Correlation of chromatographic absolute loss determinations with the A.O.C.S. Cup Refining method in soybean oil

Summary It can be concluded, on the basis of our experiments, that chromatographic loss determinations can be well correlated with A.O.C.S. Cup Refining determinations. This correlation is good for samples above 1% chromatographic losses and somewhat less accurate for samples below 1.0%. Most of the discrepancy in correlation is inherent in the Cup Loss method because it is less precise in general than the chromatographic determination. On the other hand, the chromatographic loss is an accurate, easily obtainable index for unavoidable losses resulting from the nonneutral oil fraction of the oils. In the majority of cases the degumming of the oil to levels below 1% chromatographic loss is not indicated by a parallel decrease in cup losses. Thus, in these cases, as long as premiums are paid on the basis of the A.O.C.S. Cup Loss method, the processor is placed in a very disadvantageous position. It should be pointed out that all our determinations were made on the oils from the 1956 crop during the summer months. The possibility that different crop years will result in different correlation curves might exist, and we are planning to do further work in the future. It is hoped that by presenting statistically significant figures on this subject, enough interest will be stimulated for more collaborative work, which might result in a review of the industry's present method for the determination of refining losses in soybean oil.