Brewing Beer from Malted Oats
I stumbled across an article on brewing with 100% malted oats. Mike Retzlaff goes into some interesting details on oat malt which I wont go into in this post, so click the link below and read his article.
I have brewed a few beers with 100% oat malt, namely the Horner Bier, after reading Mikes article I would recommend the following mash schedule in place of the single infusion I suggested previously.
Mash schedule 100% Oat Malt
45 oC 113 oF for 20 minutes as a β-glucanase (cytolytic) rest
62 oC 144 oF for 30 minutes as a β-amylase rest
72 oC 162 oF for 30 minutes as a saccharification rest
78 oC 173 oF for 10 minutes as a mash out
I have found Oat Malt to be a game changer for many of my beers, Oats help with body, mouthfeel, head retention and lacing. My Horner Bier had absolutely amazing foam retention even after bottling. Considering the information in the article I am thinking that 20-30% Pale Oat Malt in a Rice/Millet Grist will help contribute some of the needed enzymes for the mash without adding bottled enzymes, or minimizing the enzymes needed to something cheap and easily available like GlucaBuster from cellar Science. Including Rice or Millet with Oat Malt as a portion of the grist I would make a few adjustments to account for the gelatinization of rice and millet.
Proposed Mash schedule 70% Rice/Millet 30% Oat
45 oC 113 oF for 20 minutes as a β-glucanase (cytolytic) rest
62 oC 144 oF for 30 minutes as a β-amylase rest
72 oC 162 oF for 45 minutes as a scarification rest perform iodine and gravity
78 oC 173 oF for 45 minutes CHECK for full conversion and check gravity at the beginning and end of this rest. if needed follow up with 185f for 30 minutes
When mashing with Rice and Millet I see most of my conversion at 170-180f (on my anvil 10.5). Now that is with exogenous enzymes so this step may denature the natural enzymes so adding some heat stable enzyme may be needed. Checking for conversion with an iodine test and gravity measurement between steps is to inform us on what is happening and at which temperature. PH control is key to GF Mashes even more so than in the Barley world with a target of 4.9-5.2.
In conclusion utilizing Oat Malt in GF Beer has fantastic results and has the potential to radically change how we mash our GF Grists.
PROST!