The additives used today are primarily used for the following reasons:

• to ensure that food remains hygienic until it is consumed, thus avoiding the risk of food poisoning (e.g., by adding preservatives),
• to provide a range of food that is appropriate to its price,
• to extend shelf life and preserve flavour (e.g., through antioxidants),
• to improve the nutritional value (e.g., by adding minerals),
• to change or maintain consistency (firmness, spreadability, etc.) (e.g., by adding emulsifiers or gelling agents),
• for a wider range of calorie-reduced foods,
• to ensure consistent quality,
• for stockpiling,
• to preserve seasonally independent foods.

Safety is an important criterion. However, the fact that an additive is safe is not a "carte blanche" for its use. Its technological necessity must also be justified. Failing this, no authorization will be granted, even if the additive is safe. A new substance is not approved until it is very clearly shown that this additive is both safe and necessary. Furthermore, customers must not be deceived using additives. Certainly, no additive may be used to conceal faulty processing or to cover poor quality raw materials.

Many additives are suspected of causing intolerances in people who are susceptible to them. However, most allergies are caused by certain proteins in food - i.e., by natural ingredients and not by additives.

There is hardly any food to which someone does not react somehow.

Scientific studies show that, as a rule, one in 10,000 persons reacts hyper-sensitively to additives. In other words, hypersensitivity reactions caused by additives are particularly unlikely. They can be avoided if those affected study the list of ingredients very carefully or inform themselves in some other way, e.g., by asking the manufacturing company. With the labelling in the menus, the Studierendenwerk would also like to give those affected the opportunity to inform themselves.

Colorants are applied to improve the appearance of food. They must not exceed the colour of the fresh food. In order not to deceive consumers, the words "coloured" or "with colorant" must be immediately apparent and clearly legible for them on the packaging or menu.

Exception: If, for example, salad with feta contains black olives, it must be labelled. Black olives are coloured with ferrous gluconate or ferrous lactate to simulate the deep black colour of a ripe olive. Here the consumers must be informed with the word "blackened".

These additives are used in food to delay or even prevent microbial spoilage of food by bacteria, fungi, and yeasts. Some are applied only for surface preservation, e.g., fruits - here the pores on the skin are sealed and prevent the penetration of fungi. The others are added to the food and prevent food spoilage, e.g., mould in sliced bread. Preservatives are identified by the words "with preservative" on the package or menu. Probably the best-known preservation is that of curing. The use of nitrite curing salt is the most effective method of preventing food spoilage in meat. Botulinum toxin, the most potent biological toxin of the bacterium Clostridium botulinum, cannot be killed by heating alone. The application of nitrite is the only way to prevent it.

Antioxidants counteract or slow down oxidation, preventing food spoilage by atmospheric oxygen, for example, the degradation of air-sensitive vitamins is inhibited, or fats are prevented from turning rancid. The latter is one of the main tasks of antioxidants, which are used, for example, in instant soups, edible fats, etc. - in other words, in many fatty foods.

These additives intensify the taste of certain flavours lost during processing. They are particularly used in products where water has been removed or which have been preserved by heat or deep freezing - e.g., instant soups, grained broth, etc. They are also used in convenience foods. The label "with flavour enhancer" is sufficient.

This multi-purpose substance is used for sulfurizing, i.e., for killing bacteria and moulds, among other things when cleaning wine barrels or preserving foodstuffs. Labelling is done with the word "sulfurized".

Coating agents protect chunky foods (e.g., cheese wheels such as Edam or also fruit) from drying out, loss of flavour, quality, and spoilage. They are waxes and resins applied to the surface warm or as an emulsion by spraying or dipping, forming a solid, elastic surface film. The corresponding food products are recognizable by the information "waxed".

Phosphates are vital components of our organism, for example, they are involved in the construction of DNA. Thus, they are naturally present in practically all foods. However, they are mainly found in protein-rich foods such as milk, meat, fish, and eggs. Phosphates are used as additives in the food industry in the form of polyphosphates, for example, to soften water, as a melting salt for processed cheese or in the production of cooked sausages, surimi, or fish fingers. The phosphate content of beverages containing cola is also very high. When used in meat products, the indication "with phosphate" appears on the menu.

Sweeteners (sweeteners and sugar substitutes, except fructose) are used in foods in which a sweet taste is to be achieved but sugar is to be omitted - e.g., in calorie-reduced foods. These foods can be identified by the words "with sweetener".

Phenylalanine is an essential amino acid for humans that plays an important role in nitrogen metabolism. The liver can convert phenylalanine - if sufficiently present - to tyrosine. The normal daily dose should be 14 mg/kg body weight (of an adult) and it is basically sufficiently covered by food. Phenylalanine is involved in the synthesis of adrenaline, noradrenaline, and other hormones. It serves as a metabolic derivative for many other substances, e.g., important messenger substances of the brain (dopamine, serotonin, tyramine).

In the hereditary metabolic disorder phenylketonuria, or PKU for short, the amino acid phenylalanine cannot be broken down to tyrosine in the body of the affected person. The information "contains a source of phenylalanine" is therefore relevant for those affected by PKU and is made in the presence of the additives aspartame and aspartame-acesulfame salt.

In some cases, people with food allergies can develop life-threatening reactions after eating even the smallest quantities of the intolerant food. Therefore, when eating food that has not been prepared by the person him-/herself, the risk and fear of developing an unintentional allergic reaction are significant. In order to improve the quality of life of these people in this respect, the 14 most common allergens are labelled when they are used as an ingredient in the food in question.

In an allergy, the immune system develops antibodies against substances that are completely harmless, such as food. If these foods are eaten repeatedly, the immune system responds with sometimes very serious immediate reactions such as shortness of breath, hives (urticaria), itching and swelling of the skin or mucous membranes, gastrointestinal complaints and/or circulatory problems, and even unconsciousness.

