rapid fermentation

First of all I'm still fairly new to beer brewing. I've always made cider. This wa s my third extract. I brewed a dry Irish stout and made a starter with Safale US04. Instead of setting it in my basement(60 degrees at the time) I left upstairs (67 degrees) i have never seen anything ferment so rapidly. It sounded like a machine gun. I was surpised how much heat was generated by the fermentation. It was done in 3 1/2 days (OG was 1.040) Is that normal? Are there any side effects to flavor by a rapid fermentation? Thanks

Sounds about right to me. Not sure what you were expecting, but the dry yeast (compared to the liquid) has more cells.

If you're not in a hurry, you may want to let it sit for a week more or so and let the yeast clean up and floc out.

Thanks I was going to let it set for a couple of weeks and rack it off to the secondary. I was just kind of shocked because my cider tends to go for weeks

I agree with weetod, a 3 or 4 day fermentation for a 1.040 gravity beer is typical when using dry yeast. I will often pitch 2 or 3 packages of dry yeast to get a quick and effective ferment going. When the fermentation is complete, leave the beer to clear and the yeast to recover some of the esters and phenols that it produced initially during the rapid fermentation phase. Even though the gravity reads complete after 4 days I will let the beer sit for 7 to 10 days on the yeast before racking. Just the way I do it.
mark
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