Lesson E4 - Food Additives Flashcards
Food additives are
substances that are added to food to improve appearance, texture, and storage
of food. This is the classical definition, but a broader definition would include additives to
improve nutritive value, e.g. vitamins and minerals
Unintentional
additives are those
that are added inadvertently as a result of the growing, manufacturing and
storage processes
These unintentional additives are often termed contaminants and the amount
that is present in food is
limited by regulations
Additives are convenience substances and are not
necessarily required.
The risk/benefit ratio of additives must be carefully determined. The
techniques used to determine risk/benefit is to study the toxicity in animals and then extrapolate
the results to humans. The limitations are:
The risk/benefit ratio of additives must be carefully determined. The
techniques used to determine risk/benefit is to study the toxicity in animals and then extrapolate
the results to humans. The limitations are:
Some of the principles concerning food additives which have been adopted by the World Health
Organization are:
- Use of additives is justified if they enhance or maintain the quality or acceptability of food.
While this statement has merit, it does not address the risk/benefit assessment of the
additive. If the risk is high, then no level of benefit would warrant use of the agent. - Additives should be used only in quantities sufficient to obtain stated ends.
- Additives should be pure. Additives often contain impurities, and in some cases the
toxicity has been associated with the impurity. Thus, toxicological evaluation of the
impurity must be conducted. - Toxicological evaluation of additives should be undertaken. Society has used a number of
additives for centuries. Should these compounds be exempt from toxicological assessment?
If an agent has been used for 200 years, is it necessarily without risk? A reasonable
position would be to gather the available information on a specific compound and utilize that data to determine potential risk and the need for further study. - Special groups should be considered, i.e. those who may be expected to eat a large amount
of a particular substance. Risk assessments are determined on the concept that individuals
exhibit similar behaviour or dietary habits. In other words, we do not eat ten bags of potato
chips each day. Unfortunately, some individuals do eat ten bags of potato chips each day
and the risk assessments must be such as to include these individuals. A good example of
this concept occurred in the early 1970’s. There were a number of deaths due to cardiac
causes in individuals with no apparent risk factors for heart disease. The causative factor
was found to be cobalt chloride, a compound which inhibited the heart muscles from
functioning. Cobalt chloride was added to beer to control the head (foam) on the glass of
beer. Risk assessments determined that individuals would need to consume 24 beers every
day for long periods of time to receive a toxic dose of cobalt chloride. Unfortunately, some
individuals do and some of these succumbed to the effects of cobalt chloride. The agent is
no longer added to beer
Flavouring
This class of additives includes substances such as
spices, flavouring agents, essence of
smoke, synthetic flavours, etc.
Colours
Colouring agents are organic dye stuffs. Most are well evaluated, but one is never sure of
the carcinogenic potential. It is fortunate that colouring agents are used in small amounts as
they may have one of the greatest potentials for toxicity among
food additives
It has been claimed that since food colouring agents can be considered organic dye stuffs
derived from coal tar, and since coal tar is a carcinogen, all artificial food colours are
carcinogens and only colouring agents from natural sources
should be used.
Colours are added to give food an
appetizing appearance;
Texture Agents
This class of agents are added to improve or impart a specific texture to a product. Silicates are added to flour and flour products to keep them free flowing. Emulsifying and
thickening agents (gums, agar, alginates) are added to a number of frozen foods, e.g. ice cream and sherbet. Milk shakes contain a thickening agent.
Preservatives
The use of agents to preserve the quality of food is one of the more rational uses of
additives. It allows the delivery of food to distant destinations and ensures the appropriate
quality of the food for the consumer. In most cases, the benefit outweighs the risk.
Antibacterials:
Historically, sodium chloride was the first preservative used. It is still used today. It is
effective as a
a preservative, especially when coupled with smoking or drying
Smoke is an age-old method of preserving food, mainly meat. It is also used to impart
flavour to food.
Sodium benzoate is added to food as it has antibacterial and fungistatic activity, thus
preventing the spoilage of
food
