Max non-diastatic adjuncts for several base malts

Does anyone know how to determine what the maximum percentage of adjuncts can be for various base malts, especially the ones below?

I have these malts on hand:

Great Western Pacific Northwest Premium Two-Row Malt (125 Lintner)
Paul's Pale Ale Malt (45 Lintner)
Maris Otter (49 Lintner)

I don't know for sure what their diastatic power is. All of the Lintner figures above are based on google searches. The values come from various anecdotal sources. I linked above to the source that I found. I am assuming that the North Country Malt in Canada is the same as the Great Western since both are owned by ConAgra and Great Western is the US distributor.

I'm going to brew a variation of YooperBrew's AG Corn Cream Ale, and I was considering using Paul's Pale Ale Malt and I'm concerned about having enough diastatic power to convert all the starches.

16 lb Base Malt (Paul's Pale Ale Malt) - 71.11%
4.5 lb Flaked Corn - 20%
1 lb Biscuit Malt - 4.44%
1 lb Cara-Pils - 4.44%

That's near 30% adjuncts. Will this work? If it won't work with Paul's, will it be OK with the American 2-row?

Also, does flaked corn need to be boiled before adding to the mash?

Diastatic power is a number that the maltsters assign to each malt they produce. The higher the better for any non diastatic adjuncts that need starch conversion in a given brew. In order to convert from starch to sugar you need a given amount of enzymes.
What you have listed will work great. There are no set rules that I have found relating to Lintner values verses non lintner producing adjuncts such as rice or corn. So far I just search on the internet for recipes that have worked well for others brewing nearly the same as what I am brewing and that has worked well for me. If anyone else has more input please chime in.

Well you don't have to worry about the Cara-Pils. No mash required. I think it's essentially the lightest possible Crystal.

I can't help with the math, but 35 Lintner means it can self-convert, so the Paul's has diastatic power to spare. If you're concerned, go halvsies between the Paul's and the 2-row.

I'm a little surprised about the L number you have for 2 row. It looks like a Kolbach number. If so, it is also 40 Lintner ( (125+16)/3.5 ). This is about the same a the a Maris Otter, which now seems correct to me, since they have similar properties.

Paul

You are safe if you stay below 50% adjuncts. I routinely do PM at that ratio.

LayMeister said:

I'm a little surprised about the L number you have for 2 row. It looks like a Kolbach number. If so, it is also 40 Lintner ( (125+16)/3.5 ). This is about the same a the a Maris Otter, which now seems correct to me, since they have similar properties.

Paul

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I believe 125 is probably right. 6-row is 160, and modern US* 2-row has been bred for higher protein content and diastatic power. Many sources on the internet say US* 2-row is typically 110 Lintner or higher in DP, and that British malts are considerably lower.

I edited my original post to link to the anecdotal sources I found. I don't regard these as being necessarily accurate, but the one for the American 2-row at least came from a malt distributors web site.


* EDIT: It is probably North American (US and Canada) 2-row in general that is higher, not necessarily US.

david_42 said:

You are safe if you stay below 50% adjuncts. I routinely do PM at that ratio.

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Thanks. This will be an all-grain full mash, not a partial mash. That would make a difference since I'm not adding any DME or LME, wouldn't it? The enzymes in the grains have to convert all the starches in the corn and biscuit malt.

I found this source that suggests that British 2-row adjuncts be limited to 15%, and I'm nearly double that. All About Grains 101.

Moonpile said:

Well you don't have to worry about the Cara-Pils. No mash required. I think it's essentially the lightest possible Crystal.

I can't help with the math, but 35 Lintner means it can self-convert, so the Paul's has diastatic power to spare. If you're concerned, go halvsies between the Paul's and the 2-row.

Click to expand...

Half and half might be a good idea just to be sure I fully convert everything.

I wish BeerSmith calculated this for you.

I used 15 lb Pauls Pale Ale Malt and 4.25 lb Flaked Corn, .75 lb Biscuit, 1 lb Cara-Pils. According to the iodine test the starches all converted.

Now I just have to work on recipe adjustment to match my efficiency. With only two brews so far on my new fly-sparge system, it's too early to draw conclusions, but I've overshot my OG target by a few points both times.

Just to add, from my conversations with various individuals, anything over 100 Lintner should give you a good amount of DP to convert "other stuff". When you really have to be careful is if the base grist is lower than 100, then you should take note. What can happen though, is your conversion will take longer and longer the more you push up the adjunct or specialty malts. Theoretically, or so I have been led to believe is that eventually even very poorly thought out combinations that have low DP *should* convert. The trick is, is it within a practical time frame?

Conversion was complete via iodine test in my case when I tested at 40 minutes into the mash. I mashed for 75 minutes. I was a little surprised that it all converted so easily since Pauls Pale Ale Malt has a Lintner value of 45. But I had called my LHBS to ask before I brewed, and they also told me it should be no problem for my grain bill.

Having some alpha amylase on hand would be a good thing if you are going to push the limits. I don't think I did for this brew.