A while back, I read James McCann's book Maize and Grace: Africa's Encounter with a New World Crop, 1500-2000. Beautiful book! Any of you out there who can should grab a copy.
My favourite chapter in the book is "How Africa's maize turned white". It opens with the dramatic events that have characterized and shaped modern Africa, starting in South Africa i.e. mining, industrialisation, European settlement and male migrant labour. Maize is at the heart of all these events. However, whereas maize serves as the native South Africans' staple diet (in mealies and beer), for South Africa's commercial farmers, maize is a traded commodity used globally in industry and as cattle feed (and allied feeds).
According to McCann, native African maize (originally imported from South America during the Columbian era) expressed itself in very different ways on small peasant farms, displaying many colours. Up to the beginning of the 19th century, farmers could choose seed from their previous crop; they also had a variety of coloured maize varieties to choose from (e.g. Blue Flint, which they had by then christened "Blue Zulu"), but the arrival of hybrid maize changed all this. This was preceded by the discovery of diamonds at Kimberley in 1867, which led to an influx of migrant workers and capital, opening up the area for commerce and an increased demand for food. In the late 19th century White American Maize, which birthed the hybrid varieties that would revolutionize maize farming in both Southern and Eastern Africa, was imported. These new (hybrid) varieties were, in addition, high-yielding and utilized commercial fertilizer, making maize farming attractive to large commercial farmers.
While most of the world's maize crop is yellow, Africa produces mostly white maize. Chemically and genetically the 2 varieties are similar, although the yellow maize has a nutritional edge over the white maize because it contains the "carotene oil pigments responsible for the colour of yellow maize". Carotene is a precursor of Vitamin A. Most Africans prefer the white maize and refuse any other colour. In fact, when given a choice, they will pay more dearly for the white variety. This sharply contrasts with earlier Africans who selected "coloured maize ranging from crimson to blue to colourful mosaics of red, blue, yellow and orange." So how did this transformation occur?
This transformation is linked to the commercialization of maize that naturally followed increased demands for the crop. Maize became an exportable commodity which, for the purposes of the British starch and distillery industries, had to be homogeneously white. The South African crop could therefore compete on the international market, and get premium prices as a white homogeneous crop. In Southern Rhodesia, in an effort to force farmers to grow this homogeneous white crop, the cultivation of coloured varieties was outlawed. The flour mills also preferred the hybrid white maize because it was easier to mill, having a softer grain than the other varieties. One author mentioned in the book hints at another reason, divorced from the above two: "The real cause is the tendency of the native to imitate the white man, and that as the white man in Southern Africa eats only white mealie meal, the native thinks he ought to do so too". Contrary to this assertion, however, white South Africans had long identified maize as a "kaffir food".
McCann ends the chapter by reflecting on the political and economic forces inscribed by hybrid maize onto Southern Africa at the end of the 20th century: White farmers prospered while black farmers declined. Medical records from the 1920s and 1930s show that in colonial Basutoland "the incidence of pellagra and kwashiorkor increased in direct proportion to the rising percentage of maize in the diet".