off flavours

[dean fisher]

hi all, last three batches have all had a grassy/ musty off flavour all different recipes and the only thing in common is the sack of glad fields malt that I brought. I still have the gains in the sack and am storing them in the spare room so I wouldn't think they would be getting damp or anything like that. I have found a few spots of mould in my brew room would this be causing it?

[oliver]

Bugger, that's no good. How does the grain taste when you chew it? Is it nice and crunchy? What type of malt is it and long did you boil for and how fast did you cool?

[dean fisher]

grain taste fresh when chew it crunchy as and it's just glad fields pale malt boiled for both 60and 90 mins depending on recipe and chilled in straight from kettle to fermenter in one pass thru big plate chiller

[Ralph]

The only thing in common? Were you using the same fermentor? Could it be an infection somewhere in the fermentor that is not being cleaned out? If it is a plastic fermentor with a tap near the bottom then check that you are taking the tap apart.

Mould in the brew room will mean your brew is more likely to get an infection as there will be spores floating around. Get some dilute bleach in a spray and give it a clean.

If the malt tastes fine when chewing on it, then I would think it is more likely to be a something in your brew process.

Can you give us a bit more information? I take it you do all grain - are you BIAB or using a mash tun? Did you check the pH of the mash, how do you cool your wort and how long does it take, are you reusing yeast, making a starter or just sprinkling dry yeast straight in. What are you using to clean the fermentor, what do you use to sanitise the fermentor. Are you bottling or legging?

[dean fisher]

Hi I have been using 2 different fermentor and I have a large plate chiller chilling in about 5 minutes. Using 3 vessel with mash tun. Brew kit cleaned with oxyclean and sanitised with starsan. ferment in A temp control fridge. I have been using us05 yeast for all these batches and have all been fresh packets. Only thing I can put it down to is mould spores in the room will try give a clean with bleach tonight

[Ralph]

Ah, sounds like you  have it sorted. Are you breaking down the plate chiller to clean it?

Gladfields pale malt can tend to have a high pH when mashing - which may contribute to the change in flavour? Probably worth checking the pH of the mash as well?

[dean fisher]

I'm breaking the chiller down and scrubing plates every 4 to 5 batches other wise running oxyclean then boiling water followed by star san must be just the mould in the room. Pisses you off when it's the third batch in a row will try running bleach over the wall and see what that does

[oliver]

Looking back at your flavour descriptor: grassy/musty brings hops to mind. Did you use a decent amount of hops in any of these beers? If so did you dry hop and how long for and at what temp?

[dean fisher]

One was a American Amber ale using all amarillos with 50g total it is a repeat brew and didn't taste off the first time. One was a IPA using NZ cascade dry hopped with NZ cascade as we'll total hops 300 gand one was a citra smash total hops 125 g

[oliver]

Cool, how long did you have the dry hops in for? 
Also how did the hops smell in the bag? The telltale signs for me are cheese + cardboard - if you smell any of either then the hops are no good.

[dean fisher]

All fermented at 18 degrees give or take and 3 week primary then into keg for carb

[Peter Smith]

I would tear it all down and give everything a good soak in cleaner then sanitiser, then do two quick batches, one smash with golden promise first then a existing gladfields smash

simple smash beers about 5% with clean nz hops, no dry hop.

I would go mot and riwaka but what ever, get new hops from a difference source.

In 10-14 days you will know if you have cured it, consider syphon hose replacement etc   got to think anything involved in transfer process could be infected.

[Peter Smith]

http://qhrumphf.tumblr.com/page/15

2,4,6-trichloroanisole. I’ve never smelled or tasted this in beer before. It’s a “musty” character that can apparently come from stale or improperly stored ingredients. It’s one of the worst things I’ve smelled or tasted in a beer. Like licking the floor of a basement after a flood. It lingered, and was just bloody awful.

Keen to know how your cleanup goes and if next brew is ok?