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Safe food


When is a substance harmful?

The level in which a substance is harmful depends on the dosage people receive. Too much salt, Vitamin A or even too much water can be harmful. Not because the substance is harmful by nature, but because our body can’t process the quantity. There aren’t any substances that are harmful by nature, only harmful quantities of substances. Most substances will not be harmful and might well even be useful in smaller quantities, but in a higher dosage they might well dangerous for our health

When people have an appetite these days they , open the fridge door, take something out of the cabinet, go into a shop or walk into a restaurant. A good food provision is very normal in our age of time

No one thinks about where all this food in these large quantities and qualities comes from. People know even littler about what has happened to this food in the mean times. A long time ago everyone was involves in some way with the production of food, not only as a consumer but also as a producer.

The care for food provision lies with a small proportion of the population that works in agriculture, aquaculture, fishery industry, food manufacturers and the trade. Economic changes in the society and the growth of the population have caused an gradual but spectacular specialization.

Those developments have contributed to the fact that the distance between food producers and consumers has increased. The use of additives when producing a large number of products has become necessary due to this. The use of additives is not something recent. Salt herbs, spices have been used for a long time to extend the shelf life of meat and fish. In the old days only natural substances were used whereas now also synthetic and nature identical substances are used. The modern food industry makes use of additives to be able to maintain the food assortment in a responsible way

Natural and chemical

Many people see nature and chemistry two opposites. Chemistry is the enemy of nature in their eyes. Ii is therefore important to understand that plants, animals, their surroundings and of course also human beings are built up from chemical substances such as proteins, minerals and a lot more. Our food is also built up from those chemical substances. For the storage, preparation and digestion of food in our bodies chemical processes are indispensable. The contrast between chemistry and nature is therefore not so big as it might seem at first.

All harmful substances in nature are chemical substances; with this we mean to say that they can be distinguished from each other in a chemical way. The chemical industry also produces new substances that are not known in nature. When talking about harmful substances for human beings there is no need to make a distinction between chemical and natural substances. It is all about how those substances get into the food and how you can take that into account


Additives are substances that are added to food deliberately to achieve a certain result with the preparation of the food. You can think of characteristics such as appearance, colour, odour, shelf life and flavour.

There are natural and synthetic additives that are present in “treated” foodstuffs. The use of additives has strongly increased in  industrially produced food or dishes

Examples of natural additives are:

  • Pectin from fruit, that is used as gelling agent in jams and other fruit products
  • Carotene, the orange colorant from carrots, that is used to colour lemonade or butter

Synthetic or artificial additives can be divided into two groups:

A group of substances that is identical to the natural substances or nature identical. Potassium nitrate, the synthetic double for saltpeter,  is a good example. This substance is used to preserve ham or bacon
A group of substances, that is not present in nature, but is manufactured synthetically. The sweetener saccharin that is used in sweetener tablets and in other products for diabetics is an example

“Harmfulness”  of additives 

The level of harmfulness of additives is determined in a way that is used for all substances; by animal testing. The combination of additives and other food ingredients can never be researched on all risks. When additives are finally allowed there is always a safety margin taken into account. It is therefore very likely to have damages to health caused by additives


Environmental contaminants

The quality of the environment is linked to the quality of our food. Food is produced based on the ingredients that the agricultural industry and fishery deliver. These sectors of industry are dependant on the quality of the air, water and soil. Food can absorb harmful substances from the environment when the environment isn’t clean enough. These harmful substances can be broken down or it might not be possible to break them down.
In the first case the substance might be broken down by the influence of light, air, water, other substances or bacteria into substances that are less harmful or not harmful at all
In the second case the substance is persistent, that means to say inviolable. When this substance comes into the food chain it can be dangerous for the public health

We distinct environmental contaminants in;

1.         Heavy metals such as mercury, lead, cadmium, and arsenic
Heavy metals can bottle up in food chains which leads to toxicological  (poisonous) risks for human beings
The tissue of fish and shellfish can contain mercury and arsenic for example

  • Nitrate and Nitrite

Nitrate is nutrient for plants. By over excessive use of fertilizers in the agricultural sector, high nitrate concentrations are found mainly in leafy vegetables. Nitrate is not toxic but when it is stored in the human body nitrate can be formed which is a toxic substance
3.         Polychlorinated biphenyls (PCBs)
            These substances can bottle up in fat tissue of animal origin. Fish that have a high fat content such as eal from strongly contaminated water can contain a high PCB content. Consuming products that contain PCB’s frequently can have a toxic effect on human beings

  • Polycyclic aromatic hydrocarbons (PAHs)

These substances form mainly when grilling, roasting and/or smoking meat or fish and when roasting coffee. Just think of the blackened piece of poultry from the barbeque. With a proper smoke- or roasting technique you can prevent these substances from forming during the preparation of food

  • Mycotoxins

These poisons can form when plant products are mouldy or blemished by the substance aflatoxin which is present on mouldy peanuts. Another toxic which is similar too this one, aflatoxin M1, can be present on grains

  • Radiocative particles

Radiocative particles can come into the environment by rain mainly due to explosions and the waste of nuclear power plants

Residues of pesticides

The agricultural industry makes use of pesticides. These substances used against insects are called insecticides, against moulds and fungus fungicides are used, and against weeds herbicides are used, against rodents rodenticides are used. Residues of these substances can be harmful

Residues of medicines for animals

These substances are used to prevent and treat illness in animals. Also substances that contribute to the growth of animals belong in this group. Harmful residues of these substances can be found in the animal’s tissue.

