Base Malts
Like any structure beer must have a foundation, which is what we call “base malt.” When brewing with malt extract the choice of base malt has been made for you, but in the case of a partial mash/extract beer, or one from all-grain you have to choose it yourself. But before we get ahead of ourselves, what is base malt and what does it do in a beer?
Well, one of the most defining characteristics of beer is that it contains alcohol, which has been produced by the action of yeast on sugars. Not just any sugars, for there are some that yeast cannot ferment, but primarily simple sugars such as glucose, maltose, sucrose and to a lesser extent, maltotriose. These are produced in beer wort by enzymes that convert the starch in base malt to sugars during mashing. And of course the malt itself is derived from barley; there are other malts, notably wheat malt, which can perform this conversion, but they are generally used as base malts in a limited range of special beers, (and these will not be covered in this story.)
Base malts are the brewer’s workhorse, and form the largest proportion of the malt bill, usually at least 60–80% of the total. They are the beer’s source of alcohol, flavor foundation, some of its mouthfeel and body, and permit us to use whatever specialty malts and non-barley based grain starches we want to add. There are really only six of these, and they are as follows: pale malt, pale ale malt, Pilsner malt, mild ale malt, Vienna malt and Munich malt.
The first four can be used as the sole malt in the grain bill, and are true base malts. Vienna malt can also be used in this way although it is more often used in conjunction with pale malt. Munich malt (the very low roasted, low color versions – see later) can also be used as the sole source of fermentable sugars, but again is usually used alongside pale malt. In that sense these two are not really base malts, but I have included them because they are used in greater proportions of the malt bill than specialty malts.
Pale and Pale Ale Malt
These are the most important base malts and are used as such for the majority of beers brewed by craft and homebrewers. There are two basic types, 2-row and 6-row, which refers to the type of barley from which they are made. Six-row pale malt is very high in enzyme content and can hence handle quite high proportions of non-malt starchy grain adjuncts. Large commercial brewers mostly use them in this way since they are also high in protein, which can cause chill hazes in the final beer, unless low-protein adjuncts are added to lower the total protein content of the wort. Craft and homebrewers generally produce all-malt beers to get the kind of flavors they want, and prefer to use 2-row types partly to reduce the risk of chill haze formation, and also because they help to give superior flavors.
At one time there was a big distinction between pale ale malt and 2-row and 6-row pale malt (as well as European lager malts), pale ale malt being held to be “well-modified,” more so than the other base pale malts. What this meant was that the malting and kilning process for pale ale malt had been taken a little further along so that all that was needed to maximize extract from the malt was a single-temperature infusion mash. In contrast, US and European 2-row malts needed to go through a programmed schedule of gradually increasing temperatures to control both wort protein levels and to optimize extraction. Indeed, the process of decoction mashing, where the temperature increases are made by withdrawing a portion of the mash, boiling it and returning it to the main mash may well have arisen as a way to handle poorly-modified malts. That was then; modern pale malts are of much higher quality, and pretty much all well-modified enough to be converted by a single temperature infusion mash. But, programmed upward infusion is used by a number of brewers for brewing certain beers to reduce wort protein and to yield wort with somewhat different fermentability and therefore beer flavor profile. Some lager brewers still prefer to carry out a time-consuming decoction mash as they feel it produces a richer flavor, especially in something like a bock beer (read more about decoction mashing on page 73 of this issue). But in most cases you will get as good a result as you want by using a simple single temperature infusion, and I would recommend using this approach to all homebrewers unless your homebrew recipe specifically calls for a different mashing method.
So if they are both well-modified what then is the difference between pale malt and pale ale malt? Well, there may be slight flavor differences (read on), and even in maximum yields obtainable, but the latter are insignificant in practice. The main practical difference is principally that of color, with US 6-row and 2-row pale malts coming in at around 1.7–2.0 degrees Lovibond (°L), and UK pale malt at 2.5–3.5 °L. There is one other difference and that is in enzyme content, with US 6-row pale malt being the highest, US 2-row somewhat lower, and UK pale ale malt lower still. That is why 6-row pale can handle high levels of starchy adjuncts, but unless you plan to brew a high adjunct beer, we do not need to worry about the lower enzyme levels in 2-row and pale ale malt. With an all-malt beer these grains contain sufficient enzymes to achieve complete conversion in the mash, and to convert any residual starch, which may be present in specialty malts.
Exactly how much of these base malts you use in a particular beer depends upon a number of things, such as the alcoholic strength and what specialty malts may be needed for a particular style. Here I can deal only with strength, which is directly related to the yield you can get from the malt. So, what sort of yield can you expect from pale and pale ale malts? At a maximum (which means under ideal conditions) you will get an original gravity of 1.038–1.040 (9.5–10.0 °P) for the extract derived from 1 lb. (0.45 kg) of malt in one US gallon (3.8 L) of water. As you probably know, you will not get that sort of yield in practice, and BYO bases recipes on a brew house efficiency of 65%. That means that you can expect to get yields of 1.025–1.026 (6.3–6.6 °P) from one lb. in one gallon.
Here is an example: Let’s say you want to brew 5 gallons (19 L) of a beer with an original gravity of 1.050 (12.5 °P), which for simplicity will be brewed with only pale malt. Then you will need total gravity points of 5 x 50 = 250. But pale ale malt gives 1.026 SG/lb./gallon, so we shall need 250/26 = 9.6 lb. (4.4 kg) of this malt.
