E for Additives

3. Golden Eggs and Pink-Fleshed Fish

A happy free-range chicken, able to scratch around for its food and choosing many different pigment-containing and mineralrich items, will usually produce richly golden and strongly shelled eggs. The less fortunate battery hens have to rely upon what is in their feed to give their eggs colour. The most important of these colour-forming substances are, together with other oxygen-containing carotenoids, known by the collective name of xanthophylls (E161).

The xanthophyll content of these fresh feeds is not constant and rapidly degrades during storage periods, so poor colour is a particular problem during the winter months.

Because of the high prices of imported grains compared to those from home, even colour-containing alfafa and maize have been replaced by such cereals as wheat and barley which feed the hens just as well if various fats and soya meals are added, but have no pigments present. A typical laying chicken ration would be as follows:

The egg producer studies his market and knows that eggs for table use sell best if the yolks are a nice golden colour, while eggs used for the manufacture of bakery products, pasta and sauces are better yellow.

Egg yolk colours are measured on a scale from pale yellow to deep orange in shades of 1–15. Table eggs are generally at about No. 11 on the scale, although some producers prefer a very deep orange colour for which they demand higher prices. In practice, the feed supplier helps the egg producer choose the desired colour and then adds concentrated red or yellow pigments of synthetic or natural origin to produce the desired effect which is then checked on a regular basis.

It is known that certain free-range egg producers have added naturally occurring pigments to the ration, especially during the cold months, although the legal situation regarding this does not appear to have been established.

Maize-Fed Chickens

In both France and the United States maize-fed or, as the Americans say, corn-fed, chickens with attractive yellow skins are thought to look and taste better than the white birds preferred in Britain, and the colours can be achieved directly from the xanthophylls in the feed. It is possible to cheapen the diet by using a mixture of cereals and supplementing with pigments, or to add pigments to a maize feed to ensure a deep colour.

It is also possible to produce similarly coloured chickens when the feeds are not fresh, and for this purpose lutein (El6lb), which can be extracted from marigolds, is added to the feed.

Trout and Salmon

There is a long history of trout farming in Britain, certainly going back to the medieval monasteries where farmed trout brightened the Friday fast. Today the farming of salmon, trout and other fish is big business, but have you ever wondered about the great increase in the availability of delicious pink-fleshed trout and salmon? The pink flesh would, in natural waters, be from fresh foods such as crustaceans, shrimp, prawn, lobster (astaxanthin) and various algae.

It is too expensive to feed the farm fish the crustaceans of their usual environment, so a red pigment, canthaxanthin (El6lg), or astaxanthin (no E number), is added to the feed to produce pink flesh. El6lg and certain other pigments, including various forms of carotene and vitamin A, are also sold in tablet form so that we can look as if we have been on a Mediterranean holiday and developed a nice, if often rather yellowish, tan. Be warned though that such coloration gives no protection from sunburn and is there, as in the case of the fish, strictly for appearance’s sake. See additional note on page 374.

Other Uses of Pigments

Pigments are commonly found in pet feeds especially for captive birds so that their colourful plumage is maintained. Zoo flamingos are fed with canthaxanthin to ensure the pinkness of their legs, beaks and feathers. Such commonplace pet foods as dog biscuits and meats often appear to contain significant quantities of undeclared colours. It is doubtful whether these are truly appreciated by the animal, but they do attract the owner.

There are widespread abuses of the external colouring of seafood. For example, jumbo prawns and smoked cod’s roe are frequently on sale in the fish shop without any ingredient declaration, but they have quite often unquestionably been dipped in a heavy concentration of red dye.

Smoked fish is another loophole. Fish can be called ‘smoked’ when all that has happened is that they have been dipped in a liquid smoke flavour and then artificially coloured! Indeed, smoked and cured fish which is not packed ready for the consumer, like ham, just has to say ‘added permitted colour’, but if it is pre-packed the full declaration is required.

