Freeze-Drying

The insert on page 7-30 of NAMSPM includes the following:

"If sap is concentrated to maple syrup density using only a method like RO or freeze-drying, the result is a nearly
colorless, tasteless sugar syrup. This is because the majority of the reactions (“nonenzymatic browning”)
responsible for the development of color and flavor in maple syrup occur as sap is processed with heat. These
include Maillard reactions, a complex series of chemical reactions that begin with reactions between certain
sugars and amino acids, and are responsible for a variety of colors, aromas, flavors, and off-flavors in foods.
Sucrose does not react directly in Maillard reactions, but the invert sugars it can be broken down to, glucose
and fructose, do. "

What is the freeze drying of maple sap?

Freeze-drying is evaporation (actually sublimation) of water from a material using vacuum at below freezing temperatures. No heat involved.

An example is the so-called “astronaut ice cream.”