Saltmarsh's Essential Guide to Food Additives

Mike Saltmarsh

• Publisher: Royal Society of Chemistry
• Year: 2020
• eBook ISBN: 9781839161117
• Edition: 5
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

Food additives play a vital role in allowing food manufacturers to provide the range of foods that are available in the developed countries of the world. Additives cover a considerable range from the recognisable sodium bicarbonate used to make cakes in the domestic kitchen to mono- and di-acetyltartaric esters of mono- and diglycerides of fatty acids used as emulsifiers in commercial bread production. They include curcumin, the yellow colour in turmeric, beeswax and citric acid, the acid in citrus fruit, as well as substances prepared synthetically. It has long been fashionable in the media to criticise additives and, in so doing, to lump them all together but this ignores their diversity, their vital role in food production and preservation and the extensive testing they have undergone before being approved. This book outlines why additives are used, the testing regime within Europe, and a complete listing of all additives permitted within the EU.

The law covering food additives in the EU, which was harmonised in 1989, has been revised a number of times, most recently by the publication of Regulations 1333/2008 and 1129/2011. These Regulations have been amended a number times with additives being removed or added. This fifth edition of the Guide brings it up to date with a revision of every chapter to reflect the current situation.

Providing an invaluable resource for food and drink manufacturers, this book is the only work covering in detail every additive, its sources and uses. Those working in and around the food industry, students of food science and indeed anyone with an interest in what is in their food will find this a practical book full of fascinating details.

Chapter 1

Food Additives and Why They Are Used

Mike Saltmarsh

Inglehurst Foods Ltd, UK

Email: [email protected]

A look at the shelves of any supermarket in the developed world will reveal a vast range of foods, of different flavours, colours and textures from many cuisines, which pay tribute to the skill of chefs, scientists and engineers in the food industry and the companies that provide them with ingredients and additives. What we now call food additives are the result of over 2000 years of creativity in the food industry. Once man had progressed from nomadic hunter/gatherer to living in settled communities he needed to work out how to store food for times of shortage. Meat was salted, smoked, dried or frozen according to location, and the relationship between bread and beer was established. Then, as with many technologies, it was the Romans who really started the food industry, actively seeking out the novel and ingenious as professional cooks were always on the lookout for fresh ideas to stimulate the palates of their masters. This drove the trade in pepper, for example, but also led to the use of albumen or fish gelatin for fining wine and copper for keeping greens green during cooking. As international trade increased over the years, cooks in the richer countries used commodities that were becoming available, generally from the East, to make delicacies for their employers. The development of retail trade in the 19th century, driven by new technologies and consumer power, generated the need for new ingredients, some of which we would now call additives, so that products that had once been the preserve of the rich could be available to all. Up until the end of the 18th century, new ingredients in Europe had all been used in other countries for some time, but the new understanding of science meant that the substances coming forward in the 19th century were novel, producing foods which had not been seen before. As an example, sodium bicarbonate started to be used in conjunction with sour milk to produce lighter cakes than had been possible with just eggs or yeast. The mixture of this compound together with potassium hydrogen tartrate produced the first consistent baking powder. The development of other mixtures of what are now called raising agents has allowed a vast range of cakes, buns, rolls and breads to be made available, either freshly baked or frozen part baked for later finishing. More recently, the challenges posed by long logistics chains and increasing consumer demands for increased convenience, lower fat without loss of texture, reduced salt with no loss of shelf life and reduction in the use of sugar with no loss of palatability, have all put increased demands on the technical requirements of thickeners, emulsifiers, stabilisers and sweeteners.

Over time, countries introduced systems of controlling additives, some using lists of compounds that were permitted, others of compounds that were banned. When the countries of the EU first came together to draw up an agreed list of permitted compounds and to determine how they should be described in an ingredient list they decided that, because some names were rather complicated, it should be acceptable to use a number instead of a name. The number was to be preceded by a capital ‘E’ to indicate the additive had been assessed and determined to be safe. Companies took up the use of numbers as it simplified the ingredient declaration, but for some organisations this highlighted the number of additives in some products and gave them the opportunity to cast doubts on their safety. In response the use of numbers has decreased and the name, even of the more complicated compounds, is now being used in preference.

