New Video – Starters from Slants or Plates
Check out the latest instalment in my “Your Home Lab Made Easy” video series, where I demonstrate how basic microbiology techniques can be employed in the home brewery.
In this instalment, I demonstrate how to create a yeast starter beginning with yeast on an agar plate or on a slant. This is a critical skill you will need to master if you plan on culturing your own yeast for use in your home brewery.
Hello, I have started my yeast bank thanks to this blog, it’s always fascinating to see a mini Krausen in a test tube inoculated from a slant! I have a question regarding pitching rates: I mostly do 5L batches, so instead of doing a 2L starter I will do a 0.5L on a shaker plate in 1.040 wort. Is it reasonable to assume that I would get about the same pitch rate as I would with a 2L starter in a 20L batch? I couldn’t find any information on wether the growth rate scales linearly with the starter volume.
You should end up close enough to not notice much of a difference. The growth isn’t 100% linear as starter size increases, but it is close enough at the scales homebrewers work at.
Hi Bryan,
thanks for sharing this video. One question about you opinion. What method do you prefer for yeast banking – agar (slants/dishes) or freezing? Or is it good to keep both?
I prefer freezing as it is less work as you don’t need to re-culture the yeast as often. However, I manage a bank of over 500 yeast strains; for a smaller home collection slants are probably easier.
I have a small collection. But I am always worry when innoculating, that the culture inside the 1,5ml eppendorf tube will melt and I harm the culture when refreezing. Might be I am too scary about that, but I am training to be able to store local wild bugs and definitely do not want to ruin my work by some stupid mistake…
Do slants have any significant advantage over frozen culture?
Refreezing can be an issue; ideally with frozen stocks you either want to package them in single-use sized aliquots, or you want to use a bacteriological loope to scrape a small amount of the frozen culture into a tube, and then return the frozen culture to the freezer before it thaws.
Slants are stored in the fridge, or room temperature, and thus you can take yeast from them whenever you want. So long as you work in a sanitary fashion, you should be able to repeatedly use a slant. The biggest downside is that they require re-culturing every few months (if using tape-sealed slants) to every 1-2 years (if using slants under mineral oil). A frozen culture is generally good for 2 years or longer in a home freezer.