Off flavors/aromas, sources, and remedies

[DrTimPerkins]

Dr. Tim - when you talk about metabolism - is this the same thing as getting the "buddy" flavor/taste/ whatever at the end of the season?

No, metabolism and buddy are two very different naturally-occurring off-flavors. Metabolism is most frequently found early in the season, especially in light-colored/flavored syrup -- buddy is an end-of-season phenomenon. Both are (most likely) due to amino acids in the sap that produce the off-flavor when boiled, but they are caused by different amino acids. Metabolism is from nitrogenous amino acids -- buddy is from sulfur-based AA. In both cases they can't be detected until the sap is boiled. Some people can't detect metabolism off-flavor (or smell) very well....others are very sensitive to the flavor (probably this is genetically based). Most everyone can taste buddy. Metabolism happens only occasional, but some sugarbushes are more prone to the problem. Buddy will happen every year if you collect really late-season sap.

[therealtreehugger]

Dr. Tim - Thank you very much for the clarification! I learn a lot from you, and everyone else here! Thanks!

[Sugarmaker]

Like Dr Tim, I was thinking this might be Metabolism also. It took me a while to figure it out. Luckily I had a freind who is a chemist and he was doing work to find out why his syrup smelled funny and tasted funny.
During that same time And several times since I have made metabolic syrup. Yes its from the trees nit you.
The thing is did you ever make good syrup? If the answer is yes then you have to see what changed in your process. If nothing. Then this flavor and aroma variant from the trees could be the issue. Lots written about it. But it is illusive. Can occur in varying degrees at any time in the season.
My worst case was very late season tapping. The sap even tasted a little flat.
Cardboard flavor to really bad mr YUK taste is the range. You can smell it in the steam as it boiling too.
Hope this helps a little. Be aware this may not be your problem. You need to try to rule out any thing that may have changed in your process too. Sometimes it takes a while to find the answers.
Regards,
Chris