In North America, it is an expensive, specialty flour. To get it cheaper, try looking in ethnic stores such as Indian, where it might be called jowar or juwar.
The big issue to overcome with sorghum flour is a certain dryness in baked goods, which shows itself in a coarser crumb, a generally drier taste, and a product more inclined to crumble. This occurs because Sorghum Flour lacks gluten, and therefore the same binding properties as wheat flour would.
These are some of the ways in which you can compensate:
- Per cup of sorghum flour being used add around 1/2 tablespoon of corn starch for baked goods or 1 tablespoon for breads;
- Adding a bit more fat or oil for moisture improvement;
- Extra egg for a finer crumb;
- Extra leavener (baking powder or soda or yeast) to help rising.
If people have a diet that is too exclusively based on sorghum, they can develop pellagra, a disease also experienced by people whose diet relies too much on corn untreated with lye. See the entry on Corn. Though sorghum seems to be one of the latest flours to be keened about by the Health Foodies, there is no solid, consistent nutritional information, and no hard science that it is any more nutritious than good old wheat flour. Certain varieties of Sorghum Flour (i.e. Sorghum Black, bran) have been rated by the USDA as being high in anti-oxidents.
In fact, the UN’s Food and Agriculture Agency says: “The nutritional quality of sorghum and millets, especially the former, is poor. Therefore attempts have been made to fortify these cereals with legumes or other cereals to make nutritionally superior and acceptable products. Cost, availability of ingredients and marketability must be taken into consideration if fortification is to be implemented successfully on a sustained basis.”
It appears its main values are (a) it will grow as a subsistence crop in arid regions of the world as food for the poor and (b) in the first world, it provides a welcome change to potato-starch cookies for those who need gluten-free flour.