Funky smell 25 litres down the drain

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dafbach

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Hi guys.

A week ago I made a simple London Bitter using only maris otter and some crystal malt.

Equipment used was the Ace microbrewery. After mashing for an hour at 66C (as the recipe requested) I mashed out at 75C for 10 mins and sparged with water at approx 75C.

Due to being called out I then left the wort to cool down for a couple of days before resuming. Upon lifting the lid I detected a very clear funky odour, not too dissimilar to soured milk. I boiled the wort for 60 mins cooled and pitched the yeast.

3 days later the funky smell is still within the beer and so I discarded 25 litres!

Now, this is where it gets a little strange. My refuse was being collected today and the spent grains were placed in our garden recycling. Upon opening the lid I could clearly smell the same funky odour coming from the bin which contained the spent grain!

Initially I though it was the cooling of the wort that caused the odour, but it would appear that is was also within the spent grains!

Has anyone had a similar experience or may be able to tell me what has gone so wrong. This was my 14th brew using the Ace. Prior to mashing I had treated my water with 1 x campden tablet shared between the mash and sparge water.

Thank you in advance
 
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What is a funky smell?

If the grain and liquid smelt the same I would be less inclined to say an infection or wild yeast, perhaps it was meant to smell like that.

Leaving the liquid for a few days might mean wild yeast infection. You could have kept it and seen what it fermented out like
 
Grains are home to numerous bacteria and wild yeast. In the wort they had free reign to multiply an consume sugar in the 2 days before boiling, as did the bacteria and yeast on the discarded grains that didn't get boiled. The most basic function of the boil is to sterilise the wort in prior to performing a controlled fermentation with a known yeast.
 
What is a funky smell?

If the grain and liquid smelt the same I would be less inclined to say an infection or wild yeast, perhaps it was meant to smell like that.

Leaving the liquid for a few days might mean wild yeast infection. You could have kept it and seen what it fermented out like

I've just stuck my head in the bin and the first thing that comes to mind is soured milk.

I left it to ferment for a few days and if anything it was getting worse. I even placed a sample in the fridge to chill.
 
I suspect your wort and spent grains (with residual wort) were infected in the same way. In most cases the funkyness taints the beer even after boiling the wort. Like you, I left wort un-boiled for a period once, but did ferment and bottle. Wasn't worth the effort!
 
I've just stuck my head in the bin and the first thing that comes to mind is soured milk.

I left it to ferment for a few days and if anything it was getting worse. I even placed a sample in the fridge to chill.

Sour milk, most likely Lactobacillus bacteria, the most common bacteria in grain. Commonly used in the production of Yoghurt and cheese.
 
Sour milk, most likely Lactobacillus bacteria, the most common bacteria in grain. Commonly used in the production of Yoghurt and cheese.
Thanks mate. At least I know where I went wrong, lesson learnt.
 
Sour milk, most likely Lactobacillus bacteria, the most common bacteria in grain
Yep, totally agree. In fact, if you leave your spent grains hanging around for a few days after sparging then I'll almost guarantee that you'll get exactly the same smell again. If you're a bread maker as well as brewer, then you're half-way to creating a sourdough starter! I've also read that, if you leave your spent grains to sour like this, and drain off some of the liquid, then it can be added to a dry stout wort to create the original "Guinness" type twang. You apparently need to boil it first though, to kill off the bacteria whilst retaining the "souring" flavour, which makes sense. I must say that I haven't tried this myself! I might, though........
 
Yep, totally agree. In fact, if you leave your spent grains hanging around for a few days after sparging then I'll almost guarantee that you'll get exactly the same smell again. If you're a bread maker as well as brewer, then you're half-way to creating a sourdough starter! I've also read that, if you leave your spent grains to sour like this, and drain off some of the liquid, then it can be added to a dry stout wort to create the original "Guinness" type twang. You apparently need to boil it first though, to kill off the bacteria whilst retaining the "souring" flavour, which makes sense. I must say that I haven't tried this myself! I might, though........

