Adulteration process appearance

It transpired that the toxic oil was rapeseed oil that had been adulterated by the addition of 2 per cent of a chemical called aniline, as required by law in Spain for imported rapeseed oil so that it cannot be used for cooking. This oil had been refined and was sold for human consumption, as had been done before without adverse effects. It would appear that a batch of oil may have been refined differently or somehow became contaminated. The toxic oil was found to come from only one source within a particular refinery. The Spanish government agreed to replace the suspect oil with pure olive oil, after which the number of new cases subsided. Collection of contaminated oils known to be associated with the syndrome for analysis was a difficult task due to the government exchange programme. The results showed that the oil associated with the syndrome had a similar composition to rapeseed oil and contained contaminants as a result of the added aniline and the subsequent refining process. 

Compounds formerly named nature identical are to be de ned by law since some years as synthetic products. These molecules have been found in nature by analytical proof and are published in an authorized scienti c journal. The term nature identical is no more valid and allowed in Europe in relation to avor and fragrance substances. Such molecules are identical with those appearing in nature but are produced by a synthetic process. These processes contain undesired by-products. The use of such synthetic compounds is easy to detect, as by-products from manufacturing can easily be detected by GC-MS systems. On the other hand, chiral separation will help to con rm adulteration. 

Part of the motivation for these researches was the attempt to develop a potash industry in the north American colonies, which could compete with the high-quality products available from Sweden and Russia. In response to concerns from the government of Massachussets that its potash was being adulterated, the London-based Society of Arts became involved in the development of tests for adulteration. One of these tests was a more precise form of titrimetry, developed by WiUiam Lewis. Using his titrimetric tests Lewis detected large amounts of lime and sea-salt in the potash samples and described them as adulterants. Dossie, who was also concerned with potash, but had a recipe which he had himself devised which he wanted to promote, reached an exactly opposite conclusion. What appeared to be adulterants were simply indications that the excellent process by which the potash had been prepared had been performed imperfectly. The Americans were honest but manufacture was hard. When it was done rightly, by contrast [23] ... 

More empirical methods for detecting adulteration in turpentine have been published than is the case for any other essential oU. These are principally based on colour reactions, and are, in very many cases, quite useless, especially when the adulterant is carefully puiwed. Many modifications of processes described above have been published, but do not appear to possess any advantages over those which have been described. It is, therefore, considered unnecessary to reproduce so large a bulk of published work, which has so little bearing on the practical examination of this oil but readers who wish for information on these or other little-used processes or tests, or for details of methods which for any other reason are not dealt with here, are referred to the following papers —... 

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