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NHC take-away(s)

MaltLicker

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My biggest take-away from the NHC seminars I attended is stir plates and oxygen. 

It's all about getting the cell count close, and to get close, the cells have to reach a certain size in diameter and the membrane has to have the resources available before the cell will commit to budding, so nutrients/oxygen/sterols and such are critical for the cell growth that happens in the starter and the fermentor.  Stir plates bring in oxygen, release CO2, and keep the cells in constant contact with the resources.

I also heard a logical explanation of why the yeast MFRs say not to start dry yeast.  A fresh dry yeast package already has 200+ billion cells, and 200+ billion cells in a typical starter would create competition, and few of those cells would reach the size needed to bud, so we'd just be draining the resources the MFR pumped into the package for very little gain, and possibly loss in vitality.  If you need more cells, buy two packages.

I also got to judge porters with Fred Bonjour (another mod here) and did the mini-BOS with John Palmer, which was very neat.  The winning Baltic was yummy. 
 
I think 200 billion is overly optimistic. The process of drying out the yeast without killing it must be challenging from a quality control standpoint because I have had frequent enough troubles with dry yeast to always make a starter from now on.

Saying they will fight it out is odd because that is exactly what wyeast smack packs do with the nutrient pouch kinda. They would reach 'budding size'? when they get put into the 5 gallon batch, it's not like they would harm each other in the couple days it would take to make a starter.

NHC sounds neat, How many judges does it take to eliminate a beer?
 
It is a fuzzy number, but I've seen numerous places that explain (i.e., JZ's site, below) that there are about 20 billion per gram, so about 230BB at absolute optimum assumptions in a 11.5g package.  It declines from there based on strain and handling.  Fermentis states only 6BB per gram on their spec sheet, and I've also heard that low number is partially due to their assumption of users just sprinking yeast on the wort. 

My understanding of the smack pack is that small dose of food and nutrient is just to get the yeast going, since it is hermetically sealed with no CO2 release.  It's not really a "starter" environment meant to grow cells; it's more like a wake-up call. 


http://www.mrmalty.com/calc/dry.html
# of grams of dry yeast:
This is the amount of dry yeast needed, in grams, to get a proper fermentation without a starter. It is based on the assumption that there are 20 billion viable yeast cells per gram of dried yeast. While there are 20 billion cells, you'll find that many manufacturers will state other numbers on their products. The number on the products is the guaranteed minimum viable cells per gram. The reality is somewhere between 20 billion and that number, depending on the yeast strain and how the yeast was handled. Use the production date to calculate the viability of the yeast, which should get you fairly close to the correct number. If you don't have the ability to weigh by grams, don't worry. Use the number of packs below and estimate the amount. That will be OK.

 
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