1996 Volume 37 Issue 4 Pages 210-214_1
The concentrations of heavy metals in commercial natural food additives (9 items, 10 products) used to increase the shelf life of foods were determined. Pb content was below 3μg/g in all items, though some items contained about 10μg/g of Cu or over 200μg/g of Fe. The influence of Cu and Fe on the Heavy Metals Limit Test was investigated using the items that contained large amounts of Cu or Fe. Although not darker than the color of the control solution (the limit was set at 20μg/g as Pb), darkening was observed in the test solution of the pepper extract that showed the highest concentrations of Pb and Cu. Since the color of 100μg/g of Cu corresponded to that of 40μg/g of Pb, Cu in the pepper extract contributed more to the darkness than the Pb. In an HPLC-ICP study on a neutral solution of pectin digests, an Fe peak, which may be ascribed to Fe bound to galacturonic acid, was observed. Since various metals are present in commercial products of natural food additives, it is considered that specifications for, at least, lead, heavy metals, and arsenic should be established for natural food additives.
