I’m making an Irish Red Ale, OG ~1.054, and pitched some Wyeast 1084 leftover from a previous IPA. I have to admit that this is my second repitch of this yeast, but after the first batch I took steps to reinvigorate the yeast (i.e. grew it for a day on a stir plate with nutrient) so I doubt it was too tired on this, the third batch.
I initially pitched around a cup of thick slurry, but when my fermentation didn’t take off within the usual 12-18 hours, I suspended the remaining ~3/4 cup in a bit of sterile wort, stirred for ~3 hours to aerate it and wake it up a bit, and pitched.
By 36 hours I still had no bubbles, so I boosted the temperature in my sink from 62 to 66 (i.e. 16C to 19C). The yeast seem finally to have woken up.
What I’m wondering is, what will be the consequences, if any, of having started the fermentation off too cold, as appears to be the case? (Add to that the fact that I now probably overpitched…)
You know ive always had the same question as you. I use wyeast 1084 which recommends 62-74F so i dont see whats wrong with keeping it at 62F. I have had some really energetic fermentation at +68F anything lower than that it is really sluggish. By sluggish i mean 18 hours util high krausen, perhaps during pitching make sure the wort is above 66F. Honestly i don’t think you over pitched, i make 2 liter starters 1.04 OG starters and when i pitch the thing it always explodes into life. My conclusion and opinion is that you pitched enough, but the temp was perhaps too low for a very active fermentation. During the beginning of fermentation the yeast is reproducing and if the temp is too low it makes the process harder for the yeast. That’s why when you ferment at higher temperature everything seems to be more active. This is merely my own opinion because i only use wyeast 1084 and Safale s04 both of these yeast are at their 6-8 generation of repitching. Ive made atleast 10 beers using these yeast so i don’t think this is because its a repitched yeast.
You might consider another thing that happened to me just yesterday.
When I placed the fermenter in the freezer, I accidentally moved the temperature probe and it got between two bags of grain. So while the probe temperature was 62F, the rest of the freezer was at 55F and I did not see any signs of activity for 9 hours. Needless to say I was panicking; my fermentations usually start in less than 4 hrs (I use yeast nutrients, cool the wort to the fermenting temperature, run a starter at the fermentation temperature and oxygenate my wort with pure oxygen)
Just before going to bed I moved the temp probe to its standard position and the temperature went up to 62F through the night.
This morning the beer is fermenting as happy as can be, so I don’t think that cold temperatures (down to ~55F) at the beginning of the fermentation affect it significantly, as long as you raise the temperature to a healthy range for the yeast.
I typically ferment my ales at 62F and get standard take offs and landings as far as activity is concerned. I would suggest buying some fresh yeast, make starter the next time, and see if you get a better result at the same temperature.
I don’t really think it was a yeast health thing, though I can’t be sure. The temperature may just have dropped a bid lower than I hoped. My thermometer (digital) can be switched between Fahrenheit and Celsius, I’m a metric guy but for homebrewing I do a lot of Imperial units - and switching back and forth - especially since 99% of people on the forums are Americans who are more used to Gallons and Yards and Gills and Furlongs, etc.
Anyoo, my thermometer read 16-17C which I calculated as ~62F, but when I actually flicked the little switch it actually read 59-60 F.
It finally picked up and is chugging nicely. I was trying to keep it low because I’m doing it in a carboy with not quite as much headspace as I would like. Just needed to tweak it a bit.
