“If penicillin can cure those that are ill, Spanish sherry can bring the dead back to life” – Alexander Fleming.

YOU can tell it’s Christmas when Gran gets the sherry out, but beware it’s not last year’s leftovers. Too many folk are still under the misguided impression that sherry lasts forever once opened. Some of the top-end PX sherries can stay drinkable for months but in general your gran’s sherry should be consumed within four to five days, tops.

The other myth is that when sherry or wine is past its best for drinking you can cook with it or make a trifle. No, no, NO – just as you wouldn’t put a scabby carcass in the stew pot.

Sherry is one of the three classic fortified wine styles, partnered by port and Madeira, and it’s perhaps the most complicated of them all, with too many styles, dreadful labelling and too little positive advocacy. To be honest, I only like to drink two styles, the lovely lemony dry Fino and the incredible stocky Pedro Ximenez. Cream or Olorossa are good in sherry so I only buy half bottles of them, and Amontillado and Manzanilla just taste over-oxidised and faulty to me.

Fino sherry is a good all-rounder any time of the year, but looking forward to next summer you might want to surprise your beer-drinking barbecue friends with a decent ice cold Fino. Not only is it refreshing on a hot summer’s day but it’s a flexible partner with burnt burgers, over-marinated chicken and steak a la napalm. At Christmas, it’s best used as an aperitif, and perhaps as a good palate refresher before the pudding.

Pedro Ximenez is one of life’s luxuries but do yourself a favour and don’t hold back the pennies because, while a cheap, fairly thin PX can be picked up for less than £7, excellent PX can be purchased for around a tenner and world class version for above £15. PX should be dark, treacly and intensely aromatic with a finish longer than the Brexit talks, and while they can be partnered with puddings, or cheese, I find them too good to drink with anything. All you need is an armchair, a fire and a friend.

Gerard’s picks

n Hidalgo Triana PX: An incredibly rich and smooth wine with figs, treacle and Christmas cake flavours all mixed in. A lovely sipping sherry but you can also serve it as an ice cream sauce if you want to be a wee bit decadent. Richardson’s of Whitehaven, £16.99.

n Exquisite Fino Sherry: Dry, nutty and very refreshing. Aldi describe this as slightly salty, but I didn’t get that, although I did get a lovely mouthful of nutty flavours and a crisp lemon finish. Delicious, superb in fact for the price. Aldi, £5.99