Maple syrup

North American Indian tribes, notably the Angonquins, Iroguois, and Ojibways, extracted the maple tree sap long before Europeans colonized America. To the colonists, maple sugar was chaper than the tax-laden cane sugar. After the Revolution, some Americans preferred maple syrup on the moral ground that it did not require the work of slaves to produce it. Demand for maple syrup, however, declined steeply once cane and beet sugar became cheap. Today the production of maple syrup is almost isolated to the Eastern Candadian provinces and the American Northeast.

Humans make syrup in a process that mimics the bees' production of honey: Extraction of dilute juices from plants and water evaporation to concentrate the sugars. Tree syrups, such as maple syrup, are similar to honey in that the retain nearly all the original contents of the sap and are not further refined like cane sugar. The Acer saccharum maple tree produces the greatest quantity and quality of sap, and accounts for most of the syrup currently produced.

The first step in maple syrup production is the sap run. The sap is collected in the spring between the first major thaw and the burst of leaf buds. Sap production is affected by four external factors: severe winter that freezes the roots; snow cover that keeps the roots cold in the spring; extreme variation in tempreature from day to night; and good exposure to the sun. The Canadian provinces meet all of these conditions favorably. Sap runs in other trees, but maples produce the most due to a unique mechanism by which they force sugars from the previous season out of storage.

Up until the 20th century, sap was collected by punching a small hole in the tree bark, inserting a spout, and hanging a bucket to catch the sap. Modern methods have improved the efficiency of collecting the sap from multiple trees into a central holding tank. Becasue the sap consists of mainly water that must be evaporated to concentrate the sugar, it takes about 40 parts sap to make 1 part syrup. Currently manufacturers use reverse osmosis to remove up to 75% of the water content without heat. They boil the concentrated sap for flavor development and sugar concentration. Ideally, maple syrup is 65% sugars, with 62% in the form of sucrose and 3% glucose and fructose. The remaining 35% is mainly water with some malic acid and other impurities.

The flavor of maple syrup comes from sugars, acids, vanillin (a wood by-product), and the products from sugar caramelization and browining reactions. The longer and hotter the syrup is boiled, the darker the color and heavier the taste. Maple syrups are graded based on color and flavor. Garde A maple syrup is to be consumed directly whereas Grade B is used mainly in cooking. Maple syrup is expensive, so most supermarket syrups contain little or none, but rather are artificially flavored.