You're putting me off Guinness........haha
 
You're putting me off Guinness........haha
Well, it doesn't sound too appealing, I'll admit! sick... From what I recall, though, it's only a small proportion that's added, and I guess that combines with the sort of burned coffee flavour from the roasted barley. And, after all, some continental beers are built like this from first fermentation - check out White Labs WLP655 Belgian Sour. This contains a strain of brewer's yeast, but also Brettanomyces "wild yeast" plus Lactobacillus and Pediococcus bacteria to give a deliberately sour flavour. Not my cup of beer, I guess, but I'm seriously considering buying some of this to make a different-tasting sourdough loaf. But maybe someone will like your new beer style of London Sour?? :D
 
Mash temperatures are incidentally exactly the same as pasteurisation temperatures. So leaving unboiled wort out in room temperatures for 3 days is just the same as doing it with a bottle of milk. Not a good idea...
 
Ive just had that funky slightly cheesy smell with a batch. I have looked into it and found out what I think has done this. I did a overnight mash but unfortunately I was asked to work longer in the morning that expected and the mash got left approx 16 hours in which time it lost temp to about 40c approx. When I went in the garage to restart the boil there was a strong funky cheesy smell so I sparged as normal and boiled the wort adding the hops etc as normal. the funky smell subsided a little but was still there so I decided to dry hop the beer to try and rescue the batch and see if it could hide the smell. " weeks after fermentation I kegged it and dry hopped in the corny for 12 days. The beer does have a slight funky smell when you bring it to your mouth but the beer actually tastes nice like a IPA with a slight sour taste. So dont throw it as long as you get over the slight funky smell the beer will taste ok or mine has. I understand it happened because of the Lactobacillus being brought into play with the mash temp dropping below normal temps which as has been said is used in cheese and yoghurt making hence the cheesy and sour taste. Its no worse than the sulphur smell that people get with some lagers but they get over that if the beer tastes good.
Maybe i've created a frankenstein beer?
 
Due to being called out I then left the wort to cool down for a couple of days before resuming. Upon lifting the lid I detected a very clear funky odour, not too dissimilar to soured milk. I boiled the wort for 60 mins cooled and pitched the yeast.

You need to be really careful about how long you leave unfermented wort as there is low but genuine risk of botulism forming if left for any longer than a few days. See the link below for further info.

http://beerandwinejournal.com/botulism/

I know you said it was only a couple of days which should be totally fine but it's worth being aware of the risks of going beyond that.
 
So what is the difference between this and making a berlinner weisse? Did they not used to sour the wort with grain?
I like the idea of making a sour dough starter but how would you go about it?

Control. Getting the bacteria you want to work whilst inhibiting the ones you don't.

Lactobacillus sours cleanly at a stable temperature and when oxygen is limited. Other bacteria favour oxygen and create acids that have off flavours.

Acetobacter - Vinegar (Acetic Acid).
Clostridium - Sick (Butyric Acid).
Streptococcus - Cheese (Isovaleric Acid).
 
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I like the idea of making a sour dough starter but how would you go about it?
At its simplest, it involves leaving a mix of flour and water at room temperature, so that wild yeasts and bacteria on the flour will multiply. To keep it going (at room temperature) more flour needs to be "fed" to the starter a couple of times a day. Basically, those yeast and bacteria best suited to the particular flour and environmental conditions will thrive and displace those less well adapted. I'm no expert on this - but my son-in-law in Australia pretty much is, he & my daughter have their own "family strain" of starter that they've had going for a good while now. So, it's not like a beer "starter", which you'd probably use just the once. Only a proportion of the bread starter is used in baking, and the rest keeps the strain going.
Incidentally, the WLP655 I mentioned above isn't a shortcut to making a sourdough starter, as the yeast & bacteria wouldn't be the ones that would dominate when fermenting flour. I just thought that using this beer blend for bread might make an interesting difference in flavour & I might try it sometime.
If you want to read more, this site has a great sourdough starter primer:
https://www.sourdoughhome.com/index.php
 
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