1.1 What are Additives?

The official definition of a food additive, as provided in the Procedural Manual of the Codex Alimentarius Commission¹ is:

“any substance not normally consumed as a food by itself and not normally used as a typical ingredient of the food, whether or not it has nutritive value, the intentional addition of which to food for a technological (including organoleptic) purpose in the manufacture, processing, preparation, treatment, packing, packaging, transport or holding of such food results, or may be reasonably expected to result, (directly or indirectly) in it or its by-products becoming a component of or otherwise affecting the characteristics of such foods. The term does not include ‘contaminants’ or substances added to food for maintaining or improving nutritional qualities.”

In other words, a food additive is a compound that is specially selected to do a specific job in a food product. It may be a natural product, like beeswax, a chemical identical to one found in nature, like citric acid, or an entirely new compound, like saccharin.

This definition is the basis of the definition given in the European Commission's Regulation (EC) No. 1333/2008,² Article 3 of which provides the list of substances which are not to be considered additives. Thus salt is an ingredient, rather than an additive, as is vinegar, but the acid in vinegar, acetic acid, is an additive. Similarly, lemon juice is an ingredient but the acid that provides its characteristic acidity, citric acid, is an additive. This principle, that the original material is an ingredient but a selectively extracted component is an additive, is applied widely and is extended to the use of colours and colouring foods.

It is important to notice that some materials which are referred to in common speech as food additives are classified in the Regulation as ingredients; this would include materials such as high fructose corn syrup.

The Regulation as amended³ identifies 27 different classes of use for additives in the EU: sweeteners, colours, preservatives, antioxidants, carriers, acids, acidity regulators, anticaking agents, antifoaming agents, bulking agents, emulsifiers, emulsifying salts, firming agents, flavour enhancers, foaming agents, gelling agents, glazing agents, humectants, modified starches, packaging gases, propellants, raising agents, sequestrants, stabilisers, thickeners, flour treatment agents and contrast enhancers. These are expanded in the following sections.

1.1.1 Sweeteners

Sweeteners perform an obvious function and they fall into two broad groups. One group is sweeter than sugar, often several hundred times sweeter, and the other is less sweet. The intense sweeteners, including saccharin, aspartame and sucralose, are roughly 300 times sweeter than sugar, so are used in very small quantities. This means that while they can be used to replace the sweetness of sugar in low-calorie products, they cannot replace the bulk. The other group, bulk sweeteners, are the polyols – maltitol, xylitol, and so on. These are about 80% as sweet as sugar so in some products sugar is replaced by a mixture of an intense sweetener and a bulk sweetener. It should be noted that while these products are sweet, their sweetness is different from that of sugar. Some sweeteners have a very intense initial sweetness, while with others the sweetness develops more slowly and lingers longer, and most artificial sweeteners have a bitter aftertaste. The search is still on for sweeteners, particularly ones extracted from plant material, that replicate sugar more closely. As an example, a fruit native to China and Thailand and used in Chinese traditional medicine, monk fruit, is currently permitted in the USA but not in Europe.

1.1.2 Colours

The role of colours is also obvious, although sometimes they are used to replace colour that has been lost in processing and sometimes just to make products more appealing. Colour is an important marker for consumers – orange drinks are supposed to be orange, and raspberries are supposed to be red. Sometimes the natural colour of products is lost during processing, for example during canning or bottling, and this colour needs to be replaced.

The use of colours to make food more appealing has a long history but they have had a bad press, particularly after the publication in 2007⁴ of a study into the effect of a group of six colours and sodium benzoate on the behaviour of young children. As a result, the use of colours has decreased considerably and they have tended to be replaced by coloured foods, such as pumpkin, black carrot and safflower. This is discussed in more detail in Chapter 4.

