mpj
New Member
I'm new to refractometers and a little confused. I'm currently fermenting a Belgian-style blonde ale and plan to bottle on Saturday. My ~20 litre batch used 5.6 kg of malt and 900 grams of clover honey, added in the last 5 minutes of the boil.
In the excitement of the brew day I neglected to take a hydrometer reading, but the refractometer read 15.2 Brix WRI. Using the standard 4% wort correction factor that's about 14.6°P. I know technically I'm using Brix and Plato wrong here, but find it clearer to think of uncorrected readings as Brix and corrected readings as Plato.
At the moment my beer sits at about 7.3 Brix WRI. Depending on the calculator used, that corresponds to a FG of somewhere between 1.008 and 1.012 and about 85% attenuation on Wyeast 1214. That's a bit higher than I expected; I guess it's due to the honey providing more glucose and fructose. For the record, my hydrometer reads 1.0085.
Now I'm wondering how the addition of simple sugars in the form of honey affects the wort correction factor, both in the beginning and towards the end of fermentation. I think it's safe to assume that the wort correction factor should be lower for a mixture of glucose and maltose than maltose alone. If that's the case, and if glucose is used up more completely by the yeast, does the correction factor change during the fermentation process? At least one of the calculators I've tried (Refractometer Calc on Android) allows me to set the correction factors separately for original and current Brix.
I realise a lot of this doesn't actually matter in real life, but I'd like to understand exactly what I'm measuring!
In the excitement of the brew day I neglected to take a hydrometer reading, but the refractometer read 15.2 Brix WRI. Using the standard 4% wort correction factor that's about 14.6°P. I know technically I'm using Brix and Plato wrong here, but find it clearer to think of uncorrected readings as Brix and corrected readings as Plato.
At the moment my beer sits at about 7.3 Brix WRI. Depending on the calculator used, that corresponds to a FG of somewhere between 1.008 and 1.012 and about 85% attenuation on Wyeast 1214. That's a bit higher than I expected; I guess it's due to the honey providing more glucose and fructose. For the record, my hydrometer reads 1.0085.
Now I'm wondering how the addition of simple sugars in the form of honey affects the wort correction factor, both in the beginning and towards the end of fermentation. I think it's safe to assume that the wort correction factor should be lower for a mixture of glucose and maltose than maltose alone. If that's the case, and if glucose is used up more completely by the yeast, does the correction factor change during the fermentation process? At least one of the calculators I've tried (Refractometer Calc on Android) allows me to set the correction factors separately for original and current Brix.
I realise a lot of this doesn't actually matter in real life, but I'd like to understand exactly what I'm measuring!
