Food Additives and Why They Are Used

MIKE SALTMARSH AND LYNN INSALL

Consumers in modern industrial countries expect a wide range of foodstuffs to be available throughout the year. Supermarket shelves are stocked with fresh fruit, vegetables, meats and fish from many different countries; prepared salads, breads, preserved meats, spreads, part-prepared dishes ready to cook, cooking sauces, confectionery, drinks and chilled and frozen prepared meals for reheating. All these products have to survive the journey from harvest to store and, once purchased, to have an adequate shelflife for the convenience of the consumer. In many markets, prepared foodstuffs are increasingly required to offer the choice of specific nutritional properties, such as reduced fat, energy content or salt. Food additives are essential to enable the food industry in all its forms to make foods that meet these increasingly challenging demands.

It has become commonplace in some circles to criticise food additives, and in so doing, to lump them all together and imply that they are unnecessary, unnatural and generally not good. This approach ignores their diversity of nature, application and origin. It is often suggested that they are added for no good reason, which is not the case. In fact, the law requires that additives must perform a technological function in the foods in which they are used and may be added only in the minimum quantities necessary to perform that function.

Many of the materials we now call additives are not a recent introduction to the food industry but have been used in foods for hundreds of years. Once man had worked out how to obtain more food than needed for immediate consumption, he started to think about how to preserve some of it for times of shortage, such as drought or winter. And when he had established settled communities with a regular food supply, then preparing food to make it more attractive became desirable. There is evidence that Egyptians were using sulfur dioxide to help to preserve wine over 3000 years ago and the Greeks are known to have used a combination of salt and sodium nitrate to preserve meat in the time of Homer. Over hundreds of years, in Europe in particular, international trade increased the range of ingredients available as merchants introduced crops and food ingredients grown by or native to other cultures. Increasingly, cooks and consumers in Europe benefitted from these new ingredients, able for the first time to make cakes, desserts, confectionery, jams and sauces with many of the flavours and textures with which we are familiar today. New preservation techniques such as canning and freezing were added to the tools available to the food producer, and with these and other types of preparation and prepackaging came the requirement for additives such as thickeners, emulsifiers, stabilisers and sweeteners. The challenges posed by lengthening logistics chains, demands for increased convenience, and more recently for reduced fat with no loss of texture, reduced salt with no loss of shelflife, and freeze–thaw stability, have necessitated dedicated research programmes and the development of these more sophisticated additives.

Most countries have a system of approval of food additives, using either the Codex Alimentarius, national or multinational systems. In the EU all additives permitted for use in foods are given a number, prefixed by the letter E. The intention behind the introduction of this system in 1986 was that consumers would find it easier to recognise the number than some of the lengthier chemical names such as polyglycerol polyricinoleate. However, the introduction of the system allowed critics to suggest to consumers that rather than the E number being a mark of approval and safety, it was in fact a cause for suspicion and alarm. Whilst the intensity of the opposition to E numbers has decreased in the EU since then, its legacy persists with "E" numbers being less common on ingredient labels and names being used in preference.

1.1 What are Additives?

The official definition in Europe of an additive, given in Regulation 1333/2008, is "any substance not normally consumed as a food in itself and not normally used as a characteristic ingredient of a food, whether or not it has nutritive value, the intentional addition of which to a food for a technological purpose in the manufacture, processing, preparation, treatment, packaging, transport or storage of such food results, or may reasonably be expected to result, in it or its by-products becoming directly or indirectly a component of such food".

Whilst in most cases it is clear what is an ingredient and what an additive, and the Regulation helpfully provides some examples of what is excluded, even this definition is not entirely precise. For example, salt is an ingredient, vinegar is an ingredient, but if the acid in vinegar, acetic acid, is used alone it must be declared as an additive. Similarly, lemon juice is an ingredient while citric acid, its characterising acid, is an additive.

Food additives have a variety of different roles but in general terms they have two main functions: At the most basic level, they either make food safer by preserving it from bacteria or preventing oxidation or other chemical changes; or they make food look and taste better or feel more pleasing in the mouth.

The use of additives in food preservation is one of the oldest, if not the oldest traditions. Our forebears may not have thought of saltpetre or sodium nitrate, used as a curing agent, or vinegar (acetic acid) used for pickling as additives, but they were essential in maintaining a longer-term food supply of precious perishable foods. Salt, though not an additive by the modern definition, was the other vital ingredient in these preservation techniques.

Alongside their deliberate incorporation into food many additives are also used as processing aids. These are substances that are added either to an ingredient or during the production process, but that do not contribute to the final product. Thus, sulfur dioxide may be added during the peeling and slicing of apples to inhibit browning during the preparation of apple pieces for apple pie. The sulfur dioxide has no role in the final pie, and indeed the majority is driven off during the cooking of the pie. In this instance, the sulfur dioxide is a processing aid as it performs a function during the manufacturing process and is largely absent from the finished product. In the kitchen many of us would use lemon juice to prevent discolouration but this would have a slight effect on flavour. In the food industry, where production is increasingly specialised and expertise focused at specific sites, it is not unusual for the manufacturer of an end product to buy in many of his supplies as part-processed...