Decrease in organic solvent extractable ethion by grapefruit pectin during processing.

摘要

The effect of food components on pesticide residues was examined using citrus fruit often heated to make marmalade. Commercial grapefruit was peeled, and the parts were fractionated by extraction with several kinds of solvents (n-hexane, acetone, methanol, and water). The amount of organic solvent extractable ethion remaining after heating was smallest in the crude peel water extract. Purification of the water extract by deposition with methanol and dialysis produced a gel. The gel reduced the amount of several organophosphorus pesticides extracted by organic solvents during heating. From the IR spectra, the chief ingredient of the gel was considered to be pectin, which is contained in most plants. Thus, the pectin of grapefruit was considered tohave masked organophosphorus pesticides from organic solvent extraction. Pectin is easily transused from foodstuffs by cooking and appears to play a role in reducing the amount of pesticide extracted by organic solvents with heating.