From Sap to Syrup: The Making of Maple Sugar

From Sap to Syrup: The Making of Maple Sugar. . , Selecting Trees , Most members of the Maple family produce maple syrup. The favorite of sugarmakers is the Sugar Maple (Acer saccarum), which has a higher level of sugar than others. The Red Maple (Acer rubrum) is quite plentiful in our region and, while lower in sugar content that the Sugar Maple, also produces quality maple syrup. Trees should be 10 to 12 inches in diameter when measured 4.5 feet above ground level before being tapped., Tapping and Collecting , The maple harvest season begins in early spring, when freezing nights, followed by above freezing daytime temperatures, cause the sap to flow. When nights are still cold, water from the soil is absorbed into the tree and warmers temperature create the pressure that pushes it back down to the bottom of the tree, making it easy to collect., Sugarmakers tap the trees to release the sap by drilling small holes into trees and inserting a hollow spike, called a spile. Backyard producers collect the sap in buckets that hang from the spouts. Larger scale operations use plastic tubing and a vacuum pump system that allows the sap to efficiently flow downhill directly into large collecting tanks. The sap is then pumped into storage tanks in the Sugar House., Evaporating Excess Water , Maple sap does not store well and must be reduced to syrup quickly. In its natural state, sap contains 98% water and 2% sugar. While sap can be boiled over flame or stove to reduce water content, larger scale operations use an evaporator., Keystone's Sugar Shack uses a wood-fired evaporator which removes about 35 gallons of water an hour., Sap is boiled to remove water until it reaches 66% sugar content, which is determined using a hydrometer., Finishing syrup at the proper concentration is critical; too high and the syrup will crystallize, too low and it will spoil. Some operations run the sap through a Reverse Osmosis filter which can efficiently remove about 1/2 of the water from the sap, dramatically hastening the boiling time. Once the sap has turned to syrup, it is drawn off of the evaporator into a holding tank., Finishing and Bottling , The Maple Syrup is then sent through a filtering press to remove impurities. Next, it is boiled to kill bacteria, allowed to cool to between 180°F and 200°F, and poured into containers and sealed. This assures sterile, airtight packaging and a long shelf life when unopened.