Help! Vinegary taste AGAIN

Hey folks, I'm new to this. Only on my second Cooper's homebrew batch. First was a lager came out tasting like it had old apple juice stilled in it.

Did the stout this time. Followed directions exactly. It's been fermenting now for about 2-3 weeks. The s/g seems to have levelled out at about 1.005. which according to my initial gravity somehow gives me a light beer at like 3.6/3.7%

But although it tells me to bottle when this happens I tasted it and it again has a vinegary/old apple aftertaste to it. Very bitter. If I leave it longer will anything change? Or is this kit total garbage or something??

So frustrated!

 

Perhaps the attached is helpful?

 

I don't know what to do for the idea of infection. I cleaned all the equipment with the proper chems from a DIY brew store, haven't opened it since I took out the kreseun collar a few days in. Not sure how to actually tell is there IS an infection. Is there a test or something?

 

Our eyes, nose and taste are normally used to detect and identify an infection.

By "First was a lager came out tasting like it had old apple juice stilled in it." do you mean vinegar? If so, please refer to the pdf I attached.

Unfortunately, once vinegar it will always be vinegar (in other words it will not go away with aging).

 

What was the OG?

 

1035 or so

 

1035 is very low for an OG. However, I calculate 3.9% ABV based on the numbers provided.

Did you top off with water in the primary fermenter?

 

I'm also not sure how great the plastic hydrometer is that comes with the kit.

Yep mixed in the dry ingredients along with the canned sludge they send you in about 2L of hot water. Then added up to the 23L mark as told maintaining temp at around 21 Deg celcius

 

Perhaps the 2 attachments are helpful?

 

Most hydrometers are calibrated at 60F or 62F. Hydrometer should state somewhere the calibration value.

What was the size of the malt extract can used in the brew?

 

Hang in there... we'll get this fixed once we understand what is going wrong. OK?

 

Umm... did boil everything to sanitize things?

 

1.7kg can I believe. I've looked it up and I can see vinegary flavour suggests infection but just can't see how it's happened twice in a row and I've done as good as I can imagine to properly clean and sanitize and I never open the tub when not necessary.

 

I had to look up the krausen collor you said you removed. If it indeed moves up and down during fermentation there has to be a little space to let it do that easily. Could you have fruit flies or maybe a wild yeast getting into it? From what I understand that can give you the vinegar flavor.
Just a thought.

 

Bought all the cleaning chemicals at a beer store, only used soft cloth to wash and wipe. Didn't open it anytime that wasn't necessary.


The collar doesn't move during fermentation, it's held down with plastic clips. A few days in the froth subsides and the level of liquid is below the collar so it isn't needed, and you lift it out because the sides are covered in the gross dry froth scum. Then you put the lid back on (but no longer clipped down, just gravity).

 

how old was that can of LME

 

What's LME? I'm gonna guess. Light...malt...extract? Lol

The stout malt I used was like 3 months old. Still had like a year on expiration date

 

Liquid malt extract. Ok just thought id ask because ive seen those coopers kits on the shelves of homebrew stores and some look like they have just been collecting dust for the past 5 years.

 

Is no one concerned that the wort was not heated to pasteurization temperatures, let alone boiled to sanitize? To me, that is a concern.

Which chemicals, specifically, did you use to clean and sanitize?

This Krausen Kollar, seems to be an extraneous piece of equipment that is really not needed in a properly sized fermentation vessel: The ring of "gross dry froth scum" is just a normal part of fermentation and does not cause any issues in the fermenter.

In order for acetic acid to form, you need two things: a source of acetobacter contamination (fruit flies or other intruder) and oxygen. A properly sealed fermentation vessel should prohibit both.

 

I'm going to note here also, what you might be tasting is "green" apple flavor; everyone perceives some flavors differently than others. If it IS vinegar, then yes you are looking at an acetobacter infection, commonly caused by fruit flies, and won't go away; if it just tastes like green apples, it needs more time, and maybe some help; this is commonly known as acetaldehyde.

I'm also going to ask about the yeast; did you use the yeast that came with the kit? What was the expiration date? Was there visible fermentation within 36 hours of pitching? Some kits are notorious for including yeast that may be out of date.

If it IS green apples you're tasting, you might be able to help it dissipate by taking your fermentation vessel into a warmer area of your home, to help it finish out. What was your fermentation temperature?

 

So basically instead of shipping a larger fermentation vessel, they have you use another piece of plastic that is just another thing that needs to be sanitized? Seems like a weird design choice.

 

The krausen ring type fermenters appear to be pretty common in the U. K. and work very well. Actually it's a pretty good system.

The Cooper's and other canned kits generally are "no boil". These too are a lot more popular in the UK and Australia. People get good results with them and few infections.

I too think what you are getting is the green apple flavor of acetaldahyde.

All the Best,
D. White

 

Perhaps it is the green apple taste. I'm new so don't have a superb sense of all this stuff. I did use the yeast supplied with the pack, I did not look at the expiration but it comes sealed in the cap of the can of malt which I did check and was fine so I assume the yeast was too.

Absolutely it worked, within the first day I already saw fermentation beginning and that foam began to develop.

I have I think perhaps figured it out though. But not sure. That kit comes with that clear tub as shown above. However nowhere in the instructions does it say where to let it sit, apart from keeping the temperature between 21-28 degrees Celsius which I did. It usually was reading about 22.

But I left it in my TV room downstairs, where there is a window, and light. And I have been reading that it should be kept out of the light?? Is this true? Because this would be a similar thing I did which the first batch that came out vinegary as well. Should it be kept in the dark?

The kit mentioned nothing about this.

 

Wondering about this too.

 

Something to think about for this beer. To get vinegar you need acetobacter to infect the beer and once it starts it continues to get more vinegary until it completes its activity. At the end you have malt vinegar.

If you instead have acetaldehyde you get a green apple flavor and with time the yeast usually clean this up so the flavor improves. Letting the beer warm up in the fermenter usually helps. In a couple more weeks you will know which you have.