Help Urgent! Yeast Problem

[hughyg]

Was just about to pitch my starter into a brew and noticeed a bit of a canned corn off aroma in the starter.. Its wyeast Thames Valley. Should I proceed??
Cheers
HG

 

[AndrewQLD]

was it an actively fermenting starter?

 

[AndrewQLD]

I have smelt corn in a starter before but the starter never actualy started so the corn smell was just warm stale wort.

 

[hughyg]

it was a very active starter.

 

[AndrewQLD]

to be honest, the yeast might well be fine, but I am a bit anal about my yeast starters and if I am even slightly uncertain I chuck them. Have a look at the wyeast site maybe there is some info there.

Sorry for the lack of help.

Cheers
Andrew

 

[Hopeye]

When in doubt, chuck it out and use the old dry yeast standby. If you don't have any old dry yeast standby then start panicking and call whoever you know.

 

[Linz]

or use the "No chill method" till you get a yeast........

 

[Aaron]

I would guess you had a lid on while boiling up your starter or put a lid on it after you boiled whilst waiting for it to cool. That can cause you to get that aroma into a wort/starter. I get that in my starters from time to time.

 

[hughyg]

shall I use it aaron? do you?

 

[Mr Bond]

I would guess you had a lid on while boiling up your starter or put a lid on it after you boiled whilst waiting for it to cool. That can cause you to get that aroma into a wort/starter. I get that in my starters from time to time.

[post="122546"][/post]​

You mean like DMS?

 

[hughyg]

DMS-like not overly strong though, but definately there

 

[BlueJ]

I know nothing about this other than that which Google has kindly found for me to read. But what Google has found is pretty interesting.

From http://www.homebrewzone.com/homebrewglossary.htm

Dimethyl Sulfide (DMS) causes the canned corn / vegetable aroma and flavours.

From Wikipedia http://en.wikipedia.org/wiki/Dimethyl_sulfide

DMS is an indication of bacterial infection in malt production and brewing.

 

[JLB]

I recently had 3068 hefe strain smell like canned corn and thought id risk it and give it a go
BIG mistake the fermenting had stalled and the beer was left tasting off :blink: tossed the lot
choice is yours if your feeling lucky

 

[hughyg]

I decided to go ahead and pitch it. It was my first ever partial so I really hope it wasn't contaminated, and it was just me stressing.

 

[Aaron]

Yes, I believe it is DMS. I get it in my starters and use them. I don't know if it is the right thing to do but I have not had any negative consequences that I have noticed.

 

[hughyg]

could it be due to closing the lid on the hot malt starter? like a by-product?

 

[Fingerlickin_B]

Although I don't know why I will answer "yes", as I've read never to let the condensation back into your boil and as such I never use a lid.

I'm sure someone else can tell you why...I just run off what I've read not to do

PZ.

*spelling edit *

 

[Aaron]

could it be due to closing the lid on the hot malt starter? like a by-product?

[post="122588"][/post]​

I think that is what causes it. I get that smell when I cool my starters in a pot with the lid on. As far exactly what i going on. I can't help with that. You should be able to find some info on AHB or through Google.

 

[BlueJ]

Please keep us informed of progress? I will be getting around to keeping yeast starters in the fridge eventually. I would really be freaked out if the starter smelt off, with a fermenter full of goodies just waiting for yeast to be added.

The DMS is a telltale for a bacterial infection, so the questions are
1) level of DMS?
2) are the bacteria still viable?

If the bacteria are no longer living, then let's assume you can smell DMS in 100ml of starter. If the starter is diluted 200:1 by putting it into a 20l brew, is the DMS still detectable? The brew may be a goer.

As a friend once told me, 'dilution is the solution to pollution'.

If the bacteria are still living, then I guess you will throw it out after a few days. Let us know?

 

[barfridge]

I've noticed DMS in thames valley yeast before, but it's never been a problem in the finished product, as it's easily boiled off.