How to Vorlauf Cold Brew: Filter It Through Its Own Coffee Grounds

Vorlaufing cold brew means pouring the first cloudy coffee that drains from your brewer back over the spent grounds. The coffee bed then filters out the fines. It adds a few minutes at the end of the steep and costs nothing. And it can get you clear cold brew without a second paper filter. I’ve vorlaufed cold brew before kegging it ever since I started brewing it in 10+ gallon batches. Years later, I still rarely hear anyone in the coffee world talk about it. Homebrewers will know the term right away. If you’re coming from the coffee side, here’s what it is, when to do it, and how.

What Is Vorlauf?

Vorlauf is a German brewing term that translates roughly to “run ahead.” In practice, it means recirculation. In beer brewing, small bits of grain stay suspended under the false bottom after the mash rest. Brewers drain that cloudy wort and send it back over the top of the grain bed, which acts as a filter. As The Oxford Companion to Beer (edited by Garrett Oliver) puts it, “Brewers continue the vorlauf until the recirculating wort runs clear.” Cold brew has the same problem. No matter which filter you use, tiny coffee particles called fines get through, around, or under it. In a Cold Brew Avenue cold brew system, for example, some fines pass the fine mesh screen and settle beneath the filter plate. Instead of sending that coffee straight to a keg, you can vorlauf it. Recirculate it back onto the bed of grounds, and most of the fines get caught.

When to Vorlauf Cold Brew

Vorlauf once the steep is finished and before the cold brew goes anywhere else. In beer brewing, the vorlauf comes at the end of the mash rest. In cold brew, it comes at the end of your steep, whether that’s 5, 12 or 24 hours. Steep time is your call, and so is whether you vorlauf at all.

How to Vorlauf Cold Brew, Step by Step

These steps assume a stainless steel brewer with a filter plate or screen and a drain valve at the bottom. The same idea works with any brewer that drains from below a settled bed of grounds. You can recirculate by hand or with a pump.

Option A: Recirculate by Hand

This is the simplest way to start, and all you need is a sanitized pitcher or bucket.

1. 1. Finish the steep and leave the bed alone. Don’t stir or press the grounds. A settled bed filters best.

1. 1. Drain the first runnings slowly. Crack the valve and run the coffee into a clean, sanitized pitcher or bucket. This first coffee is the cloudiest, since it carries the fines that collected under the filter.

1. 1. Pour it back gently over the top. Spread it across the surface of the grounds so you don’t dig a channel into the bed.

1. 1. Repeat until it runs clear. After each pass, pour a sample into a clear glass and hold it up to the light. When a fresh sample looks as clear as the last one, you’re done.

1. 1. Transfer to kegs or bottles. Keep the flow slow and steady so the bed stays undisturbed through the last of the draining.

Option B: Use a Recirculation Pump

On bigger batches, a food-safe recirculation pump saves you a lot of pouring. The key is keeping the flow gentle. Pull too hard and you’ll compact the bed or drag fines right back through it.

1. 1. Finish the steep and leave the bed alone. Same as Option A: no stirring, no pressing.

1. 1. Connect the pump to the brewer’s outlet. Run food-safe tubing from the outlet to the pump’s inlet. Then run a return hose from the pump’s outlet back up to the top of the brewer.

1. 1. Keep the flow slow. If your pump speed is variable, run it at a low speed. If it isn’t, throttle the flow with the dump valve. Don’t open it all the way. Open it 10-25%, depending on how strong your pump is.

1. 1. Return the coffee gently. Rest the end of the return hose just above the grounds so the coffee spreads across the bed instead of digging a channel.

1. 1. Recirculate until it runs clear. Pull a sample into a clear glass from time to time. When a fresh sample looks as clear as the last one, you’re done.

1. 1. Shut off the pump and transfer. Move the return hose to your keg, or disconnect the pump and drain slowly, so the bed stays undisturbed.

One caution from the brewing side: sending fines back into the bed can slow the drain. The Oxford Companion notes that some brewers skip the vorlauf for exactly that reason. If your runoff slows to a crawl, close the valve down a bit and resist the urge to stir. The bed will keep doing its job.

Benefits of Vorlaufing Cold Brew

Vorlaufing turns your spent grounds into a filter. Fines poured back on top mostly work their way into the bed and stay there, instead of ending up in your keg. You can see the difference without vorlaufing at all. Pull a cup right when you open the valve and set it aside, then pull another at the very end of the drain. The first cup is almost always noticeably cloudier, because it carries most of the fines that got past the filter. When I started vorlaufing those 10+ gallon batches, I tracked the results in a brew journal. My notes showed roughly two-thirds of the settled sediment staying in the bed instead of reaching the keg. That journal is long gone, so treat the number as a ballpark from my own batches, not a lab result. The two-cup test lets you check it on your setup.

• • Clarity: less sediment means cleaner cold brew, often without a secondary filter.

• • Flavor that lasts: cold brew that isn’t sitting on a layer of fines in the keg or bottle tends to hold its flavor profile longer.

• • Yield: you may see a slightly higher yield, since the recirculated coffee passes back through the grounds.

• • Fewer steps and less waste: skipping secondary filtration saves time and the cost of disposable filters.

Vorlauf vs. Paper and Composite Filters

There’s no single best way to filter cold brew. It comes down to how clear you want it, how much body you want to keep, and how much waste you’re willing to create.

	Vorlauf with a reusable stainless filter	Paper or composite filter
Clarity	Clear once it runs clear; a trace of very fine sediment is possible	Clearest; removes even the finest sediment
Body and oils	Keeps the coffee’s oils for a fuller, richer cup	Traps some oils for a cleaner, brighter finish that can taste slightly muted
Waste and ongoing cost	None; the filter is reused batch after batch	New filters every batch
Extra work	A few minutes of recirculating	Changing and disposing of filters
Best for	Large batches going into kegs, low-waste setups	Maximum clarity, brewing anywhere (even in a bucket)

If your stainless filter already gives you the clarity and flavor you want, the gain from vorlaufing may be subtle. For kegged cold brew, I’d vorlauf first. Only add paper if the two-cup test still shows more sediment than you want.

Vorlauf Cold Brew FAQ

Does vorlaufing replace a paper filter?

Often, yes. For most kegged cold brew, a good stainless filter plus a vorlauf gets clear enough that a second filter isn’t needed. If you want the absolute clearest cup, you can still run it through paper afterward, and the paper will clog far less.

How many passes does it take?

There’s no fixed number. Keep recirculating until a fresh sample in a clear glass looks as clear as the one before it.

Can I vorlauf with a mesh bag or immersion brewer?

Vorlauf works best when coffee drains from below a settled bed of grounds, like a brewer with a filter plate and bottom valve. A bag doesn’t give you a bed to pour through, so a secondary filter ends up doing more of the work.

Does vorlaufing change the flavor?

Not the way paper does. It removes sediment without stripping the coffee’s oils, so the flavor stays close to what came out of the steep, just cleaner.

Next Steps

New to cold brew? Start with making cold brew coffee at home, or read our guide to cold brew and serving coffee on draft. Once your cold brew runs clear, it’s ready to keg. Our cold brew kegs keep it sealed and cold, and a cold brew or nitro draft kit puts it on tap. Photo by Jacob Bentzinger on Unsplash