orchidfanatic,

That is always fun and I am glad you asked. I know quite a bit about this.

First, this is Mycology just like mushrooms so no need to move it.

to answer your first question

Quote:

---

what do they look like on agar?

---

They look like this



Now that one was a contamination in a Ps. Cubensis plate but it is the only picture I had.

Quote:

---

how to keep master slants alive?

---

Quote:

---

making a starter from a yeast culture to pitch into 5 gallons of beer

---

The easiest way is to empty the culture tube of suspended yeast into a sternal wort, cap with a fermentation lock and let them do there job.

So, Lets assume you wanted to work with them on agar, in the picture above each of the dots of yeast are called blooms. You would open the plate and using your inoculation loop or inoculation needle you would remove one of the blooms and transfer it to another plate. They grow within the same parameters as mushrooms so drop the plate into your incubator and wait. When you get blooms that are about 1mm to 2mm in size you will want to take and scrape them off with your inoculation loop and put them into your sterile water culture tube. One good streak can make lots of culture tubes. If you are working with wild yeast each bloom may be a different strain with different properties so you will need to culture them out and test them. If you are working with a commercial strain they should all be the same strain. You should also note that yeast change after repeated culturing and you can end up with new and unique strains from them.

Now to prep a tube for making beer you will need to start by making 1 liter of wort. This will be malt extract and dextrose. I mix it to an SP. GR. of .030 For a sterile culture you will want to autoclave the wort and let it cool to around 85F-90F. Then add the contents of 1 culture tube. It will take 24 to 72 hours before you have enough yeast to reach the point that you can see fermentation. Once you get there, you can pitch the starter culture into your 5 gal carboide and you will be up and running.

You may also note that if you buy a master culture, you can dip your inoculation loop into it, streak it onto agar, grow it out, and make lots more master tubes from it.

The shroomery vendor DarkSpores sells a couple of different masters here
http://www.darkspores.com/catalog/index.php/cPath/26_32_41

as well as most of the supplies needed.

I hope no-one gets upset at me for plugging a vendor.

Quote:

---

fastfred said:
There is no real selection for yeast. They are all assumed to be more or less homogeneous.
-FF

---

Only commercial strains. If you catch wild strains each will be different. Some reproduce faster than other, some produce more CO2, some produce more alcohol, most provide a slightly different flavor, etc. The problem is that you have to isolate and grow each to test for the traits.

From a Commercial standpoint

Bread yeast produce more CO2 than alcohol.
Of the bread yeasts there are several commercial variates that are fast growing, as well as sour dough yeasts that produce some strong flavors.

Beer yeasts produce more alcohol.
The list of beer yeasts is long and they break up into two main categories. Ale's and Lagers (Based on the temperature and method of fermentation {top or bottom fermentation}). Each beer yeast adds a unique subtle flavor to the beer. So each is different.
Wine yeasts can handle higher alcohol concentrations and each adds a unique flavor to the product. That is why wine from France tastes different that wine from California.

Yeast can be lots of fun to play with! I have a friend that has cultured a yeast that survives at alcohol contents above 30% Provided he makes a wort that is high enough in sugar, he can ferment drinks that are on par with some distilled liquors! Not to count that you get more our of it when you distill it.

Hope this helps.

Quote:

---

Cyber said:
If you catch wild strains each will be different. Some reproduce faster than other, some produce more CO2, some produce more alcohol, most provide a slightly different flavor, etc. The problem is that you have to isolate and grow each to test for the traits.

---

how do you catch wild strains?  this a great thread.  im really intereseted in how you can get wild strains.  can you post any info or links for catching and keeping wild yeast?  you seem to know alot tnx for sharing!  someday i want to live off the grid and do everything myself i can  

yeast extract is used in mycology sometimes i think and didnt TMC and Agar say somthings about mycleium eating those little buggers like bacteria and yeast?  could yeast be used for mushroom growing some how?  like food?

what about finding out what types (strains?) they are?  if you catch wild strains is there a way to tell what you have once youve isloated the bloom (you called it?) by transferring blooms over 1-2mm to new agar?  for beer you need Saccharomyces cerevisiae right?  or can you use any yeast that can ferment?

tnx much bro!!! you rock with the info!!!