University of Vermont

Helping Maple Make the Grade

Maple off-flavors

Pure maple syrup is a special, high-value sweetener that derives much of its worth from its unique flavor. Though consumers rarely taste sub-par maple, damaged or “off-flavor” syrup can and does occur. When syrup does not meet legal standards for sale, its value drops 50 percent. It is up to the producer to protect their bottom line by detecting off-flavored syrup before it reaches a retail container.

UVM Extension Maple Specialist Mark Isselhardt led the design of the off-flavor syrup reference set in 2017 to help producers become familiar with detecting the taste of naturally occurring off-flavors in syrup. The 1,600 sets produced contain three 1.7-ounce bottles of metabolism, buddy and sour sap off-flavors.

This project was a collaborative effort among a large maple syrup packer; the Vermont Agency of Agriculture, Food and Markets; and UVM Extension. Though most sets were sold to producers in Vermont, nearly 400 went to those outside the state. The North American Maple Syrup Council distributed kits to producers in 13 states and four Canadian provinces.

As the largest producer of maple in the United States, Vermont is leading the way in innovative solutions and best practices. The off-flavor syrup reference set is a perfect example of a tool that supports the long-term profitability of maple operations by increasing the amount of high quality, properly-graded maple syrup in Vermont.

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NIFA supports UVM Extension: This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture.