Creating The Perfect Starter

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Creating The Perfect Starter

Postby HumbleOpinion » Mon Oct 20, 2008 2:12 am

So you have been making a starter and getting good beer, but now you want to move on and up with the big boys eh? Well this post is for you. Here I am going talk about creating the perfect yeast starter.

In order for me to convey this information so that everyone can relate to it we have to assume a couple of things. First, we will assume that we are brewing a beer that will have an OG of 1.048. Second, we will assume that we are brewing 5 gallons of wort. Third, we will assume that we are making an ale. Fouth, we will assume that we DO NOT have a stir plate. You may ask why not, and the answer to that question is simply that whatever numbers for yeast amounts due to growth in a starter I state here, you can gaurantee that they will be higher with a stir plate. Fifth, we are using liquid yeast. Finally, we will assume that we are going to create a 2000ml or 2 quart starter.

So let's get started!

The first thing that that you need to know when making the perfect yeast starter is how much yeast you are going to need to properly ferment your beer. Yes, I did say properly, but lets understand that when I say properly I don't mean that you are doing it WRONG. I just mean that there is better way that will yeild better results. This also means that you will probably see things happen in your beer that you are not used to seeing. More on that later. So pretend that you are a brand new brewer and put all of your preconceptions in the closet and lock the door.

The proper pitching rate for beer deffinatly varies, but not in the way you may think. It simply has to deal with the OG of your wort. Now most brewers are not going to wait until they have brewed and taken their OG to determine how much yeast they need to pitch. That being said, useing your target OG is just fine. Since we already know what our target OG is we can apply the formula and it goes like this.

You need to pitch 5 billion cells of yeast for every point of gravity or 20 billion yeast cells for every degree plato. SIMPLE RIGHT?!?! I know, you saying yea that's frikkin great, but how in the world do I know how much yeast I have or are going to have? I don't have a darn microscope! Well if you are using a Wyeast activator pack then you know if you smack that baby and let it do its thing you are going to have 100 billion cells of yeast. If you are using a White Labs yeast culture then you can assume that you will have anywhere from 70 to 140 billion yeast cells according to their website. So with this knowledge we can say that an Activator pack & a White Labs tube used correctly can properly ferment 5 gallons of 1.020 wort with the amount of yeast that is in that culture.

So how do we get from approximately 100 billion yeast cells in our yeast culture to the necessary 240 billion yeast cells required to ferment out 1.048 beer? (Remember the formula 48 points of gravity X 5 billion yeast cells = 240 billion yeast cells)

We make a starter of course!

So I can tell you that I don't know the science behind the volume of wort required to grow a specific number of yeast, but I can tell you this. 2000 ml or 2 quarts of 1.020 - 1.040 wort when innoculated with either a Wyeast Activator Pack or a White Labs yeast culture will yield approximatly 240 billion yeast cells. Now I intend on finding more information as to why this is and posting it at a later time, but unless you intend on setting up a laboratory in your garage I don't think you need the information.

So now lets put it all together.

The first thing that you want to do is pull your yeast out of your refrigerator and bring it up to room temperature. If you are using an activator pack then go ahead and smack it now as well.

Second we boil our wort. Whatever it is. It really doesn't matter. If it is sugar, the yeast will eat it. That being said don't go an use some weird stuff just because you can. Let's not make this any more complicated than it has to be. Stick with the simple stuff. Table sugar, DME, LME, Corn sugar or anything of this nature. If you use real sugar or corn sugar then you will not have to deal with a "hot break" or a "cold break". If you are a purist or going for reinheitsgebot then you have to use DME, LME or brew a starter wort that you pastuerize and keep around for just such an occasion.

