posted 5 years ago
Hi I just wanted to follow up on this. I did some investigating... For the commercial sap drinks, the sap is frozen first and sent to huge facilities where they can process it with a lot of pressure and heat that we can't do at home.
For us, we learned like with most things, if you want to preserve it without fermentation you have to acidify. We experimented with different things including sumac, hibiscus, pine needles (P. strobus) and lemon juice. All worked really well except for the pine needles. Citric acid is of course an avenue as well. After getting it to the desired PH we pressure canned the sap. It's quite a bit of energy to go through the whole process but it makes for an incredible drink that we have been enjoying on special occasions.