เคมี
เอกสารมาตรฐาน
สหรัฐอเมริกา
AOCS
Ca 17-01
Determination of Trace Elements in Oil by Inductively Coupled Plasma Optical Emission Spectroscopy
2017
3
665.0288 AOCS 7th ed. 2017-2019 rev. Ref.
Solvent-diluted vegetable oils are analyzed for the elements above by ICP-OES. The method determines calcium, copper, iron, magnesium, nickel, silicon, sodium, lead, and cadmium in vegetable oils by ICP-OES. This procedure describes a method to quantify calcium, copper, iron, magnesium, nickel, silicon, lead, sodium, and cadmium in oil. Almost all forms of vegetable oils may be analyzed, from crude oil to degummed, refined, bleached, deodorized, and hardened, and nearly all types of lecithins and phosphatides, depending on dilution solvent. This procedure is suitable only when the elements are present in a solubilized form. When they are present as fine particles (bleaching earth, catalysts, or rust), inductively coupled plasma optimal emission spectroscopy (ICP-OES) analysis results in poor recovery due to nebulization and atomization problems. The only suitable non-ashing direct method for these samples is graphite furnace AAS.