Beers and ales come in all sorts of colours, from your golden lagers to dark stouts. But why exactly and what does it actually mean and say about your ale? A large part of why is the Maillard reaction, discovered by Louis Camille Maillard in 1912
So what is the Maillard reaction? It is a browning process created not by enzymes but sugars and amino acids. Different sugars and amino acids give different reactions which results in melanoidins. Without this process ales would be a completely different drink, because while alcoholic content is important it is the flavour and colour which really makes an ale. This is a very common process that you likely come across every day, it is the same reason you will see browning in cooking foods.
Melanoidins (couldn’t they have come up with a simpler word!?) come in a wide variety, with lighter malts generally creating low mass melanoidins and darker ones creating heavier ones. Depending on which are produced a huge range of flavours are achieved, from sweet to nutty to coco. The amount does help a more intense flavour but the varieties different malts make is also important. With this we can begin to see how different malts create different colours. In fact, the process begins to occur when the malt is being created. The reaction also takes place in the mash and boil.
But is there a way to take advantage of this reaction to change your homebrew? Yes, the easiest is to have a longer mash or boil time. More contact with the grain means more of what we need is absorbed for the grain, while a longer simmering boil means some more melanoidins are produced and not broken down. The amount and type of grain you use will also have an effect, though you shouldn’t always aim for the types with most melanoidins. It is about balance. There are other factors that will change the colour, hops can also have an effect but the advice above is enough to have a big effect.
The Maillard reaction is incredibly important for what makes ale the drink it is, without it we wouldn’t have the large and ever-growing variety. While you don’t need to know the exact science behind it knowing what makes your homebrew work is important.