SRM and Efficiency

Hi all. I routinely formulate recipes using percentages for my grain bills. I usually get about 80% efficiency. I was converting Jamil's BPA to my system and noticed that my predicted SRM was 1.7 points lower than what Jamil had listed. I'm not really concerned as to matching the SRM specifically. I use BJCP as a guideline for unfamiliar styles, but don't follow it as gospel. I'm more concerned with the why in this situation.

I'm just wondering why that if I'm technically extracting the same amount of sugars from the specialty grains, then why am I not getting the same amount of color? Is the color contributed from specialty grain independent of the sugar extracted from the grain? For example, 6.1% Caramunich should get me the same sugar extraction and flavor profile at 70% or 80%, but why is the SRM different?

There is very significant batch to batch variation in malts. If a recipe lists caramunich and nothing else you could be using a 50L malt when the author was using an 85L malt from a different maltster from a different continent.

If you want to make consistent beer you should be getting all the info you can about your actual ingredients, and not using the defaults the software uses. You should keep an inventory that has this information and update your recipes everytime you brew them. This includes hops, alpha and beta acid levels change all the time.

Ovidsmuse said:

If you want to make consistent beer you should be getting all the info you can about your actual ingredients, and not using the defaults the software uses. You should keep an inventory that has this information and update your recipes everytime you brew them. This includes hops, alpha and beta acid levels change all the time.

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I do use updated color and gravity ratings. Obviously using ~.6lbs of 55L vs 62L malt isn't going to change the SRM a lot of points. There's going to be some variation regardless. Plugging in Jamil's recipe number for number (75L vs 60L) still gets me a pretty big gap. Obviously, this comes from using less specialty malt as this recipe of his is calculated for 70% efficiency. I'm just wondering if color compounds are separate from the sugar extraction.

Edit: I'm talking from a pure recipe planning standpoint here too. Regardless of source ingredients, lowering efficiency gets me a higher SRM rating and raising it gets me a lower SRM rating. Just wondering where that comes from.

Ok, I get your question now. For practicle purposes it is entirely dependant on the amount of grain of a particular rating vs the dilution of the solution, in this case the wort. The color compounds solubility is pretty uniform over a wide temperature range, and there is no enzyme conversion required, so it is not comparable to the starch to sugar conversion during the mash. This is why extract brewers can steep grains to get the color needed, and is what I would suggest doing if you wanted to get closer to the target SRM of the recipe without changing the SG significantly.

Ovidsmuse said:

Ok, I get your question now. For practicle purposes it is entirely dependant on the amount of grain of a particular rating vs the dilution of the solution, in this case the wort. The color compounds solubility is pretty uniform over a wide temperature range, and there is no enzyme conversion required, so it is not comparable to the starch to sugar conversion during the mash. This is why extract brewers can steep grains to get the color needed, and is what I would suggest doing if you wanted to get closer to the target SRM of the recipe without changing the SG significantly.

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Thanks for the follow up answer. I usually use others' recipes as a starting point the first time that I brew an unfamiliar style and was just curious what was causing the color disparity and that led to confused tinkering around in Beersmith.

A lot of people keep the amounts of all the specialty malts the same as the original recipe and adjust the base malt quantity depending on efficiency. Ovidsmuse stated the reasons much more thoroughly and elegantly than I would have.