LITMIR.BIZ

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it is worth asking what the makers of bread with added enzymes are actually trying to achieve: a saleable product or good food? Enzymes are used not for any nutritional benefit to the consumer, but to make it easier to produce bread on an industrial scale, to maximise loaf volume, to soften crumb texture and to maintain that softness for as long as possible. The net result is often a loaf of degraded nutritive value.

      So there it is: your standard British loaf, made with all sorts of things you didn’t know were in it. Do people increasingly find modern bread not to their taste because of all these additives and ‘processing aids’? Perhaps. But the changes in bread since the 1960s go deeper. They affect almost every aspect of how it is made. Each change may have had its own logic at the time but together they have left us with bread that may be fundamentally flawed.

      How our bread has changed

      The great achievement of modern industrial baking was to make a superficially attractive loaf using a high proportion of home-grown wheat. This provided a market for British cereal farmers and saved the bakers the tariffs on imported – mostly Canadian – flour. But to turn British wheat into the kind of bread that most people appeared to want, new methods were required:

       Wheat hybrids were bred to take advantage of intensive chemical agriculture and to produce flour that suited industrial baking methods.

       Millers separated the whole wheat more completely into its constituent parts, ground the flour finer and added enzymes to make it more consistent.

       To make the dough rise quickly, bakers massively increased the amount of yeast.

       Time was squeezed out of the baking process, and with it not just flavour but vital nutritional benefits.

       Freshness was redefined and artificially induced by means of additives, some undeclared.

      A technological and commercial triumph turned out to be a nutritional own-goal.

      Wheat

      At the end of the Second World War, explosives manufacturers experienced a distinct decline in sales. If not exactly beating bombs into ploughshares, they found a ready outlet for their chemicals in the intensive agriculture that was seen as the only way to feed rapidly growing urban populations. Grain varieties were bred to respond to heavy applications of soluble nitrogen, potash and phosphorus fertilisers. But such a regime produces flabby straw that falls over in wind or rain. So wheats with short straw were developed.

      Once hooked on soluble chemicals, the new varieties showed signs of succumbing more than before to fungal and pest attack. So new strains were bred for built-in resistance. Shorter stem length means less canopy to suppress weeds, meaning the new varieties also had to be able to thrive in the presence of herbicides. The millers wanted their say, too, so the breeding programme was tweaked to produce wheats with proteins more suitable for bread baking. And each year, yields had to go on rising.

      Yield, short straw, disease resistance, milling quality – the plant breeders have obliged. They have done so, to date, without recourse to GM technology, though that is in the wings.

      What is striking in all of this – for those of us who think that farming has something to do with feeding people to keep them in good health – is that nutritional quality doesn’t get a look in. No one seems to have asked whether, as variety succeeded variety with bewildering speed, wheat was getting better or worse to eat, more or less nutritious, more or less digestible. The most sophisticated science is used to analyse ‘quality’ differences between contenders for the UK National List of cereal varieties subject to Plant Breeders’ Rights. Yet, cereal scientists, along with the big millers and bakers, act as though, nutritionally, all wheat varieties are much the same. Advances in the purely functional properties of wheat have come at the price of reductions in its nutritional quality. The precursors of modern bread wheats – einkorn, emmer and spelt – all contain more nutrients than their commercial successors. Research at the International Maize and Wheat Improvement Center in Mexico revealed that the best traditional wheat varieties had about twice the iron and zinc of popular modern varieties, and their wild relatives had another half as much again⁷. In Europe, the French National Institute for Agricultural Research has shown that the mineral content of current French wheats is 30-40 per cent below that of older varieties⁸.

      Milling methods

      Before the invention of roller milling, all flour was produced by crushing wheat between revolving stones. All parts of the wheat – bran, germ and starchy endosperm – were pulverised and mixed together into what we know as wholemeal, or whole wheat, flour. If you wanted whiter flour, you had to sift the wholemeal through wire sieves or ‘bolting cloths’ made from cotton, linen or silk. The roller-milling system, deployed from 1870 onwards, was quite different. It passed the wheat between pairs of steel cylinders, which gradually stripped the layers off the grain, sifting the material thus produced into a series of streams, each containing a different fraction of the flour. These could be taken off and bagged separately or recombined to make ‘patent’ flours for various baking purposes.

      Wholemeal flour is, in theory, the entire wheat grain (minus its husk) ground into flour. In British parlance, this is flour with a 100 per cent ‘extraction rate’: 100 per cent of the available flour or meal has been ‘extracted’ from the grain. White flour has only approximately 72 per cent of the content of the wheat, the remaining 28 per cent consisting of the bran layers on the outside of the grain and the germ tucked in one end. What used to be called ‘wheatmeal’ was about 85 per cent extraction. ‘Brown’ is a generic term describing flour of about 80 per cent extraction. Most of the vitamins and minerals are in the outer bran layers of wheat. In white flour milling, these are mostly sold for animal feed.

      Wheat sold as breadmaking flour is more valuable in monetary terms to the miller than the residues that go to the animals. When it comes to nutritional value, however, the reverse is true. The table below shows what happens when whole wheat is milled to white flour⁹:

       Vitamin and mineral loss during the refining of whole wheat to 70 per cent extraction white flour

      The only word to describe bread made with such flour is ‘depleted’.

      Whereas stone milling and sieving/bolting had generally produced a white flour consisting of 75-80 per cent of the original wheat, roller milling reduced this to 70-73 per cent. The visible effect was to produce a whiter flour with fewer flecks of bran in it. Far more important, however, was the reduction in the roller-milled flour of several important nutrients, including calcium, iron and B vitamins, which the stones had formerly dispersed throughout the flour. Removing the germ, which contains virtually all the valuable vitamin E of the wheat, was a nutritional disaster but a great benefit to the millers. The wheat germ oil tended to oxidise and go rancid within a few weeks. Without it, white flour could last for several months – exactly what was needed as milling companies became larger, with ever-longer distribution chains along the country’s fast-expanding network of railways and roads. Not for the last time, nutritional integrity was a casualty of the commercial need for ‘shelf life’. Some of the vitamin E, incidentally, goes to the supplement industry, which is happy to sell it back to us in capsules at many times what it might have cost us if we simply ate bread made with stoneground wholemeal flour.

      In a French study in 2005, stoneground organic flour was shown to have 50 per cent more magnesium and 46 per cent more zinc than roller-milled non-organic flour¹⁰. This effect, it should be explained, was observed not in wholemeal but in flour milled to a finer extraction rate of around 80-85 per cent. Many people consume too little magnesium and the role of zinc in good health is well established. It would not be unreasonable

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