Consumer choice means the freedom to make an informed choice and although we think that the use of these artificial and natural additives in animal feeds presents no toxic hazard to the consumer, we do believe that we have a right, as is the case with eggs in the United States, to know what pigments have been added. In addition, acceptable and legally controlled levels of daily intake should be established and enforced. If the egg regulations are so changed, it would be a good opportunity to label egg boxes with the date the eggs were laid and not the less useful date of packing.

4. The Colour Problem

Food has been coloured since ancient times. The Romans coloured bread and wine both with ‘white earth’ and berries. When Britain first imported that rare luxury, sugar, in the twelfth century, the pink- and violet-coloured sugars of Alexandria were, according to John Wallford,1 great favourites. Tyrian purple (from sea snails), madder (from the roots of a herb) and kermes (from a scale insect) are thought to have provided the varying shades of this part of the spectrum.

The red colour of cochineal (E120), was used at least as early as the tenth century by the Toltecs and then the Aztecs of Central America and, as with Egypt and the Mediterranean countries, where the same dyes were used for cloth and for food, it is most likely that cochineal was a food colour.

Many years ago at social meetings of food chemists and before we were in the least worried about the possibility that sweets could rot the teeth (or to be more precise feed the bacteria that do that dark deed), the manufacturers of Newberry Fruits, a range of sweets that were coloured, flavoured and shaped to represent miniature versions of the fruits of which they tasted, gave us a selection of this product in a specially prepared form where all the flavours were jumbled up. Only the most experienced palates could correctly identify a sweet that looked like a strawberry but tasted like a pineapple. So it is clear that colour has a very important role to play in our appreciation and enjoyment of food, affecting not only our eyes but also our taste and even, it is thought, our digestion.

By the same token, colour can influence us into thinking that inferior food that looks attractive also tastes good and is, no doubt, good for us.

Probably the most widely quoted and, in our view, illogical test of the response of the consumer to colour was undertaken by Dr Nathan Goldenberg of Marks & Spencer following certain complaints that their tinned peas were an artificial shade of green and the strawberry jam was an unnatural red. The colours were removed and the peas became grey/green and the strawberries red/brown. The customers stopped buying and it took a long time with the colours restored to bring back lost sales. The reason why this test was so pointless and inconclusive is that there was no clear explanation to the customers as to why the changes had happened and what they might expect when they took the product home. Today we have a completely different situation where very many manufacturers have taken the green colour out of peas and the red out of strawberry jam and have suffered no loss of sales. This seems to show that, with information and education, we can change our perception as to what looks good and tasty.

Added colour is like a cosmetic Like all cosmetics colours can improve the appearance delight the onlooker and deceive the senses. Added colours are not necessary, they are a matter of choice The author had a letter published in The Times on 23 January 1970 which pleaded that, as The World Health Organization had recommended, baby foods should be free from artificial colours, also that we all should be able to tell what is in the food we eat by reading the label. Neither request has yet been granted, but there is hope for babies, for the Food Advisory Committee (FAC) is recommending in its 1987 Report1 that baby foods should be without artificial colours. We do not know how long it will take to turn this recommendation into law but wish it every success. Only in 1986 did it become necessary to label at least most of the ingredients in the foods that we eat. So the battle to have the freedom to choose what we want to, or do not want to, eat is certainly not quick or easy.

The Functions of Colours

Colours have well defined food functions:

(a) to reinforce colours introduced into foods by their ingredients but where, without added colouring matter, the colour imparted to the final food by those ingredients would be weaker than the colour the consumer will associate with the food of that type of flavour (e.g. soft drinks, fruit yogurts, pickles and sauces);

(b) to ensure uniformity of colour from batch to batch where ingredients of varying colour intensity have been used (e.g. jams in transparent containers where the customer can compare like with like in the shop);

(c) to restore something of the food’s original appearance in those cases where the natural colours have been destroyed by heat processing and subsequent storage (e.g. peas, beans, strawberries and raspberries), or bleached out by the use of preservatives (e.g. fruit preservatives, sulphur dioxide for jammaking out of season), or are not light-stable during prolonged storage (e.g. soft drinks);

(d) to give colour to foods which otherwise would be virtually colourless (e.g. boiled sweets, instant desserts, ice lollies).

