First time AG question

[Potamus]

This was my first all-grain brew, and it came out differently than the extract/partial mash recipes I've done before. I brewed Aug. 31 and when I opened the fermentor this morning, I saw a layer of particles floating on top (not positive if it's grain debris or something else). The vessel had a pretty sour smell, and I didn't see the ring I usually get from the krausen. But when I took a gravity reading, it was where it should have been, and the sample smelled and tasted fine. I went ahead and bottled it, figuring time will tell. I'm just wondering if the layer on top, sour odor and lack of krausen ring is typical with an AG batch or if something is wrong.

BTW, it was a basic stout recipe:
5 Lb. Maris Otter
2 Lb. Flaked barley
1 Lb. Black roast barley
2 oz. Kent goldings
1 tab whirfloc
Safale S-04

 

[half_whit]

I had the same thing happen to me and it took me 3 brews to figure out why. I tried to save money on my brews by switching to dry yeast. According to the packaging, all you have to do is tear and sprinkle! Trouble is, in doing this half of your yeast dies right away. You really should make a starter or at the VERY least rehydrate the yeast. The sour smell (and resulting flavor) is caused by the yeast getting stressed because it has to use more energy on reproducing (to make up for the dead cells) instead of focusing on the sugars. What you're seeing on top is yeast cells that never got past the initial sprinkling. Since fermentation didn't run as vigorously as normal, it never had a chance to produce that thick krausen we're used to.

 

[half_whit]

Also, now that you're doing AG you'll need to pay more attention to your water. If you're using tap, contact the local water company to get a copy of the water report. If you're like me and have no idea what all the numbers mean, post it on the forum and see what people say! It's possible that you might need to adjust pH or give the yeast more nutrients from time to time.

 

[chickypad]

Those look like normal yeast rafts to me. The main difference between AG and extract is how you produce the wort, but shouldn't make a huge difference in your fermentation process. Every fermentation is different, but more likely be affected by things like pitch rate, yeast health, oxygenation, SG, etc. The sourness could be a concern, mainly infection, although I see no signs just based on the picture. If it tasted good and you hit your target FG I think you're very likely fine.

 

[Setesh]

The picture isn't clear enough for me to make out much detail, but it looks fine to me. It also looks like you have a krausen ring. How did you pitch the 04? Did you rehydrate? Rehydrating the dry yeast makes a huge impact on viability and pitching rate. You shouldn't have to make a starter with dry yeast, just pitch the correct amount of rehydrated cells.

I have found that 04 has a bit of a sour smell to it, but it doesn't come through in the taste. I think you are probably fine on that point.

I always put bottles in tubs with lids in case of explosions as a safety measure, just in case. Cold conditioning also slows infection down greatly. Again though, it looks OK to me. I just do this since having an infection problem and HUGE mess after a cracked stir bar infected multiple batches of my beer.

 

[Potamus]

Thanks everyone. I do always rehydrate my dry yeast, since I've heard it results in more viable yeast cells. Also, I always use distilled water when I brew. I'll let them sit a few weeks to carb and see how they come out.

 

[Travestian]

If you are using distilled water you absolutely have to add minerals to your water to treat your yeast like they deserve.

 

[Setesh]

If you are using distilled water you absolutely have to add minerals to your water to treat your yeast like they deserve.

+1 to this. The mash needs minerals too. Distilled is fine for extract beers because the minerals are in the extract, but for all grain you need to add minerals to the liquor before adding it to the mash. Here is a great tool to help you accomplish this:

https://sites.google.com/site/brunwater/

I'm still struggling with this with my tap water. They change the source on me so often I never know what I'm getting. I think I'm going to have to do what you do and go distilled. Then I will adjust it to the current grist. I might just set up an RO filter and call it done.

 

[Potamus]

Ahh...I didn't know that. Thanks for the link!