Potassium benzoate
<p ><b>Potassium benzoate</b> (<b>E212</b>), the <a href="http://en.wikipedia.org/wiki/Potassium" title="Potassium" >potassium</a> <a href="http://en.wikipedia.org/wiki/Salt_(chemistry)" title="Salt (chemistry)" >salt</a> of <a href="http://en.wikipedia.org/wiki/Benzoic_acid" title="Benzoic acid" >benzoic acid</a>, is a food <a href="http://en.wikipedia.org/wiki/Preservative" title="Preservative" >preservative</a> that inhibits the growth of <a href="http://en.wikipedia.org/wiki/Mold" title="Mold" >mold</a>, <a href="http://en.wikipedia.org/wiki/Yeast" title="Yeast" >yeast</a>and some <a href="http://en.wikipedia.org/wiki/Bacterium" title="Bacterium" class="mw-redirect" >bacteria</a>. It works best in low-<a href="http://en.wikipedia.org/wiki/PH" title="PH" >pH</a> products, below 4.5, where it exists as benzoic acid.</p>
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Acidic foods and beverages such as <a href="http://en.wikipedia.org/wiki/Fruit_juice" title="Fruit juice" class="mw-redirect" >fruit juice</a> (<a href="http://en.wikipedia.org/wiki/Citric_acid" title="Citric acid" >citric acid</a>), sparkling drinks (<a href="http://en.wikipedia.org/wiki/Carbonic_acid" title="Carbonic acid" >carbonic acid</a>), <a href="http://en.wikipedia.org/wiki/Soft_drink" title="Soft drink" >soft drinks</a> (<a href="http://en.wikipedia.org/wiki/Phosphoric_acid" title="Phosphoric acid" >phosphoric acid</a>), and <a href="http://en.wikipedia.org/wiki/Pickling" title="Pickling" >pickles</a> (<a href="http://en.wikipedia.org/wiki/Vinegar" title="Vinegar" >vinegar</a>) may be preserved with potassium benzoate. </p>
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It is approved for use in most countries including <a href="http://en.wikipedia.org/wiki/Canada" title="Canada" >Canada</a>, the<a href="http://en.wikipedia.org/wiki/United_States" title="United States" >U.S.</a>, and the <a href="http://en.wikipedia.org/wiki/EU" title="EU" class="mw-redirect" >EU</a>, where it is designated by the <a href="http://en.wikipedia.org/wiki/E_number" title="E number" >E number</a> E212. In the EU, it is not recommended for consumption by children.<sup id="cite_ref-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Potassium_benzoate#cite_note-1" >[2]</a></sup></p>
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Potassium benzoate is also used as the whistle in many <a href="http://en.wikipedia.org/wiki/Fireworks" title="Fireworks" >fireworks</a>.<sup id="cite_ref-2" class="reference" ><a href="http://en.wikipedia.org/wiki/Potassium_benzoate#cite_note-2" >[3]</a></sup>
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One very common way to make potassium benzoate is by oxidizing <a href="http://en.wikipedia.org/wiki/Toluene" title="Toluene" >toluene</a>.<sup id="cite_ref-3" class="reference" ><a href="http://en.wikipedia.org/wiki/Potassium_benzoate#cite_note-3" >[4]</a></sup>
Another way to synthesize potassium benzoate in the lab setting is by reacting <a href="http://en.wikipedia.org/wiki/Methyl_benzoate" title="Methyl benzoate" >methyl benzoate</a> with potassium thioacetate.<sup id="cite_ref-4" class="reference" ><a href="http://en.wikipedia.org/wiki/Potassium_benzoate#cite_note-4" >[5]</a></sup>
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The <a href="http://en.wikipedia.org/wiki/Mechanism_of_action" title="Mechanism of action" >mechanism</a> of food preservation begins 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%.</p>
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In combination with <a href="http://en.wikipedia.org/wiki/Ascorbic_acid" title="Ascorbic acid" >ascorbic acid</a> (vitamin C), <a href="http://en.wikipedia.org/wiki/Sodium_benzoate" title="Sodium benzoate" >sodium</a> and potassium benzoate may 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>. Heat, light and shelf life can affect the rate at which benzene is formed. The <a href="http://en.wikipedia.org/wiki/Food_and_Drug_Administration" title="Food and Drug Administration" >Food and Drug Administration</a> was performing tests in 2006, but the <a href="http://en.wikipedia.org/wiki/Environmental_Working_Group" title="Environmental Working Group" >Environmental Working Group</a> is calling for the FDA to publicly release all tests and use their authority to force companies to reformulate to avoid the potential benzene forming combination.<sup id="cite_ref-5" class="reference" ><a href="http://en.wikipedia.org/wiki/Potassium_benzoate#cite_note-5" >[6]</a></sup><sup id="cite_ref-4" class="reference" ></sup>
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