Denny's Batch Sparge Method Viable Commercially?

Is there a specific reason that larger breweries don’t batch sparge and why they recirculate the mash or use heated tuns to maintain temp rather than just using an insulated vessel?

It seems like it would be pretty doable for nanobreweries, which could essentially be scaled up homebrew systems, but how about the bigger guys? For that matter, why do I see a lot of the nanos I visit using the using the more complicated systems rather than Denny’s simple system? To me, the simpler the technique, the more consistant the results with fewer problems. In this case, it’d be cheaper too.

Efficiency and ease. Pro breweries like to maximize their efficiency. And I’m sure batch sparging would be a lot more difficult with such a massive amount of water. There are hybrid versions I’m sure on the smaller scale.

Mash tun and grain costs would be the main reasons I think - you can get a lot of wort out of a relatively small mashtun, fly-sparging, with a very high yield. If you wanted to go with a batch-sparge system professionally, you’d probably need to parti-gyle and produce 2-3 worts from every mash.

Actually, I just read a post by Horst Dornbusch on the BA Forum about German breweries batch sparging. who would have thought! I’ll try to find it and repost.

Here it is…

In a conventional German brewing schedule, after mashing in in the kettle and pumping the mash over for lautering ("Abläutern), you would lauter recirulate as we do (“Vorlauf”), and then lauter until the mash is virtually drained, while NOT adding brewing liquor during lautering. That run-off is the “Hauptguss” (literally “main pour”). Then you have a “Nachguss” (literally “after pour”) or two, almost similar to the old British parti-gyle technique. The Nachguss is in one big shot, not by steady sprinkle.

This brew house configuration stems from the tradition of decoction: You mash in in the kettle, send two-thirds of the mash via slurry pump (or bucket ladle in the Middle Ages) into the lauter tun (or you send one-third of the mash into a separate cooker), and you boil the decoction. You pull the main mash back into the kettle (or the decocted portion from the cooker) for the next temperature step. Repeat as often as you wish. Finally you transfer the entire very hot mash via slurry pump to the lauter tun for Abläutern. Maintaining a steady mash temperature during Abläutern after decoction would be less essential, because conversion and dissolution of extractable particulate would be complete already. Also, if you use the lauter tun to hold the main mash while you decoct a portion of the mash in the kettle, thermal losses would be minimal, because the lauter tun would already be hot.

As you can see, if you wish to mash in in the lauter tun (especially for a multi-step mash) and then achieve the mash-out temperature through (instead of before) sparging (which the German call “Überschwänzen”), you need to specify the hardware features that would let you do that.

You may have thought about these features yourself. If not, perhaps the above might help. It is based on my experience. I once tried to make an ale “our” way in Germany in a top-notch system that lacked a heat source for the lauter tun. Also, there was no lauter tun device for a slow and steady sparge. My mash temperature dropped during lautering from around 170 °F to almost 140 °F; and the extract efficiency of that batch was below 55% even though that system is capable of producing German-style beers at an extract efficiency of about 75%. That’s a result you want to avoid in a production ale brew house!

Wow, he mashed at 170*? Dang. And 75% efficiency is the norm, huh?

Since he said “during the lauter” that may be a mashout temp he was starting at.

So is the idea that to hit a certain OG they fly sparge until they have the correct volume at the correct gravity? My understanding was that batch sparging, done properly, could get pretty darn close or equivalent efficiency to fly sparging, given the same quantity of water.

[quote=“blizzardofoz63”]So is the idea that to hit a certain OG they fly sparge until they have the correct volume at the correct gravity? My understanding was that batch sparging, done properly, could get pretty darn close or equivalent efficiency to fly sparging, given the same quantity of water.[/quote]Yes, that’s how fly-sparging works - you run water through the grain until you hit a certain volume or the gravity drops below a certain gravity (seems like 1.010 is commonly quoted). And yes, you can get efficiency comparable to fly-sparging from a batch-sparge, but you would need to set up the commercial brewhouse a bit differently - you could do it if you replaced the sparge rig (or supplemented in case you wanted to switch methods) to something that would allow rapid filling of the mashtun, used a modified false bottom or some sort of braid that would allow for a quicker vorlauf (or not, if you don’t care about time), and did two sparges in order to keep the mashtun volume smaller (and cheaper).