Intro to Brewing

Question 1

Define the term beer

Answer 1

an alcoholic beverage, produced by the fermentation of sugars derived from malted cereals, and flavoured with hops

Question 2

The beer types by their fermentation method

Answer 2

Lagers, Ales, mixed fermentation

Question 3

Lagers

Answer 3

These are beers fermented with the yeast Saccharomyces pastorianus that were traditionally fermented at lower temperatures than ales (9-15°C)

Question 4

Ales

Answer 4

These are beers fermented with the yeast Saccharomyces cerevisiae, historically fermented at warmer temperatures than lagers (15-25°C) with more body on taste and often richer in flavour and colour

Question 5

Mixed fermentation beers

Answer 5

These are beers fermented at ambient temperatures (around 20°C) by yeast and bacteria. They often have elaborate methods of production including aging in barrels and the addition of fruit.

Question 6

How we classify modern beers into styles

Answer 6

Each style of beer belonging to a particular family will have a set of attributes that set it apart from the other styles in that family.

Question 7

The main steps in the brewing process

Answer 7

Milling, mashing, wort separation, boiling, wort clarification, wort cooling/oxygenation, fermentation, cask wracking, maturation, filtration, packaging

Question 8

Milling

Answer 8

In milling, we take the whole grains of malted barley (and sometimes other cereals) and crush them ready for the next stage. This breaks open the grain, giving access to the starch (our source of fermentable sugars) inside. We refer to the crushed grain as grist.

Question 9

Mashing

Answer 9

In mashing, we mix the grist with hot water and leave it to stand for a period. In the mash, the grain’s starch and protein are broken down into sugar and nutrients for the yeast. They dissolve in the water to make a sweet liquid called wort.

Question 10

Work seperation

Answer 10

In wort separation, we collect the wort, separating it from the insoluble parts of the grain (spent grains). We rinse the grains with hot water to help extract as much of the sugar and nutrients as possible. This is called sparging. We can then use the spent grains in different ways, e.g. as animal feed, in composting, or in energy generation.

Question 11

Work boiling

Answer 11

In wort boiling, we boil the wort vigorously in a vessel called the wort kettle. The boil sterilises the wort and improves its flavour, amongst other things. We add hops to the boiling wort in order to add bitterness, aroma, and flavour to the beer.

Question 12

Work clarification

Answer 12

After the wort is boiled, we clarify it by removing the spent hops and other solid material produced in the boil. These materials have the same fate as the spent grains.

Question 13

Work cooling/ oxygenation

Answer 13

Next, we chill the wort down to the correct temperature needed for the yeast to start the fermentation. Some types of yeast need oxygen before they ferment; we can thus also add air or oxygen at this stage.

Question 14

Fermentation

Answer 14

During fermentation, the yeast transforms wort into beer by converting sugars into alcohol and making the compounds that give beer its characteristic flavour. At the end of fermentation, we cool the beer down, which helps the yeast to settle out of the beer.

Question 15

Cask racking

Answer 15

With some cask beer, we fill (rack) casks with the beer at the end of fermentation. The beer racked into the cask contains live yeast cells and matures in the cask.

Question 16

Maturation

Answer 16

In cold maturation, the beer is cooled down again and held at this temperature for a specified length of time. We mature the beer to improve its flavour and make it easier to filter. We package unfiltered beers after the maturation step.

Question 17

Filtration

Answer 17

In filtration, we remove any yeast that has not settled out naturally, along with any hazes that have formed in the beer during maturation. The beer leaving the filter is referred to as bright beer. Some beers are filtered so finely that most microbes are removed. This is called sterile filtration. The beer in the bright beer tank has the same characteristics as you would drink from the bottle, can, or keg.

Question 18

Packaging

Answer 18

The beer from the bright beer tank is filled by very clever equipment into either kegs, bottles, or cans. Beer that has not been sterile filtered is sometimes heated to kill most of the microbes in the beer. This process is called pasteurisation.

Question 19

Draw a simple flow diagram of the beer production process

Answer 19

See online