Burnt Flavor

[Adk sugar bush]

Would appreciate some insight. Ok, so last year I ended up throwing out about 15 gal of syrup that had an off-flavor. Burned bitter taste.
I have a Grimm 2x6 evaporator (2x4 flue and 2x2 finishing) - boiling 100 taps, which last year put on 3/16 (worked great.) I have float in the back, but manually transfer to front pan. So, back to the problem. I suspect it was caused by foaming in the flues, burning on the edge of pan. I’ve searched past posts and two things are suggested. One is to keep level in both pans at about 1 1/2” to decrease time in the pans, and the other is to clean pans more often.
That said, wondering what people think about the level and also do you clean the pans often? Cleaning, I guess requires emptying sweetened sap and starting from scratch. How often? Any other suggestions - ie any way to minimize burned foam? It’s really discouraging to get to syrup stage and not have quality product.
Thanks

[O3C]

Have the same evaporator and the same problem. Have to watch the middle of the finish [ syrup ] pan that it is not going to syrup before it is making syrup at drawoff. Lessons I have learned on this forum is to put a thermometer in the middle section to moniter temperature. When that is higher than drawoff temp, take a pan or two of almost finished and pour it back in the start of the finish pan. I'll also start drawing off a little bit light just to get it moving, you can always adjust heavy later. I run my pans 1 1/2 so I am not burning pans ! Everytime I try to go shallower I get nervous especially during a long draw. Hopefully some one with more experience will chime in . Ron

[DrTimPerkins]

Sounds like burnt niter off-flavor. How much niter was built up? How were you cleaning pans?

[sugarman3]

Cleaning your front pan is what you need to do,not back pan,i am fortunate to have a RO and every night drain front pan and put 3 in of permeate in front pan,let set overnight ,in morn it is generally all loose,brush ,rinse and put back in front pan what you drew off

[Adk sugar bush]

Thanks folks. Funny, nobody thinks it’s the burned foam - which was my thought. So, cleaning niter seems to be consensus. I’ll look into best cleaning. I’ve just used wire brush and hot water. No good? I think I read somewhere here to use vinegar, but will search again. One more (last) question - are we talking just cleaning the finishing pan between boils?

[ecolbeck]

Vinegar works great as does permeate from an RO. The finishing pan is the only one to worry about. Cleaning frequency depends on how fast the niter builds up. It could be required once every several boils or in the middle of a boil.

[SeanD]

Definitely clean your front pan more frequently. Don't use a wire brush. Drain your front pan and set aside. You can run it through a pre-filter or two to catch some of the niter that's suspended in the sweet. I give the pan a little splash with water to get all of the sweet out. Then put at least an inch or two of vinegar or permeate and let it soak overnight or until your next boil. I drain the vinegar and reuse it all season with no issues. Everything that was baked on will wipe off with a finger or a sponge. Rinse it well. Put your sweet back in and you are ready to go. Do this after every boil and it becomes a simple routine. You'll see and taste results immediately.

[MapleMark753]

I sure can't argue against the burnt niter observations, they are true. I HAVE however ALSO had foaming and the light burning of that foam on my pans, particularly in the first couple years. Not the bottoms of the pans, the higher edges where the foam reaches. Baked on and burned. That flavor can contaminate the entire batch, or several hours worth of syrup. My solution for that was better sealing the pans on the arch with rail gasket, keeping the pans cleaner and free from almost burnt foam, and having the sap level just a bit higher and deeper. Good luck!

[Adk sugar bush]

Thanks on he foam ideas. This issue really is my biggest conundrum of the whole system (ie tapping, lines, storage, etc.)
I also won’t argue with the niter idea folks - as all good suggestions, but really do think a major portion of the problem is the foam - burnt edges just as you describe. Cleaning finishing pan niter between boils I can handle, but still at a loss as to how to keep foam from burning. I have a hood over flue pan which makes skimming foam a little more difficult. Maybe this year I’ll try without the hood (sacrificing efficiency) allowing me to skim better. Will also try sealing firebox as you mention. I guess the idea here is to keep heat from escaping up the sides of the pan - and keeping edges cooler. Makes sense.

[Sugarbush Ridge]

NEVER use wire brushes or anything steel or iron on stainless steel. Stainless steel scrubbing pads or copper, brass. Steel, iron will cause stainless steel to rust, as some iron will enbed into the stainless and will then rust.

[ronewold]

One thing you might be missing here is that the foaming can be related to the niter buildup. More niter makes the front pan foam more. So cleaning will help with both potential causes. Also, you haven't mentioned your defoamer usage- do you use it regularly, and does it help? You should use some regularly, and if it doesn't help much, that is a sign that you might need some pan cleaning.

[Adk sugar bush]

Thanks all. Will take suggestion to the camp. Here in upstate ny, it’s still really cold - as in single digits, but hoping to tap and start this weekend.