Yeast rates

[Brewnaldo]

Does anyone know or have a graph of attenuation rates for various yeasts?

It occurred to me when I tested my milk stout yesterday and immediately assumed there was a problem that I know nothing about where it SHOULD be at this point. Obviously with differences in yeasts, SG, expected FG etc full attenuation can take different times. Is there a rough guide of what the curve looks like?

 

[Zephyr259]

What yeasts are you using? Wyeast list attenuation spreads on their website, Whitelabs do too but a bit broader ranges it seems. Not used dry yeasts in a while but I recall they often just said high or low. Mash temp will also affect things, my experience is with the grainfather online recipe builder, you put in an average attenuation which it then adjusts based on mash temp. 67.5c seems to be where it doesn't make an adjustment and I tend to plug in the mid range number from Wyeast's ranges, tends to be pretty accurate especially on a re-brew where I have personal data to adjust the average attenuation figure. Hope that makes sense.

 

[Brewnaldo]

I think I get you but I am more looking for a time elapsed/attenuation type relationship.

The thing is, I dont want to be sitting wondering if things have slowed up or stopped when in reality they might be on track.

I do accept part of this is down to inexperience on my part....

 

[Zephyr259]

Ah right, sorry I misunderstood you before. To track fermentation you'd need something like a Tilt or iSpindle, the latter being a DIY tilt as far as I understand. They connect via Bluetooth to a phone and measure SG and temp constantly so you get a trend over time. Otherwise it's just a matter of brewing with a yeast a few times and getting to know what it usually does. I know Wyeast 1469 West Yorkshire fairly well by now, especially in my bitter where the airlock goes silent about day 4 and the gravity is stable by day 7.

 

[Ben034]

I don't you will be able to find the answer for this one. The rate at which an individual yeast works and therefore time taken to attenuate to a certain point will depend on a number of factors; initial OG, amount of yeast pitched, temperature at pitch of yeast, liquid or dry yeast, starter or no starter, fermentation temperature, size of batch, shape of fermenter etc etc. Take a sample and test a day apart and if the SG is still dropping all should be well. Alternatively, leave it at least 2 weeks and check then.