Transcript food additives

food additives
Outline
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food additives
Direct Food Additives
Indirect Food Additives
Types of additives
roles and functions of food additives in food
Coding of food additives
Food safty (food additives)
Food preservation
food additives
Food additives are substances added to products
to perform specific technological functions.
These functions include preserving, i.e.
increasing shelf-life or inhibiting the growth of
pathogens, or adding colouring and flavouring
to food forinterest and variety.
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• are chemical substances added to foods to improve
flavour, texture, colour, appearance and
consistency, or as preservatives during
manufacturing or processing. Herbs, spices, hops,
salt, yeast, water, air and protein hydrolysates are
excluded from this definition.
• There are over 300 permitted additives that can
be used in the UK. Flavourings are not included
in this figure, as there are over 3,000 flavouring
components in UK use, in many different
combinations. International organisations
provide advice on the safety of flavourings
• Includes any substance intended
for use in producing, manufacturing,
processing,preparing, treating,
packaging, transporting or holding
food, and any source of radiation
intended for such use.
• 4 direct food additives = 93% of total
– Sucrose, salt,
corn syrup, dextrose
Food Additive
• A substance which may, by its intended use,
become a component of food, either directly or
indirectly, or which may otherwise affect the
characteristics of food.
– Includes any substance intended
for use in producing, manufacturing,
processing, preparing, treating,
packaging, transporting or holding
food, and any source of radiation
intended for such use.
Direct Food Additives
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Anti-caking agents
Antimicrobial agents
Antioxidants
Colours
Curing and pickling agents
Emulsifiers
Enzymes
Firming agents
Flavour enhancers
Flavouring agents
Humectants
Leavening agents
Release agents
Non-nutritive sweeteners
• Nutrient supplements
• Nutritive sweeteners
• Oxidizing and reducing
agents
• pH control agents
• Propellants and gases
• Sequestrants
• Solvents and vehicles
• Stabilizers and thickeners
• Surface-active agents
Texturizers
Indirect Food Additives
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Processing Aids
Food Contact Materials
Packaging Materials
Cleaning Agents
Ion-exchange resins, filter aids
Enzyme preparations
Microorganisms
Solvents, lubricants, release agents
Specific function additives
Utensils
Working surfaces
Equipment
Metal, plastic, paper, wood, etc.
Detergents
Sanitizers
Direct food additives serve four major
purposes in our foods
To provide nutrition – to improve or maintain the
nutritional quality of food. For
example, the addition of iodine to salt has
contributed to the virtual elimination of simple
goiter. The addition of Vitamin D to milk and other
dairy products has accomplished the
same thing with respect to rickets. Niacin in bread,
cornmeal and cereals has helped
eliminate pellagra, a disease characterized by
central nervous system and skin disorders
To maintain product quality and freshness –
fresh foods do not stay that way for long
periods of time; they rapidly deteriorate, turn
rancid and spoil. Food additives delay
significantly this deterioration and prevent
spoilage caused by growth of microorganisms,
bacteria and yeast and also by oxidation (oxygen
in air coming into contact with the
foods). For example, if you were to cut slices of
fresh fruits such as apples, bananas or
pears, they would rapidly turn brown as a result
of this oxidation process
To aid in the processing and preparation of foods –
additives impart and/or maintain
certain desirable qualities associated with various
foods. For example, we expect salad
dressings to stay mixed once they have been
shaken.
Emulsifiers such as lecithin from soybeans maintain
mixture and improve texture in dressings and other
foods.
They are used in ice cream where smoothness is
desired
Leaveners used to make breads, biscuits and rolls
yeast, baking powder and baking rise, include
soda .
To make foods appealing – the majority of food
additives are most often used for this
purpose. Unless foods look appetizing and
appeal to our senses, they will most likely go
uneaten and valuable nutrients will be lost.
Food additives such as flavoring agents and
enhancers, coloring agents and sweeteners are
included by food processors because we
demand foods that look and taste good.
