The Amount of Sugar in Maple Sap.
Maple sap is a nearly colorless liquid composed of water, sugar and various mineral substances, such as lime, potash, magnesia, and iron; it also contains some organic matter in the form of vegetable acids. The peculiar flavor of maple sugar comes, not from the sugar, but from some one or a combination of all the other substances contained in the sap.
The amount of sugar in the sap of the average sugar maple tree varies greatly, the percentage changing in each tree as the season progresses. Careful experiments have shown that the sap contains on an average about 3 percent of sugar. The maximum is reported at 10.2 percent, which was found in a small flow of sap from a sugar maple near the end of a season, during which the tree averaged 5.01 percent.