Sodium benzoate

Sodium benzoate has the <a href="http://en.wikipedia.org/wiki/Chemical_formula" title="Chemical formula" >chemical formula</a> NaC6H5CO2; it is a widely used <a href="http://en.wikipedia.org/wiki/Food_preservation" title="Food preservation" >food preservative</a>, with <a href="http://en.wikipedia.org/wiki/E_number" title="E number" >E number</a> E211. It is the sodium salt of <a href="http://en.wikipedia.org/wiki/Benzoic_acid" title="Benzoic acid" >benzoic acid</a> and exists in this form when dissolved in <a href="http://en.wikipedia.org/wiki/Water" title="Water" >water</a>. It can be produced by reacting <a href="http://en.wikipedia.org/wiki/Sodium_hydroxide" title="Sodium hydroxide" >sodium hydroxide</a> with <a href="http://en.wikipedia.org/wiki/Benzoic_acid" title="Benzoic acid" >benzoic acid</a>.

Sodium benzoate is a <a href="http://en.wikipedia.org/wiki/Food_preservation" title="Food preservation" >preservative</a>. It is <a href="http://en.wikipedia.org/wiki/Bacteriostatic_agent" title="Bacteriostatic agent" >bacteriostatic</a> and<a href="http://en.wikipedia.org/w/index.php?title=Fungistatic&action=edit&redlink=1" class="new" title="Fungistatic (page does not exist)" >fungistatic</a> under acidic conditions. It is most widely used in acidic foods such as salad dressings (<a href="http://en.wikipedia.org/wiki/Vinegar" title="Vinegar" >vinegar</a>), carbonated drinks (<a href="http://en.wikipedia.org/wiki/Carbonic_acid" title="Carbonic acid" >carbonic acid</a>), jams and fruit juices (<a href="http://en.wikipedia.org/wiki/Citric_acid" title="Citric acid" >citric acid</a>), <a href="http://en.wikipedia.org/wiki/Pickling" title="Pickling" >pickles</a>(<a href="http://en.wikipedia.org/wiki/Vinegar" title="Vinegar" >vinegar</a>), and <a href="http://en.wikipedia.org/wiki/Condiment" title="Condiment" >condiments</a>. It is also used as a preservative in medicines and cosmetics.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-0" >[1]</a><a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-1" >[2]</a> As a food additive, sodium benzoate has the <a href="http://en.wikipedia.org/wiki/E_number" title="E number" >E number</a> E211.

It is also used in <a href="http://en.wikipedia.org/wiki/Fireworks" title="Fireworks" >fireworks</a> as a fuel in <a href="http://en.wikipedia.org/wiki/Whistle_mix" title="Whistle mix" >whistle mix</a>, a powder that emits a whistling noise when compressed into a tube and ignited. The fuel is also one of the fastest burning rocket fuels and provides a lot of thrust and smoke. It does have its downsides: there is a high danger of explosion when the fuel is sharply compressed because of the fuel's sensitivity to impact.

Sodium benzoate is produced by the neutralization of <a href="http://en.wikipedia.org/wiki/Benzoic_acid" title="Benzoic acid" >benzoic acid</a> with sodium hydroxide

.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-Sodium_benzoate_and_Benzoic_acid-2" >[3]</a> Benzoic acid is detectable at low levels in <a href="http://en.wikipedia.org/wiki/Cranberry" title="Cranberry" >cranberries</a>, <a href="http://en.wikipedia.org/wiki/Prune_(fruit)" title="Prune (fruit)" class="mw-redirect" >prunes</a>,

<a href="http://en.wikipedia.org/wiki/Greengage" title="Greengage" >greengage plums</a>, <a href="http://en.wikipedia.org/wiki/Cinnamon" title="Cinnamon" >cinnamon</a>, ripe<a href="http://en.wikipedia.org/wiki/Clove" title="Clove" >cloves</a>, and <a href="http://en.wikipedia.org/wiki/Apple" title="Apple" >apples</a>.

