Chemistry in our life - Scuola Italiana Madrid€¦ · Methodology to preserve food . Food is so...
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Transcript of Chemistry in our life - Scuola Italiana Madrid€¦ · Methodology to preserve food . Food is so...
All food products except the ones growing in your kitchen
garden have food preservatives. Every manufacturer adds food
preservatives to the food during processing. The purpose is generally to avoid spoilage
during the transportation time.
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Why food preservation?
Food Preservation is basically done for three reasons:
To preserve the natural characteristics of food
To preserve the way food looks To increase the shelf value of food for
storage
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Methodology to preserve food
Food is so important for survival, so food preservation is one of the oldest technologies used by human beings to avoid its spoilage. Different ways and means have been found and improved for this purpose.
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Natural Food Preservatives Boiling, freezing and refrigeration, pasteurizing,
dehydrating, smoking, pickling are the traditional few and are considered to be the natural ways of preserving food.
Sugar, salt, alcohol, vinegar are also often used as food preservatives. Sugar and salt are the earliest natural food preservatives that very efficiently drop the growth of bacteria in food. To preserve meat and fish, salt is still used as a natural food preservative.
Coffee powder and soup are dehydrated and freeze-dried for preservation.
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Artificial Preservatives
Nuclear radiation is also being used now as food preservatives.
Modified packaging techniques like
vacuum packing and hypobaric packing also work as food preservatives.
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Chemical Food Preservatives
Chemical food preservatives have also been used for quite some time now.
They seem to be the best and the most effective for a longer shelf life and are generally food proof for the preservation purpose. These food preservatives are the chemical substances that:
stop or delay the growth of bacteria and spoilage keep foods from becoming rancid or developing black spots suppress the reaction when food comes in contact with oxygen,
heat, and some metals prevent the loss of some essential amino-acids and some vitamins enhance the food flavours and colours
These artificial preservatives can be added to the food or sprayed on the
food.
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Antimicrobial agents
Antimicrobial agents: they inhibit the activity of or kill the bacteria, molds, insects and other microorganisms.
Benzoates: Sodium benzoate, Benzoic acid. This group of chemical food preservative has been banned in Russia
because of its role in triggering allergies, asthma and skin rashes. It is also considered to cause brain damage. This food preservative is used in fruit juices, tea, coffee.
Sorbates: such as Sodium sorbate, Potassium sorbate. Nitrites: such as Sodium nitrite, commonly used as preservative for
ham, bacon, sausages and bologna, it gets converted into nitrous acid when consumed and is suspected of inciting stomach cancer. Germany and Norway have banned the use of this harmful food preservative after declaring it a toxin.
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Antioxidants
Antioxidants: that act as free radical scavengers. Vitamin E, Vitamin C, Pine Bark Extract, Grape Seed Extract
and Apple Extract Tea (all these natural) Sulfites Butylated hydroxytoluene (BHT), the common food
preservatives for fruits, dried fruits, canned olives and peppers, corn syrup, cornstarch, wine vinegar, and wine have side effects in form of headaches, joint pain, heart palpitations, allergies, and cancer.
Sodium Erythorbate Sodium Diacetate, Sodium Succinate Sodium Dehydro Acetate Succinic Acid and Ascorbic Acid Parabens Erythorbic Acid Proplyphenols
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Chelating agent
Chelating agent: work on enzymes and disrupt their metabolism leading to the preservation.
Disodium ethylenediaminetetraacetic acid (EDTA),
is one of the most commonly used preservatives for a number of packaged foods, it has multiple negative impacts and associated allergy and reaction cases. Though use in a lot of food products and cosmetics it is known to cause skin allergies and reactions, besides aggravated asthma problems and kidney damage.
Polyphosphates Citric acid Ascorbic acid.
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Food Flavourings
Food Flavourings: Artificial flavouring agents are used for enhancing food flavours. Salad dressings and a lot of other packaged foods use artificial food flavour enhancers.
Monosodium Glutamate (MSG) Disodium Guanylate Disodium Inosinate is one of the most dangerous chemicals to
look out for, as it is often disguised under different names. All three together are quite notorious for their harmful effects. They are known to cause and aggravate problems like kidney stones, nausea, headaches, obesity and burning sensations in the stomach.
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We must read the labels! To regulate the additives, and inform consumers, each additive is
assigned a specific number, termed as "E-number", which is used in Europe for all approved additives. This numbering scheme has now been adopted and extended by the Codex Alimentarius Commission to internationally identify all additives, regardless of whether they are approved for use.
E numbers are all prefixed by "E", but countries outside Europe use only the number, whether the additive is approved in Europe or not. For example, acetic acid is written as E260 on products sold in Europe, but it is simply known as additive 260 in some countries. Additive 103, alkanet, is not approved for use in Europe so it does not have an E-number, although it is approved for use in Australia and New Zealand.
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E-numbers E 100–199 Colours: 100–109 yellows; 110–119 orange; 120–129 reds;
130–139 blues & violets; 140–149 greens; 150–159 browns & blacks;160–199
gold and others E 200–299 Preservatives: 200–209 sorbates; 210–219 benzoates; 220–229
sulphites; 230–239 phenols and formates (methanoates); 240–
259 nitrates; 260–269 acetates (ethanoates); 270–279 lactates;
280–289 propionates (propanoates); 290–299 others
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E-numbers E 300–399 Antioxidants and acidity regulators: 300–305 ascorbates (vitamin C); 306–309
Tocopherol (vitamin E); 310–319 gallates and erythorbates; 320–329 lactates;
330–339 citrates and tartrates; 340–349 phosphates; 350–359 malates and adipates; 360–369
succinates and fumarates; 370–399 others E 400–499 Thickeners, stabilisers and emulsifiers: 400–409 alginates; 410–419 natural gums; 420–429
other natural agents; 430–439 polyoxyethene compounds;
440–449 natural emulsifiers; 450–459 phosphates; 460–469 cellulose compounds; 470–489 fatty acids and compounds; 490–499 others
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E-numbers E 500–599 pH regulators and anti-caking agents: 500–509 mineral acids and bases; 510–519
chlorides and sulphates; 520–529 sulphates and hydroxides;
530–549 alkali metal compounds; 550–559 silicates; 570–579 stearates and gluconates; 580–599 others
E 600–699 Flavour enhancers 620–629 glutamates; 630–639 inosinates; 640–649
others
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E-numbers E 700-799 Antibiotics E 900-999 Miscellaneous 900–909 waxes; 910–919 synthetic glazes; 920–929
improving agents; 930–949 packaging gases; 950–969 sweeteners;
990–999 foaming agents E 1100–1599
Additional chemicals, new chemicals that do not fall into standard classification schemes
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