Slower fermentation

[WortIfied]

This I a five gallon batch I brewed up on Wednesday 5/23. The OG came out to be 1.098 on my extract recipe for a black rye IIPA.

Fermentation began with visual signs within 12 hours, this is my 5th batch and the first one so far that didn't just take right off and rape the air lock. It's been a slow and steady fermentation, 1-2 inch of krausen, and 1 bubble ever 1-2 seconds. It has been consistently like this since fermentation has began. Now, I do realize I'm not supposed to judge anything by the airlock, I'm using a Carboy btw so it's easy to read the krausen height. I am curious however because I did a few things new this batch.

I rehydrated 2 packets of us-05 at 90f for this, pitched at about 75f, stuck Carboy in swamp cooler and got down to 64f where it has been steadily. My first time using rye specialty grains, and my first time using fermcap. Unused about 5 drops in the boil because of the boilover from all the hops. Another first time for me is forgetting to aerate with my oxygen and stone... I'm leaning towards this being the culprite for a not-so-vigorous fermentation this time around.

Me still being quite the beginner, do I have anything to be concerned about with a slower, steady fermentation where I noobily forgot to inject oxygen?

 

[Andrew5329]

As long as your sanitation was good you don't have anything to worry about persay, the primary risk in slow/delayed fermentation is that competing bacteria might have the chance to do some mischief before the yeast consume all the available sugars. Since I'm assuming your sanitation was up to snuff your yeast still have a fast enough head start.

You answered yourself why your yeast are slow, aerobic respiration (with oxygen) creates 36 ATP(the "batteries" cells use to do stuff) per glucose molecule, while Fermentation only produces only 2 ATP per glucose molecule, hence why you didnt get the "airlock rape" you described.

Just add an extra few days onto whatever your bottling schedule was going to be and no-one will know the difference.

 

[WortIfied]

Yeah, I figured! Oh well, mistakes happen, I had my oxygen tank sitting right next to my swamp cooler, guess I just kinda rushed things. I do take my sanitation seriously, I keep a sanitizer spray bottle on hand and keep things wet. I kept my lid over the kettle while the immersion chiller did its thing, and emptied te Carboy of sani water solution just before funneling.

Usually after aerating the crap out of the wort the headspace in the Carboy would be just about bubbled over, not sure why I forgot this step this time around hah. I have always used dry yeast, just sprinkled into the wort and would usually see results in 4 hours.

It's unreal how much oxygen injection can make a difference. I planned on a 2 week primary before taking the first hydro reading anyways, I'll see where I stand then.

 

[Andrew5329]

Yea, it's always the simple mistakes that happen lol, I was 1/3 the way through bottling a batch of Ginger Ale (7.5%ABV ) yesterday before I realized that I didnt add my priming sugar, thankfully I was using 1 Liter Grosch swing-tops or it would have been a nightmare to fix it with capped 12oz bottles.