After the starch has been converted into sugar, it needs to be extracted from the barley. This is done by passing the malt through a milling machine which coarsely grinds it into a type of rough flour called grist, using a series of giant rollers. The first roller bursts the grain open and the subsequent ones grind the grist into a suitable consistency. Our mill is a 4-roller malt mill made by Alan Ruddock Precision Engineering. This grist is not as fine as flour and still contains all the elements of the husk. It is judged on three components: the husk, the grit (or middle) and the flour. The grist must be of the right consistency for mashing, so as to allow all the sugars to be absorbed by hot water while at the same time not allowing the water to simply run through. After milling, our grist is stored in a small hopper which has enough capacity for a single production run. When the hopper is full, a sensor signals for the grist to be moved to the next part of the process.