Aeneas Coffey has a lot to answer for. Although an Irishman, he must take some responsibility for the calamities suffered by Irish whiskey over several centuries, from which we are only now emerging.

Born in France to Irish parents, Coffey attended Trinity College, and in 1813 began work as sub-commissioner of Inland Excises and Taxes for the district of Drogheda. Shortly afterwards, he was promoted to Inspector General of Excise in Ireland, responsible for the collection of all duties.

In 1824, he resigned from this position and registered a patent for a new spirit still, henceforth known as the Coffey or Patent still. This new contraption made the production of spirits far easier and cheaper than ever before.

Apparently we Irish rejected this invention and continued to favour the pot still for producing whiskey. The canny Scots, on the other hand, saw its potential and began using the Coffey still to produce grain whiskey on a massive scale. This they blended with single malt to create the well-known brands that dominate the world market.

Until Coffey came along, a distiller had to fill his copper still with whatever fermented liquid (beer, wine, wash) he was using, seal it and then begin the distillation. Once finished, the pot still had to be emptied and cleaned before the process could be started once again. Coffey stills are like a huge number of pot stills piled up on top of one another, continuously distilling spirit to a higher level of proof and purity. This is the way all blended whisky, and most other spirits such as gin, vodka and brandy are made today.

Irish Single Pot Still Whiskey (the single refers to it coming from a single distillery, as with a single malt whisky) has another unique feature. Back in 1682, the government introduced a malt tax, figuring that as you need malt to produce whiskey (and beer), this would be an easy method of raising revenue.

However, the Irish came up with an ingenious revenue-avoiding solution. They realised that if they combined a proportion of malted (and therefore taxed) barley which started the fermentation process, with some unmalted (therefore tax-free) barley, they could still create a very good whiskey. So began the uniquely Irish tradition of combining malted and unmalted barley in pot still whiskey that continues today.

By the 1960s, the Irish had accepted defeat and were using the continuous still to produce the blended whiskies we know today. All of these will still contain a proportion of pot still whiskey.

At one stage Redbreast and Greenspot were the only two remaining Single Pot Still Whiskies. But as Irish whiskey begins to find its feet on the world stage once again, Irish Distillers has decided to focus on Single Pot Still Whiskey as something uniquely Irish. It is in the process of being granted Geographical Indication status by the EU and can therefore henceforth only be made in Ireland. The GI application states that a Single Pot Still Whiskey must contain a minimum of 30 per cent each of malted and unmalted barley, giving the distiller some room for creativity when making his blend.

Single Malt whisky (or whiskey) tends to be drier and more biscuity in flavour, whereas single pot still has a richer texture, described as creamy or oily, often with a light spiciness and apple or pear fruits. This is only a very rough guide, as a blender will include many whiskies of various ages from hundreds of different barrels, each originally used to mature a variety of wines and spirits, to create his final blend. It is a highly complex business requiring great skill.

Thus far, Irish Distillers has five Single Pot Still whiskies available, although other distilleries have begun the process. I was taken through the various whiskies by David McCabe, international ambassador, and Peter Morehead, production director at Irish Distillers; a fascinating exercise. I feature three today. They are not cheap, but a glass would be an ideal way to toast Saint Patrick.

As we are on things Irish, I was intrigued to receive a small bottle of wild beech leaf liqueur just before Christmas.

It is a delightful drink that worked really well as a digestif. It is made by forager, chef and guide Mary Bulfin, otherwise known as Wild Food Mary (see wildfoodmary.com), from Co Offaly. Apparently, three of Ireland’s Michelin star restaurants now serve it or use it as an ingredient in their desserts.