Yeast Cell Counting 1 - More Videos At www.coloradoboy.com

[@ekapada]

Yes, different concentrations will work. It is only needed for yeast strains that are highly floculative. And then, only about a drop or two is needed. You can tell once you do your first dillution, because it is obvious that it is clumping.

[@mandieherdrick9624]

Hi! Can you tell me which hemocytometer you prefer?

[@thorhale]

I assumed you would do a yeast count on something like a beer at different stages of fermentation, and also do a graham stain to check to infections.

[@ekapada]

We are just a pub, so that is not important. When I had a packaging brewery I did filter tests, o2 testing, gramstain, swab tests. I have never tested yeast cell counts after fermentation kicked off. If you are selling your beer just in your tap room and you are VERY clean you needn't worry about a lab.

[@thorhale]

ekapada so then your are testing a yeast cake so you know how much to pitch?

[@vikramjitsingh4538]

what a simple and helpful video.....cheers thank you....

[@ekapada]

Colorado Boy in Ridgway, CO

[@krismarch3718]

can you post what scientific tools you are using? Thanks!

[@ekapada]

You need a hemocytometer, two 10 ml test tubes, and lately instead of pipets, I have been using a 10 ml syringe. To make a 100:1 dilution, add 9 ml water to 1 ml yeast. Shake, then take 1 ml of that and add to 9 ml of water. This 100:1 will make it easier to count cells. Your micoscope needs to have a 40x power, when coupled with the 10x eyepiece it give you a 400x, which is needed to count yeast

[@estherwilby4906]

If you didn't harvest enough yeast to re-pitch, is it possible to add some dry yeast when you do the re-pitching?

[@ekapada]

Yes, but I wouldn't use that yeast again as it will change its original characteristics.

[@riskyb250]

What brewery/brewpub is this at? Great video!

[@micromesh120]

How many megapixel does your camera/screen on the microscope have?

[@ekapada]

I would recommend just getting a regular microscope. Should have a power of 400x (40x with a 10x eye peice). Try eBay - should cost you about $140 and work better than this one with the screen. I only use the one with the screen for teaching at our immersion course.

[@jibba0202]

10:1 ratio or 9:1 ratio?

[@ekapada]

It's 10:1 it's seems counter intuitive but 1 ml slurry to 9 water is 10 ml solution so the density of yeast to water is 10:1. When I was at Siebel everyone had the same question

[@jibba0202]

+ekapada Sorry i dont understand that at all. If you have 9 parts of something and 1 part of something, that would be a ratio of 9:1. Totaling 10 parts.

[@ekapada]

I wouldn't lie. That's the way they taught me at Siebel and they have bee teaching brewing for over 150 years

[@jibba0202]

I never for one second said you lied. If what you said i correct i would appreciate an explanation so i can learn.

[@ekapada]

Don't worry, I was saying that in jest. I'd be happy to answer any of your questions. Go to coloradoboy.com and email me. Cheers, Tom Hennessy