You may consult the Maple products from Québec website. It has tons of information on the origins of maple syrup as well as its classification guidlines and antioxydant values.
To view the document, click here.
This kind of system has been studied in the past and has shown very low efficiency in removing microbial contamination from the sap. The penetrating power of these wavelenghts is very weak and fails to effectively treat the sap, especially if it's cloudy and contains suspended matters as is usually the case at the end of the season. For these reasons, this type of system is not considered effective for this type of product.