St Patrick's Day 2014: Why is Guinness black - and other mysteries surrounding Ireland's favourite drink

No beer commands such mysticism as Guinness, with many questions, interesting facts and popular misconceptions surrounding the black stuff.

First produced by the brewery of Arthur Guinness in Dublin in 1759, it has become synonymous with Ireland, as well as a global brand - the stout beer is brewed in near 60 countries and sold in over 100.

So do the ingredients in Guinness make it the best thing to survive on if you are stranded on a desert island? - Here are some of the most common queries answered...

1. Why is it black?

Guinness is black - or dark ruby red as the company claims - because of how it is brewed. Guinness is a stout beer meaning it is created using roasted malted barley, in a similar way to how coffee beans are prepared. The intense heating process cooks sugars, amino acids and grains together to produce very dark colours.

2. Why is it not vegetarian/vegan?

Guinness isn’t vegetarian/vegan as it can contain trace amounts of fish bladder. Isinglass, a form of collagen pulled from dried fish is used in the fining process - the removal of unwanted particles such as degenerated yeast cells left over after the beer has been brewed.

3. Which is the world's biggest consumer of Guinness?

Not Ireland - it's Nigeria that takes the crown. In fact, 40 per cent of Guinness consumed worldwide is drunk in Africa, while three of the five Guinness-owned breweries globally are on the continent. The first to be built outside Ireland and Britain was in Lagos in 1963. The black stuff is also particularly popular in Cameroon and Ghana.

In some African countries, you can also get a super strong variant - Guinness Foreign Extra Stout. A bitter finish and 50% stronger, it has been adapted to suit local tastes.

4. Where does the white head come from?

The creamy white head is created by nitrogen and carbon dioxide gas that is passed through the beer as it is poured through the pump.

5. Why is it poured in two parts?

Guinness is poured in a two parts in order to enable the pint to have the right amount of head. Three quarters of the pint is poured at a 45 degree angle, the surge allowed to completely settle, before the last quarter is added at a 180 degree angle.

6. Why does Guinness taste better in Ireland?

Well, although the Irish charm is likely to add to the wider experience, technically it doesn’t. While the Guinness popular in Africa is a different mix, that consumed in the UK and US is exactly the same as that in Ireland - it is even made in Dublin at the historic St. James's Gate Brewery.

7. Is it good for you?

The old Guinness ads carried the slogan ‘Guinness is good for you’ and there are plenty of rumours floating around that you could survive on only Guinness due to its high energy content. Afraid that isn’t the case - at 210 calories a pint, Guinness isn’t even that calorific. Neither is it that good a source of iron - three pints contains the same amount as a single egg yolk.

It’s not all bad though - researchers have found that a pint may work as well as a low dose of aspirin to prevent blood clots.