Solubility of Iron and Zinc in Selected Seafoods under Simulated Gastrointestinal Conditions

Abstract

Seafoods are known to contain many kinds of minerals, and minerals to be bioavailable need to be in a soluble form. Solubility of iron and zinc from seaweeds (nori, red alga; aonori, green alga; and hijiki, brown alga), mollusks (scallop, clam, surf clam and oyster), and crustaceans (prawn and king crab) was determined under simulated gastrointestinal conditions, and mineral contents in the low molecular weight fraction were estimated by ultrafiltration. The solubility of iron was lower than zinc, however, pepsin-pancreatin treatment increased iron solubility. A larger percentage of both soluble minerals existed in the low molecular weight segment except for iron in mollusks and crustaceans. The solubility of zinc at pH 2 was higher than at pH 6, and also after pepsin treatment was higher than after pancreatin treatment in almost all samples.