Trace element solubility from food following enzymolysis

Food items were treated with enzymes simulating gastric and intestinal digestive juices and the amounts of soluble lead, cadmium, zinc, iron, and copper, were determined. Enzyme treatment was conducted in two stages involving (I) pepsin at pH 2,5 followed by (II) pancreatin and amylase at neutral pH. Solubility was determined after each stage and additionally after post enzymolysis acidification. The foods examined comprised wholemeal bread, spinach, canned tomato, ox liver, pig kidney, canned crabmeat, beefburger, and canned corned beef, the last sampled from within the bulk and adjacent to the side seam of the can. Analyte solubility varied with (I) different food items, (II) processing or preparation of foods of similar origin, (III) action of pepsin or pancreatic enzymes and (IV) pH. Reasons for the variations are discussed.