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That's right. I have seen a significant difference when I failed to allow the temperature to stabilize (about double)

@passedpawn When you platted it was there any determinable difference in the giant colony morphology within the same plate?

Awesome experiment! Are you planning on plating the cells to separate the yeast from bacteria and other fungi, or just going to ferment with the entire microflora? If you are interested in plating you can find details here...

Typically twice as much yeast is used for a lager compared to an ale. (Dr. George Fix came up with 0.75 billion per liter degree Plato for ales and 1.5 billion per liter degree Plato for lagers. This is the number used by most calculators. You can use just about any pitch rate calculator...

I've been collecting some metrics on S-23 for my starter calculator, and have noticed that it is quite slow. On paper saccharomyces uvarum looks very similar to saccharomyces cerevisiae, so what I am seeing may be an isolated case. The maximum growth rate of s. cerevisiae is about twice that...

This has also been my unscientific observation. I am working doing some tests, and research on this, but have yet to come to any strong conclusion. Thanks for the kind words, and your yeast looks great! Can I add this picture along with the other in the main post?

The sediment that take up the bottom 3/4 of the jar contains the yeast. Even with the trub, the cell density in the settled slurry is about the same as if you had washed it. The big difference is that you have about ten times as much yeast.

That looks great! Do you mind if I use that picture on the first post?

There are advantages to both storing yeast in sterile water and storing in beer. Advantages to storing in sterile water: • Cell death is not caused by alcohol. Advantages to storing in beer: • Minimal contamination risk from because fewer processes steps are used. &#8226...

There are advantages to both storing yeast in sterile water and storing in beer. Advantages to storing in sterile water: • Cell death is not caused by alcohol. Advantages to storing in beer: • Minimal contamination risk from because fewer processes steps are used. &#8226...

Here you go: https://www.homebrewtalk.com/bittering-hops-in-15-minutes.html You can absolutely add bitterness post fermentation using a number of methods. You only need about a cup of water, so it's not going to water your beer down much. The pressure cooker will create the same amount...

Fair questions. Fermentis provides a very conservative minimum viable cell count. (assuming you are talking about the 6 billion Viable cells per gram here: http://www.fermentis.com/wp-content/uploads/2012/02/SFA_S04.pdf) 20 billion Total cells per gram is what I have observed ( see here...

Over pitching by a factor of two will decrease bitterness and esters. Under pitching by a favor of two will increase esters. (see mbaa paper on beer quality and pitch rates) However, a difference in pitch rate by a factor of five can still make good beer. The two are just noticeably...

Good question. Those were topped off with water which isn't necessary. if you follow the given procedure it should look like the jars in the image except with beer replacing the water. Similar to a crashed starter.

Mostly yes. This topic really deserves a whole article.

You are absolutely right. Using a yeast calculator or estimating by volume is often off by a factor of two.

Dry yeast is 20 billion cells per gram. If you rehydrate by the manufacturers instructions you'll probably be near 90% viability. If you don't you'll be closer to 75%, and I've seen as low as 50%. (Based on Methane Blue viability staining)

Generally settled slurry is about 1.5 billion cells per ml, although despite what most of the calculators indicate, pitch rate doesn't greatly influence yield.

Lots of hop debris will put you closer to 1 billion per ml, but other than that I would handle it the same as typical slurry.

Thanks everyone! The positive feedback is really a great motivator for putting the effort into posts like this. Thanks for the suggestion. I added a picture. Yes, the time unit is days. It looks like I forgot to include that. The post has been updated. This is an equation based on...