Maple trees strive in cooler climates and because of that fact, maple syrup is made in the northern tier states of the United States. You can find maple syrup production from Maine to Pennsylvania, Ohio to Minnesota and all the states in between.
To have maple sap flow from maple trees requires below freezing temperatures at night (24 to 30 degrees) and above freezing during the days (38 to 44 degrees). Maple trees should be 10 inches in diameter or larger to be tapped. It takes approximately 40 years for a maple tree to grow to that size.
The process of making homemade maple syrup involves several steps. The first and most important step is having a supply of sugar maple trees, commonly known as a sugar bush. The trees have to be at least 10 inches in diameter to be tapped (small hole drilled into tree). Once the trees are tapped, a spout is inserted in the hole and the sap that comes out of the tree has to be collected. The old way of doing this is to hang a bucket under the spout and the sap drips into the bucket. When the buckets fill with sap, the sap is gathered by the owner and his helpers and brought to the sugarhouse.
In the modern times, the trees still get tapped, but the maple syrup producer uses a type of spout that attaches to a tube. The sap travels in the tubes to a central holding tank which, when full, gets emptied into a transport tank on a truck. The sap is transported to the sugarhouse and is unloaded into large storage tanks. The sap is then filtered and pumped into the evaporator.
The evaporator boils the sap and as the name suggests-evaporates the excess water out of the sap. As more water evaporates the sap gets sweeter and thicker and starts to change color. When enough water is evaporated and the sap is thick enough, the liquid is now considered syrup. The syrup is checked for proper density (thickness) and color graded.
There are four different grades of maple syrup. Grade A Light Amber-very light in color with a very delicate maple flavor, Grade A Medium Amber-a little darker in color with a more pronounced flavor, Grade A Dark Amber-darker still in color with a robust maple flavor, and Grade B- the darkest in color with a very strong maple flavor. Most people consider Grade B good for cooking because the flavor is strong enough for recipes, but some like it on pancakes and ice cream. Maple syrup contains 68% carbohydrates, while most other syrups contain 100%. While it has virtually the same caloric content as white cane sugar (50 calories/Tbsp), maple syrup contains significant amounts of calcium (20 mg/Tbsp) and potassium (35 mg/Tbsp), small amounts of iron and phosphorous, and trace amounts of B vitamins. Its sodium content is low (2 mg/Tbsp).
Store maple syrup in your freezer to retain flavor and quality over an indefinite period of time. The syrup will not freeze solid and will require about one hour at room temperature to bring it to pouring consistency. The amount required can be removed from the container and the remainder may be returned to the freezer.
If, after extended storage, mold should form on the surface of the syrup, the original quality can be restored. Remove the mold, heat the syrup to boiling, skim the surface, sterilize the container, and refill with the syrup.