Abstract
The determination of phosphorus content in crude and degummed oils, especially soybean oil, is commonly used to monitor the efficiency of the degumming process. Techniques for phosphorus determination are based on calcination of the oil in the presence of zinc or magnesium oxide, followed by phosphomolybdate formation, a subsequent reduction and a spectrophotometric determination of the final product, molybdenum blue. Several reducing agents have been employed, all of which need heating to develop color, and then cooling before the absorbance is measured. The objective of this study was to investigate the use of potassium antimonyl tartrate as a catalyst for the phosphomolybdate reduction with ascorbic acid at room temperature, to evaluate the useful life of reagents, comparative kinetics of molybdenum blue formation (with and without catalyst addition) and the extent of phosphorus recovery, and to compare these results with those from AOCS Official Method Ca 12–55.
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Tosi, E.A., Cazzoli, A.F. & Tapiz, L.M. Phosphorus in oil. Production of molybdenum blue derivative at ambient temperature using noncarcinogenic reagents. J Amer Oil Chem Soc 75, 41–44 (1998). https://doi.org/10.1007/s11746-998-0007-x
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DOI: https://doi.org/10.1007/s11746-998-0007-x