NBA LABEL
FERMENTATION

In the brewery, the sugar source is the hopped wort together with any liquid sugars required. The wort has also been cooled and aerated on the way to the fermenting vessel, and is ready for yeast to turn it into beer!.

Pitching

The yeast is now "pitched", usually by injecting the correct quantity, in slurried form, into the cooled aerated wort stream on its way to the fermenting vessel.
The yeast we use is a carefully selected strain which is kept in special cultures in the laboratory. These are grown up in batches of increasing size until there is sufficient to pitch an entire brew. Since the yeast multiplies during the fermentation, we use only the freshest to pitch the next fermentation.

Declaring The Brew

As soon as all the wort is collected in the fermenting vessel, it is cut to the required gravity. It is then "roused" with air to mix the cutting liquor into the wort.
The gravity is checked by the brewer, and the vessel is "dipped" to measure the volume to be declared to HM Customs and Excise. Original gravity and dip must now be entered or "declared", immediately into the excise book.
In some breweries collection and declaration of wort take place in a separate collecting vessel. The brew is later transferred to the fermenting vessel.

Now Fermentation Gets Going

Once the yeast is pitched, there is a short delay while the yeast adjusts to its new surroundings. It soon sets about growing and multiplying to produce more yeast. As it does so, it uses up the sugars as a food source and produces alcohol and carbon dioxide. To the yeast, of course, these are waste products!.
Some of the carbon dioxide gas dissolves in the beer to give it the characteristic fizz, but large quantities are allowed to escape from the fermenter and must be vented away safely.
Safety procedures must always be observed and gases such as treated with respect. High levels of carbon dioxide can be quickly fatal.

Fermentation is a process which gives out energy and this causes the temperature to rise. If this isn't controlled, the yeast can be damaged and the beer flavour ruined. The heat given out by fermentation is removed by passing a liquid coolant through a jacket over the outside of the fermenting vessel.
The progress of the fermentation is controlled by adjusting the temperature. As you might expect, the fermentation goes slower if it's cooler. Fermentation can take anything from thirty to one hundred and eighty hours depending on the type of beer we are making, the original gravity of the wort, and the temperature.

Cooling Back

The brewer uses his skill and experience to adjust the temperature so that the fermentation slows as it reaches the correct final gravity. Fermentation is then stopped by cooling the vessel right down to a temperature at which the yeast settles out. FORWARD




The Brewing Process
[Console] [Yeast] [Malting] [Milling] [Mashing] [Cereal Cooker] [Mash Mixer] [Lauter Tun] [Copper] [Whirlpool] [Wort Cooler] [Fermentation] [Maturation]



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