Reference 2:35 minutes /5:11 minutes Please specify ratio of Methylene Blue to distilled water. Also clarify if the Methylene blue is 1%. (follow up question from video #1). Thanks for your videos.
For a truly accurate count, it seems one would need to mix the original yeast jar so that it is homogeneous before removing a sample to count. However for the purposes of dilution and staining, this is helpful.
Hi Nick. I agree. That is a good idea. For home brewers that is no problem, but when you are pitching from a keg or a yeast brink then you usually just take a quick sample from the sample port. When I do this at home I usually shake it up, pull out my sterilized pipette and draw a sample.
Hi there, I have a question. My partner enjoys brewing his own beer (from scratch) where there are plans to take his passion to the next level and hopefully open up a brewery in the next few years. I myself am a scientist in the field of ecology but have quite a bit of experience in the lab and with microscopy etc... so we have been observing Sacromyces under the microscope in the fashion which you demonstrate in your video. We purchased all of the necessary equipment to begin counting the yeast cells i.e. hemocytometer and cover slips however we seem to be struggling with the cleanliness of the cover slips; as the manufacturing process has left them cloudy and we have no way of cleaning them- other than purchasing additional products and potentially volatile chemicals. How do you clean your covers slips, do you have any instructions and or additional advice you can offer on this subject? The cloudy cover- slips are the only thing stopping us from performing a yeast cell count.
I watched your video. Great job! It inspired me to order the same equipment so I could start reusing my yeast. However, I cannot get the PentaView microscope to focus. My hemocytometer lines are fuzzy no matter what I do. Do you have any suggestions? Because on your video the image is so crisp.Thanks for any insight!
I would start with the lowest magnification and focus it there, then move to the next, refocus, and so on. It could also be that the light filter underneath is set incorrectly. If you haven't seen it yet then turn it upside down and give it a look. Another problem could be your actual hemocytometer. Initially, I purchased a cheap, $20 kit with a couter, cover glasses, and the hemocytometer. It worked well, but the lines were not straight, so when I moved up and down, it would also go right and left. I, therefore, purchased a new one. This one cost $95 on ebay. It was listed at $125 or best offer. I see one is listed there now as well for $124.95 or best offer. The brand is Hausser Scientific. It is crystal clear and I love it. At least a 10-time improvement over the cheaper version.
Here are the procedures for serial dilution, from the yeast book: Serial Dilution Many times your lab work will require a specific concentration of yeast cells. For example, it is impossible to count cells without first getting the right concentration of yeast. Too little or too much, and you will not be able to get an accurate count. Of course, the amount of dilution needed depends upon the starting concentration and the desired final concentration. If you need to do more than a 1:10 dilution, it is best to do a serial dilution for accuracy. Materials • Sterile, capped 13 x 100 ml tubes with 9 milliliters of sterile water in each • Sterile pipette • Pipette pump Procedure 1. Set up the test tubes in a rack for successive dilutions (depending on your desired dilution rate). 2. Label the dilution rate of each tube and loosen the caps. 3. Shake up the yeast and pipette 1 milliliter of yeast into the 9 mm water tube. Pump the pipette several times in the tube to mix up the yeast and water. This creates a 4. Using the same pipette, remove 1 milliliter of this diluted yeast and place into the next water tube. This creates a 1:100 dilution. 5. The next dilution makes 1:1000, which is the usual dilution for counting yeast slurry. 6. You can continue with more dilutions if needed. Hope that helps!
Reference 2:35 minutes /5:11 minutes Please specify ratio of Methylene Blue to distilled water. Also clarify if the Methylene blue is 1%. (follow up question from video #1). Thanks for your videos.
Thank you, it's a very useful video. What is the ratio of water and methylene blue did you mix?
Please see my video about making methylene blue:
th-cam.com/video/3nkPant08b0/w-d-xo.html
For a truly accurate count, it seems one would need to mix the original yeast jar so that it is homogeneous before removing a sample to count. However for the purposes of dilution and staining, this is helpful.
