Grain color question

Hey all,

I've spent quite a while googling and searching this forum trying to figure why malt data lists Lovibond = SRM, with no success. For instance, Caramel 20L is listed as 20 SRM. I suppose there is a explanation for this, just would like to know it. It seems to that BS estimated beer color with 20L = 20SRM do not match the color reported by the authors of some recipes. I get closer using 20L = 26.2 SRM, for instance.

Thanks, W. 

Greetings. As I understand, the Lovibond and SRM both reference the same thing....color. If the grain and adjuncts are adding into BS are exactly as they are stated in a recipe you're trying to mimic, the numbers should be the same.  If they're not, try adding the exact same recipe into any one of the many on-line recipe editors to see the results.  You may be trying to mimic bad information.

https://brewwerks.azurewebsites.net/

Good luck!

Reading this may help in understanding the differences:  http://beersmith.com/blog/2008/04/29/beer-color-understanding-srm-lovibond-and-ebc/

These days, Lovibond these days is usually used for testing malt color which is a visual or spectral measurement of the reflective color of a solid.  SRM us pretty much used to describe beer color which is measured by transmitted light.  By the nature of the measurement differences, they will not be equal.  Thus the Morey equation which relates the malt color to the ending color of the beer made from those malts.

There are also a number of other modifiers caused by the individual's brewing process which can increase the ending color of the wort above what the equation calculates.

Thanks for the replies, and the link for info on colors. I've got a bit of the science of beer color scales, that was really cool. But my problem is actually very practical. I'll use  concrete example. Take this milk stout recipe, in BS report format:

http://www.homebrewtalk.com/showthread.php?t=139820

You can see that estimated color is 41.5 SRM, using Roasted Barley (300 SRM). Searching BS data base, you find Briess Roasted Barley rated 300 SRM, fine. This is inconsistent with the malster data sheet for this malt, which says it is 300L = 405.6 L. So, I conclude that BS makes SRM=L, regardless of the malt data sheet. The same is true for every Crystal Malt I verified in BS data base: If you look up the malt data sheet you find that BS takes SRM=L, even though it is not.

I reckon it is not a problem if you are always using the same scale. Whatever imprecision there is, you will be consistent, it just like using different color names. Trouble is if you need to substitute and take another scale as reference. As it turns out, that is the case for me, very often. I only have access to European Malt, with every choice of Roasted Barley rated at something around 500L. I figure I need to substitute aiming at 41.5 SRM. But my BS data base for Belgian Castle Roasted Barley says it is 609 SRM, consistent with Castle website specification, which says it is 375.6 L to 488.1 L. As a result, now we do not have SRM=L anymore.

So, my questions are:
1) should I alter de data base and make Castle Roasted Barley equal to 450 SRM?
2) Why BS data base lists  Briess Roasted Barley as 300 SRM when the malster data sheet says it is 300L = 405 SRM? , which is not. Is there a reason for this?
3) Estimated color isn't always off, since the color in data base is different from the malster data sheet?
4) When calculating substitutions, what is the relevant color? BS data base or malters data sheet?

I apologize for asking this much, but it is really confusing for me.

Thanks in advance.

This is an issue of labeling that has been around for a while.  The color of the malts should be labeled as Lovibond, but instead in the inventory are labeled as SRM.  In my working with BeerSmith, the only way to get the wort color close to predicted values is to enter the grain color in Lovibond units.  This is especially true with the darker malts where the two divert in values more significantly.

BTW, I consider the values in the stock grain inventories as estimates and update them regularly based upon the lot data I get from the maltsters. 

I will change the Castle data in BS to have everything in Lovibond figures, even though it is labeled SRM. If it works I am fine. Thanks for helping.

Don't assume that the default figures are in SRM!  Check it vs the maltster's data to check the actual color rating for each of the malts.  Most of the malts pre-entered in BeerSmith are actually already in Lovibond.