how long should fermentation be?

[JawnnyO]

I took the 'sweet sap' from my evaporator and added champagne yeast. It's really dark. I used an acid melange and yeast nutrient recommended by a home brewing store. OG was 1.094. It started fermenting April 12, and is still going. It was originally set at 16*C with my inkbird. After a couple of weeks, every two or three days I up the thermostat 0.5*C. It is now at 20.5*C. The bubbling continues, about every 15-20 seconds, which is not a a big change from the second week.
Any suggestions? I can't make any beer with the heater and inkbird currently in use.
Thanks

 

[IslandLizard]

Aside from the high gravity, there may be some complex sugars in that sweet sap mix that just take more time to gnaw down.
What yeast did you use?

If your ambient temps are steady and warmish in the low 20's (°C) or you have a place/area that is, put it there to let it finish out. The bulk of fermentation should be over by now, so her flavor/aroma profile is pretty much set.

That'll free up your ferm chamber (and controller) for a different batch.

 

[JawnnyO]

I used Lavalin EC 1118 yeast, one packet for about 4.5 US gallons.
My 'ferm chamber' is an unheated basement that maintains a constant 9-12*C throughout the year.
I just learned that The sugars in maple syrup are primarily in the form of the sucrose, with some glucose and fructose. Sucrose is a complex sugar that breaks down into the simple sugars fructose and glucose. So I guess most of it is complex sugars and I'll just have to wait it out.
Thanks for the response, I'm pretty new to brewing and brand new to fermenting maple sap.

 

[IslandLizard]

I guess sucrose is a "complex sugar" for EC1118, but she should be able to digest it. Although not common, apparently some distillers use it in their sugar washes.

There may well be much larger/complex molecules in there, like caramels formed during the extensive boil.

As with any sugary fermentations, using the right kind of yeast and nutrients is important.

 

[JawnnyO]

Is there a better yeast I can use next year? This is a once a year opportunity. Thanks

 

[hotbeer]

how long should fermentation be?

Didn't Pope Julius II (Rex Harrison) ask Michelangelo (Charlton Heston) a similar question in "The Agony and the Ecstasy (1965)"


[repeated exchange]

Pope Julius II: When will you make an end?

Michelangelo: When I am finished!

 

[Gnomebrewer]

Ignore the airlock. The bubbling could just be off-gassing or temperature changes (expansion). Take gravity readings to see if it's finished (two readings a few days apart - if gravity hasn't changed, it's finished or stalled).