Food series: Sorghum, Developed by Africa and more healthy than wheat (9,500 BCE – 7,000 BCE)

Sorghum, also known as great millet or milo, is the 5th most important and cultivated cereal crop in the world after wheat, rice, maize and barley. The name “sorghum” is derived from Italian word “sorgo”, which is a modification from Latin “Syricum (granum)” which means “grain of Syria”. It has a variety of uses from human consumption, to animal feed to even ethanol production. It is grown extensively in the warmer areas of the world, mainly Africa and southern and western Asia. It has long been the staple food of millions of people in these areas owing to its high protein content (9%), the genius of pre-historic Africans and its ability to grow in very harsh conditions. It was first cultivated around 9500 BCE to 7,000 years BCE in the eastern Sudan near the Atbara and Gash rivers. From there it rapidly spread across the eastern African coastline and towards the western Asian coastline through ancient traders. Since this was before rice had become cultivated, sorghum soon became the staple food for a lot of ancient kingdoms.

However, despite being one of the most vastly cultivated crops, developed early in the history of farming, and arguably originating before even rice did, the history of Sorghum is relatively obscure. There is a dearth of knowledge about Sorghum in terms of the timing and location of domestication, ecological environment, and the nature and length of this process.

Sorghum (source)

Scientific Background

Sorghum is a genus of flowering plants in the grass family Poaceae. This family consists of around 25 species, of which around 8 are commercially viable for various purposes. One species is grown for grain for human consumption, namely the Sorghum Bicolour, while many others are used as fodder plants, either cultivated in warm climates or left to grow wild, in pasture lands. Sorghum is in the subfamily Panicoideae and the tribe Andropogoneae.

History of Cultivation

The history of cultivation of Sorghum is relatively unknown. Even though it has been found extensively in old ruins, as a part of central silos or even inside homes, especially in Northeastern Africa and Southern Asia. The oldest example in Asia is from India, dated to the second millenium. However it is known that sorghum is not native to Asia but to Africa, hence the history of its cultivation dates much farther back to between 9,500 BCE and 7,000 BCE in Africa.

In fact the oldest evidence of sorghum has been found in Northeastern Africa. The record comes from an archeological dig at Nabta Playa, near the Egyptian-Sudanese border. This site has been dated to be occupied somewhere around tenth and eighth millennium BC. The people at the time were found to have stored wild sorghum, which they presumably then started to domesticate.
From then the next major milestone is the evidence of sorghum cultivation in Sudan, dated to around fourth millennium BC. The evidence for this comes mainly from the Kasal regios, where evidence for threshing waste, including spikelets from domesticated type sorghum plants was found. The implication of this evidence is that sorghum was being cultivated around Khashm el Girba between 3500 and 3000 BC.

Spread of sorghum through the African continent

To understand the significance of the threshing waste, and to further examine the spread of sorghum, scholars of history have fallen back on the study of the genetics of the sorghum plant. It is known that wild sorghum had a completely hulled grain. Hence when evidence of partially hulled grain was found (named bicolour), it was deduced that this was the first domesticated strain of sorghum.

Various husks of the different races of Sorghum

Early domesticated race spread to South Asia around 2000 BC and to the Niger Basin in West Africa after 1000 BC. From this initial grain 5 major races of sorghum were bred. These new strains had an important focus on being able to free thresh the grains to make the process of their consumption easier.

These 5 races of sorghum spread rapidly throughout the world, eventually finding its way to the United States in 1767.

Use as food crop

Sorghum is a very popular food crop in Africa and Asia. It has a very high protein content (nearly 9%) and is a drought resistant crop, making it an ideal staple of diet for many people. It is used in a variety of ways in different parts of the world. While the main usage is directly processing it into flour, which is used for making flat bread which from the staple of many cultures, Sorghum has many other uses as well. For example:

In several countries in Africa, including Zimbabwe, Burundi, Mali, Burkina Faso, Ghana, and Nigeria, the traditional opaque beer called umqombothi is prepared with sorghum. Red sorghum imparts a pinkish-brown colour to the beer.

In China, sorghum is known as gaoliang (高粱), and is processed similar to rice (fermentation and distillation) to produce a clear spirit known as baijiu (白酒). The most famous example of Baiju spirit is the Maotai (or Moutai). Sorghum flour was the main alternative for wheat in China for a very long time.

