why is guiness black?

[alex1972]

Does anybody know why guiness is so black?

[shaneystar]

Guinness is black because of the way the ingredients are prepared. Some malted barley is roasted, in a similar way to coffee beans, which is what gives Guinness the dark, ruby colour.
http://webpages.marshall.edu/~bennett7/guinness/guinqna. htm

[brachiopod]

All malted grains used for brewing are 'kilned' to stop the malting process (which is effectively germination of the barley grains).

It is the degree of kilning that affects the brew. A light kilning gives rise to 'light ales' and lagers, whilst a high degree of kilning will roast and darken the malted grains - giving rise to brews with a more full-bodied flavour and darker colour, such as in porters and stouts.