FG 1004 - wild yeast infection?

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Braufather

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latest brew was an american IPA with a 100% extra pale marris otter grain bill and wyeast smack pack american ale yeast.

OG spot on at 1054. but the target final Gravity should have been 1014 but i overshot by 10 and got 1004!

bottled now and keeping an eye on it, but before i do my next batch do i need to change my cleaning and sanitising regime- i understand star san isnt very effective against wild yeast ( and that makes sense).

is there a way to test equipment for presence of wild yeast?
 
ok time will tell. previosuly this yeast pack hits 1014 from 1054,so i was surprised!
 
What was your mash temperature and did it drop during the mash? You could've just made a very fermentable wort
 
Usual 65c. First time I've used extra pale malt though.

Interesting you should say that. I just used 81% maris otter extra pale in a recipe for the first time a few weeks ago.

Mashed at 66C and got an FG of 1.007 from WLP023 when the estimated was 1.011. Attenuation was 84.2% vs. the predicated of 74.5%.

I put it down to 2nd generation yeast attenuating higher (it happens) but now you mention extra pale I'm wondering if the malt had a higher diastic power than we usually get. Where did you get it from? Mine was from brewuk.
 
Usual 65c. First time I've used extra pale malt though.

I would not worry overly before tasting the final product. A wild yeast is going to be present in far too few numbers to cause an issue straight off. The yeast strains I use like US 05 and M31 (Belgian) will often get down to near that level.

If you started at more usual temps in the 18-20 or so range, then a weather event boosted the temps by a few degrees at the "right" time, then that could also account for it.

Plus, as I keep saying, your hydrometer is a guessing stick only. The better you know it and its limitations, the better the guess.
 
foxbat - got mine from geterbrewed as part of a build your own recipe kit.

Slid - fermented in brew fridge at 18C for 4 weeks, and it had reached 1005/6 by then if i recall correctly. I was going to bottle then but lost my stick so ended up transferring it to another fv to get it off the trub and by the time i got a new bottling stick and got round to it, it was another 4 weeks. and at 1004

also am i correct in thinking US05 is the same strain variant as wyeast american ale?
 
Interesting you should say that. I just used 81% maris otter extra pale in a recipe for the first time a few weeks ago.

Mashed at 66C and got an FG of 1.007 from WLP023 when the estimated was 1.011. Attenuation was 84.2% vs. the predicated of 74.5%.

I put it down to 2nd generation yeast attenuating higher (it happens) but now you mention extra pale I'm wondering if the malt had a higher diastic power than we usually get. Where did you get it from? Mine was from brewuk.
Well, interesting-er and interesting-er! My last brew was also made with Extra Pale Maris Otter 'cos I'd run out of the normal stuff. Went from 1.040 to 1.006 when I usually get a FG of 1.010 or so. I put it down to some higher temperatures fermenting (but only 22 rather than 19). I'll think again.

(Warminster malt, BrewUK)
 
This is all good. Optimistic now it's not wild yeast. Every day is a school day in brewing eh! I assumed yeast attenuation would be much more regular for branded yeasts.
 
65 is a tad lower than my usual 66-67c (66.7) target but if maintained not significantly so, or so i wouldn't have thought..

how does the brew taste, as long as its tasting good and not too thin watery and bodyless chalk it down to experience and have a pint ;)

edit also worth mentioning whenever you get an unexpected gravity reading check the hydrometer reads circa 1.000 in water, i once washed/sanitised a hydrometer in too hot a water bath and it melted the glue securing the grade tube in place so the tube would move up n down with a nudge or jolt rendering it useless..
 
Usual 65c. First time I've used extra pale malt though.

AjHutch question is important. 65 is mostly using Beta amylase. This enzyme will produce extremely fermentable sugars. That yeast will eat it all up. If you're looking for an ale with body and you're not recirculating mash, but rather a cool box mash tun, then you want to have a 67 to 68 degree mash. So your strike water, at this time of the year would be around 71 to 72 degrees.
From 66 degrees and up, the alpha amylase enzyme will start working. This enzyme produces more complex strains of sugars that many yeasts have a hard time breaking down. That's what gives it the body. But us-05 will still attack it really well.
 
i use a bm so the mash gets well circulated, and have always done IPAs/ PAs at 65C, following recipe guidlelines with one exception at 63C from the speidel website.

however I did notice that all the IPA recipes in BYO magazine pretty much went for 67C, so may give that a go next time.
 
Second batch with that Warminster Extra Pale Maris Otter. This one is an APA and mashed at 62C, but I still wasn't expecting it to get down to 1.004, and it is still going! This time the temperature is being controlled and is less than 18C (16C currently).

Even I might start panicking about "infection" if it carries on (if you've come across some of my past posts you'll know my bad attitude towards the tendency to cry "infection" when anything goes wrong these days).

(EDIT. Changed 1.006 to 1.004 - I'm obviously in denial about these low readings).
 
Let's stick a pickie to my last post. This is off Beersmith.

Temperature is a little erratic for Day 1 until I had the confidence to leave the controller to do its thing.

Capture.JPG
 
It'll be fine. Very dry but that's because of the very low mash temp. I wouldn't doubt if that batch goes almost to 1.001. Try to keep your mash around 67.
An infection would come off as super rank, or vinegar. Going real dry would be a wild yeast problem. But I highly doubt that's what happening. Because your mash was so low you've just created all fermentable sugar. If you don't mind the high alcohol content, you could boil some brown sugar, cool down then add it to your batch. The brown sugar will still ferment but not all of it. It might lift up your gravity a tad to give you some body. Just a thought.
 

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