Stepping Up Starters - WHILE USING A STIR PLATE

I don't know the answers here, but I'm replying to mark this thread because the topic interests me. Thusfar I haven't needed to step up starters, but soon I will be at double capacity at ten gallons, so again, I'm interested.

I know I could google it, but BA tends to give great answers to this sort of question.

 

My understanding of stepping up a starter is that you need to crash it, decant the beer, then add your second volume of wort and continue.

I havent stepped up one yet, but I will need to do so when I brew a bock in the next month or two.

Yeastcalc.com

 

This seems like the best method - getting the "spent wort" off the yeast before stepping up, so when you pitch into the second wort you'll have maximum possibility of growth.

 

Seems like it would be best to just add to it imo. It's only been under a day and I know my first starter *EDIT: with Conan* I did recently took a while to really take off, albeit without a stir plate. Either way the yeast are still young and probably still multiplying so the most active yeast will still be in suspension. no reason to shut them down before adding more.

 

I definitely suggest that calc too. The more yeast you have vs wort volume, the less growth that will occur. That site has all the homework figured out for you.

 

This is the main reason I crash/decant each step of my stepped starters. How important it is depends somewhat on the relative sizes (to each other) of your steps.

 

According your numbers I think you will get about less than 245 billions cells, it is half cells you need for 10 gals of an average beer with an OG of 1050.Maybe I am wrong but I think you are going to underpitch your batch.

 

80 billions????. Think that when you pour a slurry of a vial of liquid yeast you have almost 100 billions cell yeast, I think that amout is not comparable with those dregs you stated before.IMHO

 

you might well need multiple step-ups when starting with dregs. more commentary sought by those with more insight

 

Do you have access to a cheap light microscope ($40 online), methylene blue (Can get at pet store) and a hemocytometer ($10 online)? Thats probably the best way to do it... you can send me a sample and I can count it, then grow up some conan for myself

 

He has stated he has made a 200 ml starter using these dregs, that doesn´t mean he can get 80 billion cells as the final number of his first step

 

seems this initial number is qutie questionable and some reasonable means of proceeding with this level of uncertainty must be determined

 

Method 1 or 2 will work. I use method 1 myself and cold crash at the end. If there is any question about how much yeast I grew I will decant off most of the wort and pour into some sort of graduated bottle or jar and estimate based on the volume of yeast.

I think those step up calculators work more like guidelines to get you inside an acceptable range of yeast cells than to tell you an exact number of yeast you will obtain. Everyone's growing conditions will vary slightly , or greatly in some cases.

I step up starters for just about every beer I make. My starter wort comes from an extra 1-2 gallons I sparge at the end of the previous brewday with a dash of yeast nutrient. My OG after I boil down is somewhere in the 30s, so not very exact.

I typically start 1/4 to 1/5th of a Wyeast Activator pack into 500ml and let it go around 24 hours. I eyeball it to decide when to step up. I look for lack of CO2 bubbles, color or in the case of 1968 egg drop soup.

Then I will add the rest of the starter wort to get me the number of cells I need, but a good rule of thumb is to step up 1 to 5 volumes. I would not blink going from 500ml to 3500ml.

I know by doing this I will consistently end up with around 200 million cells per ml of starter. My point of this description is that growing yeast is not as an exact science as one might think. Can you be exact about it, sure. Do you need to be, not really.

Here is a good link about everything you ever needed to know about starters.

 

Both methods can work.

Palmer's method: http://www.howtobrew.com/section1/chapter6-7.html

Jamil's method (from Yeast) is to chill/decant/add.

I use a hybrid of the above . . . first step to 600ml is direct addition, then chill/decant for larger steps. This has worked for me.

One word of caution, at the 200ml level it is likely you will miss the krausen rising and falling. You are not really sure the yeast is alive because it happens so quickly. So on blind faith I make my first step. At the 600ml level the krausen is bigger and lasts longer, you are more likely to see it and the off-gassing, also some pleasant aroma. But this may take 3-4 days to develop. I officially "gave up" on my last harvest (Ommegang yeast) after the first step and waiting over 3 days. But I didn't have the heart to pour it down the drain, just walked away dejected. The next morning I awoke to a very pleasant sight of a nice krausen.

As for cell count . . . the calculators do a good job of predicting the growth, but they all depend on you inputting the cell count of your dregs. This is an unclear area. Here are some guidelines that may help:
http://www.wyeastlab.com/com-yeast-harvest.cfm

Much of this is discussed in Yeast, after several recommendations I took the plunge and and use it as my reference. Sorry for the wordiness, if I had more time I could have written a shorter response.

 

What do you do with the other 3/4 of the activator pack?