Hops give the bitterness to balance the malt’s sweetness. They are also a preservative. There are numerous types of hops.
The following are great for real ales:
- Goldings: Fantastic flavour, however, with less bitter than certain other varieties.
- Fuggles: The flavour is on par with the golding, however, less bitter than other varieties.
- Challenger: This is fairly modern hop, however, it has a great flavour and is quite bitter.
The bitterness of hops varies between varieties. The bitterness also depends on growing conditions. Reliable home brew suppliers offer hops with the % Alpha Acid (a measure of the hops bitterness) on the pack. It is best not to use hops which do not have this information on the pack.
A straightforward formula that can be used to calculate the amount of hops needed is as follows:
Hops (g) = (Bittering Units Required x 25) / (% Alpha Acid x 2)
For stock bitter, it is best to work with 20-25 bittering units.
An extract brewer is able to use any kind of hops. Once the wort is on the boil, the hops are added to it. They are then boiled for 90 minutes to extract the flavour and bitterness of the hops.
Certain home brewing recipes ask for hops to be added some way through the boil, especially for the last 15-20 minutes. They are called late copper hops, being added to replenish the hop flavour lost during the boil.
Hops may also be added after the boil. You can steep them in the hot wort for around 30 minutes; they help restore aroma lost during the boil. This process is known as dry hopping.
A further dry hopping technique for restoring hop aroma is to add hops to the cask.