Because of food rationing during WWII, people in the Northeast were encouraged to stretch their sugar rations by sweetening foods with maple syrup and maple sugar.
Storing Maple Syrup
Pure Maine maple syrup contains no preservatives and should be refrigerated or kept in a cool dry place after the seal is broken. Properly prepared maple syrup will not freeze, and the freezer makes an ideal storage place.
It also may be heated to 180 degrees and canned in sterilized jars. Process pints in boiling water for 10 minutes.