NOTE: Yeast starters are generally reserved for liquid yeast. Dry yeast are provided cheaply and in high enough numbers to just pitch multiple packs (unless you are commercial brewing).
Making a yeast starter is great way to improve your brewing product. Yeast starter as absolutely necessary when brewing with liquid cultures as there is not enough yeast to ferment 5 gallons (or more) of high gravity beer or mead.
Starters essentially build yeast to a very high number in a easy to ferment environment. In addition, they are already primed to tolerate alcohol. After which, it can plow through whatever high gravity nightmare you've created! Ferments are generally faster, cleaner, and hit higher ABV than by normal pitching. Once you experience your first starter ferment, it's difficult to go back!
2 Liter Starter for Beer
1. Add 1 tsp GoFerm to a 2 liter pyrex flask.
2. Add 650 ml water to flask.
3. Add 1/2 cup of Golden DME to flask.
4. Add one cross shaped stir bar.
5. Bring to a boil for 15 minutes with a tin foil covering.
6. Add sterile water to 1.8 liter final volume.
7. Allow to cool completely.
8. Pitch a smacked pack of yeast or yeast rehydrated in GoFerm.
9. Allow to stir on stir plate for 3 days.
10. Pitch in your mead. Don't forget that the starter will add 2 liters of volume!
2 Liter Starter for Mead
1. Sanitize 2 liter flask with cross shaped stir bar.
>To sanitize, use StarSan, OneStep, or cook it on the stove burner (let it cool before Step 2). I avoid iodine based cleaner due to staining.
2. Add 1 tsp GoFerm.
3. Add 1/2 cup honey (6 oz by weight).
4. Add sterile spring water to 1.8 liters.
5. Pitch smacked pack of yeast or rehydrated yeast
>Final volume close to 2 liters with smack pack volume added.
>I generally do break the internal packet for the nutrients, but you don't have to wait to pitch.
6. Allow to stir on stir plate for 3 days.
>Stir plate is best, but if you don't have one, just swirl it when you can and go an extra day.
7. Pitch in your mead. Don't forget that the starter will add 2 liters of volume!
For larger batches (>5 gallons), I just make a starter that is 1/10th of final volume and pitch after the yeast are obviously boiling.