Sylvia Frisch, however, tried pressure canning the birch sap and storing it in her root cellar and it preserved very well and tastes great! Also, Sylvia Frisch took advantage of the natural yeasts in birch sap to try and make vinegar. She bottled fresh birch sap last year and added a few raisins or black currents in each bottle and stored them in her root cellar. Suzanne and Sylvia cracked one open last week at Birch Camp and it was a delicious light white vinegar. They have bottled some fresh birch sap with local low bush cranberries this year and will see if they have equal success. Will keep you posted! Suzanne talked about her search for locally-sourced vinegar on a recent episode of Yu-Kon Grow It on CBC North’s A New Day with host Sandi Coleman.