Like most homebrewers, I started out using the standard “malt extract with steeping grains” method of homebrewing. I can remember making a “pale ale” with two cans of liquid malt extract, a pound of crystal malt, and 2 oz. (60 g) of Cascade hops.
Later, I switched to all-grain brewing and was a bit of a purist for many years, only brewing all-grain batches. After all, my beers got markedly better when I switched to all-grain, why go back to an inferior method? Years later, I realized that it wasn’t the switch to all-grain that made better beers, it was all the other things I started doing at that same time. For example, I started making yeast starters. I started to evaluate my brewing ingredients and not brewing with stale malt or cheesy hops. And I started learning more about the science of brewing.
Several years after that, the method of adding malt extract late in the boil became popular, solving one of the biggest problems of extract brewing. Boiling a couple gallons of wort on a stovetop, in order to yield 5.0 gallons (19 L) of beer in the fermenter, often produced wort that was too dark. Adding the extract late in the boil solved that problem. Shorter boil times when the wort was at its densest lead to less color pickup. At that point, I decided to test a couple recipes using the “extract late” method of wort production. And they turned out pretty good, except for one thing. The recipes were mostly to check out new hop varieties (at a time when many old favorite hop varieties where scarce), and so the beers were mostly pale and had only a small amount of steeped grains. Their biggest drawback was the low amount of malt aroma.
Not too long after that, I tried partial mashing. In the next set of articles I post, I’m going to discuss partial mashing and advocate for it a little. As an “intermediate” between extract and all-grain brewing, it has its strengths and weaknesses, and I think most brewers would benefit from keeping it in mind as an alternate method.
Partial mashing is a great alternative method of homebrewing. For an all-grain brewer, it offers the ability to brew a batch of beer inside (if you normally brew outside), and the quality of the beer is indistinguishable from all-grain. For the extract brewer, conducting a partial mash is not substantially more difficult than steeping specialty grains, and the malt aroma of your beers will improve.
Partial Mashing for All-Grain Brewers
If you’re an all-grain brewer, you’re probably going to stick with that as your primary method of making beer. All-grain brewing is very versatile. For example, there are far more base grains available than types of malt extract, and you have the ability to use starchy adjuncts in the mash. It also gives you control over the fermentability of your wort. And finally, once you’ve acquired your equipment, your per-batch cost is lower than with extract.
However, if you like having options, partial mashing is a great standby method. You can still use any base grain you want in your recipe formulation, you can use limited amounts of starchy adjuncts, and you can still control the fermentability of your wort. (More on that in the extract section of this article.) Partial mashing will let you brew almost any beer you can brew using all-grain methods, but without braving the extreme heat of a southern summer or extreme cold of a northern winter.
Partial Mashing for Extract Brewers
If you’ve been brewing by steeping specialty grains and dissolving malt extract to make your wort, you can up your game by simply adding some base malts to your extract recipes, converting them to a partial mash formulation. The mechanics of brewing using a small partial mash are the same as with steeping specialty grains. The only difference is you have narrower “windows” for the temperature and liquid-to-grain ratios. The addition of base malt to your steeped grains adds the aroma of malt to your beer. The partial mash also allows you some degree of control over the fermentability of your wort. Wort made from a mash tends to be more fermentable than wort made from dissolving malt extract. If you have a particular beer you want to make with a drier finish, there are two ways that partial mash brewing can make your wort more fermentable. The first is simply by dilution; by mashing to make very fermentable wort or by increasing the amount of wort made from grains vs. extract, you can dilute the (less fermentable) wort made from extract with (more fermentable) wort from your mash. Secondly, you can dissolve malt extract into wort made from a mash, and let the enzymes from that wort work on the extract wort. And if you want the opposite — a very full-bodied beer — just do the opposite. Specifically, mash for a less fermentable wort and use a greater percentage of malt extract (although retaining enough base malts to still add base malt aroma to your beer).
Another good thing about partial mashing is that it is slightly cheaper than brewing straight extract beers, as malted grains are cheaper than malt extract made from malted grains.
In my next few articles for Beer & Wine Journal, I’ll cover how to convert recipes (both extract and all-grain) to partial mash formulations and give a few example recipes that show off the strengths and versatility of partial mash brewing. See the articles listed below for more information on the basics of partial mashing.
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