Midly sour stout

[jzamora3]

Just drank my first bottle of Midwest's oatmeal stout recipe. I followed the recipe pretty close but made a few minor adjustments. My first few bottles have a slight sour smell and a sour taste toward the end of the drink. Any ideas what caused this? I used regular Albuquerque tap water with no treatments.

Steeping grains 30' @ 155
Rolled oats 10 oz
Chocolate malt 4oz
Roasted barley 4oz

3lb dark lme @ 60'
3lb dark lme @ 15'
1oz fuggle hops @ '60

10g of rehydrated safale us 04

Fermented at 63 degrees for first 7 days then rose to 71 for the next two weeks.

Bottled at 2.2 carbonation level with 5oz of maltodextrin added to priming sugar boil.

 

[jzamora3]

Oh and bottles have been carbonating/conditioning now for about 4 weeks

 

[petersusaf]

Did you ferment at 63 degrees air temperature or actual liquid temperature? Also did you get an explosive fermentation? I'm wondering if the temps may have gotten too high causing the sour taste.

One of the first stouts I brewed, I had a similar problem. I fermented it too high and the yeast released a lot of esters. I left them in the bottles for around 4 months and it actually mellowed out pretty nicely. Now it's a pretty enjoyable brew.

Hopefully that helps some.

 

[jzamora3]

It was at 63 air temp. With my current set up, that's as low as I could possibly get it. Looking at the fermetis website, it shows an acceptable temp range of 53.66-77f. So I figured, add an extra 4-6 degrees to the wort temp and I'll still be within the acceptable range. It was pretty explosive fermentations, really quick from what I remember. I beleive the krausen fell within a couple days after it reached high krausen. But okay, I'll let it sit for a bit long in the bottles and hopefully the extra time will mellow out those flavors.