(RESOLVED) Conversion efficiency and sugar


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Feb 4, 2013
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I just brewed a recipe that used cane sugar and from what I can tell, the conversion efficiency calculation doesn't factor out the sugar, so my conversion efficiency (actually, all the efficiencies) is higher than it really is since you're always going to get 100% conversion for sugar. It seems to me that the efficiencies should only look at grains.

Is it possible to make it ignore sugars for the purposes of the calculation? Or do you expect that sugars are always added after going into the fermentor? I like to add them to the boil so my gravity readings are in line with what the final OG should be.

Re: Conversion efficiency and sugar

The efficiency logic is specifically coded to factor for any raw sugars in the recipe. Please share the recipe, and post your numbers so we can trace through it and make certain.

The system assumes that raw sugars are counted in the boil complete and brew day complete gravity readings - but not in the mash complete or pre-boil readings (since raw sugar is generally added after the boil starts).
Re: Conversion efficiency and sugar

I added the sugar at the start of boil, stirred it in and then took a gravity reading. I can't seem to get consistent gravity readings before the boil starts because of the stratification in the wort.

Glad you're accounting for that in the first 2 efficiencies. I'll just add sugar after I enter those values.
Re: Conversion efficiency and sugar

Stirring in the kettle should give you a solid gravity reading.

Are you using a refractrometer? Mine is all over the place, I have to calibrate it each time. Its a $40 unit, and I don't really trust it.

If you are using a hydrometer, make sure the sample is cooled down and temperature corrected (using our stand alone calc, or the one built into the brew log entry dialog). You should not get wildly different readings with a hydrometer.
Re: Conversion efficiency and sugar

Everything I've read says that it's near impossible to stir the wort enough to consistently mix it and my experience backs that up. Or maybe I'm just a lousy stirrer!

I am using a refractometer. I get consistent results whenever I use it except for pre-boil, when I get readings that differ by 10+ points and I assume that's because of the stratification.

I've found the best way to use a refractometer is to take samples with pipettes and let it cool for 30 seconds. The pipette keeps the moisture inside so the boiling wort doesn't evaporate and give you bad reading. If I do that, my readings are consistent. And keeping the refractometer in a constant ambient temperature and only measuring cooled liquids keeps it calibrated.
Re: Conversion efficiency and sugar

The conversion efficiency is for the gravity of the mash. You should not add sugars to your mash since they don't need to be converted and you'll end up loosing some in the spent grain.

Re: Conversion efficiency and sugar

Yeah, the site does the right thing, I assumed it wouldn't and I had to count the sugar's gravity to make it work. :oops: