms, and as the cell numbers increased, the contents decreased. It was concluded that in the case of the fronds with over 2.5×104 cells/cm2 of diatoms attached, the fronds were inferior in quality. The validity was ascertained on commercial sheets of dried nori.
