wild yeast in my extract brew ?

[brewjohn]

my last couple of brews have been spoiled by what I assume to be wild yeast . The bottles were over carbonated and the insides of the bottles had a film clinging to the sides.as well as a loose powdery deposit at the bottom . I tried to tackle this and seemed to have failed again . I brew in a heated controlled fridge and cleaned all surfaces in and out with a bleach sotution. I decied to brew under air lock and used my 5 gal Richie wine fermenter with bottom tap . I made a 3.5 % ABV extract brew using a S04 yeast at 20 Deg C . It soon fermented and I decided to bottle with a short piece of tubing straight from the fermenter bottom tap so as not to transfer to another vessel. Its now over a week since it was botled and after inspecting one of the clear botles I filled I can now see signs of the infection again !! As Victor meldrew says " I dont believe it " . Is this the usual signs of a wild yeast ? What more can I do to get round this problem apart from turning down the fridge and using a Lager bottom fermenting yeast .

[EoinMag]

my last couple of brews have been spoiled by what I assume to be wild yeast . The bottles were over carbonated and the insides of the bottles had a film clinging to the sides.as well as a loose powdery deposit at the bottom . I tried to tackle this and seemed to have failed again . I brew in a heated controlled fridge and cleaned all surfaces in and out with a bleach sotution. I decied to brew under air lock and used my 5 gal Richie wine fermenter with bottom tap . I made a 3.5 % ABV extract brew using a S04 yeast at 20 Deg C . It soon fermented and I decided to bottle with a short piece of tubing straight from the fermenter bottom tap so as not to transfer to another vessel. Its now over a week since it was botled and after inspecting one of the clear botles I filled I can now see signs of the infection again !! As Victor meldrew says " I dont believe it " . Is this the usual signs of a wild yeast ? What more can I do to get round this problem apart from turning down the fridge and using a Lager bottom fermenting yeast .

You don't mention taste, can you taste an infection, because what you are describing could be anything. I've had yeast cling to the inside of bottles with no off-flavours.

[crafty john]

my last couple of brews have been spoiled by what I assume to be wild yeast . The bottles were over carbonated and the insides of the bottles had a film clinging to the sides.as well as a loose powdery deposit at the bottom . I tried to tackle this and seemed to have failed again . I brew in a heated controlled fridge and cleaned all surfaces in and out with a bleach sotution. I decied to brew under air lock and used my 5 gal Richie wine fermenter with bottom tap . I made a 3.5 % ABV extract brew using a S04 yeast at 20 Deg C . It soon fermented and I decided to bottle with a short piece of tubing straight from the fermenter bottom tap so as not to transfer to another vessel. Its now over a week since it was botled and after inspecting one of the clear botles I filled I can now see signs of the infection again !! As Victor meldrew says " I dont believe it " . Is this the usual signs of a wild yeast ? What more can I do to get round this problem apart from turning down the fridge and using a Lager bottom fermenting yeast .

You don't mention taste, can you taste an infection, because what you are describing could be anything. I've had yeast cling to the inside of bottles with no off-flavours.

Me too, but never with SO4. As EoinMag says, where there any off flavours?

[brewjohn]

It tastes far too dry and bitter .

[EoinMag]

It tastes far too dry and bitter .

OK that does sound like an infection then, some infections have an astringent taste.

What part of your process has been common to the last few brews? It can be a bitch finding the infection in a house infection, normal remedy is to change all your plastic out.

[brewjohn]

Thanks. the only thing in common is I brew in a heated fridge with a ATC 800 controller. I have tried two different fermenting bins. I wonder if the fridge could be hiding spores of wild yeast in nooks and crannies and needs more serious cleaning ? I cleaned the inside with bleach solution but might try the kitchen steam cleaner we have before another attempt.

[jmc]

What do you do to sanitise your FV?

[brewjohn]

I have tried both sodium metabisulphide in hot water and houshold bleach. Not tried Starstan yet but might do. Seems quite popular here.The siuation has got worse since fermenting in a fridge.?

[jmc]

I have tried both sodium metabisulphide in hot water and houshold bleach. Not tried Starstan yet but might do. Seems quite popular here.The siuation has got worse since fermenting in a fridge.?

If the fridge is infected then in may be a source, but I'd guess that its more likely that problem is somewhere in brewing process or sanitation regime you use.
eg Do you return hydrometer sample to brew? I don't to reduce chance of infection.

I think brewing lower alcohol brews in the summer is more challenging so there may be a problem there too.
3.5% is not that strong and so you'll have less protection from alcohol that's in a stronger 4%+ brew
And I just think there's more bugs in the air during the summer.

Maybe its just coincidence but the 2 brews I've had that went bad were both in the summer.

I don't think sodium metabisulphite will do for sanitising when brewing beer.
I don't think it will totally kill yeast, just inhibit it for a while. Bleach is good, as is heat.
Starsan is very good to. I use that myself, but remember sanitisers only work on perfectly clean kit.
Its essential all kit is perfectly clean before you sanitise

I'd be tempted do a deep clean & sanitise on FV, taps, tubing etc
a) Take apart what you can so no hidden crevices left unclean
b) Thorough clean & scrub FV etc (with soft sponge). I use oxy for this. Rinse after clean.
c) Soak taps and small items in dilute bleach solution; 10cc thin bleach/ 1L. then refit tap so you can fill FV. 20-30 min soak will do
d) Fill FV with dilute bleach solution 10cc thin bleach/ 1L. . 20-30 min soak will do. Prior to this some people scald the FV with boiling water from a kettle.
e) Rinse with clean water a couple of time. You can use your sod-met to remove any trace of chlorine from bleach. Its good at that.
f) Ready to brew - Keep FV sealed up and ready to brew and repeat d-e if its more than a few days before you brew.

Even if using starsan I'd still do a deep clean with bleach if you get an infection.
I use this method regularly for kit that I've used for lambics, saison, etc so that I kill off everything before next brew started.

[brewjohn]

Thanks for that very thorough reply. The contents have been noted. The reason I made a 3.5% brew was just to use up 2.5Kg of DME I had . Also to do a test to see if this one got infected as the others. As you say a stronger brew would have stood a better chance. Leyland home brew is just down the road from me and I notice they have a sanitizer called BREWPAK STAYCLEAN. does any one have any experience of using this ? If I fail again at least with the set up I have I can get the temp right down to very low in summer and use a botton fermenting yeast !

[EoinMag]

The temperature probe....is that going into the booze or is it taped to the side of the vessel?

[brewjohn]

it will be sanitized and into the brew. I once had it clamped to the outside and it fell off and ended up outside when I opened the door . When i checked several hours later the fridge was going continuous and the beer was allmost frozen !!!

[EoinMag]

it will be sanitized and into the brew. I once had it clamped to the outside and it fell off and ended up outside when I opened the door . When i checked several hours later the fridge was going continuous and the beer was allmost frozen !!!

Take care of that then, that sounds like it could be an issue.

[jmc]

it will be sanitized and into the brew. I once had it clamped to the outside and it fell off and ended up outside when I opened the door . When i checked several hours later the fridge was going continuous and the beer was allmost frozen !!!

Take care of that then, that sounds like it could be an issue.

+1

I use 6 inch length of duct tape covering a bit of foam (1.5 x1.5 x 0.5 cm).
Temp probe is held between foam and FV wall.
A thermowell would be better, but its on the long list of things to add.