This would be a good time to talk vessels. For a long time all I was ever using was a 2 quart sauce pot to boil my wort in and 1 gallon glass wine jug to put my starter in. I now have an Erlenmeyer made of borosilicate glass that I can use right on the stove. This is obviously convenient because you can use one vessel for the entire process. Also you don't have to sanitize it because you are about to boil liquid in it. If you do not have access to an E-Flask then a glass jug of some sort will be just fine. Just make sure that you sanitize it first!

So now that you are getting ready to boil make sure that you measure enough of your sugar in order to get a wort of 1.020-1.040. I personally have been using 1C Light DME to 4C of water and getting around 1.030. That is a nice happy meadium for me.

When you are done boiling you can just cover your wort with some aluminum foil and set it on your counter to cool. I like to set mine on a wire cooling rack, but its not necessary. If you are picky about your break material then you can chill it down until the cold break drops out, decant the good wort off, then bring it back up to room temperature, and then pitch your yeast. That just seems a little crazy to me though.

So you may have guessed that the next step is to add your yeast, and you would be right, however. In order to make the perfect starter you are going to need to throw some yeast nutrients in there. No, this is not necessary but it will help your boys out and you'll probably have more yeast in the end.

Ok, we have our yeast in the starter now what?

Oxygenate! If you have an airstone and an oxygen tank then you are golden. Simply run pure O2 into the solution for about a minute. If you are really dedicated then you can run O2 into the solution for a minute every 2 hours or so for about 6 hours for a total of 3 O2 additions. If you don't have O2 but you do have an airstone and a pump then you can run your stone for the entire process.

If you don't have a stone at all then you can vigorously shake your vessel, covered tightly of course, for a good 5-10 mins. I like to go more towards the 10 because this is a highly inefficient way of oxygenating anything.

Once your starter is fully oxygenated then it will be done with its lag phase (the phase in which the yeast are growing) within 6-12 hours. In 12-24 hours your starter should be fully fermented out.

It is best to pitch your starter at one of two points. The first is at full crousen. This is the peek of the log phase (fermentation) when that creamy white foam collects at the top of your fermentation vessel. If you want to to pitch at this point then you need to pitch the entire starter, wort and all.

If you want to pitch after fermentation is complete then decant off all of that nasty stuff that may be called beer. Leave a little liquid so you can swirl your slurry and then pitch that.

One more thing. Make sure you are growing your yeast and pitching your yeast at the same temperature. Yeast are really finiky. They don't like changes in temperature. Especially lager yeast. Though lager yeast love to live and ferment at about 80 degrees farenheight. Even more so than ale yeast. Unfortunatly at this temperature they throw off really nasty flavors and compounds, but that's another post.

Last but not least. If you are brewing a beer that is of higher gravity, say 1.060 or higher, then you need to make a bigger starter. The reason for this is because the more sugar that is in the beer the more you are going to stress your yeast. It would be like me asking you to stack a pile of 1000 bricks into a pyramid shape by yourself. I am sure you would be stressed out! If you had 15 others helping you though it wouldn't be so bad. This is also true for the yeast. Remember they are living breathing creatures as well.

So, exactly how much bigger? Well just go by our trusty formula. 5 billion yeast cells for every point of gravity (20 billion for every point plato). Knowing this you can use your 2000 ml starter amount as a benchmark. You can figure that if 2000 ml of wort will give you 140 billion additional cells then 3000 ml would give you another 70 billion and 4000 ml (approx. 1 gallon) would give you another 140 billion. Get it?

Remeber it is VOLUME that dictates the amount of yeast. Not the strength of the starter. If you make too stong of a starter you are only going to stress out your yeast.

If you are wondering about lagers the simple answer is double everything. That means use 10 billion yeast cells for every point of gravity (40 billion for plato). This means that if our beer was a 1.048 lager then you need to be making a 4000 ml or 1 gallon starter. You should be growing these boys at the temperature you are going to lager at as well, unless you can bring their temperature down very slowly. 1-2 degrees an hour.

I hope this helps all of you brew better beer. If there are any questions or comments please post them in this forum.
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HumbleOpinion
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