Originally Posted by Cooking Goddess
Have you ever tried making the syrup by freezing/thawing/freezing the sap? I saw an article in an early 1970's Mother Earth News that said you could do it just that way. We have silver maples on our lot and I've thought of trying to make syrup via the freezing method with their sap, although it's probably too late to do it this year.
I haven't heard of that method. My understanding is that the sap has to boil at 7.4 degrees above the boiling temperature of water to reach the appropriate sugar concentration (66% on the Brix scale). I do freeze sap and make syrup later. It keeps for 12 months frozen.
The ratio of sap to syrup from Silver Maples is 100:1. A friend taps her Silver Maples. We did one year and blended the sap with that from the Sugar Maples. Now we just tap the Sugar Maples.
Is it too late? The ideal nighttime temp is -5C and daytime temps of 5C. Once the trees start to form buds, the season is over and it is time to think about planting the garden.