Residues of packaging materials
Glass, tin, cardboard, wood, paper and numerous plastics are used as packaging for food. Some substances, especially those in plastics, can cause chemical reactions with food. Substances that get into food this way are called migration residues. The compound of which the plastics are built up from, transfer easily, especially to food that contains a lot of fat or oil. Some of these substances are carcinogens (can cause cancer). The food authority therefore has guidelines on the composition and characteristics of plastics that are used to make cling film, margarine tubs and the inside layers of milk cartons.

In the near future you can expect that the chef has to ask the supplier for proof of the absence of contaminants in the products that are delivered by him. With the liability laws these days it is important to be able to give your customers certainty about this. The government has formed legal guidelines to reduce the use of additives that contaminate food and to lower the residue levels

Harmful substances that are present in food naturally

In most products from vegetable origin a small level of harmful substances is naturally present. With a normal diet you will not notice anything from this. At the moment we know more than 10.000 substances from a vegetable origin. Hundreds of those can be harmful if we consume too much of them. Those substances vary from nicotine in tobacco to the substance cannabinol found in marihuana, from Hydrogen cyanide in bitter almonds to oxalic acid in rhubarb, purslane and beets, and from solanine in the green parts of the potatoe to tannic acid in tea.

Some examples;
Oxalic acid is naturally present in a number of green vegetables. This substance forms a compound with calcium from dairy products for example and shuts them down. Calcium and oxalic acid form a compound that cannot be taken up by the body.
Fasine is a substance that contains proteins in pulses that can clot up red blood cells or can obstruct digestion. These toxic substances lose their effect when those pulses are heated

Harmful contaminants that are present during treatment and preparation of food

Decay and contamination by micro organisms
Bacteria, yeasts and moulds are micro organisms that are present everywhere; in air, water, on the ground, on your hands and on the workbench. Also on food. It depends on the environment if they are able to develop. Just think of blue-green mould on your bread, the contents of a can that has been opened a long time ago or the taste of milk that has gone sour.
We know bacteria with well known names such as salmonella, campylobacter and listeria that can cause illness when they sufficiently present in the intestines or are able to reproduce there.
Micro organisms can also disgorge toxic substances when they are present in sufficient numbers in food. That toxic substance will symptoms of illness

Safety in the kitchen

In every kitchen and on all the food micro organisms are present. From what you have read above  it may be clear that it is very important to prevent decay of food or food poisoning in the kitchen. The biggest risks in the kitchen are not those of the quality of the ingredients that are delivered or the materials and preparation methods, but in an unhygienic treatment and storage of food. This will be pointed out in every topic that is discussed on this website. A number of classics are:

  • Wash hands regularly
  • Treat foods with your hands as little as possible. When you have touched raw meat, fish or poultry, you hands are contaminated with pathogenic bacteria. What will you do?  Of course, wash your hands!!
  • Do not store cooked and uncooked products together and do not let them have contact
  • Defrost frozen meat or poultry on a rack in the fridge. Rinse away the dripping and clean up spilled dripping with kitchen paper
  • Clean up waste straight away and make sure flies can’t get to the food
  • Clean regularly and properly
  • Store products as is stated on the packaging and use them in the order of purchasing them
  • Check fridges regularly and clean them
  • Heat up food quickly and cool it down quickly

Food additives, overview European E-numbers

The European union and the harmonization of the European market have caused a change in food laws. The countries in the EU used to have all different rules regarding food additives, but since the harmonization of European laws and food laws in 1993, the lists of food additives have been equalized.

Additives can be recognized by their E-number. That “E” that has to be printed on the label means that the additives are approved to use within the EU. Because approved extraction agents don’t have to have E-numbers, we usually say that aromas are mixtures of a large number of substances and modified starches, that are not considered to be official additives. Additives can also only be used to function as colorant or aroma substance.

Additives are classified into groups and numbers based on the goal they have. The European classification that is outlined below can change in the future; new additives can be allowed or they can be taken of the list

E100-E180 Colourants
Colorants are substances that give foodstuff colours. Many products from the food industry are dull and unattractive without  these colours. The food act makes a distinction between colours that can be eaten and colorants that are used to colour the surface of a product. They are used to colour the crust of cheese for example. For colorants that are used to stamp meat , eggs and cheese other rules have been composed.

