Development of purity criteria for edible vegetable oils
At the time that this work started, in 1980, there were several large and important international problems concerning edible oil purity and authenticity, such as a problem of cottonseed adulteration with palm oil. It is claimed that a Singapore dealer had secured a contract with the Egyptian government to supply a large quantity of cottonseed oil in two lots. He obtained his cottonseed oil from Australia, but there was a slight shortfall in the quantity and he therefore bulked out the cottonseed oil with a small amount of palm olein, the liquid fraction from palm oil. This went unnoticed and, as a consequence, when the time came for a further delivery, he used a much larger quantity of palm olein. This time the deceit was detected. If he had been successful in this enterprise he would have netted an additional US$14 million in illegal profit. There were other problems of oil purity being faced or suspected by the trade in 1980. Palm oil was fractionated into hard and soft fractions in order to secure advantages of the Malaysian tax and duty structure, which favoured local industry. However, the Western world wished to purchase whole palm oil, and Singapore dealers therefore purchased the palm fractions from Malaysia and recombined them for export to Europe and North America. Unfortunately, the blending was seldom in the same proportions as when the fractions had first been generated and the quality of the ‘palm oil’ therefore varied considerably.
KeywordsErucic Acid Iodine Value Palm Olein Palm Stearin Stable Carbon Isotope Ratio
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