In part one and part two of our mash tun design series, John taught us about mash tun containers and methods of draining your wort. In part three of our mash tun design series, John will give us the lowdown on the different methods of sparging (rinsing) your grain. While this is more of a technique than a design consideration, you should think about which method you will be using most often when you design your mash tun, as certain shapes/styles work better with different sparging methods.
There’s three basic methods of sparging that we’ll cover. Fly Sparge, Batch Sparge, and No Sparge.
Fly sparging is a method of sparging where you pour water onto the top of the grain bed at approximately the same rate you take it off at the bottom. That way, you keep a constant liquid level in the tun and the water should move slowly –vertically – down the grain bed picking up all the good sugary bits on the way without channeling or whizzing past the grain too fast to pick up anything.
Fly sparging is what the pro’s do. And, generally, I think we homebrewers should try to adopt their best practices. But, the pro’s fly sparge for a different reason that we – I think – would. Fly sparging is the best way to make sure that you have rinsed absolutely every gram of sugar out of the grain and control your runnings very accurately. In this way, the professional breweries maximize their grain extraction without over sparging (see discussion later on). For homebrewers though, we’re not as concerned about extract efficiency – or at least we shouldn’t be. If I think my extraction efficiency is low and I’m not getting the right running coming off my tun, I can add an extra pound or two of grain and make up the difference. It might cost me $2 or $3, but that’s not a big deal. However, you scale that up for a 30 bbl batch, you’re talking hundreds of dollars more in grain for the professional brewer (“Sorry Honey, you and the kids can’t eat this week because I needed to throw some extra grain in a batch. But, hey! No big deal, right?”). So the professional brewers fly sparge to maximize their efficiency so they can keep their costs low (and afford to eat).
Fly sparging allows you to carefully control the rate at which you rinse the grain and that variable can influence the final beer’s body, mouthfeel, and taste perceptions. There’s a lot of information out there on fly sparging and some great gadgets to help you get it done without too much hassle. If you don’t have the fancy-schmancy gadget(s), you can still fly sparge and get great results, you might just have to do a little extra babysitting during the sparge.
When I started homebrewing, everyone fly sparged. Batch sparging was tantamount to Neanderthals banging on typewriters hoping to accidentally type out the game coding for Legend of Zelda (am I dating myself here?).
Anyway, we’ve come a long way in our understanding of what we’re actually trying to get out the sparge and why the professional brewers do it that way – rather than just mimicking them (see above). One of the great proponents of batch sparging is the Great Denny Conn (see his website below). Denny does a great job of explaining why he batch sparges, so I won’t rehash that here.
In batch sparging, after mashing, drain the mash tun – there’s your first batch of sparge to your kettle. put in fresh water into the tun and stir (or not, really). Let the grain settle again, drain the mash tun – there’s your second batch of sparge to your kettle. Repeat. You may do this process up to 4 or 5 times depending on how much you’re trying to rinse out of the grain bed. Be careful not to over sparge (see below).
What I will say is that it is dead simple. If you’re new to all grain, I highly recommend batch sparging. It’s less to worry about, harder to screw up, and gives really good results with very little added cost.
Ok, so this is just what it sounds like. You mash the grains, drain off the water, and that’s it. Whatever you had in the mash tun, that’s your pre-boil wort. The upshot is that this is really simple. If batch sparging is “dead simple,” this is “dead-er simple.”
Also, we know that the first runnings from the mash carry some not-grain/not-starch/not-sugar other stuff – you know, the stuff that gives the beer flavor! – that aren’t in the subsequent runnings. No sparge beers tend to feel “fuller” in body as well as “smoother” and “rounder” relative to the same beer using batch or fly sparging. Makes sense – all you have is first runnings going into the kettle when you “no sparge.” Barleywines are a great candidate for no sparge.
But – and there’s always a… well, nevermind – no sparge brewing reduces your ability to extract all the sugary goodies from the grain bed, after all you’re just draining it, you’re not even rinsing it once! That means that you’ll need proportionately more grain for the same beer than if you sparged the grain bed. Most brewing software will do this calculation for your or, at least, give you the tools to figure out how much more grain you need to get the same pre-boil gravity. Barleywines – with that full, round flavor – are great candidates for no sparge from the standpoint of the beer body, but the pocketbook will take a hit on this – you may need as much as 30-50% more grain to get the same pre-boil gravity, on big beers that gets expensive fast.
I kind of cheated and put it in earlier, but I’ll say it again: if you’re new to all grain, batch sparging it the way to go. Check out Denny’s website and The Brewing Network’s Sunday Session episode on “Pragmatic Brewing” (includes an interview with Denny) to find out details and tips/tricks.
I thought I’d throw in another couple of things I learned about sparging that may seem simple when you read them, but are painfully easy to overlook.
First: Over Sparging. Over sparging is when you’ve already rinsed out most or all of the sugars from the grain bed and you keep going anyway. When you over sparge two bad things happen – (1) you extract tannins and (2) you lower the gravity of your beer. As I mentioned earlier, the other stuff that makes beer wonderful (the not-grain/not-sugar/etc.) tends to be rinsed out first along with a big fraction of the total sugar available in the grain bed. With each pass through the grain bed, the water picks up less and less sugar. After you’ve rinsed out the good stuff and the sugar, what else can you rinse out? The bad stuff. You start to pick up an increasing fraction of tannins from the grain husks in the sparge water. This leads to a “tanic” bitterness and some amount of astringency in your beer that doesn’t get broken down in the boil and takes a long while – if ever – to mellow over time. Also, once you’ve rinsed most of the sugar out of the grain bed, that means that your sparge water is mostly… water. Unless you’re pre-boil gravity is already to high, you probably don’t want to water down your beer by adding more water. If you do, it’s water that you’ll have to boil off again to get your gravity back where you want it. So, watch out not to over sparge your mash. Best way to avoid it? Take gravity readings of your runnings from the mash run during the sparge. Once you hit ~1.010, stop. If you keep sparging past 1.010, you’re probably doing more harm than good.
Second: Channeling. The best way, in my mind, to avoid channeling is to have a uniform grain bed with no dough-balls (from un-wetted grain) where all the grain is mixed homogenously (no big blobs of all crystal malt or all dark malt). The grain bed should be a uniform consistency and appearance. Additionally, I always try to keep a liquid level in the mash tun above the grain bed. That is, I have enough water in the tun to cover the grain and maybe 1-2 inches more. That way, as I sparge, the sparge water doesn’t drill a hole in grain bed or cause too much of the grain to shift, the surface of the water absorbs most of that energy from the falling sparge water. It also helps to distribute the sparge water over the surface of the grain bed. Don’t use one stream of sparge water pointed into the middle or side of the grain bed. Use a spray nozzle or distributor plate to spray or dribble the sparge water over the grain bed surface – I’ve found that my crappy plastic false bottom I made works great for this!
I hope this helps you in your mash tun trials. In some of the next weeks we’ll be talking about maintaining temperature in the mash tun and cleaning. Thanks!