Maple syrup is highly, highly concentrated sap. The sap itself is mostly 99%+ water, with just a slight sweetness to it. To make syrup, you have to boil away al

Maple syrup is highly, highly concentrated sap. The sap itself is mostly 99%+ water, with just a slight sweetness to it. To make syrup, you have to boil away almost all of that water, going from gallons of sap to only a small amount of syrup. That boiling process and amount of sap required is partly why it's so expensive. It's like aged whisky: you lose so much of what you started with.