Types of additives
Additives may be:
• natural – found naturally, such as extracts from
beetroot juice (E162), used as a colouring agent;
• manmade versions – synthetic identical copies of
substances found naturally, such as benzoic acid
(E210), used as a preservative;
• artificial – produced synthetically and not found
naturally, such as nisin (E234), used as a preservative in
some dairy products and in semolina and tapioca
puddings.
Six Categories of Food Additives
• Texture
– Emulsifiers
– Stabilizers
• Miscellaneous
– Enzymes
– Catalysts
– Solvents
– Propellants
• Preservatives
– Antimcrobial
– Antibrowning
– Antioxidant
• Nutritional
– Vitamins/minerals
• Flavor
– Flavor enhancers
– Sweeteners
– Nat/syn flavors
• Color
roles and functions of food
additives in food
. Preservatives
Preservatives aim to:
• prevent the growth of micro-organisms which
could cause food spoilage and lead to food
poisoning
• extend the shelf-life of products, so that they
can be distributed and sold to the consumer with
a longer shelf-life.
For example, bacon, ham, corned beef and other
‘cured’ meats are often treated with nitrite and
nitrate (E249 to E252) during the curing process
Antioxidants
Antioxidants aim to:
• prevent food containing fat or oil from going rancid
due to oxidation, i.e. developing an unpleasant odour
or flavour;
• prevent the browning of cut fruit, vegetables and
fruit juices (and so increase shelf life and appearance).
For example, vitamin C, also known as ascorbic
acid, or E300, is one of the most widely used
antioxidants
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Colours
Colours aim to:
• restore colour lost during processing or storage, e.g.
marrowfat peas;
• ensure that each batch produced is identical
in appearance or does not appear ‘off’;
• reinforces colour already in foods, e.g. enhance
the yellowness of a custard;
• give colour to foods which otherwise would be colourless
(e.g. soft drinks) and so make them more attractive.
Colours
Certain combinations of the following articifical food
colours: sunset yellow (E110), quinoline yellow (E104),
carmoisine (E122), allura red (E129), tartrazine (E102)
and ponceau 4R (E124) have been linked to a negative
effect on children’s behaviour.
These colours are used in soft drinks,
sweets and ice cream.
The Food Standards Agency suggest if signs of
hyperactivity or Attention Deficit Hyperactivity Disorder
are seen in a child, these additives should be avoided.
attention deficit hyperactivity disorder
In 2003, approximately 4.4 million children aged 4-17 years were reported to have a history of ADHD
diagnosis; of these, 2.5 million (56%) were
reported to be taking medication for the disorder
Some studies have linked some food additives to
hyperactivity in children. A recent British study
found that children
without a history of any hyperactive disorder
showed varying degrees of hyperactivity after
consuming fruit drinks
with various levels of additives. Among those that
were studied were: Sodium benzoate (E211),
Tartrazine (E102),
quinoline yellow (E104), Sunset yellow (E110),
Carmosine (E122), Allura red (E129).
Flavour enhancers
Flavour enhancers bring out the flavour in foods without
imparting a flavour of their own, e.g. monosodium
glutamate (E612) is added to processed foods. For
example some soups, sauces and sausages.
Flavourings, on the other hand, are added to a wide
range of foods, usually in small amounts to give a
particular taste. These do not have E numbers because
they are controlled by different food laws. Ingredients
lists will say if flavourings have been used, but
individual flavourings might not be named
Sweeteners
Sweeteners include:
• intense sweeteners, e.g. saccharin, have a sweetness
many times that of sugar and therefore are used in small
amounts, e.g. in diet foods, soft drinks, sweetening tablets;
• bulk sweeteners, e.g. sorbitol, have a similar sweetness to
sugar and are used at similar levels.
If concentrated cordial drinks that contain sweeteners are
given to children between the ages of 6 months to 4 years,
it is important to dilute them more than for adults. Infants
under 6 months should not be given cordial drinks.
