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ESF Maple Syrup

From the Forest: Introducing Maple Syrup from ESF

Tapped and produced on the 4,000-acre Heiberg Memorial Forest in Tully, N.Y., maple syrup produced by the SUNY College of Environmental Science and Forestry (ESF) debuts this week at the ESF College Bookstore.

Unlike mass-produced syrups that are heavy with artificial flavoring and sweeteners, ESF's syrup is 100 percent pure maple syrup, painstakingly crafted from the sap produced by some 2,000 sugar (and a handful of red) maple trees as part of an ongoing academic demonstration project. These two species produce the sweetest sap of all the maples and, combined with the soils, temperature and overall environment — the equivalent of "terroir" in winemaking — of the Northern Appalachian Plateau, make it possible for the college to produce its unique syrup.

ESF Maple Syrup will be sold in the bookstore, which opened this week on the main level of the college's new Gateway Center, and will soon be available online at www.esf.edu/bookstore. The bookstore is operated by the ESF Alumni Association; proceeds from the sale of maple syrup will help fund scholarships awarded by the association to ESF students. Last year, the association provided $14,500 in scholarships.

Mark Appleby, southern forest property manager for ESF, said there are typically only about 20 prime sap days in a season and they generally begin in late February when temperatures in Central New York begin to climb into the 40s during the day and then dip to below freezing at night. This temperature fluctuation creates pressure inside the maples that naturally forces out the sap.

In mid-February, the Heiberg Forest production team goes into the sugar bush – often on snowshoes – to place one or two taps in each tree depending on its size, said Appleby, who oversees the operation. The staff members strive to make the smallest impact possible on their trees by using a 1/4" bit when tapping. After the harvest is concluded, this opening begins to heal immediately and seals completely in nine to 12 months. Research has shown tapping in this manner does no harm to the trees.

"It takes between 40 and 50 gallons of sap to make a gallon of pure maple syrup and we begin this process the same day the sap is collected so it's as fresh as possible," Appleby said.

A reverse osmosis process, using a semipermeable membrane, is employed to quickly and efficiently remove up to 80 percent of the water contained in the sap and produce a concentrate with the precise sugar content required for the next stage of the process. Using reverse osmosis to remove most of the water is far superior to boiling alone because it protects the delicate sap from prolonged exposure to high heat which can cause burning and excess caramelization. This process is also far more energy efficient.

The concentrate is then transferred to a three-stage evaporator that allows ESF sugar makers to precisely control the temperature and produce an even heat distribution across the finishing and flue pans. This allows them to remove the remaining excess water and produce a maple syrup with a sugar content of precisely 66.0 brix — a measurement that determines the sugar content in a liquid — at the time of barreling. Producing the maple syrup in this way allows the staff to more precisely control the natural carmelization process and craft delicate, light amber syrup.

The hot syrup (218 degrees) is twice-filtered with a special filtering medium and a syrup press to meet stringent purity standards before being pumped into 55-gallon barrels for storage until bottling at a local facility.

"For good measure, we test and sample the maple syrup for consistency when each barrel is one-quarter full and then again when it's topped off and label it with sugar content, color grade and date produced," Appleby said.

ESF's maple syrup artisans complete the process by barreling, testing, sampling and grading the syrup as either light amber, medium amber or dark amber -- each with its own distinct flavor profile. The last step is to send it off for bottling and then to the ESF College Bookstore where it is available for purchase. The bookstore is focusing its sales efforts on members of the ESF college community, as well as colleagues throughout the SUNY system and at nearby Syracuse University.