It is considered best practice to rehydrate all dry yeast rather than pitching directly into a mead must (see for example the BJCP Mead Exam Study Guide). Another method not mentioned in the BJCP Study Guide* is an activated starter. This involves rehydrating yeast with a rehydration nutrient and step feeding with must and waiting until the yeast has been able to absorb the rehydration nutrients. This differs from a traditional starter in that the intent is not to grow the yeast population, but to encourage healthy rehydration and preparation for the must. An activated starter is the first step in making mead and should be ready as soon as the full mead must is prepared.
Activated starters are considered best practice, and used by many award-winning mead makers. An activation starter can improve yeast count and viability to encourage a stronger and cleaner fermentation. See variants of the method mentioned on Mead Made Right, Mead Makr Batch Buildr, and known to be used by Ken Schramm. As stated in the Scott Labs Handbook 2017: “Proper yeast rehydration is one of the most important steps to help ensure a strong and healthy fermentation.” Alternatively if the micro-nutrients were merely added to the must “competitive microorganisms would use a significant amount of them and others would be chelated by polyphenols” (Scott Labs Handbook 2017, pg 40).
The advantages can be summarized as follows:
- proper rehydration increases yeast cell count
- proper rehydration nutrient reduces osmotic stress to improve yeast health
- gradual tempering the temperature reduces shock stress at pitch
- gradual tempering the starter gravity reduces osmotic shock stress at pitch
- allows time (about three hours) for the yeast to absorb the rehydration nutrients in a less-stressful, less-competitive environment
What you will need
- Appropriate amount of rehydration nutrient (recommended amount of Go-Ferm or Go-ferm Protect is 1.25x the weight of dry yeast)
- 2x Jars – one for the honey must and another for the yeast activation starter (Try to get the widest jar possible for rehydration to maximize surface area)
- Clean, chlorine free, water at 110°F (44°C). 20 ml per gram of Go-Ferm (125 ml total for a 5 gram packet of dry yeast, and 6.25 g of Go-Ferm).
- Honey – enough bring the starter close to full must gravity
The size of the activated starter depends on the mead that you’re making, approximately 300-600ml per 5 grams of yeast is a good start.
10 Easy Steps to make a Mead Yeast Activation Starter
- Let your dry yeast come to room temperature before rehydrating
- Sterilize everything you are going to use everywhere
- Dissolve Go-Ferm (or Go-Ferm Protect) in your clean, chlorine free, water at 110°F (44°C). Use a thermometer.
- Wait for the temperature to come to yeast pitching temperature, 104°F (40°C) for most wine yeasts or lower for ale yeasts.
- Gently sprinkle the packet of yeast evenly over the solution. Swirl/stir gently only if any dry yeast clumps.
- Prepare the starter must (200-400 ml per 5 grams of dry yeast) at the desired must gravity, shaking aggressively to aerate and mix honey and water.
- After 20 minutes from sprinkling yeast, gently swirl/stir the solution to submerge any remaining dry yeast.
- After 5 more minutes (and definitely before 30 minutes from sprinkling yeast), spoon in a small amount (1/4 cup, ~59ml, for 5 grams of yeast) of starter must to the yeast slurry. Do not allow the temperature drop exceed 18°F (10°C). Atemperation steps below 10°F are prudent.
- Keep adding the same amount of starter must (1/4 cup, ~59ml, for 5 gram packet) every time yeast activity picks up, every 15–20 minutes or so, until all the starter must is used. Again, do not allow the temperature drop exceed 18°F (10°C).
- Now make your full mead must, so that after at least three hours you can pitch your activated yeast starter into fermentor as soon as the full must is mixed. The activated yeast starter should be as close a possible to the temperature of the must. If the must is below 55°F, the starter should be within 5°F before pitching.
Go-Ferm dissolves better the warmer the water. An alternative to step 3 is dissolve the Go-ferm in near boiling water, 1/3-1/2 the total amount of water needed. Once dissolved, use the remaining water at room temperature to bring the temperature of the slurry as close to rehydration temperature. This saves time waiting for Go-Ferm to dissolve and arrive at rehydration temperature.
The recommended dosage rate is 1.25 grams of GO-Ferm per gram of yeast. However, Go-Ferm contains vitamins, minerals and amino acids. Over use of GO-FERM with other organic nutrients such as Fermaid-O/Fermaid-K can lead to unami (think wet dog food) or brine flavors. See TANG nutrient regime for more details on avoiding this.
Have your activated starter ready to pitch as soon as the full mead must is prepared. This helps give your yeast a head start over indigenous organisms. This is especially true for yeast with a low competitiveness factor. For this reason, winemakers are advised to “add the yeast slurry to the bottom of the fermentation vessel just as you begin filling the vessel with must/juice” (Scott Labs Handbook, 2017 pg 7).
Never use distilled (or reverse osmosis) water if you are not using Go-Ferm. In this case, it is best to use harder water of approximately 250-500 ppm. In fact, if you are not using Go-Ferm, the steps are different and this article does not apply to you.
Scott Labs Handbook 2017, Scott Labs, http://www.scottlab.com/pdf/ScottlabsHandbook2017.pdf
* The BJCP does recommend using a variant of the above described method, but only for restarting stuck fermentation.