Liquid yeasts are very popular, as they offer a wide range of strains with different characteristics and aromas. This enables the brewer to match the style of beer he wants to produce. Unfortunately, the population of a liquid sachet is far lower than that found in a packet of dry yeast. You’ll need to make a liquid yeast starter to give them the best possible conditions for development in the wort.
The stronger the beer, the more yeast is needed. So you’ll need to make sure there’s enough to complete fermentation before the alcohol content overwhelms the yeast.
Before you learn more about your liquid yeast starter
Always store yeast packets (liquid or dry) in a refrigerator to keep the yeast dormant and healthy until use.
The inside of Wyeast brand packets contain nutrient sachets which act as a “mini-starter”. These sachets can be broken open to release their contents into the yeast packet. The packet will then start to swell strongly, a sign of the success of the operation. However, they may not be sufficient to ensure a large enough population before inoculation. We therefore recommend a starter after activation.
But what is a liquid yeast starter ?
A starter is used to multiply the quantity of yeast before inoculation into the must, for optimal fermentation.
For 20 liters of beer, the best solution is to produce a 1-liter wort with an initial specific gravity of around 1,040. This will enable your yeasts to adapt to their new environment more easily.
We don’t recommend using sugar for this. Use malt extract instead. To make a 1-liter starter, you’ll need 100g of dry malt extract.
To make things easier for you, here’s an indicative table of the quantities of sachets you’ll need, depending on the volume of beer you’re brewing and its initial density.
What equipment is needed to make a liquid yeast starter ?
To make a yeast starter you need :
- An Erlenmeyer flask
- Malt extract
- Liquid yeast
- A magnetic starrer
- Paper aluminium
- A saucepan
All this material (except tinfoil and saucepans) is available in our pack below :
Steps to follow to make a liquid yeast starter
First of all, make sure your starter’s environment is sterile (package, scissors to open it, Erlenmeyer flask to hold yeast, etc.).
Arrange to make your starter about 3 days before your brew.
Step 1 :
If you use the Wyeast brand, pack the nutrients inside the packet the day before your starter.
For other brands, simply remove your yeast from the fridge 24 hours before your brew to keep it at a temperature of 20/25°C.
Step 2 :
As mentioned above, sterilize ALL your equipment. Yes, I know, I’m always repeating myself when it comes to hygiene !
Step 3 :
Boil just over 1L of water and 100g of malt extract in a saucepan for about 15 minutes, then pour into the Erlenmeyer flask. To avoid contamination, cover with aluminum foil.
Step 4 :
Cool the must to around 25°C and pour in your yeast. If you’re using a thermometer to measure the temperature of the must, remember to disinfect it. Place the magnetic stirring bar inside the must and cover the Erlenmeyer flask with aluminum foil.
Step 5 :
Place the Erlenmeyer flask on the magnetic stirrer and stir for a few minutes. Leave to ferment for 48 hours at 25°C, protected from light, and switch on the stirrer from time to time.
Step 6 :
Once this time has elapsed, normally the day before brewing, place your starter in the fridge to allow the yeast to settle.
Step 7 :
On brewing day, take your starter out of the fridge and let the temperature rise to 20°C.
Step 8 (the last one !) :
As this pseudo-beer isn’t very good, you’ll need to keep only the yeast. Just before inoculation, simply pour the liquid gently into the sink, taking care not to discard the yeast.
Stir the remaining yeast and you’re ready to seed your brew.
It’s true that it takes a bit of time and equipment, but there’s nothing complicated about it !