Copper

<h4 >Copper</h4>

<p >In classical Western cooking, pots are formed with thick&nbsp;<a href="http://en.wikipedia.org/wiki/Copper" title="Copper" >copper</a>sheets with a thin inner layer of&nbsp;<a href="http://en.wikipedia.org/wiki/Tin" title="Tin" >tin</a>. The copper provides the best thermal conductivity of common metals and therefore results in even&nbsp;<a href="http://en.wikipedia.org/wiki/Heat" title="Heat" >heating</a>. Copper is reactive with acidic foods, discovered with the discovery of tomatoes in the new world and subsequent introduction to old world copper pots. The tin lining prevents the copper from reacting with&nbsp;<a href="http://en.wikipedia.org/wiki/Acid" title="Acid" >acidic</a>&nbsp;foods. The products resulting from the reaction causes&nbsp;<a href="http://en.wikipedia.org/wiki/Copper_toxicity" title="Copper toxicity" >copper toxicity</a>. The lead-free and cadmium-free tin lining is susceptible to&nbsp;<a href="http://en.wikipedia.org/wiki/Tin_pest" title="Tin pest" >tin pest</a>. In some cases unlined copper is desirable, for instance in the preparation of meringues and foams. Copper pots are expensive and require retinning, and when made with thick copper plates are heavy. With modern metallurgical techniques, such as&nbsp;<a href="http://en.wikipedia.org/wiki/Cladding_(metalworking)" title="Cladding (metalworking)" >cladding</a>, copper is incorporated into the constructions of cookware, often as an enclosed heat spreading disk (see below).</p>