Less trub with AG?

Something I've noticed recently is that I've been getting way less trub in the fermenter since switching to AG. I dump the whole kettle into the fermenter.

For comparison, my extract nut brown and IPA brews from last month had up to 0.5 gallons of trub - I just barely got my 48 bottles and that's fine but I usually end up with a few extra for early tasting. My AG brown ale / failed bragot (with twice as much grain as the extract nut brown) has maybe a quarter inch of trub while a recent Scottish ale is looking very nice as well.

I've only got one bazooka screen and I batch sparge. The bazooka screen was in the mash tun for AG (I dump the cooler and move the screen to the kettle, when I remember) and in the kettle for the extracts.

I mean, as with all things, YMMV. But does anyone else notice this as well?

Yes, I noticed that when I switched to AG. My guess is when doing extract, a lot of the trub comes from the steeping grains.

I think the reason for less trub in AG batches has to do with the vorlauf. When steeping specialty grains this step is skipped leading to more particles ending up in the boil kettle.

unionrdr said:

By that logic pm & ag should have more,not less. When I do a finer crush for biab partial mash,I get a lil more trub from the real fine floury stuff that can't be strained out. But that compacts pretty wll,so I easily get my 48 bottles. Got 51 bottles last Saturday. And that one started with 1L of trub & cold break. It cpmpresses down to 1/3 that mass in 4 weeks.

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Not necessarily, if you vorlauf properly the fine partials will be filtered by the grain bed so you should end up with less trub in the fermenter. If you are using a bag an pulling it all of the fine partials will stay in the wort and then into the fermenter where the drop out.

A pumpkin ale would be the ultimate test for this.


I think the vorlaufing has a pretty big effect. There might also be some contribution by hops due to cold/hot break that causes the styles to vary in a way I overlooked. If I read correctly, more hops = more break.

That'd explain the IPA trub levels - though I did filter them in a mesh bag after passing through a bazooka screen. (I was filling entire mesh bags with the break material.) Still a ton of junk in the fermenter.

The brown ales (extract vs AG) are telling though. They were both mostly biscuit malt, recipes from Radical Brewing (is it me or does Randy Mosher love biscuit malt?) with very little hops.

Do gelatin finings help compact trub at all?