‘Dad, what happens if I get breathalysed by the police after eating Tira Misu?’ The question came from the daughter who has a provisional driving licence – a licence that requires the driver to have zero blood alcohol content whilst driving.

I thought about it for a while and said that depending on how much booze was in the dessert she ran a small but real risk of registering an alcohol blood content on a breathalyser and could therefore jeopardise her licence.

That led me to thinking about alcohol in food and the significant number of citizens who, for various reasons – religious, dietary, legal – should not consume alcohol in any form.

I knew of course that this group would avoid foods containing straight alcohol. I was reminded of the stereotyped teetotal maiden aunt who says, ‘I’ve come over all queer.’ after eating a portion of sherry trifle. Other obvious and similarly forbidden foods would include liqueur chocolates, liqueur cherries and other alcohol preserved fruits. Then there are alcoholic desserts such as the aforementioned tira misu, sherry trifle, zuppa inglese, fruit cakes ‘fed’ with whisky or brandy, brandy sauce on the plum pudding and so forth.

But I’d always assumed that cooking would burn off any added alcohol from dishes, leaving them suitable for the most pure and chaste of palate.

I was misinformed.

Now we’ve all seen celeb chefs slurping roughly measured half bottles of wine into various dishes like coq au vin. While they deglaze flaming pans with generous pours of wine or brandy and extravagantly flavour dishes with spirits and liqueurs, they’ll inevitably trot out the old myth while so doing, ‘I’m just burning off the alcohol.’ Well not quite.

When I researched the pre-eminent authority on the science of food, Harold McGee* I discovered that even food cooked for long periods will still contain around five per cent alcohol, and that ‘…briefly cooked dishes [retain] from 10 to 50%, and flambés as much as 75% [alcohol].’

I’m not saying that the retained alcohol will make you drunk. And I will accept that the small amount of alcohol you ingest from these will probably have only a negligible effect on your blood alcohol content. But, in the event you do come up before the courts for breaching a zero alcohol law you may find that de judge does not have discretion to absolve you on the simple grounds that you (inadvertently) ate the alcohol rather than drank it.

*McGee On Food & Cooking, Hardback, 884 pages. Published by Hodder & Stoughton, Great Britain, 2004. $75.