Hi Nick. I agree. That is a good idea. For home brewers that is no problem, but when you are pitching from a keg or a yeast brink then you usually just take a quick sample from the sample port. When I do this at home I usually shake it up, pull out my sterilized pipette and draw a sample.
Hi there, I have a question. My partner enjoys brewing his own beer (from scratch) where there are plans to take his passion to the next level and hopefully open up a brewery in the next few years. I myself am a scientist in the field of ecology but have quite a bit of experience in the lab and with microscopy etc... so we have been observing Sacromyces under the microscope in the fashion which you demonstrate in your video. We purchased all of the necessary equipment to begin counting the yeast cells i.e. hemocytometer and cover slips however we seem to be struggling with the cleanliness of the cover slips; as the manufacturing process has left them cloudy and we have no way of cleaning them- other than purchasing additional products and potentially volatile chemicals. How do you clean your covers slips, do you have any instructions and or additional advice you can offer on this subject? The cloudy cover- slips are the only thing stopping us from performing a yeast cell count.
Fortunately, I have never had that experience. I would suggest a different supplier.
Okay, we are in Australia what products do you use? We might just get the same products you use?
Never mind, I noticed that you have them above :)
I watched your video. Great job! It inspired me to order the same equipment so I could start reusing my yeast. However, I cannot get the PentaView microscope to focus. My hemocytometer lines are fuzzy no matter what I do. Do you have any suggestions? Because on your video the image is so crisp.Thanks for any insight!
I would start with the lowest magnification and focus it there, then move to the next, refocus, and so on. It could also be that the light filter underneath is set incorrectly. If you haven't seen it yet then turn it upside down and give it a look.
Another problem could be your actual hemocytometer. Initially, I purchased a cheap, $20 kit with a couter, cover glasses, and the hemocytometer. It worked well, but the lines were not straight, so when I moved up and down, it would also go right and left. I, therefore, purchased a new one. This one cost $95 on ebay. It was listed at $125 or best offer. I see one is listed there now as well for $124.95 or best offer. The brand is Hausser Scientific. It is crystal clear and I love it. At least a 10-time improvement over the cheaper version.
Thanks. I ordered the brightline hemocytometer you recommended and it made a world of difference!
Casual Animal I am glad it worked out. It is high quality. Check out a Google search for full price. I think it is around $600!
how concentrated is the MB solution?
Thanks very helpful.
Thanks, Kyle. Please let me know if you have any questions, and do download the excel spreadsheet in the description section.
Would it not be more accurate to put 1ml of yeast slurry in 99ml of water directly?
FDK any error would just have a much larger impact. Give it a try both ways and let me know how it works for you. I will do the same.
wouldnt 1 mL in 9mL be a 1 to 9 dilution?
Here are the procedures for serial dilution, from the yeast book:
Serial Dilution
Many times your lab work will require a specific concentration of yeast cells. For example, it is impossible to count cells without first getting the right concentration of yeast. Too little or too much, and you will not be able to get an accurate count. Of course, the amount of dilution needed depends upon the starting concentration and the desired final concentration. If you need to do more than a 1:10 dilution, it is best to do a serial dilution for accuracy.
Materials
• Sterile, capped 13 x 100 ml tubes with 9 milliliters of sterile water in each
• Sterile pipette
• Pipette pump
Procedure
1. Set up the test tubes in a rack for successive dilutions (depending on your desired dilution rate).
2. Label the dilution rate of each tube and loosen the caps.
3. Shake up the yeast and pipette 1 milliliter of yeast into the 9 mm water tube. Pump the pipette several times in the tube to mix up the yeast and water. This creates a
4. Using the same pipette, remove 1 milliliter of this diluted yeast and place into the next water tube. This creates a 1:100 dilution.
5. The next dilution makes 1:1000, which is the usual dilution for counting yeast slurry.
6. You can continue with more dilutions if needed.
Hope that helps!
Have you ever tested an automated yeast counter like the Oculyze?
th-cam.com/video/520vIGwgbNY/w-d-xo.html