The content and nutritional significance of minerals on fish flesh in the presence and absence of bone

The aim of the present study was to evaluate the variations in the mineral contents (Fe, Zn, Cu, Mn, Na, K, Ca, Mg and P) and nutritional significance of the minerals of Mediterranean fish, as a function of the presence of bo ne. The three commercial species analysed were blue whiting (Micromessistiu s poutassou;R), hake (Merluccius merluccius, L) and sole (Solea vulgaris vu lgaris, Q). As small and large species of hake are distinguished commercial ly, they were analysed as separate types of fish. No variations in the cont ents Fe, Zn, Cu, Na and K were observed when bone was included, as the cont ent of trace elements were quite low in all the samples assayed. However, s ignificant increases in the Ca and P contents were observed in all the spec ies analysed when bone was included. To ascertain the nutrional significanc e of the samples they were considered as ingredients of fish-based homogeni sed weaning foods. According to the Ca and P contents, and to the nutrition al density values, the samples could be considered to be good supplements o f Ca and P, when bone is present in the flesh. (C) 2000 Elsevier Science Lt d. All rights reserved.