19 Mar 2016

Make Mine Maple

by Helen Mason

At the first signs of spring, when the days get longer, the snow begins to melt from around the roots of the maple trees, and the temperatures rise to slightly above freezing during the day but stay cold at night, the sweet sap in the maple trees begins to flow. That's when both professionals and hobbyists tap sugar maples for sweet sap that is boiled until most of the water has evaporated. What's left is an amber-coloured liquid called maple syrup.

Sugar bush in early spring
The sugar in this sap was produced the previous year when sunlight, reacting with the chlorophyll of the leaves in sugar maples, produced sugar. This sugar was stored in the tree and released when the spring warmth caused the sap to rise from the winter-frozen roots.

Sugar maple trees are unique to eastern North America. Their sweet sap was first harvested by Aboriginal tribes during the "maple moon."

French and English explorers wrote of the "sweet water" that North American Indians took from the trees and boiled down to a coarse dark brown sugar. In the 18th and 19th centuries maple sugar was an important food item and was used for trading. By the late 19th century, however, white cane sugar, which was cheaper and easier to get, replaced maple sugar as the sweetener.

This hobby bush is in a sugar maple stand near Parry Sound, ON.
Today, maple syrup and sugar are made both by hobbyists and professionals. Commercial bushes use pipeline to move the spring sap to an evaporating shed where it is boiled in large commercial evaporators. Many hobbyists tap a small number of trees and make just enough syrup for their family and friends.

In 1980, Mark Mason used a battery-powered drill to tap.
In small bushes, the process begins when the hobbyist drills a hole in the tree trunk to collect some of the sap as it rises. A cone-shaped funnel or "spile" is hammered into each tap and a bucket hung from the hook attached to each spile. As each day warms, sap plinks into the buckets, creating a springtime maple melody.

In most bushes, the sap is collected and poured into a large flat evaporating pan. The sap is boiled until the watery liquid gradually turns from pale yellow through gold, to a warm amber. This process uses up a lot of firewood, gas, or propane. In some commercial bushes, it's sped up by reverse osmosis.

Partially boiled sap is poured into a hydrometer cup. Is it maple syrup yet?
The work demands patience. About forty litres of sap produce only one litre of maple syrup. Making it demands hours of boiling, buckets of patience, and many maple trees.

As the temperature of the boiling sap begins to rise, the specific gravity is checked. The finished product has a specific gravity of 1.37 and boils at exactly 104 °C. Traditionalists use a glass column called a hydrometer that will show about two-thirds of its length when the correct specific gravity has been reached.

A felt sock filter purifies some dark syrup from late in the season.
Once the syrup reaches this stage, it's quickly removed from heat, filtered to remove any impurities, and bottled or canned, ready for you to enjoy over pancakes or in your favourite maple recipe.

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