Cultivated Yeast Problem--I need some help

[kkoltunf]

Friends,

I cultivated some Wyeast 1056 from a previous brew and used it for my current black IPA. I refrigerated the cultivated Wyeast about a month ago, and then for the black IPA warmed it up to room temp and created a starter. I pitched the yeast and fermentation began nicely in about 20 hours. But then it stopped a day later, and when I took the final gravity measure, it came in at 1.033 (OG was 1.053). What happened? This is the first time I have used cultivated yeast for a brew, so I'm worried that I did not do it right, or did not add enough yeast. The fermentation temp was around 63 degrees, and I did not calculate how much yeast to add (in part because I am really unsure how much yeast I have in each of my bottles). When I tasted the beer (as I transferred to secondary fermenter), the beer tasted fine.

I would appreciate any suggestions about what I can do to prevent this from happening again.

Many thanks, Ken

 

[mkyl428]

How are you measuring FG? If you are using a refractometer the alcohol present is probably throwing off your reading, EDIT: I just re-read your post, one day is very soon, is that how long you waited to test FG? Just because you can't see it working doesn't mean it's done leave it alone for at least a week or 2 before testing for FG.

 

[kkoltunf]

I used a refractometer to measure the FG. How did the alcohol throw off the reading? How should I use the refractometer to measure the FG accurately?

I did not measure the FG after one day; I waited a bit over a week before transferring it to the secondary fermenter and taking a FG reading. My point was only that after a day there was no more bubbling/gurgling of fermentation.

thanks, Ken

 

[LLBeanJ]

Refractometers are not accurate once alcohol is present. There are some online calculators and spreadsheets to make the necessary adjustments, but their accuracy is hotly debated. At any rate, if you have a hydrometer, I'd suggest you use it for FG and then decide if you actually have an FG problem with the brew in question (I'm betting you don't).

 

[mkyl428]

+1 to what LLBeanJ said

 

[helibrewer]

What was your FG refractometer reading, in Brix?

Use this site, the polynomials are pretty darn accurate. Starting and ending inputs are in Brix, do not use the SG scale of your refractometer (if it has one).
refractometer calculator

 

[kkoltunf]

Friends,

Great advice!! Having now learned that the refractometer is not accurate when alcohol is present, I went to the website with the calculator suggested by hellbrewer and the numbers look good: comes out at 4.8% alcohol which seems about right. So all is well. Many, many thanks for the help.

Ken