Lets talk about Maple
Long before European explorers came to North America, the Native Americans had learned how to draw off maple sap and boil it to make sugar. In early spring, they would pierce the tree trunk with a tomahawk, placing a wood chip under the hole to channel the maple water into a bark receptacle. They then boiled the sap in clay containers to obtain maple sugar.
Native Americans used clay pots to boil maple sap over simple fires protected only by a roof of tree branches. This was the first version of the sugar shack. Over the years, this evolved to the point where the sugar shack is not only a place where maple syrup is produced but also a gathering place where a traditional meal can be enjoyed. For the majority of Vermonters, spring would not be spring without a visit to a sugar shack.
Production methods have been streamlined since these early days, but the process remains the same. The sap must first be collected and distilled carefully so that you get the same natural, pure syrup without any chemical agents or preservatives.
In Vermont forests, the maple is considered a valuable tree. It is harvested for its hard, resilient wood and for its sap from which a delicious syrup is obtained.
During the growing season, maples accumulate starch. With the spring thaw, enzymes change this starch into sugar which mixes with the water absorbed through the roots, imparting a slightly sweet taste. While maple water also contains minerals, organic acids and maple taste precursors, water is it's main component (about 97.5%).
Of the six species native to Vermont, Sugar Maple (Acer saccharum) and Red Maple (Acer rubrum) are the most valuable commercially for syrup production.
Maples dominate the majority of Vermont's hardwood forests.
In early spring, maple producers tap their trees on snowshoe. They bore holes 5 cm deep with a drill 1 cm in diameter and drive a spout into the hole. This metal or plastic spout directs the maple sap into a bucket or a system of polyethylene tubes winding in and out of the trees.
Depending on the tree's diameter and strength, it may be fitted with as many as three (3) taps. Trees with trunks less than 25 cm in diameter should not be tapped at all. From mid-march to the beginning of April, alternate freezing and thawing changes the pressure inside the tree and starts the sap flowing.
COLLECTING THE SAP
Traditionally, after the sap was collected in troughs, it was emptied into a large barrel carried on a horse-driven sleigh.
Near the mid-1970s, this technique was gradually replaced by a tubing system, in which a partial vacuum is maintained using a pump. This method of collection, which does not damage the trees, yields more sap and reduces the manpower required. It allows the producer to tap more trees, including those located in rugged terrain.
BOILING THE SAP
Maple sap is transformed into maple syrup in a sugarhouse, or "sugar shack." In this building, the sap is boiled in a large pan, the evaporator. Most of the water (66%) in it evaporates during this process, leaving concentrated maple syrup.
The art of sugaring is centered on the evaporator. From the time the maple sap is poured into the evaporator to the time it turns into syrup, it undergoes a complex chain of chemical reactions which produce the characteristically "maple" color and flavor. Evaporation that is too slow or too fast will affect the color, flavor and texture of the syrup. At sea level, the correct temperature for evaporation is 104ºC. However, since the boiling point varies with altitude, a thermometer must be used to adjust the cooking temperature. For example, in a region where the boiling point of water is 98ºC (or 2ºC below normal), the cooking temperature of the sap must also be reduced by 2ºC (to 102ºC). Almost forty liters of maple sap must be evaporated to produce one liter of syrup. Increasingly, producers use machines that partially concentrate the sap by reverse osmosis, an advanced technique which offers energy savings of 60%, while conserving original maple product characteristics.
Maple syrup must be filtered to remove the impurities that could affect its appearance and flavor. It is important to adjust the density to between 66º and 67º Brix (the Brix unit of measurement indicates the risk of fermentation or crystallization). The syrup is then bottled or put in galvanized metal cans while still very hot (87ºC or more). The heat sterilizes the containers and prevents the formation of mold.
Maple sap is collected in early spring, usually in March and April, when maple trees are in a dormancy state. This sap has only 3 to 5% total solids, consisting mainly of sucrose. Other components are organic acids (mainly malic acid), minerals (mainly potassium and calcium), phenolic compounds (aroma), amino compounds (trace) and vitamins (trace).
From the concentration process of this sap, without any addition, we obtain pure maple syrup. Maple syrup can be declared a good source of 3 essential elements; calcium, iron and thiamin.