Floor Malting
There is another type of pale ale malt, which is malt that has been floor malted. Most malts are produced via a drum malting process, during which the raw barley is first steeped in water until it has absorbed the appropriate amount of moisture, and then allowed to germinate. The drum is rotated and the temperature and moisture level of its contents are carefully controlled to ensure uniform germination of the barley. Once germination has proceeded sufficiently far, the green malt is then kilned to dry it. In the case of pale and pale ale malts this is done over a lengthy period, with the temperature rising slowly up to a maximum of about 170–180 °F (77–82 °C), depending upon exactly what the maltster intends to achieve. Generally pale ale malt is kilned at a slightly higher temperature than pale malt, hence its higher color. The great advantage of drum malting systems is that it permits the maltster to control the whole process to produce a high quality, uniform product.
Floor malting is a much older, more traditional, process than drum malting, although at first sight it seems the same in that it involves the identical stages of steeping, germination and kilning. The big difference is that in the germination stage the steeped barley is spread in a thin layer (“couch”) on a floor. The germination has then to be controlled manually, in order to ensure uniform progress during growth. The big problem is temperature control, for considerable heat is generated by the germinating grain. This is done in two ways the first being by controlling atmospheric temperature by opening or closing louvered windows in the walls. The second way is by regular “turning” of the grain to ensure that hot spots do not develop in the bed. This is a totally manual process, carried out by men and/or women walking on the bed and turning it using wooden rakes and spades.
The main barley variety used in floor malting in Britain is Maris Otter, and with this the result is a plump rounded malt, perhaps a little darker in color than other pale ale malts at 3–4 °L. Opinions vary on its quality, but many brewers think that it adds a fuller, more rounded and even nuttier flavor to pale and bitter ales and IPAs than other pale ale malts.
Beyond the Pale
Now, I have largely talked about pale and pale ale malts in the context of pale beers, but they are also the base for nearly all kinds of beer, from pale lager to dark imperial stouts, and the question is whether it is always necessary to distinguish between them, or can they be considered as being interchangeable? It is partly a question of taste and some brewers would never use 2-row pale in a pale ale, or pale ale malt in a light lager. Others see 2-row malt as true workhorse and use it in every beer. Personally, I do not see the differences as being important in a beer brewed with a significant proportion of specialty malts. In other words, if the main flavor notes in the beer are caramel, biscuit, roasted and so on, these are going to dominate anything the base malts can supply, except for perhaps some body, which really comes from the mashing temperatures used. Therefore, in such beers you can use whatever base pale malt you prefer or happen to have on hand.
Pilsner Malt
This is a version of pale malt, but is lighter in color (1–2 °L) than those discussed earlier, and is slightly less modified than they are. Do not be fooled by that statement, for it is modified well enough to be used by a single-temperature infusion mash. And it will give about the same extract yield, 1.025–1.026 per lb. per gallon at our 65% brewhouse efficiency. It gives a lighter, crisper flavored beer than other pales, and as its name suggests is ideally suited to brewing Pilsner beers, in which it is the only malt used. There is generally no advantage to using this malt in any kind of fuller-flavored or darker beer since in those styles the characteristics the malt is designed to produce would be lost.
Mild Ale Malt
Mild ale malt is produced just as pale ale malts, but is kilned at a slightly higher temperature, and is therefore a little more colored at around 3.5–4.5 °L, but still has a sufficiency of enzymes for most malt bills. As with the others it will yield around 1.025–1.026 per lb. per gallon at 65%, and can be mashed by the single-temperature approach. It gives a roasty, slightly sweeter and fuller flavor than pale ale malt, and can be used to advantage in mild ales as you might expect. Mild ales, which start at a low gravity, can be very light, bland and even boring, but if this malt is used as the base they can be almost luscious and even nutty on the palate. Further, mild ales are often brewed with a proportion of roasted malt, whose harshness can easily make the beer unbalanced, and mild ale will nicely balance that. But there is no reason, apart from that of color, to limit use of this malt to mild ales for it works well as a base in many beers, especially in dark ones.
Vienna Malt
This is another malt kilned slightly more than the pale ale malts, which may be made from either European 2-row and US 6-row barleys. It is relatively high in color (3–5 °L), and gives a slightly lower yield than pale malts, namely 1.023–1.024 per lb. per gallon for our 65% efficiency. Like our other base malts it has a significant enzyme content and can be fully converted in a simple infusion mash, but it often does not have enough enzymes to handle starches from adjuncts or specialty malts. It was originally designed for brewing Vienna lagers, however, it can be used in other beers, such as IPA.
Munich Malt
This is the highest kilned malt in this range and it may be as high as 30 °L in color. However, I am talking about lower kilned versions, which come in at 8–11 °L. Munich malt does contain enzymes and can be infusion mashed, giving a yield similar to that of Vienna malt, of 1.023 per lb. per gallon. However, Munich is rarely used on its own, and I would recommend always using it in combination with a pale malt, so it is only a quasi-base malt. But it does add a toasty flavor in a beer, as well as providing some good mouthfeel. I use this malt in a lot of beers, especially in pale and bitter ales where I want a little more body and flavor than I can get by simply using the more “normal” pale ale malt/crystal malt combination.
