Beer Forum

Hey all,
I brewed Jamil's Maibok last weekend. A very tasty brew it is too, having brewed it this time last year also. Anyway, just for fun, this time, I included a single decoction, rather than the infusion of the original.
Well, as the final completion time of the mash approached, I noticed that the wort was cloudy. Hmmm, perhaps it's not fully converted, so I left it another 30 minutes. Still cloudy. I went ahead and carried on and now the beer is probably 70% done fermenting...still cloudy.

I've brewed plently of batches and have my system down, never seen this before. I've even done the odd decoction before and never had this. My rests on the mash were at 131F and 156F. The decoction was about 6 L of thick mash, and I added more water to it to prevent scorching on the stove.

Grain bill was 5.5kg German pilsner and 2.4 kg munich.

Is this a starch haze? It's the only thing I can think of. If so, will it clear during lagering until May? Any ideas what part of the process (presumably related to the decoction) might have caused this?

Thanks for any ideas, awsome Army.

mickp wrote:I added more water to it to prevent scorching on the stove.

Is this a typical process for decotion? I haven't done one, but don't remember hearing about adding water during...

Well, it's not traditional, but is mentioned by Randy Mosher and perhaps others. If you get the thick part of the mash it makes the decoction heating/boiling much easier, less likely to burn.
Question is...would this cause haze?

I suspect it is a starch haze but can't really offer an explanation except to guess that in not resting at around 150 you didn't give beta amylase a chance to bust off maltose. I don't really like that explanation because even at 156 I'd expect some beta amylase activity and I'm sure the rest mash didn't go instantaneously from protein rest temp to 156.

Lots of people add some water to the decoction to thin it to make it more manageable, to prevent scorching and to make up for water loss in advance.

Thanks guys. It's still fermenting so we'll see what happens when I'm able to cool it way down. It's more a "murk" than a haze really, pretty turbid, but I guess it always looks worse in the carboy.

We can all slap ourselves on the forehead and exclaim "Doh!". While it's fermenting there are lots of yeast in suspension. See whether it drops clear at the conclusion of fermentation.

ajdelange wrote:We can all slap ourselves on the forehead and exclaim "Doh!". While it's fermenting there are lots of yeast in suspension. See whether it drops clear at the conclusion of fermentation.

Heh... I missed the "70%" part of the original post... guess he'll let us know!

Mick, compare the clarity of your 70% fermented beer to your wort. Was your wort more cloudy or less cloudy prior to pitching yeast? I would think with the hot and cold breaks most of the wort you transferred to your fermentation vessel should look clear for the most part unless you carried a lot of trub and hot matter with it.