Im making a 5 gallon batch of beer with a 1.078 OG. Is a pint of water and 1/2 cup of DME a big enough starter? I have a smack pack of wyeast, 100 billion cells. Do I need to go bigger? If so how much water and DME do I need to boil? It will also be on a stir plate. Thanks in advance
I use the white labs equation, to keep a steady 1.040 starter use 1 gram per 10ml, so usually I use a 900 ml starter with 90 grams of DME.
Here’s my calculated starter sample volume. (0.00100 billion cells/ml) X (18927.1 ml) X (19 deg Plato) = 360 billion cells (360 billion cells) / (1.2 billion cell/ml) = 300 ml sample I’d say you’re going to need using a 2L flask with 1300ml water and 1 cup DME; I add a 1/2 tsp of Wyeast nutrition to my starters as well. After 48 hours on the stir plate, put the sample in the frig and next day decant to see if you’ve hit the 300 ml of yeast. Do a second starter as needed.
100 billions cells in a 1 pint starter will give you very little growth because the innoculation rate is way too high. This is like throwing a skrawny chicken to a pack of starving dogs . . . nobody gets much of a meal. And, based on date, you most likely have less than 100 billion. Your questions begs for using a yeast calculator. Many good ones, try this: http://www.yeastcalc.com/indexupdate.html If you plan on 5.2 gallons in fermentor, you will need 278 billions cells. The calculator will update your live cells based on date and tell you size of starter, ingredients needed to accomplish, and effects of stir plate. Also a pretty good starter-primer in their FAQs. Good luck.
This is a good resource for starter sizing. I usually shoot for 1 cup per Liter in a starter. http://www.mrmalty.com/calc/calc.html This will help with the rest of the details if you want to dial it in a little closer. http://www.mrmalty.com/pitching.php
I think I might have put to much DME into my starter. I followed John Palmer's guide for a yeast starter, but I just tripled it. I used 3 pints of water to 1 1/2 cups DME. Should it be ok? It has been on the stir plate for almost 10 hours now. Thanks in advance.
According to the link I posted above you should be shooting for 1.030 to 1.040, you were probably double that or so depending on boil off... If you want to delay your brew day you could let this starter finish out, cold crash it, decant and try a starter at the correct gravity?
I did not take a OG reading, when should the starter finish out? When I do my next starter I should be shooting for 1600 ml of water to 160 grams of DME, correct?
That should be good. When I plugged it into this calculator it shows no real growth happening on the next starter but the yeast wont be as stressed, which means the beer should be better. Check out the link, it gives specific DME amounts once you plug everything in. You want to choose the high gravity ale option. http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/
I go with about 3/4 cup dme per liter of water (a liter is about a quart, which is two pints). This usually works out to an SG of 1.040, which is what you want. Given the example above in which 1/2 cup dme was used per pint, you about doubled what you needed. A refractometer is a handy tool cause you can take quick gravity readings while your mini-wort is boiling and boil off, or add water as you need. The small bit of wort needed for refractometer will quickly cool and give you an accurate working reading. Get one online for about $30. You will want 2quarts (2 liters, or a growler's worth) of wort for the 100B cells that you get in a smack pack or WL vial. This will roughly double your count and give you what you want for a 5-gal batch of up to a 1.070 OG ale. Higher gravity ales and/or lagers, and you'll want to step up this starter to 4 liters. Of course, to be technically correct you have to do yeast counts with a microscope and test their viability (how many are alive) with iodine. The rule of thumb will get you pretty much to where you want to be unless you introduce some wild variables with old yeast - then its either microscope it, or make sure that you do a starter, and probably a 2-step starter. In the end, the yeast is pretty flexible - you'll get beer, and probably pretty good beer. You just might get some flavor characteristics from the yeast that you may or may not like, and you won't really be able to duplicate it if you like it. I'm rambling a bit - but one last thought. I brew 2-3 batches a month and am going through a bunch of DME for starters (which aint necessarily cheap). I am going to brew 5-6 gallons of 1.040 pale wort (simply mash and boil about 10lbs of 2-row) that I am going to keg and store. When making starters, I will just draw a couple liters as needed, boil it, add nutrient, cool it, pitch yeast, stir plate. I think I will cut my cost at least in half.
There is a happy medium between actually counting/testing cells and binary if/then starter size decisions. It's Estimated Pitch Rates and there are several calculators available to determine an appropriate starter size for a given volume of a given gravity of a given type of beer (ale/lager), a given yeast package age, and a given starter type (simple/shaken/stirplate, etc.). YeastCalc and Mr. Malty are good places to start. And for those who believe the assumptions used by either of these calculators are too conservative, there are ways to manipulate the calcs to fit their own assumptions.
Yep. I agree that Mr. Malty and YeastCalc are both good tools to use. They still require some guesswork (especially if you're using harvested yeast or yeast cake). I was just offering up a workbench rule of thumb.
