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Vermont: Energy, to be Syrupy Sweet

Mark Green

Mark Green
Posted October 31, 2017

“Sugaring Season” runs from March through May in Vermont, but the full exertions of the state’s sugarmakers, the producers of nearly half of the United States’ supply of maple syrup, are year-round. These become especially public in the fall, when tourists come for the fall leaves and maybe a taste of the authentic stuff that makes breakfast and other meals so sweetly enjoyable.

Download: Energy is Vermont

The maple syrup you pick up during a fall jaunt to Vermont or at your local supermarket is the product of a lot of work – and energy. There’s the tapping of the trees to collect sap, the sugaring and the bottling.

The process is intense, both from a labor and energy standpoint. Vermont’s 1,500 sugarhouses produced nearly 2 million gallons of maple syrup in 2016, which certainly covers a lot of flapjacks. It’s a big industry for the state, representing more than $317 million in sales and supporting more than 2,700 full-time jobs in 2013.

Collecting the Sap

The process starts in the summer months, when the leaves on maple trees produce sugar, which is stored as starch in a tree’s roots. In February sugarmakers come knocking, tapping trees for their sap, a clear liquid made up of 98 percent water and 2 percent sugar. This is done by hammering stainless steel spiles into the trunk and allowing the sap to collect in buckets. Stainless steel is manufactured using various forms of energy, including natural gas, to power furnaces.

Although tapping individual trees and hanging buckets on them is the time-tested method of extracting sap, many farmers today use a tubing system that eliminates the need for hundreds and thousands of individual sap buckets. Plastic spouts are inserted into trees, which are connected by plastic tubing to funnel the sap into the sugarhouse. Syrup makers like Amber Ridge Maple have 20,000 trees connected by tubing, amounting to 20,000 gallons of sap collected per day. The plastic used for this system is derived from natural gas or petroleum.   

Collecting Maple Sap Infographic

To get the sap to run through the tubing, some farms use the high slopes of their land to create a vacuum system, while others need sap pumps to push the liquid through. These pumps can be made from fiberglass-reinforced thermoplastic or stainless steel. Like steel manufacturers, glass producers and fiberglass makers use natural gas during production. The pumps are powered by electricity or gasoline.

Making a Sugary Treat

After the sap is collected from maple trees, it is placed in the sugarhouse in storage tanks, often made from stainless steel, polyethylene or fiberglass. Polyethylene, similar to steel and fiberglass, requires energy to manufacture – combining ethylene molecules most often derived from natural gas.

From storage tanks some sugarmakers then put the sap through a reverse osmosis machine before boiling. Because it takes about 42 gallons of sap to make a gallon of syrup, this equipment speeds up production by more quickly removing water from the sap, raising the sugar content to 8 percent.

Next, the sap is placed in flue pans and boiled in an evaporator that is either wood or oil-fired. These pans, with deep corrugations on the bottom to help accelerate the boiling time, are made of stainless steel. At this point the sap is finally turned into syrup, containing nearly 67 percent sugar.

Turning Sap into Syrup Infographic

Bottled To Go

Some sugarmakers bottle syrup throughout the year to ensure their product is fresh year round – so their work does not end in the late spring. The bottling process involves heating the syrup to approximately 190 degrees. Some producers build a wood fire in an outdoor pit, or use wood or oil-fired evaporators inside a sugarhouse. Other options include using an outdoor grill or the kitchen stove, which may use propane or natural gas.

You have to heat the syrup before bottling – especially in plastic bottles – to prevent fermentation. Heating also sterilizes the bottle’s cap area and activates its seal.

Energy also is involved in making the plastic bottles themselves – made of natural gas or feedstocks derived from petroleum refining. As we’ve pointed out elsewhere during this series, refining changes crude oil into petroleum products and foundational chemicals.

Whether a maple farmer with 40,000 taps or a hobbyist using a camp stove or a gas range to boil sap, sugarmakers rely on energy. Mother Nature provides the sap; energy brings tasty maple syrup to your family’s kitchen table.

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Mark Green joined API after a career in newspaper journalism, including 16 years as national editorial writer for The Oklahoman in the paper’s Washington bureau. Mark also was a reporter, copy editor and sports editor. He earned his journalism degree from the University of Oklahoma and master’s in journalism and public affairs from American University. He and his wife Pamela live in Occoquan, Va., where they enjoy their four grandchildren.