In India, where it is locally known as jwaarie, jowar, or jondhalaa, Sorghum is a primary source of nutrition for many cultures. An Indian baked flat bread called bhakri(or jowar roti) is prepared from sorghum flour. This grain is also used for religious purposes by some sects in India. During the 9-nights festival of Navratri, jowar grains are planted and the young stalks are harvested and used as offering for the ceremonies.

Sweet sorghum syrup is often used as molasses in some parts of the United States.

In Central America, traditional flat breads called tortillas are often made with sorghum. White sorghum is preferred for making tortillas.

Sorghum is also widely being used recently as a wheat substitute for gluten free diets.

Health Benefits of Sorghum

In the modern-day people have begun to appreciate sorghum as a healthy alternative to wheat for a lot of diets. Sorghum is completely gluten free, and hence is a staple grain for individuals suffering from celiac disease and other gluten intolerances. Sorghum also has high nutritional value, with high levels of unsaturated fats, protein, fiber, and minerals like phosphorus, potassium, calcium, and iron. It also has more antioxidants than blueberries and pomegranates.

Sorghum is also the ideal grain for diabetics. This is because sorghum bran is rich in tannin and in enzymes that help to inhibit the absorption of starch by the body, which can help to regulate insulin and glucose levels in the body. Thus, diabetics are spared from plunges and spikes to their glucose levels.

These factors combine to make it one of the most well-rounded grains in the world. Sorghum flour is used to replace wheat in many recipes. In the areas of the world with high sorghum consumption, it is made into porridge or boiled like rice to be used as a base for other dishes.

Use of Sorghum as source for Ethanol

One of the many uses of sorghum is the production of ethanol. The stems of this plant are rich in natural sugars, which are used to make molasses. These molasses, similar to molasses formed using the sugarcane plant, can be used as a base for creation of ethanol.

First the sorghum grains are harvested from the stalks, leaving the stems behind as a waste product. These stems are pressed in an industrial juicer which removes the sugary juice, which is used to make molasses via rigorous heating. These molasses are then fermented using yeast. This mixture is then distilled to produce ethanol.

This is mainly done in India, China and Australia, where ethanol is being pursued as a biofuel to replace the overdependence of these countries on imported oil.

Africa and Sorghum

The continent produces about 20 million tonnes of sorghum per annum, about one-third of the world crop. However, sorghum is most widely consumed grain in Africa, making it so that even despite its massive production, Africa ends up importing a lot of this grain. These imports arrive mainly from Asian countries like India and China, while nearly 100% of sorghum imports in South Africa are from the United States.

Thus, we see that sorghum is a very healthy grain, being the staple diet of millions across the world and being slowly accepted by western nations as a healthy alternative to wheat. While sorghum is busy being an important food crop, it is also being extensively utilized for various other purposes from producing local alcoholic beverages, to producing artwork in Korea. It is also a key biofuel and it is helping countries go greener. Once these factors are properly considered, one begins to see why sorghum is considered the 5th most important cereal crop in the world.

Africa has been blessed with the perfect climate to rear sorghum in, and in doing so it can provide for the majority of the world’s rising demand for sorghum. Since 2005, sorghum production has risen by nearly 66% worldwide, making it a very lucrative opportunity for growth. This is the time when we can help Africa shed its backward image and emerge forward in today’s time, by focussing on growth in its agricultural sector. It will not only make Africa self-sustaining in terms of food, but provide levers to develop into a global net exporter and rather than a net importer.

References

de Moulins D, Phillips C, Durrani N (2003) The archaeological records of Yemen and the question of Afro-Asian contact. In: Neumann K, Buttler A, Kahlheber S (eds) Food, fuels and fields: progress in African archaeobotany. Heinrich Barth-Institut, Cologne, pp 281–299

Dorian Q. Fuller, Chris J. Stevens (2016) Sorghum Domestication and Diversification: A Current Archaeobotanical Perspective. In: Anna Maria Mercuri, A. Catherine D’Andrea Rita Fornaciari, Alexa Höhn : Plants and People in the African Past Progress in African Archaeobotany, pp 427 – 452

Winchell F, Stevens CJ, Murphy C et al (2017) Evidence for sorghum domestication in fourth millennium BC eastern Sudan: spikelet morphology from ceramic impressions of the Butana Group. Curr Anthropol 58(7):673–683

Zohary D, Hopf M, Weiss E (2012) Domestication of plants in the Old World. Oxford University Press, Oxford