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If you go with option A you'll probably be fine. It seems to be very common for starters to be made with only DME and water, and the beers seem to come out just fine. But, Although there is some Free Amino Nitrogen (FAN) in malt extract, there is not enough for growth of the entire biomass...

I'm glad to help. Personally, I wait about two weeks and keg it. Because it's in the fridge, and there is a pressure regulator if there is any further fermentation, it's not a problem. I don't check gravity in the fermenter to minimize the chance of contamination. However, if you are...

Let's assume your fermentation temperature was mostly between 70°F and 77°F. (70+77)/2=73.5°F = 23°C Ale fermentation temperature is normally about 65°F. 65°F = 18°C Relative growth rate is fairly linear with temperature[1] and fits the following function: rate = 0.040915 * temperature...

Sorry about that. If you don't have Excel running on a Windows machine I've heard it doesn't work well. What temperature did you ferment at? I'll plug in the numbers for you.

http://www.woodlandbrew.com/2015/02/starter-calculator.html Try this calculator to see how long it might take. It is reasonable that it is nearly done.

If you want to "fix" these batches you can add maltodexrin. It's the same sugar that is produced from a higher temperature mash. For the next batch, I agree with the others, mash higher. If you aren't doing a "mash out" then you might want to add one by bringing it to 160°F after the sac...

If you pressure can the wort it should last for a very long time. If you let it cool with the lid ajar I would guess it would last about a month or two in the fridge.

Yeah, braukaiser primarily makes lagers. You can this calculator to give you an idea of how long it will take to grow the amount of yeast you want: http://www.woodlandbrew.com/2015/02/starter-calculator.html

This sounds like a very reasonable number. Im always looking for more sources to back up rules like this. Do you have a source for this number? To the ops question. You should be fine. Dry yeast is good 2 years out of the refrigerator, and 3 yeast in. From packages that I have purchased...

A starter made with 100g of DME will grow between 100 and 150 billion cells dependent mostly on the amount of FAN. [1] The cell density of settled slurry is about 1.5 billion cells per ml. Viability doesn't drop much over time in the refrigerator. [1] Schulze, Ulrik, et al...

Agitation of the fermenting beer will speed fermentation. In my experience this is the main reason that stirred starters grow yeast more quickly than still starters. It's more common to swirl or shake the fermentor thought fermentation when making mead. Im not sure why it isn't more common...

Using the same amount of malt extract and a little less water will yield the same final cell count. The final ABV is what really limits the starting gravity when starting with a a large amount of yeast, as is done in a starter. You could do 100g in 700ml which is about 12°P and will end at...

Most of the time aeration is not a problem even with yeast that has been stored for longer than a week. It's the same with a vial of yeast you might buy. Oxygen requirements are strain dependent. If you do have a problem, or just want to play it safe, you can just aerate twice. Pour the wort...

It's a good book, but keep in mind that it is just two people that wrote it. While they have a ton of experience, not everything they say is in line with peer reviewed papers on the subject. I guess my point is that it is not the yeast bible.

Yeah, a few days is all it takes. I could dig up a paper if you want. The way many breweries get around this is by aerating twice. Yeast will metabolize the oxygen in a few hours. There is a paper and a presentation I could dig up on this if you are interested.

Ideally the yeast should be tempered to the wort temperature, and the wort temperature should be the fermentation temperature. Because of the temperature change the yeast are going to expend more energy adjusting their metabolism than they would have if they were only adjusting to the wort. In...

Sounds solid. Saccharomyces Cerevisiae optimal propagation temperature is just over 30°C. At about 40°C yeast begins dying faster than it grows. You can estimate how many cells you have by measuring the settled yeast. When cultured with DME it's about 2 billion cells per ml.

Agreed. 33°C is the optimum temperature for s. cerevisiae. [1] However, at this temperature there will be increased Ester production. [2] But, this early in the fermentation the yeast will still be in the lag phase and not producing esters. But, temperature changes will cause heat shock...

To elaborate on glycogen and sterols: Glycogen allows synthesis of sterols without pulling in sugar from the wort, and sterols aid in membrane permeability which helps in regulation of compounds in and out of the cell and is required for cell budding and growth. If the sterol level drops to...

Here is a good paper on PCR: http://femsle.oxfordjournals.org/content/221/2/249.abstract And Siebel offers PCR testing for about $100 when I asked. You'll have to contact them for details, but here are the services: https://www.siebelinstitute.com/services/yeastmaintenance/