Often used colorants are:

  • Carotene or, Provitamin A, in cheese, margarine, halvarine, oils and soft drinks
  • Caramel in vinegar, beer, stock and caramel custard
  • Carmine which is used to give the colour red in soft drinks
  • Beet red in tomato ketchup, soft drinks in pin red coloured custard

E200-E252 Preserving agents
Preserved substances are compounds that slow down or prevent decay. They deal with decay that is caused by micro-organisms, bacteria, moulds and yeasts. The preserving agent can be left out when other preserving methods are applied such as  freezing, pasteurizing, pickling, smoking or brining.

Some examples:

  • Benzoic acid and sorbic acid are added to improve the shelf life of shrimps, mustard and mayonnaise
  • Biphenyl. This substance is applied to the outside of citrus fruit and bananas. This substance slows down the growth of moulds and mycotoxins forming
  • Sulfite. This substance can depending on the level of acidity influence the growth of bacteria, yeasts or moulds
  • Sodium nitrite. This is used in meat products such as bacon, ham and sausages to slow down the growth of bacteria and next to that is also gives the product a pink colour

E260-E297 and E322-E385 Acidity regulators
Acidity regulators are substances that can increase or give food a sour taste. They also improve the effect of preserving agents and antioxidants. They are responsible for the preservation of colour and give the product a fresh and sour taste. Many acidity regulators are naturally present in our food

Some examples:

  • Citric acids in desserts, lemonades. Mayonnaise and jams.
  • Acetic acids in meat and salad dressings
  • Lacto acids in sour cream, buttermilk and meat products

E300-E321 Antioxidants

Antioxidants prevent oxidation. Oxidation is a change occurring by the influence of oxygen in the air, like fat getting rancid. Also colour changes might occur, especially in fruit and vegetables. Antioxidants like Vitamin E, are naturally present in oil of plant origin. By heating them they are lost and they are added by the producer afterwards. This is mainly done in fat products

Some example of the use of antioxidants are:

  • Sulfite blocks the enzymatic processes in pre treated vegetables and potatoes that cause brown colouring which makes the product less attractive. Also ascorbic acid or Vitamin C prevents lodd of colour in vegetables, preserved vegetables, meat products and wheat flour.
  • Tocopherol or Vitamin E in edible oils and fats prevent that they go rancid
  • Butylated hydroxytoluene (BHT) in oils and fats prevents decay by oxidation

E400-E418 Thickeners
Thickeners can bind water and make a thin liquid substance thicker. Starch is the most common used thickener from a number of substances from plant origin. Yelling agents are substances that gives food shape by forming a gel and giving the product a jelly structure.

The industry makes use of:

  • Gums, they contain modified starches and thickening agents and cellulose compounds that are used as thickening agents in joint products. They are responsible for a stable consistency in products that are stored for a longer period. They work better than starch products such as wheat flour or potato starch
  • Pectin as gelling agent in jams
  • Gelatin and agar-agar in puddings and desserts

E420-E495 Emulsifiers and Stabilizers
Many additives are emulsifier, stabilizer and thickener at the same time.
Emulsifiers are substances that can mix with oil and with water or can make this mixture possible or maintain it in food. Most emulsifiers are derived from oils and lead to an emulsion.
Stabilizers are substances that make a steady mix of two or more unmixable products possible even when the product is modified after that

Examples are:

  • Lecithin, that is used as emulsifier and antioxidant in ice-cream, margarine, dough products and stock

E500-E529 Acidity regulators
Acidity regulators are substances that can regulate or change the acidity of  a product. Acidity regulators are responsible to keep the acidity of a product within certain levels. They improve the stability, shelf life and safety of a product and are used in ice-cream, meat products and dairy products.

E530-E585 Anti caking agents
Anti caking agents are substances that reduce the tendency that food particles have to clutter up. These additives reduce the strength of  humidity attraction that dry and fine products have
Silicates are responsible for keeping instant coffee, icing sugar, salt and milk powder soluble.

E620-E640 Flavour enhancers
Flavour enhancers are substances that make the existing flavour of a product stronger. Flavour enhancers themselves are without odour and aroma and strengthen the flavour of all aromas present.
Inosinates and glutaminates are categorized to be flavour enhancers. They are mainly used in soups, stocks and meat products. A well known flavour enhancer is Monosodium glutamate, that is an ingredient of the Chinese spice “Ve-tsin”

E900-E914 Improving agent
Improving agents are substances that can be added to dough or meal to improve the baking capacities of them. The rising process will go faster which improves the baking result of bread and cakes. An often used substance is absorbic acid that is also an antioxidant. This additive has a double function.

E920-E948 Packaging gasses
Packaging gasses are gasses that are introduced into the packaging before, after or during packaging, with the exception of oxygen. The food industry uses these gasses to improve the shelf life of certain products.
Nitrogen gas is added to hermetically sealed soups and carbonic acid is added to soft drinks

E950-E976 Sweeteners
Sweeteners are substances that are used as table sweetener or to give food a sweet taste. Sweeteners are chemically produced substances that are much sweeter than sugar. We distinct sweeteners that provide energy and ones that don’t.
Sweeteners are often used in low calorie products as a replacement of sugar in sweet food product such as soft drinks, jams, candy and in diabetic products