Food intolerances are very diverse and can occur, for example, when consuming food additives, lactose, or fructose. The immune system is not involved here. It is more likely that gastrointestinal complaints occur (lactose intolerance, fructose intolerance) or also symptoms on the skin (after consumption of food additives).

The EU Food Information Regulations (LMIV) No. 1169/2011 require that all dishes offered as part of mass catering must be labelled according to their content of declarable allergens. The regulations apply to up-market restaurants, cafeterias, and canteens as well as to simple snack bars.

An allergen is defined as a wide variety of small protein structures that can be found, for example, in plant and animal foods. As a rule, these proteins are completely harmless. However, if the immune system mistakenly forms antibodies against these harmless substances, contact with the allergens leads to sometimes severe overreactions of the immune system. Since the only therapy for an allergy to certain foods is to avoid them, it is of utmost importance for people with allergies to find out which allergens may be present in foods they do not prepare themselves. It is the only way they can protect themselves from unconscious contact with allergens.

The following 14 most common food allergens must be labelled:

• Cereals containing gluten and products made from them (wheat, rye, barley, oats, spelt, kamut)
• Crustaceans and their products
• Eggs and their products
• Fish and their products
• Peanuts and their products
• Soya and its products
• Milk and dairy produce (including lactose!)
• Nuts and their products (almonds, hazelnuts, walnuts, cashew nuts, pecans, pistachios, Brazil nuts, macadamia, or Queensland nuts)
• Celery and its products
• Mustard and its products
• Sesame seeds and related products
• Sulphur dioxide and sulphites (10mg/kg or more or 10mg/l) and related products
• Lupins and related products
• Molluscs and their products

In accordance with the current Food Information Regulations No. 1169/2011, the 14 declarable allergens must only be listed if they are added directly to a dish as an ingredient according to the recipe - regardless of the quantity (exception: sulphur dioxide). Traces, i.e., unintentional contamination of a dish with the allergens mentioned, do not require labelling from the legal point of view. Since cross-contamination can never be excluded in commercial kitchens, traces are not labelled by the Studierendenwerk Thüringen.

In scientific literature, there is no precise information on the temperature and time at which ALL allergens in food are destroyed. The lipid transfer proteins (in peanuts, lupins, celery and other vegetables, fruits, and nuts) are highly resistant to heat and digestion, as are the storage proteins (especially relevant in peanuts). Thus, there are people with allergies who suffer from severe allergic reactions even to cooked foods. These proteins are certainly "active" even after heating above 100°C and are mainly responsible for very severe, life-threatening allergic reactions (anaphylaxis). However, even in the case of heat-labile proteins (almost all fruits and vegetables and in nuts), it is not certain at which temperature the allergens become "ineffective". If for example hazelnuts are roasted at 140°C for 40 minutes, they still cause allergic reactions in five out of 17 people with a hazelnut allergy.

In principle, almost all foods have structures that can trigger allergies. However, only the 14 most common food allergens are subject to declaration. Since all 14 allergens are used in the dining halls and cafeterias of the Studierendenwerk Thüringen, no cross-contamination can be completely avoided. The Studierendenwerk Thüringen deliberately does not sell "allergen-free" food for the safety of its guests.

All products arriving in the dining halls and cafeterias via the purchasing and receiving departments must already be properly declared by the manufacturing company. This declaration is recorded in internal documentation systems and thus enables the correct declaration of the food recipes. These recipes must be strictly adhered to during food production. Furthermore, all kitchen personnel are trained to maintain personal hygiene and regular hygiene standards, which must be observed before, between and after each work step. Nevertheless, with all these measures, unintentional cross-contamination can never be completely excluded.

The employees who handle product purchasing are responsible for ensuring that products entering the company from outside are declared regarding the 14 allergens and that they are informed immediately by the manufacturing company or supplier in the event of changes to the recipes. This product declaration is the basis for the declaration of all existing food recipes. Both warehouse employees and kitchen staff are instructed to ensure correct allergen labelling by covering, storing separately, preparing, and cooking food, and adhering to recipes and hygiene regulations. To detect sources of error and ensure compliance with the specifications, all processes are regularly checked.

In principle, the rules of First Aid also apply to acute allergic reactions. It is important that every employee in the company is aware of a central telephone number where medical emergency staff can be called.

All employees in the departments and groups in question are trained in detail with reference to the current Food Information Regulations No. 1169/2011. In addition, they are provided with literature to refresh their knowledge in addition to regular training programs. All employees have also been instructed that compliance with all hygiene regulations and targeted organization in kitchen operations will prevent cross-contamination to the maximum extent possible.

The aim of the Allergen Labelling Regulations is to inform people with allergies which of the 14 allergens subject to declaration are contained in the food before any purchasing decision is made and without the need for additional inquiries. The guests have various possibilities (Internet, notices) to have a look at the menus to inform themselves in advance.

Beverages containing more than 150 mg of caffeine per litre must be labelled "Increased caffeine content. Not recommended for children and pregnant or breastfeeding women". Coffee, tea, or beverages based on coffee or tea extract with the term "coffee" or "tea" in the name are not subject to this regulation. This labelling obligation also applies to other food products containing added caffeine.

Quinine is used as a flavouring in beverages such as tonics and bitter lemonade. Because of their slightly bitter taste, quinine-containing beverages are popular thirst quenchers enjoyed in large quantities, especially during the summer months. However, consumption of larger quantities can be hazardous to individual health. For this reason, beverages containing quinine are labelled with the words "containing quinine".

Baked goods are often coated with fat glaze containing cocoa. Since this can easily be mistaken for chocolate, the use of cocoa-containing fat glaze must be labelled so that the consumer is not deceived.