Christine Jardine: Why do we have a beef with eating horses?

But this year the timing could be a little better. There has been something almost surreal about the public debate around the discovery of traces of horse and pig in some burgers sold in a selection of supermarkets.

First there was the fact that something we normally call pork, ham or gammon we started to call “pig meat”, as if somehow it was different from what many of us regularly consume.

Then there was the fact that we could be surprised that something called a “value burger” could be anything other than stuffed to the gunnels with the highest-quality beef.

There was even a sudden explosion of Facebook and Twitter comics with an endless supply of Shergar jokes.

But perhaps the most surprising aspect was the sudden, almost embarrassed realisation that perhaps we might be employing double standards over so much of what we eat.

At a dinner with friends, surrounded by a table of meat eaters, the main questions at the heart of our conversation seemed to be: “How ridiculous do we all sound?” and “How do we decide which animals are acceptable to eat and which are not?”

Let’s be clear: there was absolute agreement that it’s not acceptable for something – anything – to get into our food that we do not know is there.

Similarly, we all sympathised with those with a religious belief that prohibits eating certain types of meat who could have broken those rules without knowing and through no fault of their own.

In answer to how we can be sure what we are eating, we all suggested using a butcher you know and trust, or buying only fresh clearly labelled meat from the supermarket.

But on the question: “Why is it all right to eat some animals and not others?” we were stumped.

We couldn’t say what it is about horses and dogs which sets them apart from cows, pigs, sheep, lambs, rabbits, chickens, geese, ducks, deer and all sorts of fish – at least in this country.

In other cultures there is no issue, and not just with horses. During a trip to South Africa I watched, amused, as my husband innocently asked what was in the crocodile salad, thinking that like “Waldorf” it was just a name.

It took several attempts by the waiter to convince him that it was, in fact, crocodile he had enjoyed.

There were other unusual animals to eat on that trip where we were told the local attitude was that if it can be hunted it can be eaten.

I don’t know that I agree, but at least it’s a principle I can understand, unlike in this country where the best I can discern from the public discussions over the past week is that we have an ill-defined, rather fluffy notion about animals that are domestic: that somehow some animals which qualify as pets are actually “friends”.

Even then that doesn’t allow for chickens, ducks and rabbits, which can be pet-like and have names but also be eaten.

The final and most absurd contradiction of all is the one about the conditions our foodstuffs live in.

Amongst my friends there is agreement that we like to know our animals are well looked after, cared for even, before they are slaughtered.

Many of us have no stomach for what we perceive as the cruelty of factory farming of the animals we eat.

It’s a strange notion that somehow our conscience absolves us of any guilt we might feel for consuming them: at least they had a good life.

It’s possibly the same train of thought that teaches us as children that cows give us milk and we get wool from sheep. No mention of beef or lamb.

When you think about it – the double standards and ridiculous post-facto justifications – you begin to understand why so many people have turned away completely from eating meat. That’s an argument that at least makes sense.

Since the end of the Second World War, a vegetarian diet has become increasingly popular. According to the Food Standards Agency’s Public Attitudes to Food survey in 2009, 3 per cent of those who responded were completely vegetarian. Another 5 per cent chose not to eat some types of meat and fish. There have been other surveys that suggest figures closer to 10 per cent, and the Vegetarian Society reckons there are between three and four million vegetarians in the UK.

On its website it defines those three to four million people as those who live “on a diet of grains, pulses, nuts, seeds, vegetables and fruits with, or without, the use of dairy products and eggs. A vegetarian does not eat any meat, poultry, game, fish, shellfish or by-products of slaughter.”

But there is also another group increasingly labelled as “meat avoiders”.

By that they mean those consumers who are cutting down on their meat intake for health or climate change reasons, or who simply enjoy having a wide variety of foodstuffs in their diet.

That health argument begins to approach an explanation of why we eat some animals and not others. After all, we know that some, such as deer, are leaner than others.

But it’s still not a complete answer.

When you get to the heart of it, there doesn’t seem to be a real, coherent argument about why we eat some meat and not others. It’s all about personal choice.

And just when you think you’ve thought of everything, you remember it is January and there is a haggis waiting in the fridge.