Wheat is basically a grass that provides… 21% of food calories globally… (shocked emoji!).
It is one of the earliest plants to have been domesticated and has been cultivated for so long by mankind that it would no longer survive in the wild. It is an absolute product of nature and culture working together and one of the most prominent food crops world wide.
We eat the seeds - except that, in order to eat them, we have to process them in such a way as to make them palatable and digestible. Grinding the grain (seeds) allows us to produce flour. Different flours (white vs whole wheat etc) use more or less of the whole wheat grain, but the most important contributor to flour is the endosperm of the seed, which contains the gluten. It is the gluten that allows us to make bread and which can contribute much of the nutrition long sought after by man.
John M Warren explains that “one of the genes that was incorporated into bread wheat from its goat grass parent, codes for gluten production. This piece of genetic material enables wheat to produce large amounts of protein in its grains. This gluten protein is essential in the bread making process, because by trapping bubbles of carbon dioxide… it causes the dough to rise. …without gluten, bread would be hard and heavy.” (109 The nature of crops) Gluten intolerance has become much more of an issue in recent decades, but for many people, properly fermented wheat is no bother at all to their digestion.
In terms of bread, the other cereals (rye, barley, oats, maize, millet, rice, etc) can also be ground to make flour just like wheat, but with so much less (or no) gluten in them, they make much heavier denser breads. Structurally, most of these seeds are very similar to wheat (hence flour), but chemically, they are quite different.
There are so many breeds and varieties and types of wheat that it would probably shock you. Different wheats have different gluten yields, different flavor profiles, different climactic and seasonal preferences. Which of these wheats is currently being made into flour is determined by the grower, the miller, and (with luck!) the baker, each of whom have their own interests and preferences. So; wheat is as subject to fashions as any other product of culture, in that it changes depending on ‘who’s buying’. My point? Well, two points: 1. The wheat flour you are so used to buying is really just one option of the many that are actually out there, and 2. Things are changing; heritage wheats and different grains are becoming fashionable again. You might soon be able to taste different wheats. How cool is that?!
Of course… there is a major constraint on this; one of the reasons so few bakers actually use organic flour is this changing profile that makes it so unpredictable and inconsistent to work with. You can do it, of course; milling the wheat that’s in season and working with the gluten yield provided by that season’s growing, but few customers want to buy bread that changes so much from day to day and season to season. Also, let’s face it; the cost of organic is about three times higher, which gets to be a pretty expensive bread. Today’s flour companies blend different seasons’ grains to get a consistent quality.
Biologically speaking…
Basically, think about your school biology: water the seed and it germinates, right? A plant grows? Well, each seed carries the food it needs to germinate inside its hull. While the seed is dry, it can keep for a long time: add water and things start happening! What’s so cool is that we can harvest that seed, mill it to get the ‘food’ out in the form of flour, add water and (with a bit more work) make food for ourselves.
Wheat forms an oval seed or grain. It is made up of a few basic parts; the endosperm, which is the largest bit, where the gluten and starch (the food for the embryonic plant) are found; the embryo itself (the ‘wheat germ’ that is milled out of white flour because it has enough oil in it to affect the potential shelf life of flour by making flour go rancid, but which is still sold separately because it offers plenty of nutrition); and the outer layers, which are much more fibrous and basically milled out of flour because they give it a coarse, dark character (you can still buy this as bran in the supermarkets - or wheatbix!).
FYI: if you’re into genetics and stuff, you might like to know that bread wheat (Triticum aestivum) has a “complex impressive genetic history that has seen it hybridised twice.” (107 The nature of crops). Apparently amazing stuff… my genetics is too old to share the joy but I could tell it was there in John Warren’s book. If it impresses you, then good; wheat is impressive!
Wheat and flour milling in New Zealand
Wheat came to New Zealand in the early years of the country’s colonisation by Europeans. In the early 1800s, Maori and European settlers both took to farming wheat and other grains to feed local populations. At that time, before the introduction of the railways (and the more efficient transportation possibilities of trains), there were small mills all over the country. Apparently, between 1834 and 1918, there were over 300 mills built in New Zealand. These days, in contrast, there are fewer than ten mills in New Zealand (excluding the smaller mills of artisan bakeries WATCH THIS SPACE). Basically; “As the colony’s transport infrastructure developed it gradually became more economically sensible to produce flour closer to larger centres of population, or closer to the main areas of wheat production.” (p.11 Flour Milling in New Zealand) This trend has continued and the costs of transportation (including those between Australia and NZ and South Island and North Island) now mean that much of the flour used in the North Island is imported from Australia, while the South Island is more able to use locally grown grain.
Further reading and references:
Dave McKinnon and Geoff Tempest (2015) Flour Milling in New Zealand: How today’s industry evolved. New Zealand Flour Millers Association Research Trust, Christchurch
Edward Hyams (1971) Plants in the service of man; 10,000 years of domestication. J M Dent & Sons Ltd, London
John M Warren (2015) The nature of crops: How we came to eat the plants we do. CABI. Wallingford, Oxfordshire
Carolyn Fry (2016) Seeds; A Natural History. The University of Chicago Press. Chicago (21% global calories statistic p27)