An Infusion Mash is a procedure which is popular amongst home brewers. Herein, all grains are placed in the tun and then added to the brewing liquor. Prior to being added to the grains, the brewing liquor is heated to what is known as the “strike temperature”. The strike temperature is hotter than the sought after temperature for enzymatic activity. The liquor is heated in order to balance the fact that the grains are cooler than the sought after temperature.
Next, the mash is placed in a lauter-tun. The grains are washed with hotter water to extract all the sugars from the tun; this process is called sparging. This process stops any more potential enzymatic activity should much hotter water be used. The mash can be heated to 80°C to stop any such activity before placing it in the lauter-tun. This also prevents cooler grain from reducing the sparge water temperature to a temperature lower than desired.
The resultant wort is boiled for about an hour and a half. Copper hops are added in towards the start of the boil, as well as flavouring hops after 75 minutes.
Irish Moss, a kind of seaweed, is usually added at the end of the boil, in order to eliminate the possibility of any hazes in the final brew.