Though benzoic acid is a more effective preservative, sodium benzoate is more commonly used as a food additive because benzoic acid does not dissolve well in water.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-Sodium_benzoate_and_Benzoic_acid-2" >[3]</a>

Concentration as a preservative is limited by the FDA in the U.S. to 0.1% by weight. The International Programme on Chemical Safety found no adverse effects in humans at doses of 647–825 mg/kg of body weight per day.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-3" >[4]</a><a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-4" >[5]</a>

<a href="http://en.wikipedia.org/wiki/Cat" title="Cat" >Cats</a> have a significantly lower tolerance against benzoic acid and its <a href="http://en.wikipedia.org/wiki/Salts" title="Salts" class="mw-redirect" >salts</a> than <a href="http://en.wikipedia.org/wiki/Rat" title="Rat" >rats</a> and <a href="http://en.wikipedia.org/wiki/Mouse" title="Mouse" >mice</a>.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-5" >[6]</a>

Sodium benzoate is, however, allowed as an animal food additive at up to 0.1%, according to <a href="http://en.wikipedia.org/wiki/AFCO" title="AFCO" class="mw-redirect" >AFCO</a>'s[<a href="http://en.wikipedia.org/wiki/Wikipedia:Citing_sources" title="Wikipedia:Citing sources" >specify</a>] official publication.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-6" >[7]</a>

The mechanism starts with the absorption of benzoic acid into the cell. If the <a href="http://en.wikipedia.org/wiki/Intracellular_pH" title="Intracellular pH" >intracellular pH</a> changes to 5 or lower, the <a href="http://en.wikipedia.org/wiki/Fermentation_(food)" title="Fermentation (food)" >anaerobic fermentation</a> of <a href="http://en.wikipedia.org/wiki/Glucose" title="Glucose" >glucose</a> through <a href="http://en.wikipedia.org/wiki/Phosphofructokinase" title="Phosphofructokinase" >phosphofructokinase</a>is decreased by 95%,<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-7" >[8]</a>

thereby inhibiting the growth and survival of micro-organisms that cause food spoilage.

Sodium benzoate is created by adding <a href="http://en.wikipedia.org/wiki/Benzoic_acid" title="Benzoic acid" >benzoic acid</a> to a hot concentrated solution of <a href="http://en.wikipedia.org/wiki/Sodium_carbonate" title="Sodium carbonate" >sodium carbonate</a> until<a href="http://en.wikipedia.org/wiki/Effervescence" title="Effervescence" >effervescence</a> ceases. The solution is then evaporated, cooled and allowed to crystallize or evaporate to dryness, and then granulated.

<h2 >Safety and health</h2>

<div class="rellink relarticle mainarticle" >Main article: <a href="http://en.wikipedia.org/wiki/Benzene_in_soft_drinks" title="Benzene in soft drinks" >Benzene in soft drinks</a></div>

In combination with <a href="http://en.wikipedia.org/wiki/Ascorbic_acid" title="Ascorbic acid" >ascorbic acid</a> (vitamin C, E300),

sodium benzoate and <a href="http://en.wikipedia.org/wiki/Potassium_benzoate" title="Potassium benzoate" >potassium benzoate</a> form <a href="http://en.wikipedia.org/wiki/Benzene" title="Benzene" >benzene</a>, a known <a href="http://en.wikipedia.org/wiki/Carcinogen" title="Carcinogen" >carcinogen</a>.

However, in most beverages that contain both, the benzene levels are below those considered dangerous for consumption.<a href="http://en.wikipedia.org/wiki/Sodium_benzoate#cite_note-8" >[9]</a> Heat, light and shelf life can affect the rate at which benzene is formed.

Professor Peter W. Piper of the <a href="http://en.wikipedia.org/wiki/University_of_Sheffield" title="University of Sheffield" >University of Sheffield</a> claims that sodium benzoate by itself can damage and inactivate vital parts of DNA in a cell's <a href="http://en.wikipedia.org/wiki/Mitochondrion" title="Mitochondrion" >mitochondria</a>. Mitochondria consume oxygen to generate <a href="http://en.wikipedia.org/wiki/Adenosine_triphosphate" title="Adenosine triphosphate" >ATP</a>, the body's energy currency. If they are damaged due to disease, the cell malfunctions and may enter <a href="http://en.wikipedia.org/wiki/Apoptosis" title="Apoptosis" >apoptosis</a>.[<a href="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed" >citation needed</a>]