Maple sap, what's in it? Maple sap is a dilute solution of mainly water (95-99%) and sugar (1-5%), along with trace amounts of other substances, including: organic acids, free amino acids, protein, minerals, and phenolic compounds. Sap coming directly from the tree looks like water, and has only a slight sweet taste. Most of the sugar in maple sap is sucrose (which chemically is the same as table sugar), with only very small amounts of other sugars present. It is important to note that maple sap is not just dilute maple syrup. It's fundamentally a different product and only the heat of an evaporator can cause the color and flavor that makes maple syrup what it is.