Shaking/aerating wort after pitching yeast

Hi everyone!

I'm basically done conditioning my second ever batch of homebrew. By the measure of everyone who tasted it (including other homebrewers), the first batch, a brown ale, was a success. However to me, it tasted really sweet and almost had like a savory-ish taste. I tested a bottle of my second batch, a chocolate milk stout, and I got the same flavor as well. I never noticed an infection during fermentation, and I don't think the taste is attributable to that.

On brew day for both batches, I've felt compelled to shake the carboy after pitching the yeast. The first time was because I'd forgotten to aerate the wort, and the second time was because there was so much Star-San foam that the yeast was resting on top of it, rather than the wort. In both cases, kraeusen and airlock bubbles came and went within the first three or four days. I think it was after brewing the second batch when I saw some sort of warning against aerating the worth after pitching the yeast. I'm thinking that maybe in both cases, not enough yeast was in contact with the wort, so a full fermentation was prevented. Could that be the case? Thanks!

(There's also the possibility that everything went as it's supposed to go, and I'm just being too over critical.)

 

I aerated once after pitching yeast and I didn't notice any taste issues. I used to shake the carboys or buckets but got tired of doing that and went to pure oxygen. Much easier and no chance of dropping the carboy during the shaking process.
I also had one brew that I felt was overly sweet. I attributed that to high mash temp. All other batches have been mashed at 154 or less.

 

Aerating/Oxygenating beer is generally bad after fermentation is under way. But shaking it up right after your pitch? I think everyone will agree that was fine. If the volume of O2 in the wort was low before the pitch, you probably helped a bit.

Infection? Savory-ish? Might be a contamination. Might be mash temps. Might be fermentation temps for a particular yeast. You will find most here will want to know your recipe and process before they speak to that. Maybe a few will pick off your problem from what you have written. Bottom line will be... If people are happy drinking the beer, let them drink it fast! While you will never know for sure whether you had a contamination issue or not, the upside is you will never know for sure whether you had a contamination issue

 

The recommended time to oxygenate your wort if after pitching your yeast (per Papazian). This how/when I routinely oxygenate my wort. I use O2 from an E-tank w/ a regulator & 500 micron stone.

 

Need some more details...recipe, yeast used, fermentation temperature, process details. Any small problem with your methods or ingedients can cause an off flavor. But most are correctable in future batches. Don't lose hope!

 

If you saw kraeusen rise and fall in 3-4 days, that is about normal, so your fermentation probably went fine. This should be verified with gravity readings if you have any doubt.

Not sure what to say about a "savory" flavor but this descriptor does not scream "infection" to me at all. Maybe you under-hopped? Too much crystal? Too much lactose (in the case of the milk stout)?

There are many who believe that wort oxygenation isn't even necessary at the homebrew level assuming you have an adequate yeast pitch (cell count and health). In light of that, I doubt your oxygenation practices have anything to do with anything here.

 

Both batches were Northern Brewer kits.

First batch - Caribou Slobber Brown Ale
.25 pounds of Breiss Caramel 80L
.25 pounds Fawcett Pale Chocolate
.125 pounds Black Malt
6 pounds Amber Malt Syrup
1 pound Amber Dry Malt Extract
1 ounce US Golding hops
1 ounce Liberty hops
1 ounce Williamette
Danstar Windsor Ale Yeast

Second Batch - Chocolate Milk Stout
.25 pounds English Extra Dark Crystal
.75 pounds Fawcett Pale Chocolate Malt
6 pounds Dark Malt Syrup
1 pound lactose
1 ounce Cluster hops* (60 minutes)
.5 ounce Cluster hops* (30 minutes)
4 ounces cacoa nibs

*I didn't realize that the kit included two 1-ounce packets of hops, so after trying to figure out what to do, I added all 1.5 ounces of Cluster hops at the beginning of the boil.

As far as temp is concerned, I'd say it was in the 70-75 degree range both times. I'm drinking a second bottle of the milk stout now, and it doesn't have that savory taste I described, so maybe it's just part of the flavor profile of the brown ale (the milk stout was also needed more conditioning when I tasted it the first time). Thanks for the advice and putting my mind at ease. It may not be as big of a problem as I thought it was.

 

I used to shake the bucket around.Now I use a $3 paint stirrer from home depot and its way easier.Im one of those people that are on the fence if aeration even makes a difference.Ive done the same recipe with and without aeration and got the same ferment time and tasted the same.Ill keep doing it because its easy but wouldn't sweat it if I didnt

 

I use a whisk to aerate. Simple and cheap, and I don't have to worry about running low on brew day.

 

The "sweet" flavour is likely due to the use of malt extract, in my opinion, and possibly a high finishing gravity that is often characteristic of such recipes. I don't think it has anything to do with the timing of your aeration.

You mentioned your yeast was "sitting on top" of the Star San foam - that suggests to me that you were using dry yeast that you sprinkled in dry. It's a minor thing, but I would encourage you to consider rehydrating your yeast next time, per the manufacturer's instructions (just Google the "data sheet" for whatever strain of dry yeast you're using and look for the PDF links). Finally, in my opinion, you're fermenting too warm. This can produce different esters and higher alcohols, which you might be perceiving as some varying degree of "sweetness." Again, consult the data sheet for the yeast, and try to keep the beer's temperature in the low end of the prescribed range.

 

Not sure about savory, but you have two beers that are supposed to be very malty, flavorful beers. The milk stout in particular contains lactose that is unfermentable to give it sweetness by design. I would suggest repeating your process with a beer with a simple highly fermentable grain bill (no lactose or crystal malts) and a high attenuating yeast, such as US-05 or a saison. Then if you get any off flavors, you will know that it is from your process rather than the recipe.

 

I use pure 02, 1 minute. Seems to works out just fine for all of my brews.

But my last wheat beer, I forgot to aerate at all. didn't use O2 didn't shake, didn't whisk. Just cooled, drained, and pitched.

That one came out great too. I think moving the IC around during cooling introduced enough O2 so that it was fine.

I think on homebrew scale it's not the most important variable. YMMV.

 

My very first brew was that Caribou Slobber and I think I know exactly what you are talking about with the flavor. A lot of my friends had been brewing for some time before I started so when we had our first tasting (about 6-7 weeks post yeast pitch) the results were far from positive. However, I gave it some time and a chance as that recipe has gotten quite good reviews. It turns out it needed a lot more time (at least for me) before it resembled the Brown Ale I was expecting. Bottle condition it another 2 to 3 weeks, and I bet you'll like it a bit more.