Can your fermentation be improved?

Here is some simple advice on how to easily achieve better fermentation and clarity:

Add oxygen to your herb
nourishment in your herb
Possibly clearing
prepare the yeast
correct fermentation temperature
diacetyl pause
Cooling clearance

Yeast cells seen under a microscope

When yeast is added to the wort, it enters an aerobic phase where it uses oxygen to reproduce. Once the oxygen is depleted, it begins to ferment. It is therefore important to have sufficient oxygen present for the yeast to reproduce healthily and get to work.

The optimal oxygen level is 8 – 10 ppm dissolved oxygen. If you let the wort ’splash’ down into the yeast bucket, you will achieve 2 – 3 ppm.

How is oxygen then practically added for home brewers? – with a small pump via a sterile filter, silicone hose and oxygen stone. Here, 8 ppm is absorbed at 22 degrees Celsius warm wort. The lower the temperature, the more oxygen is absorbed. At 27 degrees, only 7 ppm is absorbed.

2: Furthermore, yeast needs minerals and salts to work optimally. It is recommended to use Servomyces, a product made from yeast cells with added zinc, among other things, and recommended by WhiteLabs, etc.

If you want a clear beer, you can advantageously use Klar Urt, a product based on carrageenan (extracted from Irish Moss).

4: Yeast is found in 2 forms: liquid and dried.

Liquid yeast is typically found in packets with enough cells for 20 – 25 litres and can advantageously be propagated if it is a little old, or needs to be used for more than 25 litres.

The dried yeast should be hydrated before use with clean water, as it easily penetrates the cell wall and ’wakes up’ the yeast. Do not sprinkle the dried yeast directly into the wort, as the higher viscosity of the wort makes it harder to penetrate the cell wall.

Hydrating dry yeast:

- for 11 grams of yeast, use 1.2 dl of water which is boiled and cooled to approx. 25 degrees.

The yeast is added and must stand for a minimum of 15 minutes before stirring and further addition.

5: It is important that the yeast works within the temperature range for which it is specified. The warmer the yeast works, the more esters (spice, fruit, and floral flavours) are produced.

6: When fermentation is complete, i.e. the specific gravity no longer drops, it should stand still for 4–5 days to allow the yeast to clean up after itself. This is also called a diacetyl rest.

7: If possible, the beer can be cold-conditioned. You should place the yeast tank as close to 0 degrees as possible for 5-7 days.

This is a very concise version of the entire fermentation issue, and one can delve much deeper into the subject, but if you use the information above, you've come a long way.

Lund Teknik can, of course, assist with the equipment and raw materials mentioned, for example:

Air pump with steril filter, silicone tubing and aeration stones

Liquid yeast and dry yeast

Servomyces Mix, Clear Herb and the easy solution; Clarified Wort and Servomyces in pack for 25 Litre Home brew.