I see a whole bunch of online pitch rate calculators such as this one by Brewer's Friend, but I'm struggling to find the actual formula(e) used under the hood by them. Does anybody know of any generally-accepted pitch rate formulas out there? Ideally I'd like to know what Brewer's Friend is using but I'll take anything thats in the ballpark.
Most of the time, adding yeast at bottling time is not necessary since enough healthy yeast remain in suspension to consume the priming sugar. But in cases where the existing yeast might not be sufficient, I was looking for a reference to for the quantity of healthy yeast to pitch at bottling time. From this site, I have found references to 10%, 25%, and 33% of the original pitch rate, but there were no external references to those recommendations. The …
From what I read in most publications, ester production tends to increase at lower pitching rates. It's not a linear relationship by any stretch of the imagination; in fact there seems to be some sort of a U-curve at work here but, generally and broadly speaking, a lower pitching rate (even to the point of judicious underpitching) tends to produce higher levels of fruity esters, while overpitching tends to lead to a "cleaner" flavour profile with lower levels of fruity …
I'm trying to improve my understanding of pitching rates, and I'm struggling with some apparent inconsistencies. An often used starting rule is to pitch about 750,000 cells per milliliter per degree Plato for ales, and twice that much for lagers. So for an example batch of 5 gallons (20 liters) of wort at 10°P (OG = 1.040) you'd need about 150 billion cells for an ale and about 300 billion for a lager, in order to get a consistent and …
I washed some yeast ( US 05 ) from my last brew; and I now have 3 jars of yeast which separated out nicely overnight. They're around 2/3 yeast, 1/3 liquid at the moment, with no trub as far as I can see. I want to use one of these next week and I'd like to know how much to use, so I went on to Mr Malty's calculator ( re-pitching from slurry tab ). There's a slider for "yeast …
I'm interested in buying a microscope that I can use to observe yeast cells. Ideally, I'd like to use this to count cells in region and do calculations to get estimated populations (though I don't know how to do that yet). Also, if there is anything to be learned by looking at the interior of the yeast cell (not sure if there is from a home brew standpoint), then I'll need one powerful and clear enough for that. Lastly, I …
I've started a brew with an OG of 1.065 in a 23L batch. I pitched a rehydrated 11g pack of US-05 and after 5 days I took a FG reading when I observed no bubbles after some time; it came out at 1.028 - quite a bit higher than expected (target FG is 1.012). So, I upped the temperature of my fermenter having realised I only set it at 17degC (oops, I meant to do 19degC but I'm hoping it …
I have an imperial stout that seems to have slowed fermentation ~ 1.040. I made a 2L starter w/ Super San Diego yeast on stir plate and pitched it at high krausen.. no decanting. Based on Mr. Malty's Yeast calculator, I needed 2.75L of starter for an OG 1.10. So I took slurry from my cider (Champagne yeast), created two 2L starters and cold crashing now and will decant this time and pitch both. The amount of yeast at bottom …
I'm brewing on Sunday (today is Friday), and I neglected to get my yeast (WY1056) until just this afternoon. I could make a starter, but I don't know if it would reach "high krausen" in time for pitching Sunday night. And I certainly wouldn't be able to cold crash it, as I normally do. Or, I could just pitch the smack pack, which has a manufacture date of 13-Feb-2012. Beer Smith tells me that the yeast is 84% viable, yielding …