1.1.3 Preservatives

Preservatives are substances that protect foods against deterioration caused by micro-organisms, such as bacteria, yeasts and moulds. The micro-organisms could make the food taste bad or food poisoning bacteria could grow to unsafe levels, or they could produce toxins that would make consumers ill. Preservatives are thus an important part of the food safety measures in our food supply. They are important in extending the shelf life of foods, for example to allow for less frequent shopping expeditions and the longer supply chains needed for our modern food industry. Preservatives have a very long history, going back to the use of salt, sodium nitrite and spices to preserve meat. The most common preservative until recently was sodium benzoate, but its use decreased when it was discovered that parts per million levels of benzene could be formed in drinks containing sodium benzoate and vitamin C when exposed to sunlight. It has generally been replaced by potassium sorbate.

1.1.4 Antioxidants

Oxygen can cause changes in food which lead to off-flavours such as rancidity in fats and to loss of colour and flavour. This sort of oxidation is a chain reaction so it needs to be inhibited before it starts – antioxidants cannot restore oxidised foods. Oxygen also reacts with some vitamins, so that the amount of the vitamin decreases during storage. There are a number of ways to minimise the adverse impact of oxygen on food in storage (in addition to the use of antioxidants), including replacing the oxygen in a package with an inert packaging gas, removing the oxygen using enzymes or incorporating UV-absorbing substances in transparent packaging. Some antioxidants work by being oxidised themselves, like ascorbic acid, while others interfere in the mechanism of oxidation, like butylated hydroxyanisole (BHA), the tocopherols and gallic acid. All have specific properties making them more effective in some applications than in others. Often a combination of two or more antioxidants is more effective than one alone because they are synergistic. Sometimes metal ions catalyse the oxidation and a sequestrant such as citric acid is used to bind to the metal ion and increase the effectiveness of the antioxidant.

1.1.5 Carriers

Many flavours are liquid, so they need to be either absorbed or encapsulated in order to be used in dry products. The materials that perform this function are carriers. Some colours are intense and need to be diluted in order to be mixed evenly through a product. Again, the powders used for this dilution are called carriers.

1.1.6 Acids

Acids are used to provide an acid or sour taste to foods or to increase the acidity (decrease the pH) of a food to inhibit the growth of harmful organisms. Many acids are available, each with its own characteristic taste. The organic acids, e.g. citric, malic, acetic, are generally used for their taste while inorganic acids such as hydrochloric, sulfuric and nitric, are used in very small amounts to reduce pH. An exception is lactic acid, which is used to reduce the pH of bottled vegetables because it reduces the pH while having a particularly mild acid taste.

In contrast to the acids, sodium and potassium hydroxide are used to raise the pH in some products.

1.1.7 Acidity Regulators

The taste of the organic acid alone is usually quite sharp and a salt of the acid is commonly used to moderate the taste. These salts are called acidity regulators.

1.1.8 Anticaking Agents

Food powders are not necessarily free-flowing and this can cause problems in mixing and dissolving. Other powders tend to absorb water from the environment and form a solid mass. These problems can be overcome by using an anticaking agent, a fine powder that coats the surface of the particles and both stops them caking and acts as a lubricant so that the powder flows freely.

1.1.9 Antifoaming Agents

When soft drinks, hot jams and jellies are being filled into containers it is important that the lip of the container stays clean for subsequent sealing. Antifoaming agents are used to stop the product foaming as it is filled.

1.1.10 Bulking Agents

When intense sweeteners are used to replace sugar, very little sweetener is needed so there are occasions when a bulking agent is needed to replace the volume that was taken up by the sugar. This is particularly the case with table-top sweeteners, where a tiny amount of sweetener (1/60 g) would be needed to replace a teaspoon of sugar. This is too small to measure and...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Chapter 1 Food Additives and Why They Are Used
• Chapter 2 Safety of Food Additives in Europe
• Chapter 3 European Union Controls on Food Additives – A Historical Overview
• Chapter 4 Food Additive Regulations in Europe
• Chapter 5 Individual Additives: Additives Permitted in the EU in 2020
• Appendix
• Subject Index