COLLECTING THE SAP

Sap flow in maple trees will not occur every day throughout the tapping season. It occurs when a rapid warming trend in early to midmorning follows a cool (below freezing) night. Thus, the amount of sap produced varies from day to day. Normally, a single tap-hole produces from a quart to a gallon of sap per flow period (from a few hours to a day or more), with a seasonal accumulation of 10 to 12 gallons per tap-hole likely.

To produce high quality syrup, sap collections should be made as required, not exceeding every two or three days. If this is not possible, collections obtained from prolonged flow periods should be stored and processed separately. During periods of rather low temperatures and under favorable storage conditions, sap may be kept four or five days without reducing syrup quality.

The amount of sap required to produce a gallon of maple syrup varies, depending on its sugar concentration. Sap averages approximately 2 percent sugar. At this concentration, 43 gallons of sap are required to produce 1 gallon of syrup. If the sap contains a higher sugar concentration, less sap will be required
Producing maple syrup is essentially a matter of concentrating the sugar solution to a predetermined level through evaporation. Heat is used to concentrate the sap and to develop the characteristic maple color and flavor that make maple syrup so highly desirable.

In large commercial operations, a continuous feed evaporation process is used. That is, the evaporation pan is arranged so that sap may be continuously added and syrup drawn off. In smaller operations, a "batch" approach is used. The evaporation pan is filled with sap and sap is added as necessary to replace that lost by evaporation. When a suitable amount of concentrated sap is present, the pan is "finished-off" to produce syrup of the correct density.
To begin evaporation, fill the evaporating container (preferably a large shallow pan) with sap. Begin heating the sap to the boiling point, taking care not to burn or scorch the sap. (A Teflon-coated pan is ideal.) As evaporation lowers the level of sap in the pan, add more sap. Continue this process until most of the sap in the pan is highly concentrated and the boiling point of the sap begins to rise above the boiling point of water.

Throughout this process, it may be necessary occasionally to skim the surface of the boiling liquid to remove surface foam and other materials. Finished syrup boils at 7 degrees above the boiling point of water. As the temperature of the boiling sap approaches this point, boiling should be carefully controlled to prevent burning and overheating.

Once the desired boiling point has been reached, the syrup is ready for filtering and packaging. Hot syrup should be filtered through a suitable filter of wool or orlon to remove suspended particles, such as sugar sand, and improve the appearance of the syrup. After filtering, the syrup should be packaged, also while hot. A temperature of at least 180 degrees F is necessary to prevent spoiling while in storage.