摘要：58 Recent brands of refined and processed edible oils and fats (hardened, 49; fractionated, 6; interesterified, 3) were studied for nickel, iron, copper and lead content. 1) The levels of trans -fatty acids in hardened oils were relatively high, but no acids could be detected in fully hardened oils having IV of about 1 or less. Trans -fatty acids were also detected in most fractionated and interestrified oils, and thus should be produced in the hardening process. 2) Nickel concentration was only 0.06ppm or less in refined and processed edible oils and fats, if present at all. Nickel, as a catalyst in hardening process, should be removed almost entirely by refining after hardening. Thus, iron and copper content was 0.20ppm or less and 0.03ppm or less, respectively, these values being nearly the same or less than those in shortenings, as reported previously. Lead could not be found in any sample.
