Sunday, January 6, 2008

Day 12 Progress.

Ok so it's been about a week since my last update and my fears from day 4 were confirmed. At about day 6 I noticed there was no activity in the air lock. I took a gravity reading and it was still at 1.020 (about 55% attenuation). So I decided to transfer to the secondary fermenter thinking this would help remove some C02 and re-suspend the yeast that had settled to the bottom and maybe get things started again. A day after transferring I still had no activity in the airlock and I was still reading 1.020. . . .It was fairly obvious I had a stuck fermentation. I wanted to be sure it was stuck so I waited until day 11 and once again the gravity reading was the same. So I went to the home brew shop to pick up some red star champagne yeast and made a 500ml starter with 2oz of light DME. After about 8 hours there was plenty of activity in the starter so I pitched it into the beer. Now about 12 hours after pitching on day 12 there is airlock activity every 35-45 seconds. I haven't taken a gravity reading yet. I'm going to wait a day or two to see how the airlock activity goes. White labs web site states that WPL004 should reach 65-75% attenuation so if I can get close to that I'll be happy.


Some notes about various things:

1.I think the reason for the fermentation being stuck was lack of aeration to wort prior to pitching. Thus causing reduced growth and reproduction of the yeast during the lag stage. I did attempt to aerate by using a hand held shower head on spray setting when I added water to the(concentrated)wort thinking this splashing action would aerate it enough. The problem was I aerated the wort when it was still hot. Essentially I added the cold water in an attempt to cool the wort. When the wort is hot gases are less soluble so the O2 that I attempted to add escaped during the long cooling time. In order to avoid this problem in the future I think a wort chiller will be my next purchase . I would also like to get an O2 injecting system eventually as well.

3. After doing research I realized that 2oz of DME may have caused the gravity to be a bit higher than optimal for a starter. From now on I am going to make a larger starter of at least 1 liter (2 liters preferably) and be sure to keep the gravity at about 1.040. I would have made a larger one but the brew shop only had 500ml Erlenmeyer flasks in stock. I did not take a gravity reading from this starter but I am assuming the gravity was high due to the ratio of DME to water that I used. The optimal ratio of water to DME is 10:1 (1 gram of DME for every 10 ml of water) my starter was approx 10:1.2. Not too bad but a little high none the less. I do plan on making a starter for all brews from now on and eventually I would like to get a stir plate.

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