I need help with some old wyeast 1007

I have a stir plate (1.5L w/170g light dme) going since last night with wy1007 dated 11/21/11. MR. Malty says that it is 35% viable and that I need two of these packs. I am brewing tonight and don't want to buy another pack if I can salvage this one. The yeast activity was very minimal this morning when I checked it. If this doesn't work, I'll just pitch dry.

I am wondering if I can just boil up another batch of sugar water starter, decant the first starter and add to it to the second starter followed by a stir plate until tomorrow morning before pitching. Sound like it would work as good as 2 packs?

No. Sugar water is not a good medium for making starters. Yes, you need more viable yeast to ferment your beer than what you have in that old pack. No, you won't do yourself any favors by prioritizing yeast numbers over yeast quality. The yeast need to be healthy in order to do a good job fermenting.

What you have here is a timing problem. You will be perfectly fine if you wait a couple of days to brew. Also, you *would* have been fine if you had set up that starter a couple of days ago. IMHO, you have to choose: 1. either brew later and use this starter when it is finished, 2. Use the dry yeast or 3. pitch the whole starter tonight (this is very likely to be an underpitch).

Another idea just occurred to me. If your sanitary technique is VERY good, and you have a temp-controlled freezer, you could chill your wort down to 32F for a day and wait for the starter to finish. It's a little risky, but sufficed for me once in a pinch.

Sardoman said:

No. Sugar water is not a good medium for making starters. Yes, you need more viable yeast to ferment your beer than what you have in that old pack. No, you won't do yourself any favors by prioritizing yeast numbers over yeast quality. The yeast need to be healthy in order to do a good job fermenting.

What you have here is a timing problem. You will be perfectly fine if you wait a couple of days to brew. Also, you *would* have been fine if you had set up that starter a couple of days ago. IMHO, you have to choose: 1. either brew later and use this starter when it is finished, 2. Use the dry yeast or 3. pitch the whole starter tonight (this is very likely to be an underpitch).

Another idea just occurred to me. If your sanitary technique is VERY good, and you have a temp-controlled freezer, you could chill your wort down to 32F for a day and wait for the starter to finish. It's a little risky, but sufficed for me once in a pinch.

Click to expand...

I meant more dme btw not table sugar. You are saying that the yeast need to be higher quality not higher numbers. If the yeast finishes up with the current starter, then I should still step it up to make the Mr. Malty numbers, right? I might just brew the batch with dry yeast that I was saving for tomorrow tonight so that I could let this starter hang out. Would it be better to let it hang on the stir plate as is until tomorrow morning (40 hrs total) and then if active at that point step it up with 150 g dme in 1.5L for 12 more hours on the stir plate (52 hours)?