Boiling the sap

Here is our primitive evaporator.  It consists of a stock-watering tank with one end cut out of it, a simple galvanized steel pan about 7 feet long by 2 1/2 feet wide, and a smoke stack.  Under the pan we build a fire from dead trees we cut in the woods.

Our pan will hold about 60 gallons of sap at a time.  Sometimes we fill it once and boil that down to a small batch of about 2 gallons of syrup.  But if the sap is running fast, we may continue adding sap to the pan, eventually boiling down 100 to 150 gallons of sap into one larger batch of 3-5 gallons of syrup.  Most years we make about 20 gallons of pure maple syrup.  We have never sold our syrup.  We enjoy using it ourselves, and giving it away to family and friends.

With our set-up, we can boil off about 10 gallons of water per hour.  For you non-physicists, the boiling process removes only the water.  All the sugar in the sap stays in the pan until almost no water and all the sugar is left.  We call this Pure Maple Syrup.  No additives.  No preservatives.  Nothing but maple sap boiled down to concentrate the sugar.

Here we are using a window screen to skim the impure foam off the boiling sap.