Including some raw grain, and more generally un-malted ingredients in a grain bill can be beneficial for both foam retention and mouthfeel. In certain circumstances, raw grains (in combination with sufficient enzymes) may represent the only source of fermentables available.
Benefits of raw grain as an adjunct to malted ingredients
- Source of protein and beta glucan.
- Foam development and retention
- Haze (where appropriate to style, e.g. Belgian wit and some "wheat beer like" styles)
Raw grain and unmalted adjuncts
Unmalted "adjuncts" may be found in their natural, raw state, or they may have undergone some post-harvesting treatment that does not involve malting.
- Torrefied grains are produced by heating grains quickly to a high temperature until they "pop" (puffed rice and popcorn are examples of torrefied grains). The torrefaction process makes starches more accessible and does not require further gelatinization.
- Flaked grains (e.g. rolled oats and rolled quinoa) are steam cooked, then rolled flat and dried. The steam cooking provides pre-gelatinization.
|Lentils||Y||N||N||Can be roasted|
|Millet||Y||?||Y||Raw and to lesser extent, puffed, are fairly available to consumers.|
|Oats||Y||Y||?||Flaked oats are readily available to consumers|
|Quinoa||Y||Y||?||Raw and flaked quinoa are readily available to consumers|
|Rice||Y||?||Y||Raw and puffed rice are readily available to consumers|
Raw (unmalted) grains that have not been pre-gelatinized (i.e. flaked or torrefied) need to be gelatinized to make starches available during the mash. Because some grains and pseudocereals have a high gelatinization temperature, it may be useful or necessary to perform a "cereal mash" prior to the main saccharification mash with malted grains.
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Brewing from 100% un-malted grain
Raw ale vs raw grain
The term "raw grain" should not be confused with "raw ale" which is a brewing technique used in some farmhouse traditions (i.e. Norway) where the wort is never boiled. http://www.milkthefunk.com/wiki/Raw_Ale