EBC Calculations - Linear vs Morey

[Grumpydev]

There seems to be a bit of a religious "war" between those that side with Wheeler and the linear EBC calculation, and those that side with Morey with his non-linear equation and I'm curious what peoples experiences are?

Morey claims the linear doesn't work once you get to a certain level of EBC, but checking out forums for most of the software (which almost invariably uses Morey) there seem to be lots of people having issues with it under predicting darker brews. Wheeler says that Morey's work is a load of nonsense, and derived from bad science and bad techniques, and he promotes the linear method.

I've got a spreadsheet that calculates both values, and just to show the magnitude of the difference between them, the recipe I have currently I am aiming for around about an EBC of 60, and the two calculations give me:

Morey : 56
Linear : 146

Now one of those is "about right" (I'm aiming for a dark ruby), but the other is black hole black - which I definitely don't want!

So - anyone made their own darker recipes and can shed some light to which one, if any, is actually remotely accurate?

[zgoda]

Lab analysis with spectrosomething gave me identical result as linear method but this was single sample of 35 EBC beer.

[IPA]

Lab analysis with spectrosomething gave me identical result as linear method but this was single sample of 35 EBC beer.

+1
The linear method as per Beer Engine seems to work fine for me. Only way to check is to use the Morey method and see if you are disappointed. Then post the result and everyone will know which one to use.

[Grumpydev]

They both seem ok for around the 30 mark, but differ massively as you go darker (as expected) .. Think I will suck it and see and post back which is closest for me.

[zgoda]

Morey calculus is widespread and allows for comparability between breweries. For me there's no point in "being right" when others don't know what are you talking about.

[Grumpydev]

[quote="zgoda"]Morey calculus is widespread and allows for comparability between breweries. For me there's no point in "being right" when others don't know what are you talking about.[/quote]

Not sure I understand that.. If you are sharing a recipe the recipient can calculate the predicted colour however they like.. If you're not, and just comparing beer, then you compare from the EBC chart of *actual* colour, so how its calculated is irrelevant - my question is around how to predict the colour as accurately as possibly before actually brewing it.

[zgoda]

There's only 1 piece of homebrewing software that uses linear calculus and it has very limited use. Everybody else uses Morey. This might be wrong but my 50 EBC is the same 50 as in my neighbours brewery.

[Rick_UK]

I think it's just a case of getting used to one of the scales so you have a consistent point of reference - like celcius and fahrenheit. I started with recipes from BYOBRA so in my mind 200 is a dark stout, 100 is a porter or dark mild, 20-30 is an IPA. Problems come when its unclear which scale a recipe is using or you have to convert one to the other.

[Jim]

There's only 1 piece of homebrewing software that uses linear calculus and it has very limited use. Everybody else uses Morey. This might be wrong but my 50 EBC is the same 50 as in my neighbours brewery.

I'm not sure I go along with that. Surely the definition of the most accurate calculation is the one that correctly predicts the colour of the final beer from a given recipe (whichever one that is). What you seem to be saying is 'it doesn't matter as long as we're all wrong together'.

[IPA]

I'm not sure I go along with that. Surely the definition of the most accurate calculation is the one that correctly predicts the colour of the final beer from a given recipe (whichever one that is). What you seem to be saying is 'it doesn't matter as long as we're all wrong together'.

[Grumpydev]

[quote="Jim"]I'm not sure I go along with that. Surely the definition of the most accurate calculation is the one that correctly predicts the colour of the final beer from a given recipe (whichever one that is). What you seem to be saying is 'it doesn't matter as long as we're all wrong together'.[/quote]

Exactly - the colour scales are a standard, saying "my 100 is X colour" means nothing - a 100 should look like whatever the scale says it should look like, if the calculation doesn't give you that (or pretty close to it) then its plain wrong. Most software also takes the number and shows you a colour, which it takes from the chart; so if the calculation is not giving the correct value then that "preview" is essentially useless for anything above 30 or so.

These calculations are only approximations, but they need to be at least in the same ball park to be of any real use - if the calculation produced X "morey units" and we built a chart from that and used it for comparison then that would be valid, but projecting a calculation (either of them) onto an existing standard chart it has to match.

[zgoda]

I'm not sure I go along with that. Surely the definition of the most accurate calculation is the one that correctly predicts the colour of the final beer from a given recipe (whichever one that is). What you seem to be saying is 'it doesn't matter as long as we're all wrong together'.

Yes I'm saying exactly that. And just recently I found most of commercial brewers here either uses Morey tables in their spreadsheets or completely refuse to talk "EBC units" and use plain descriptions like "dark brown", "straw yellow", "deep gold" or so.

[Grumpydev]

That makes much more sense.. It would be awesome if someone produced a "morey units chart" though so we could get a reasonable prediction without everyone using trial and error

[IPA]

Here you go get one of these and then see if Linear or Morey correctly predicts the colour or "color"

http://www.beercolor.com/products.htm