In the thread "Yeast starter - airlock or tinfoil
" the general consensus is that tinfoil on starters is superior to airlocks/bubble locks because tinfoil lets oxygen into the container and thus the yeast will multiply and perform better than a container with a bubble lock.
I'm not convinced. I'm not in any way saying that tinfoil doesn't work; it does and it works well. But I'm not sure that the claim that "because oxygen gets into the container the yeast multiply more and one can get a bigger starter" is true. So I've decided to conduct an experiment to test my hypothesis that yeast starters with bubble locks perform as good or better than than starters covered with tinfoil.
The Experiment to test my hypothesis:
1. Make two (2) one liter starters. The preparation of each starter will be created by making 8 cups of water and 2 cups of DME. After the wort has boiled and cooled I will mix thoroughly and divide the wort evenly into two jugs. (thanks StoneHands and kh54s10)
2. Each starter will be transferred to sanitized half gallon jugs that are identical in size and shape.
3. When the temperature in both starters is below 80F I will pitch the exact strand of yeast in the exact quantity into each of the containers.
4. I will swirl/shake each starter the same number of times i.e., if I swirl one starter 5 times then I will also swirl the other starter 5 times, no more no less.
5. Each starter will work for 72 hours.
6. Before I seal each starter and after 72 hours the starters will be measured using a hemocytometer (thanks StoneHands and mewithstewpid)
One jug will be covered with tinfoil.
The other jug will have a stopper and a 3 piece bubble lock.
Hypothesis - The starter with the 3 piece bubble lock will produce equal amounts of yeast (or more) as the starter with tinfoil.
1. I do not have 2 stir plates and therefore they cannot be used in this experiment.
2. I have to learn how to use a hemocytometer properly and accurately.
So now I have to ask you all how to make this experiment better. I need a way to measure yeast counts but I'm not sure how to do it in the best way possible. Any kind of suggestion would be helpful and will greatly influence how I measure the yeast count. Anything else that you see to make this experiment better is welcomed!