June 3, 2017 – Making a Yeast Starter
There’s a popular saying in the homebrewing world: “Brewers don’t make beer. Brewers make wort and yeast makes beer.” With yeast playing such a large role in the brewing world it’s imperative we do everything we can to keep them happy and stress free. One way to help with this is by making a starter two to three days before brewing. There are many benefits to making a starter, namely higher cell count at pitching, lower lag time, less chance of the batch getting infected, and it’s a great way to increase cell count for high gravity beers or batches that are larger than 5 gallons. Not all yeast needs a starter beforehand; packets of dry yeast and Imperial Organic Yeast both start with higher than average cell counts, which makes them “pitch-ready.” To make a starter you will need:
- Erlenmeyer flask or growler
- Dry malt extract
- Water
- Yeast Nutrient
- Aluminum foil
- Stir plate (not necessary, but recommended)
A starter is essentially a mini beer made to about 1.040 starting gravity. 1.040 tends to be kind of a sweet spot for yeast cell production. If you go too high above this the yeast can start to produce too much alcohol which can cause stress and lead to off flavors. Too low and the yeast won’t create enough daughter cells, thus limiting the effectiveness of the starter.
When making a starter you’ll first want to take your yeast out of the fridge and bring it up to room temperature. This will usually take between three to six hours. Your starter wort will be a ratio of 10 milliliters of water per gram of DME. So, for a two-liter starter you’ll use 200 grams of DME and two liters of water. If you don’t have a scale that can measure grams this would be equivalent to 2 cups of DME per half gallon of water. Mix the water and DME in a stainless-steel kettle, add 1/8th of a teaspoon of yeast nutrient, and bring to a boil. Boil for 15 minutes, then remove from heat, cover (be sure to sanitize your lid), and chill in an ice bath.
Once the starter wort reaches a temperature between 65°-75°F you can go ahead and transfer the wort to a sanitized fermentation vessel; an Erlenmeyer flask works well. Pitch your yeast and cover the container with a piece of sanitized aluminum foil. Set your starter out on the counter, somewhere easy to see. Every time you walk past it give it a good swirl. The goal is to get as much oxygen dissolved into solution as possible. Once the yeast is done fermenting (or even if it isn’t) you can pour your starter directly into your batch of wort, there’s no need to drain off any of the liquid.
As always, Brew Your Own Brew is here to help with any questions our customers may have. Feel free to call, email, or fax (if you still have a fax machine), any of our three stores.