Friday, August 15, 2014

How new brewing methods gave us white bread

Our daily foods don't only give us energy and nutrients. They also embody a lot of societies developments. White bread is not only a product of personal choice. The article  below is from my forthcoming book, Global Eating Disorder. 

The earliest cultivated forms of wheat were einkorn and emmer wheats, first cultivated some 10,000 years ago in the south-eastern part of Turkey. Bread wheat developed some one thousand years later. Two very important properties of the wheat plant had to be manipulated to adapt it to farming. First it was necessary to stop the shattering of the ear (also called head or spike) at maturity, which resulted in seed loss at harvesting. Second there was a need to change from hulled forms to forms where the chaff (casing) didn’t stick to the grain in order to allow the processing of the wheat into porridge or bread. Wheat spread via Iran into central Asia, reaching China by about 5,000 years ago and to Africa, initially via Egypt. And it reached most parts of Europe some 5,000 years ago. It was introduced by the Spaniards to Mexico in 1529 and by the British to Australia in 1788. Most wheat grown worldwide is bread wheat, and most of the remaining 5% is durum wheat, which is better adapted to the dry Mediterranean climate than bread wheat and is often called pasta wheat to reflect its major end-use (it is also used for regional foods such as couscous and bulgur). In the 10,000 years it has existed, more than 25,000 types and varieties of wheat have adapted the crop to a wide range of environments. If there is sufficient water and mineral nutrients available and pests and pathogens are controlled, yields can exceed 10 tonnes per ha. But the global average yield stands at less than 3 tonnes per ha.[i]

Wheat can be stored for many years without losing much of its nutritional value,[ii] even if the often repeated story of 3,000 old wheat seeds from a Pharaonic grave germinating is a just a smart marketing myth. Another blessing of wheat, compared to other grains, is that doughs formed from wheat flour allow us to make a wide range of breads and other baked products (including cakes and biscuits), pasta and noodles, and other processed foods. A ship biscuit from 1852, purportedly the oldest existing in the world, is displayed prominently at the maritime museum in Kronborg castle, Elsinore, Denmark,[iii] and still looks edible. Hard tack, pilot bread, ship’s biscuit are all versions of a simple type of cracker or biscuit, made from wheat flour, water, and sometimes salt. Inexpensive and long-lasting, these were used for sustenance in the absence of perishable foods, commonly during long sea voyages and military campaigns. They were also one of the first industrialized food products after sugar. Already by the 18th century they were produced in assembly lines in dockyards and by 1833, the British Royal Navy introduced steam-powered machinery to roll the dough and later a Jonathan Dickson of Carlisle invented a mechanical biscuit stamp, an early example of branding.[iv]

Until the 19th century, bakers obtained their yeast from beer brewers, continuing the symbiosis between beer and bread established more than five thousand years earlier. However, beer brewers slowly switched from top-fermenting to bottom-fermenting yeast and this created a shortage of yeast for making bread.[v] This process got a real boost by invention of artificial refrigeration which made it easier to make lager (lager means storage in German) beer. In response, the Association of Viennese Bakers offered a prize in 1845 for the production of a good yeast that was not dependent on brewers. Ironically, it was a brewer, Adolf Ignaz Mautner, who won the prize for the production of press-yeast in 1850. Meanwhile there was a rapid development in milling technology. The marvelous mills of Budapest had steel rollers with a capacity to mill 1 billion pounds of wheat per year. Roller mills allowed the production of white wheat flour, which wasn’t really possible with stone mills. The yeast and the new mills changed the baking-industry throughout the Austrian empire, and at the Paris Exposition in 1867 the Viennese bakery was recognized as the best in the world. The development was so sensational that the United States government printed the Report on Vienna Bread by Eben Norton Horsford in 1875 in which he stated that the purity, whiteness, yield and keeping qualities of the wheat flour of Austria were unequaled in any other country. But this was to change, as everyone followed in the footsteps of Austria.

This industrial development had many effects, reaching far outside the factory gates. White wheat bread in all forms is easy and quick to eat, has not too much taste in itself and can be complemented with various forms of spreads or covers. With industrial yeast it was also quick to produce. It is more voluminous, more porous, and easier to chew. In this sense the bread became something of a pioneer fast food. Another, possibly bigger, effect was that with earlier stone-milling technology the oils of the wheat germ was set free in the flour and caused it to go rancid and have a foul smell if stored for a longer term. Wheat flour was thus a fresh product, milled daily and households bought small quantities from local mills to have fresh flour. The white wheat flour didn’t contain the germ and could be stored for a long time, which meant that traders could buy and store bigger quantities and transport it from where it was cheap to where it was dear. This was the start of a rapid consolidation of mills, aided by the railroads and canal networks, which enabled big mills to both source grain and sell flour over a dramatically bigger area than before. In a few decades small mills closed down and in a later stage the same forces led to the concentration of baking into huge factories. Industrial bread was born.

The industrialization of milling created new opportunities, but also its own set of problems. Whole wheat flour is more nutritious than refined white flour and contains more fiber, protein, calcium, iron, selenium, folic acid, vitamins and omega-3 fatty acids.[vi] Quite soon after the large-scale introduction of white flour a number of diseases emerged. These were often referred to as “western diseases” as they seemed to follow in the footsteps of the spread of a diet of white bread and sugar. This explains why the British working classes, for whom bread was the main source of sustenance, were more malnourished in 1900 than at any time since Tudor times (the period between 1485 and 1603) according to an article in the British Medical Bulletin.[vii] There was an early counter-reaction with strong arguments being made in favor of whole grain bread and the emergence of breakfast cereals and muesli. In 1880, May Yates founded the Bread Reform League in London to promote a return to wholemeal bread, particularly to improve the nutrition of the children of the poor.[viii] It was evident that some of the problems were a result of the victory of white flour, and industry and government responded with a counter-measure in line with the new industrial process, thinking and profits: fortification. [ix]

