While reading through Bamforth and Lewis’ “Essays in Brewing Science” I came across this interesting statement on page 87:
“crystal malts require pale malt for adequate extraction”
Up to this point I always believed that no enzymes are necessary for proper extraction from crystal malts which is why can steep them. But I was always wondering if it is truly the case that crystal malt’s sugars are not affected by enzymes. I.e. can active b-amylase make some of the extract from crystal malt more fermentable during the mashing process? That problem however is not necessarily what they mean with the above statement.
I’m thinking of an experiment that could demonstrate if Bamforth and Lewis’ statement is true: 3 mashes with the same mash thickness but different grists (100% carapils, 50/50 carapils/pale malt, 100% pale malt) mashed for 1 hour at the same temperature. Ideally the mash pH should be the same and may need some control since these 3 grists are expected to have different distilled water mash pH values. Level of extraction is then assessed by testing the gravity of the mash liquid. That is then put in relation to the potential of the respective grist and if the 50/50 grist is truly doing better than the 100% carapils grist there might be something to this.
Not that this has far reaching implications in brewing, it would just be good to know to satisfy the inner geek.
This may be a silly question, but how would gravity measurements let you know whether a sugar is more or less fermentable? I’d imagine that this could only be determined after fermentation with equal pitch rates and yeast strain based on the terminal gravity.
yes, that is correct. Threw in the statement about fermentability b/c it was just another though I had on the subject itself. Fermenting the produced wort in a fast ferment test setting might be able to show that. But to do that I rather do an experiment where I extract only the enzymes (cold water steep) and add them to a mash of only crystal malt. The control would be the addition of a boiled enzyme extract. The latter would compensate for the fact that even a cold water steep extracts extracts some sugar from malt.
Now that I think about it, that might be an experiment that is much better controlled than working with different grists that may cause different mash pH conditions. After fermenting the resulting wort, It would also be able to tell us if enzymes have an effect on the fermentability of crystal malt.
I don’t believe (I don’t know, have never tested) that all the starch in crystal malts has been converted. It is in this starch conversion that I believe that base malt (with enzymes) will assist.
That makes sense to me, and I’ve always sort of assumed the answer is yes.
I’ve been wondering about the actual extraction question for a while though. It would come down to whether or not all the starches in the endosperm are converted during malting, right?
Unless I’m mistaken, Kai’s talking about testing extraction potential, not fermentability. For the moment, anyway. ;)
Fred, if that is truly the case we would have to advise against simple steeping of specialty grains since that could cause the release of starches into the wort. But so far I have not heard of excessive starch haze in extract + steeped grain beers. This is also easily tested with an iodine test.
That makes sense to me, and I’ve always sort of assumed the answer is yes.
I’ve been wondering about the actual extraction question for a while though. It would come down to whether or not all the starches in the endosperm are converted during malting, right?
I changed my mind. I think it would be a more useful experiment if I were to test fermentability as well. I have done these experiments before with bread yeast and they are not that difficult to conduct.
No, that is actually better than my initial approach. I’m always interested in eliminating as many factors as possible and to have a good control. One problem is, that I cannot be sure that I will get 100% conversion efficiency from the pale malt. I.e. not all the starches may convert and if that happens the pH, which will be different since even cara pils brings down the pH a little, can affect the level of conversion. With the modified approach I don’t have to worry about that since I’m going to use onlt the enzymes extracted from malt. The control will have the enzymes disabled by boiling.
Wouldn’t it be best to first see if the crystal malt can actually convert itself? You can test different lengths of time steeping just crystal malt; maybe after 20, 40, and 60 minutes, and even longer if you have to. This may tell you whether crystal can actually convert itself, and, if so, how long it would take.
I am assuming the length of time would matter a lot because specialty malt doesn’t have much diastatic power, and the added time would allow the enzymes to “get around” to all the starch. (Unless enzymes denature over time?)
It seems many extract brewers do not wait all 60 minutes while steeping. I know I was instructed by my LHBS to just wait 30 minutes. Doing one test at 60 minutes may give you a false impression because at that point there may have been enough time for the conversion.
Wouldn’t the test I described answer directly whether “crystal malts require pale malt for adequate extraction"? If it can’t convert itself, then you would want to move on to step two to determine whether base malts would help get adequate conversion, and how much they help.
I think you may be confusing extraction and conversion to some extent. Crystal malts are mashed in the husk, so that conversion of starch to sugar has taken place (to what extent may be debatable). They’re then kilned, so I would expect that at least in the case of medium and dark crystal the enzymes have been fully denatured.
Extraction of the starches/sugars into the mash water, though, I would have thought was independent of having enzymes in the mash. Kai’s source seems to indicate otherwise.
Note the asterisk by the brown, dextrin, and light crystal, to which he states: “The low extraction from steeping is attributed to unconverted, insoluble starches as revealed by an iodine test.”
That would suggest that for (brown and) light crystal malts, not all the starch is converted during the malting process.
It has been a long time that I read his page or book and wasn’t aware that he already has this info there. If that is true, and it likely is, shouldn’t we then advise against steeping light specialty malts since they release starches into the wort that cannot be converted? This also tells me that I should test light and dark crystal malt.
And, it has always been my understanding that carapils should be mashed to prevent haze. Although, I don’t recall it ever being inferred as a necessity with other light crystal malts. Would be interesting to have more data on this topic.
Pretty much. Maybe say “stuff” instead of “sugars”. Brewers tend to use “sugar” to mean anything up to tri- or maybe tetra-saccharides. Things that are a little bigger than that are called “dextrins” and bigger than that are “starches”. Extraction just refers to the mechanical process of dissolving all those various carbohydrates into water. Once they’re in solution enzymes can start to break starches down into sugars, which is what conversion is.