I PAID, whisper it, £4.50 for a loaf of bread. I can already hear the derision: “Almost a fiver for one loaf? You’d never catch me doing that!” I fully appreciate that this price tag could be used as evidence that I’m a more-money-than-sense fool, duped by gastronomic con artists.

But let me tell you a little more about said loaf. It weighs around 12,000 grams; about two and half pounds in imperial measurements. It’ll keep us – two adults – in bread for a week. What’s known as a “sandwich” or “tin” loaf, it’s firm but moist, and easy to slice. No sawing required.

The crust, unlike many promising-looking, supposedly artisan creations, won’t detach from the crumb as the week goes on, nor will it become too hard to eat. The greyish-white crumb has no hidden air pockets to trap unwary bruschetta lovers.

My lovely loaf is made with organic flour; the grain was “sprouted” before milling to make it micronutrients more bioavailable. A growing body of science suggests that various nutritional and other benefits arise from sourdough fermentation: some people find that they can enjoy eating genuine sourdough bread, despite having digestive difficulty with food containing wheat or gluten proteins made in other ways.

My loaf owes its bulk to a veteran sourdough starter; no baker’s yeast, no jiggery-pokery with enzymes.

It’s keeping properties are prodigious. Stored in a Kraft paper bag it remains soft enough to eat un-toasted for a week, but it makes sublime toast too. As for the taste, well, it’s the slightly vinegary whiff midst the unusually interesting cereal presence that makes it more satisfying than an entire loaf of that cotton wool sliced stuff.

What I have on my hands here is the genuine article: a loaf that embodies the very best of modern sourdough bread-making culture. The problem, though, is differentiating loaves that fit this bill from those that look the part, and are priced accordingly, but which fall into the half-hearted, amateurish, taking advantage, or downright fraudulent categories.

I can really sympathise with people who have lashed out on what appears to be a genuine sourdough loaf and been heartily disappointed by “sourfaux” or “pseudough” offerings. What a sickener. In the context of modern baking, the motto should be “Careless talk costs loaves”. There’s no legal definition of what constitutes sourdough, and this situation begets abuse. Supermarkets sell ‘sourdough’ bread mixes that have a long list of high tech ingredients and chemical additives. Industrial bakers can even buy artificial sourdough flavouring.

But now the Real Bread Campaign has turned up the heat under bakeries – whether independent, supermarket, or chains – that cash in on the rise of sourdough. Last month it launched its Sourdough Loaf Mark scheme. Already over 50 bakeries have signed up to this annual agreement that allows them use the mark to promote bread that fits the Real Bread Campaign’s sourdough criteria: it contains only flour, water, salt, and a live sourdough starter culture.

So far, bakeries in Scotland that have adopted the sourdough loaf mark include Peter’s Yard in Edinburgh, Findhorn Bakery in Moray, and Orkney Sourdough in Kirkwall.

The Sourdough Loaf Mark is different from the Real Bread Loaf Mark. Bakeries can use that latter logo if they use only natural ingredients – everything from baker's yeast to seeds, nuts, cheese, milk, malt extract, herbs, oils, fats and dried fruits – as long as the bread contains no artificial additives, or so-called “processing aids”.

Both these bread marks are badges of honour, a guide for those of us who are prepared to pay a fair price for bread, one that reflects the work, time, and ingredients that went into the product.

Of course, proper sourdough will always cost more because the dough takes longer to rise than if made with baker’s yeast. Longer, slower fermentation allows the lactic acid bacteria in the starter to cause changes in the dough that produce bread with a glossy crust and crumb, and a greater complexity of flavour. True sourdough is skill, patience, something of a miracle. I calculate that one filling slice of my £4.50 costs me about 35p. All things considered, that’s a bargain.

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