KernelCrush said:
Can someone define 'wort correction factor'.
It's an individual number for your refractometer based on observations between a calibrated high resolution hydrometer and your refractometer.
It is: Temperature corrected hydrometer reading converted into Plato divided by your observed plato reading.
The result is the multiplier applied to your refractometer readings.
***OPINION:
Here's where it gets weird, bordering on religious, to me... The conversion relies on observations and varies widely from refractometer to refractometer. Kai notes he MULTIPLIES by 1.04, where another article cites DIVIDING by the same number. Some see as little as 1% difference; then there is your observation, KernalCrush, which is an 8% difference (1.08 factor).
So KC, when I try to get details about this I get just as confused as you. The information all agrees that its sort of a "big deal," but there's no consensus about what the deal actually is.
It seems to me that with an observable difference between sugars there would be a predictable model of variation. There isn't.
I already covered how wort differs from "purer" sugar solutions; and even with different mash techniques the malt component profile percentages don't vary as widely enough to account for the variation between authors.
Which makes me think that what's really being done is compensating for optical differences between cheaply made prisms. Again, just my opinion.
I believe that a key to good brewing is just recording what you observe. Don't try to record what you THINK you should observe. The same is true of evaluating your beer quality.