Acids, bases and buffers
Acids, bases and buffers control the acidity or •
alkalinity of food, for safety and stability of
flavour
• Anti-caking agents
• Anti-caking agents ensure free movement or
flow of particles, e.g. in dried milk or table salt
Anti – foaming agents
Anti-foaming agents prevent or •
disperse frothing, e.g. in the
production of fruit juices
Glazing agents
Glazing agents provide a protective coating or
sheen on the surface of foods, e.g.
confectionary (for appearance and shelf-life).
Emulsifiers, stabilisers, gelling agents
and thickeners
• Emulsifiers help mix ingredients together that would
normally separate, e.g. Lecithins (E322).
• Stabilisers prevent ingredients from separating again,
e.g. locust bean gum (E410).
• Emulsifers and stabilisers give food a consistent texture,
e.g. they can be found in low-fat spreads.
• Gelling agents are used to change the consistency of a
food, e.g. pectin (E440), which is used to make jam.
• Thickeners help give food body, e.g. can be found in
most sauces.
Coding of food additives
The food additive coding system was developed
by the European Community (EC). The
European food additive code numbers are
prefixed by 'E' (e.g. E223). These E-numbers
indicate the food additives that are approved
for use in Europe
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100-199 food colors
200-299 preservatives
300-399 antioxidants, phosphates, and complexing agents
400-499 thickeners, gelling agents, phosphates,
humectants, emulsifiers
500-599 salts and related compounds
600-699 flavor enhancers
700-899 not used for food additives (used for feed
additives)
900-999 surface coating agents, gases, sweeteners
1000-1399 miscellaneous additive
1400-1499 starch derivatives
Food safty
Two major groups of food sensitivity are known as
food allergy and food intolerance. Food allergies
are abnormal immunologic responses to a
particular food or food component. In contrast,
food intolerances are non-immunologic
responses. Generally, total avoidance of the
culprit food is necessary for true food allergies.
Food intolerances can be managed by limiting the
amount of the food or food ingredient that is
eaten. Total avoidance is usually not necessary for
food intolerances.
Aspartame
Aspartame (951) is an artificial sweetener that is
used to replace sugars in foods and beverages. The
long term effects of aspartame on health have
been studied intensively, but results were
inconclusive. It is noted that aspartame induces
carcinogenic effects in a dose-related manner.
Contradictory results were shown in studies which
reported that aspartame consumption in foods
or other and beverages does not raise the risk of
cancers
The acceptable daily intake (ADI) of aspartame is
currently 50 mg/kg body weight in the United
States
Benzoate
Sodium benzoate (211) is used as a food colouring and
preservative in foods. Children who consumed a
mixture of food colourings and preservatives from soft
drinks and confectionery at high levels were found to
be more hyperactive than those who did not have the
colourings and preservatives
Monosodium glutamate (MSG
is often added to food as a flavour enhancer •
but it can also occur naturally in food. In the
safety assessment conducted by has been
implicated as the causative agent of Chinese
restaurant syndrome (CRS) and asthmatic
attacks
Nitrates
Nitrates or nitrites are added as a preservative,
antimicrobial agent or colour fixative to
processed foods such as meats and cheese.
Nitrate also occurs naturally in water,
vegetables and plants. The human body
converts nitrate in food into nitrite. Nitrite has
been implicated in a variety of long term
health effects, including gastric cancer
Sulphite
Sulphite sensitivity is a food intolerant reaction .
Sulphite has many functions, including as a
antimicrobial agent. It inhibits enzymatic and
nonenzymatic browning, whitens foods, and
serves as a dough conditioner. Manifestations
of sulphite sensitivity include anaphylaxis and
asthma.
Tartrazine
Tartrazine (102) is an approved artificial food
colour. Tartrazine has been implicated in the
aggravation of both asthma and chronic
urticaria in some people