Apologies in advance for disturbing the cordiality of the festive season - but do beware the ingredients in your shop-bought Christmas cake.

Not just those tooth-cracking, ‘edible’ silver ball decorations, but the long list of weird and distinctly un-wonderful ingredients that turn up in yuletide cakes, puddings and pies. I’m talking delights such as ‘gluten-free breadcrumbs’, with their secondary ingredients of water, potato starch, maize, vegetable oil, guar gum, methylcellulose, salt - and a dash of mono- and diglycerides of fatty acids.

Anything with dried fruits is a haven for synthetic flavourings, colourings, preservatives, shelf life-extending humectants and various forms of glucose-fructose sugar, an ingredient increasingly linked to the obesity epidemic in the US.

Fruits are usually described as ‘mixed vine’ - code for the cheapest, most anonymous products. You’ll have to hunt down nuts. As they are pricey, manufacturers are truly stingy with them and keep their use to a minimum.

You’ll struggle to find a pie, cake or pudding made with freshly shelled eggs - let alone liquid ones. It’ll be pasteurised egg if you’re lucky, a substance called ‘dried egg albumen’ if you’re not.

Even Heston uses dried egg in his mincemeat pies. Be sure to go for ‘all-butter’ items, otherwise you’ll be chomping your way through margarine and vegetarian suet made with rapeseed and rainforest-depleting palm oil. Ethical ingredients go out the window at Christmas; anyone after Fairtrade nuts will have to head to Oxfam.

I have often wondered why shop-bought Christmas off erings never taste quite right. For an explanation, look no further than the ingredients you’d never use at home - such as citric acid and lemon juice ‘from concentrate’.

Having flirted with the idea of buying in rather than making my own, the sobering list of ingredients re-motivated me.

My homemade pudding - with organic raisins, sultanas, and home-made candied orange peel, plump Agen prunes, a decent amount of pecans, freshly-cracked organic eggs, freshly-squeezed orange juice, grated windfall apple, freshly-ground spices, sourdough breadcrumbs and lashings of Somerset apple brandy - looks and smells fantastic. Call it cocky, but I’m cautiously confident that it will taste a whole lot better than anything I could buy.