IPA Turning Brown in Fermenter—Oxygenation? Contamination?

[Spacelover02]

I'm relatively new to homebrewing (been home-brewing for over a year now but usually with a group), and just did my first all-grain solo brew a week and a half ago. The beer is meant to be a 3 gallon rosemary and coriander IPA (mainly 2 row grain). It's been in the carboy for a week and a half now (still bubbling on occasion). A day ago, unfortunately, I discovered that the relatively light (though still darker than I expected) amber color had turned quite dark. I'm including two photos for reference, the first taken day one, the second, today, a week and a half into fermentation. The color seemed to change quite quickly, over a day. Unfortunately there's a lot of airspace because this is a smaller brew, but I've never had a problem with this before. I wondered in the beginning if the bung had too loose a fit—there was still a seal, but it seemed barely a seal to me. I did have trouble in the beginning cooling it (no wort chiller unfortunately, so I used snow from the recent snowstorm, but it took an hour and a half). So I'm half-wondering about bacterial contamination as well.

I've kind of given up on it, assuming the beer's been oxygenated and the flavor's ruined. Does that seem like the likeliest explanation? Is it possibly bacterials? Any hope?

 

[Jag75]

Its hard to really tell how dark it is in the fv. Plus lighting in the house . I do think you need a smaller fv so there's not so much headspace.

Before you dump you should try it . Pull out a sample to check the gravity . If it really looks brownish in your tester then you can assume its oxidized.

Try and get a chiller or make one . I know there's brewers who do no chill but I've always tried to get the wort down to pitch temp quickly because your wort is susceptible during this time , at least thats what I was taught.

 

[ATLBeer]

Looks like beer to me.

It just looks like your suspended material, which is lighter in color, has settled out more, leaving darker looking beer which has more clarity. Beer always looks darker in a vessel than in a glass.

Headspace is not an issue as way more CO2 was generated that that volume. Not having a perfect seal is OK as long as it is fermenting. and with that small of a mouth, any ingress is going to be minimal anyway.

An hour and a half to cool isn't great, but its unlikely to be an issue. Did you use snow outside or in the sink? With a 3 gallon batch you could have used a 5 lbs bag of ice in less than 30 minutes. Leave it in the pot with the lid and agitate a bit.

 

[Spacelover02]

Its hard to really tell how dark it is in the fv. Plus lighting in the house . I do think you need a smaller fv so there's not so much headspace.

Before you dump you should try it . Pull out a sample to check the gravity . If it really looks brownish in your tester then you can assume its oxidized.

Try and get a chiller or make one . I know there's brewers who do no chill but I've always tried to get the wort down to pitch temp quickly because your wort is susceptible during this time , at least thats what I was taught.

That's a good note on getting a smaller vessel, I'll look into that. I'll definitely try it out and check the gravity prior to doing anything drastic. And yeah, that's a good point, I'll make sure to grab a chiller as well—definitely don't want to cool for that long again.

 

[Spacelover02]

Looks like beer to me.

It just looks like your suspended material, which is lighter in color, has settled out more, leaving darker looking beer which has more clarity. Beer always looks darker in a vessel than in a glass.

Headspace is not an issue as way more CO2 was generated that that volume. Not having a perfect seal is OK as long as it is fermenting. and with that small of a mouth, any ingress is going to be minimal anyway.

An hour and a half to cool isn't great, but its unlikely to be an issue. Did you use snow outside or in the sink? With a 3 gallon batch you could have used a 5 lbs bag of ice in less than 30 minutes. Leave it in the pot with the lid and agitate a bit.

Ok that's good to know, especially on the small mouth, hadn't thought of that but excellent point. Yeah I used the snow outside, but I did keep the lid on, so though not ideal I was hopeful it didn't get contaminated. I think I might have accidentally insulated it due to the amount of snow I used around the pot...oh well. Next time it's be a sink with an ice bag as you noted, or I'll just get a wort chiller.

 

[ATLBeer]

Yea, if you just set it in a snow bank, it'll be slower, needs agitation. But still 1 1/2 hours with the lid on isn't going to cause any problems.

Try the sink ice bath, and save the chiller for when you step up to larger batch sizes.

 

[RM-MN]

Ok that's good to know, especially on the small mouth, hadn't thought of that but excellent point. Yeah I used the snow outside, but I did keep the lid on, so though not ideal I was hopeful it didn't get contaminated. I think I might have accidentally insulated it due to the amount of snow I used around the pot...oh well. Next time it's be a sink with an ice bag as you noted, or I'll just get a wort chiller.

By itself snow is a great insulator. Get a tub bigger than your pot, put some water in it, dump snow into the water. After 10 minutes, add more snow. After 25 minutes add more snow yet. It will chill much faster than just setting the pot into a snow bank.

 

[Spacelover02]

By itself snow is a great insulator. Get a tub bigger than your pot, put some water in it, dump snow into the water. After 10 minutes, add more snow. After 25 minutes add more snow yet. It will chill much faster than just setting the pot into a snow bank.

That's a great note—very appreciative of the no-cost cooling solution.

 

[bwible]

Looks normal to me. The first picture still has active yeast and suspended particles. Has that classic “kraft caramel” appearance. In the second picture the beer has dropped clear. Color always appears darker in bulk. This will look different in the carboy than it will in a glass.

For container sizes, I use a 5 gallon carboy as a primary fermenter and a 3 gallon carboy for a secondary. There is much debate today about the use of secondary fermenters and I’m not intending to go there. Just pointing out it’s available as an option. I also have a couple 3 gallon kegs but those are getting harder to find without spending $100.

 

[Spacelover02]

Looks normal to me. The first picture still has active yeast and suspended particles. Has that classic “kraft caramel” appearance. In the second picture the beer has dropped clear. Color always appears darker in bulk. This will look different in the carboy than it will in a glass.

For container sizes, I use a 5 gallon carboy as a primary fermenter and a 3 gallon carboy for a secondary. There is much debate today about the use of secondary fermenters and I’m not intending to go there. Just pointing out it’s available as an option. I also have a couple 3 gallon kegs but those are getting harder to find without spending $100.

Thanks for this, takes some of the anxiety off. I'll take a look at the color in a glass in a few days and get a sense, and taste it of course. And yeah, secondary fermentation debate aside, I think it might be good for me to invest in a 3 gallon carboy all the same, since I tend towards smaller batches.