Maple syrup concentrated
from the sap of maple trees, is a uniquely American product. It takes
from 30 to 40 gallons of sap (3% sucrose) to produce one gallon of syrup
(65% sucrose), and is only produced for 4 to 6 weeks in the spring when
the sap first begins to flow. Unless labeled "pure maple syrup", a product
is likely to be mixed with corn syrup to cut expense.