Flour treatment agents or additives, euphemistically called ‘flour improvers’ alter the appearance and properties of flours in order ‘to better suit their intended purpose’. For example, inspired by a fashion that arose in the 19th century for whiter-than-white bread, bleaching agents such as chlorine are used to whiten flour (unbleached flour has a pale cream color). Oxidizing agents, such as phosphates and ascorbic acid, are used to develop gluten in flour, making it better for baking bread. Potassium bromate, is widely used in United States as an oxidizing agent but has been found to be carcinogenic and is banned in Europe.[x] The German company Mühlenchemie lists no more than sixty-two flour ‘improvers’ on their web site[1]. Many of the additives are composed of several active ingredients, so the total number is even much higher.[xi]

As with many other shifts in technology, the new milling method had repercussions not only on the processing and the final product but also on the raw material. This is often the forgotten part of the story of our food industry. The new milling technology needed harder wheat that could more easily be worked by the new high-speed machinery. Soft wheats, good for stone milling, were replaced by hard wheats. The hard Turkey Red wheat brought to America by Russian immigrants became a major export commodity, largely as a result of the new milling technology, and wheat production in United States tripled in fifty years.[xii] Similarly, the new industrial baking processes needed wheat with certain qualities in order to work well. Only much later did anybody question if these improved technical properties were detrimental to the nutritional quality of wheat.

White flour is not the only reason for our bread having a lower mineral content, cultivation methods and seed breeding that values higher yields ahead of nutritional value have also contributed. Wheat protein is well suited for human nutrition except for a low lysine content. The lysine content is comparatively lower in white than in whole grain flour and lower in heavily fertilized wheat. One variety of wild emmer wheat in Israel has a protein content that reaches forty percent,[xiii] more than three times higher than in normal wheats. The long-term experiments at Rothamstead[2] – which required vision and commitment to establish and maintain - show that the introduction in 1968 of the new ‘Green Revolution’ varieties of wheat was accompanied by a considerably lower content of zinc, iron, copper and magnesium in the flour.[xiv]

There is also a close interdependence between the new varieties and the new cultivation methods. Semi dwarf varieties of wheat were introduced because they had shorter straw and less roots, which meant that more of the biological production went into the seed (the kernel). But this only worked if the plant got more ‘support’ from the farmer, in the form of artificial fertilizers, pest and weed control. Higher yields also often have a dilution effect, with the protein and mineral content going down and the carbohydrate content going up. The highest wheat yields are recorded in West and North West Europe where farmers use a lot of chemical fertilizers to keep the protein level high enough for industrial breadmaking. For example, United Kingdom farmers currently apply 250–300 kg N per ha in order to achieve the 13% protein content required for the breadmaking process that is most common in the United Kingdom. The quantity of fertilizers used is well above what the plants actually take up. The rest is washed away into the waterways as nitrates or goes up into the atmosphere, some of it as the potent climate gas, nitrous oxide (laughing gas).[xv]

In this way, white wheat flour embodies most of the characteristics of the industrialization of food: stripping it to its basic components, giving a longer shelf life, making further preparation easier, enabling large-scale processing, storage and handling, requiring food additives but giving a lower nutritional value. All this is also combined with an increase in environmental damage. This industrialized food system industry drives, and is driven by, changes in marketing and distribution that together determine what and how we eat and how we interact with each other. The genes of the wheat, the yeast and all the processes involved in making our daily bread are all shaped by industrial and marketing imperatives.

[1] This include 3 different fungal α-amylase products; 9 products of the ;amylase-hemicellulase complexes’; beta-amylase, amyloglucosidase, esterase, lipase, ferulic acid esterase, 4 products of hemicellulases, pentosanases and xylanases; 3 products of glucose oxidase, sulphhydryl oxidase, 2 proteases, 5 bromate substitutes, 6 ascorbic acid preparations, 3 bromate products, 3 azodicarbonamide, calcium peroxide, 2 benzoyl peroxide preparations, 3 lecithin products, 3 malt flours, enzyme-active products, 3 cysteine preparations, inactivated yeast, enzyme-mineral complex, and 2 acid and mineral complexes with a buffering effect.

[2] Rothamstead is an English agricultural research station.

[i] Shewry P. R. 2009 ‘Wheat’ Journal of Experimental Botany 60 (6) pp. 1537–1553.

[ii] Ibid.

[iii] Wikimedia ‘Oldest_ship_biscuit-Kronborg-DK.JPG’ Oldest_ship_biscuit-Kronborg-DK.JPG

[iv] Fernández-Armesto, F. 2001 Food, a History Macmillan.

[v] Wikipedia ‘Baker’s yeast’’s_yeast.

[vi] Pollan, M. 2008 In Defense of Food: An Eater’s Manifesto Penguin.

[vii] Welch, R.W. and P.C. Mitchel 2000 ‘Food processing: a century of change’ British Medical Bulletin 2000, 56 (No 1) 1-17

[viii] Shewry P. R. 2009 ‘Wheat’ Journal of Experimental Botany 60 (6) pp 1537–1553.

[ix] FFI Global Update 2008 ‘Flour Fortification Initiative 2008’. URL?

[x] Wilkinson, P.A. et al. 2012 ‘CerealsDB 2.0: an integrated resource for plant breeders and scientists’ BMC Bioinformatics 13 219

[xi] Mülenchemie ‘Products for flour improvement’ 13 December 2013.

[xii] Wikipedia ‘Wheat production in the United States’

[xiii] Shewry P. R. 2009 ‘Wheat’ Journal of Experimental Botany 60 (6) pp 1537–1553.

[xiv] Ibid.

[xv] Ibid.

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