‘Need’ is an essential reason for deciding that a food additive be used. It could be argued that a reasonable response to at least most of the four categories above would be ‘needed by whom?’. It is clear that in many cases it is the manufacturer that needs the colour, but as we see the removal of many of the artificial colours from the shelves of our shops it is obvious that more colours are being permitted than are ‘needed’ by many responsible manufacturers and retailers, and that these are certainly not demanded by us when we have the choice.

Artificial Colours

In the middle of the last century almost anything that gave colour was used to make food products more attractive. Substances containing mercury, lead, cyanide and copper were frequently used. At about the same time in 1856 Sir William Henry Perkin discovered his first ‘coal tar dye’, which was aniline purple, when he was only nineteen years old. Perkin transformed the cloth industry, whilst at the same time a selection of his colours, which faded less, had a wide range of bright hues and was cheap to use, became available for the food producers.

It did not take long for the regulatory authorities around the world to wonder about some of the colours being used and, depending on where you were, they were either negatively listed, which is to say banned, or positively listed, which means that you could only use those which the government felt were both suitable and harmless according to the scientific standards of the age.

In Britain in 1925 a number of colours which were obviously harmful were banned from use. These included any compounds of antimony, arsenic, cadmium, chromium, copper, lead, mercury and zinc, also one vegetable colour, gamboge (much used by painters), and five of the ‘coal tar’ colours—picric acid, Victoria yellow, aurine, Manchester yellow and aurantia.

It was not until 1954 that the Food Standards Committee proposed that there should be a list of acceptable colours instead of just a list of those that were not permitted. Accordingly, in both 1957 and 1973 lists of both natural and synthetic colours that were permitted were prepared. So what is the position today? Britain permits more artificial colours than almost any other western country. If Norway can manage without any artificial colours and the United States allows seven, we have to wonder why we permit sixteen.

It must be said that some of them seem to cause very few problems, even in those people who suffer from many allergies and intolerances. The toxicological questions and allergic reactions occur most frequently with E110, sunset yellow, and the yellow colour E102, tartrazine. This could be because they are used quite often. More research is needed, but that which is being undertaken at the moment seems to ignore the well-established fact that many people are allergic or badly affected by both foods and food additives, and that often the combination of the food and the food additive together is worse than either alone.

The 1987 FAC Report has certainly made one major step forward, and that is to give proposed average daily intake upper levels for a number of the colours under review. Very many problems with foods and food additives are related to dose and an effort to reduce the level is welcome. However, the FAC has not looked at the question of need from the consumer’s point of view and this could well be an area where the reader will wish to form a personal opinion.

Natural Colours

Professor Frank Curtis, Chairman of the FAC, said in a meeting at the House of Lords in 1987 that he was worried about the increased levels of daily intake of natural colour additives being used, because the tests that had been made on them did not take relatively high levels of consumption into account. This is a fair point. Safety is related to dose. But, having been told that an E-number means that an additive is safe, then it is strange that the natural food colours to do not seem to have been as well tested as we have been led to believe, even though they have received their E-numbers. Nonetheless, so many of them are in common use in a food form that it is difficult to feel really worried about them. For example, if a manufacturer wishes to brighten a strawberry yogurt with beetroot juice instead of E123, amaranth, then the argument goes that the beetroot red colour may also cause problems. On the other hand, beetroot is part of a normal diet whereas amaranth is not.

If we are to be told that colours are necessary for a happy life and a good diet, then certainly a lot more work needs to be done on their safety and necessity, for it is certain that many producers of good food are finding that when they use fine ingredients and first-class methods of conservation the need for colours, artificial or natural, disappears. It is high time we became far less concerned with consistency in the colour of manufactured products, in the way that we do not mind variations of colour in the kitchen. We are already becoming used to a different palette of colours in the foods we eat and this trend will continue as we consume fewer and fewer of those most dispensable of all food additives, the colours.

For a note on some new EC proposals, please see page 374.

1Historical Development of Food Coloration, John Wallford. Developments in Food Colours, Elsevier 1984.

1‘Food Advisory Committee Final Report on the Review of the Colouring Matter in Food Regulations 1973’, HMSO, 1987.