Colourings: artificial

If the wool thus obtained, after thorough washing with cold water, is coloured distinctly red, the conclusion may be drawn that the wine was coloured artificially with an organic dye of acid character, i.e., with a sui-phonated azo- or fuchsine derivative (vinolin, Bordeaux red, etc.)... 

In White Wines.—White wines may be coloured artificially with caramel or artificial organic dyes (substitutes for caramel, caramelin). The latter are detected as in red wines in this connection it should be borne in mind that the yellow colours usually added to wines do not consist of individual colouring matters but are mixtures of a yellow material with a brown, a red or, sometimes, a blue compound. 

Factis is, however, often sold mixed with various extraneous matters such as mineral substances, mineral oils, vaseline, or paraffin wax, resins or resin oils, bitumen, tar, etc. Further, white factis may be coloured artificially by organic colouring matters soluble in fats. 

The many possible oxidation states of the actinides up to americium make the chemistry of their compounds rather extensive and complicated. Taking plutonium as an example, it exhibits oxidation states of -E 3, -E 4, +5 and -E 6, four being the most stable oxidation state. These states are all known in solution, for example Pu" as Pu ", and Pu as PuOj. PuOl" is analogous to UO , which is the stable uranium ion in solution. Each oxidation state is characterised by a different colour, for example PuOj is pink, but change of oxidation state and disproportionation can occur very readily between the various states. The chemistry in solution is also complicated by the ease of complex formation. However, plutonium can also form compounds such as oxides, carbides, nitrides and anhydrous halides which do not involve reactions in solution. Hence for example, it forms a violet fluoride, PuFj. and a brown fluoride. Pup4 a monoxide, PuO (probably an interstitial compound), and a stable dioxide, PUO2. The dioxide was the first compound of an artificial element to be separated in a weighable amount and the first to be identified by X-ray diffraction methods. 

Many colour reactions have been soggested (or differentiating between the oils 01 gnnltheria and sweet birch and artificial methyl salicvlate. Most of ihese are unsatislactofy, ilie onlv oue which yields uaelnl results iu the author-s opinion beiujj that of Cmney, w hich is as follows -... 

Essence of Vanilla.—The substance sold under this name is, properly, a spirituous extract of the vanilla bean. Many samples, however, are little more than alcoholic solutions of artificial vanillin, coloured with caramel. Some samples, which cannot be described as adulterated, contain a little coumarin or other odorous substance, added to varj- the characteristic vanillin odour and flavour somewhat. 

Tests for Caramel.—Valuable indications of the nature of an extract are obtained in the process of determination of vanillin and coumarin. Pure extracts of vanilla beans give, with lead acetate, a bulky, more or less glutinous, brown-grey precipitate, and a yellow or straw-coloured filtrate, whereas purely artificial extracts coloured with caramel give a slight dark brown precipitate and a dark brown filtrate. If both vanilla bean extract and caramel are present the precipitate is more or less bulky and dark coloured, and the filtrate is more or less brown. The soluticm remaining after extraction of the vanillin and coumarin with ether, if dark coloured, should be tested for caramel. 

Consumers will have to choose to have less choice . It has to be recognised that much of the choice in the food market is spurious, an illusion of artificial colours, flavours and additives. It is also wasteful of the fossil fuels used to transport foods all over the world and harmful to local farmers and communities. In the USA (Stauber, 1997) rural America is no longer agricultural America, with only about a quarter of rural counties, mostly in the Midwest, dependent on agriculture. 

This book reviews one extensive group of substances, flavourings (Chapter 9), that is being brought into international controls on additives. It also considers three major groups of widely-controlled additives in detail artificial sweeteners (Chapter 10), substances used as colourings (Chapter 8), and antioxidants (Chapter 12). A more general review of the other additives and how they are controlled is presented in Chapter 11. 

FRAZIER R A, INNS E L, DOSSI N, AMES J M and NURSTEN H E (2000b), Development of a capillary electrophoresis method for the simultaneous analysis of artificial sweeteners, preservatives and colours in soft drinks ,... 

An electrophoretic method was developed for the simultaneous determination of artificial sweeteners, preservatives and colours in soft drinks. The samples were degassed by sonication, filtered and used for analysis without any other pretreatment. Measurements were realized in uncoated fused-silica capillaries, the internal diameter being 50 ptm. Capillary lengths were 48.5 cm (40 cm to the detector) and 65.4 cm (56 cm to the detector). Capillaries were conditioned by washing them with (1 M sodium hydroxide (10 min), followed by 0.1 M sodium hydroxide (5 min) and water (5 min). Samples were injected hydrodinamically (250 mbar) at the anodic end. Analyses were performed at a voltage of 20 kV and the capillary temperature was 25°C. Analytes having ionizable substructure... 

Food additives such as preservatives, sweetening agents, flavours, antioxidants, edible colours and nutritional supplements are added to the food to make It attractive, palatable and add nutritive value. Preservatives are added to the food to prevent spoilage due to microbial growth. Artificial sweeteners are used by those who need to check the calorie Intake or are diabetic and want to avoid taking sucrose. 

The quest for artificial gold has never ended. The Swedish writer August Strindberg convinced himself that he had made it alchemically in 1894 but this at least was one claim susceptible to chemical disproof, for his gold turned out to be a gold-coloured compound of iron a variety of fool s gold. 

Concern about food additives became so significant that food producers managed to seduce consumers with the prominent labels proclaiming free from artificial flavours or no artificial colouring . Such additives were blamed by some as being responsible for criminal, disruptive or violent behaviour of children. Food labelling, either under voluntary codes or by law, was introduced in response to such concerns. In Europe, the adoption of E numbers to identify commonly used food additives supposedly helped consumers make informed choices (or possibly helped alleviate some public fears). 

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