Processing sap with heat in the evaporator is essential. The reactions responsible for the development of maple syrup's characteristic color and flavors require heat to proceed. Syrup produced by methods with little or no heating, such as freeze-drying or vacuum distillation, is nearly colorless and flavorless. The starting sap has the biggest role to play in what type of syrup is going to be produced on that day. Producers equipment can have an influence. But by and large, it is the sap you have on that what which will determine the syrup you will produce.