Xanathan Gum
<p><b >Xanthan gum</b> is a <a href="http://en.wikipedia.org/wiki/Polysaccharide" title="Polysaccharide" >polysaccharide</a>, derived from the bacterial coat of <i ><a href="http://en.wikipedia.org/wiki/Xanthomonas_campestris" title="Xanthomonas campestris" >Xanthomonas campestris</a></i>, used as a <a href="http://en.wikipedia.org/wiki/Food_additive" title="Food additive" >food additive</a> and<a href="http://en.wikipedia.org/wiki/Rheology" title="Rheology" >rheology</a> modifier,<sup id="cite_ref-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-1" >[2]</a></sup> commonly used as a food thickening agent (in salad dressings, for example) and a stabilizer (in cosmetic products, for example, to prevent ingredients from separating). </p>
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It is produced by the <a href="http://en.wikipedia.org/wiki/Fermentation_(biochemistry)" title="Fermentation (biochemistry)" >fermentation</a> of <a href="http://en.wikipedia.org/wiki/Glucose" title="Glucose" >glucose</a>, <a href="http://en.wikipedia.org/wiki/Sucrose" title="Sucrose" >sucrose</a>, or <a href="http://en.wikipedia.org/wiki/Lactose" title="Lactose" >lactose</a>by the <i ><a href="http://en.wikipedia.org/wiki/Xanthomonas_campestris" title="Xanthomonas campestris" >Xanthomonas campestris</a></i> <a href="http://en.wikipedia.org/wiki/Bacterium" title="Bacterium" class="mw-redirect" >bacterium</a>. After a fermentation period, the polysaccharide is precipitated from a growth medium with <a href="http://en.wikipedia.org/wiki/Isopropyl_alcohol" title="Isopropyl alcohol" >isopropyl alcohol</a>, dried, and ground into a fine powder. Later, it is added to a liquid medium to form the gum.<sup id="cite_ref-cohan1_2-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-cohan1-2" >[3]</a></sup></p>
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In the <a href="http://en.wikipedia.org/wiki/Oil_industry" title="Oil industry" class="mw-redirect" >oil industry</a>, xanthan gum is used in large quantities, usually to thicken <a href="http://en.wikipedia.org/wiki/Drilling_mud" title="Drilling mud" class="mw-redirect" >drilling mud</a>. These fluids serve to carry the solids cut by the drilling bit back to the surface. Xanthan gum provides great "low end" <a href="http://en.wikipedia.org/wiki/Rheology" title="Rheology" >rheology</a>. When the circulation stops, the solids still remain suspended in the drilling fluid. The widespread use of <a href="http://en.wikipedia.org/wiki/Horizontal_drilling" title="Horizontal drilling" class="mw-redirect" >horizontal drilling</a> and the demand for good control of drilled solids has led to its expanded use. It has also been added to <a href="http://en.wikipedia.org/wiki/Concrete" title="Concrete" >concrete</a> poured underwater, to increase its <a href="http://en.wikipedia.org/wiki/Viscosity" title="Viscosity" >viscosity</a> and prevent <a href="http://en.wikipedia.org/wiki/Washout" title="Washout" >washout</a>.</p>
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Evaluation of workers exposed to xanthan gum dust found evidence of a link to respiratory symptoms.<sup id="cite_ref-Sargent-1990_6-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-Sargent-1990-6" >[7]</a></sup></p>
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On May 20, 2011 the FDA issued a press release about SimplyThick, a food-thickening additive containing xanthan gum as the active ingredient, warning "parents, caregivers and health care providers not to feed SimplyThick, a thickening product, to premature infants."<sup id="cite_ref-7" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-7" >[8]</a></sup> The concern is that the product may cause <a href="http://en.wikipedia.org/wiki/Necrotizing_enterocolitis" title="Necrotizing enterocolitis" >necrotizing enterocolitis</a> (i.e., NEC). As of July 10, 2012 the FDA has not established the causal link between SimplyThick and NEC.</p>
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Xanthan gum may be derived from a variety of source products that are themselves common <a href="http://en.wikipedia.org/wiki/Allergen" title="Allergen" >allergens</a>, such as corn, wheat, dairy, or soy. As such, persons with known sensitivities or allergies to food products are advised to avoid foods including generic xanthan gum or first determine the source for the xanthan gum before consuming the food.</p>
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Specifically, an allergic response may be triggered in people sensitive to the growth medium, usually corn, soy, or wheat.<sup id="cite_ref-cohan1_2-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-cohan1-2" >[3]</a></sup><sup id="cite_ref-allallergy1_8-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-allallergy1-8" >[9]</a></sup> For example, residual wheat gluten has been detected on xanthan gum made using wheat.<sup id="cite_ref-allallergy1_8-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-allallergy1-8" >[9]</a></sup> This may trigger a response in people highly sensitive to gluten. Some consider this to be a separate allergy to xanthan gum with similar symptoms to gluten allergy. Xanthan gum is a "highly efficient laxative", according to a study that fed 15g/day for 10 days to 18 normal volunteers.<sup id="cite_ref-Daly-1993_9-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-Daly-1993-9" >[10]</a></sup> Some people react to much smaller amounts of xanthan gum, with symptoms of intestinal bloating and diarrhea.<sup id="cite_ref-cohan1_2-2" class="reference" ><a href="http://en.wikipedia.org/wiki/Xanthan_gum#cite_note-cohan1-2" >[3]</a></sup></p>
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