The law is very clear on what can be sold as pure maple syrup; only "the liquid derived by concentration and heat treatment of the sap of the maple tree". No processing that "adds or removes naturally occurring soluble materials" is allowed. This does not, however, include the use of approved filter aids for the removal of suspended material such as sugar sand or the use of approved defoamers. Unfortunately, the relatively high price of pure maple syrup can provide an incentive for illegal adulteration with non-maple sugars and/or artificial decolorizing agents. This is quite rare and several analytical methods are available to detect the addition of other types of sugars to maple syrup. Monitoring is conducted by both the maple industry and governmental organizations to detect any illegal products and to remove them from the marketplace. A case from 2011 brought to court by the US Food and Drug Administration when a sample of syrup tested and determined to be 100% cane sugar proves that the laws can and will be enforced.