Just between us: the light (A) and extra light (AA) classes are good for export. They're admired for their transparency and are well-suited to being displayed in attractive marketable glass bottles of various shapes. But on the gastronomic level, they don't have much flavor. Medium (B) provides a subtle flavor when added to salad dressings or poured over pancakes… but when it comes to cooking, the choice is obvious. You need C (amber) or D (dark) to obtain real depth of flavor.

Since maple syrup is a totally natural product, the flavor and quality vary a great deal from region to region and from year to year like other natural products such as olive oil and wine.

Storing Maple Syrup
If you stock up on maple syrup during the sugaring season, it's best to store it in the freezer, though room temperature is acceptable. Once it's been opened, store it in the refrigerator to slow down the evaporation process, or freeze it for 1 to 3 months if you will be using it only intermittently, since in a humid environment the syrup tends to crystallize.

Maple butter and taffy will keep for about a month; maple sugar, when well wrapped, can be frozen for up to a year. Just grate some from the block as needed.