Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/20/2006
Publication Date: 9/6/2006
Citation: Taylor, J.R., Schober, T.J., Bean, S. 2006. Novel and non-food uses for sorghum and millets. Journal of Cereal Science. 44(3):252-271.
Interpretive Summary: Sorghum and millets are, in general, the most drought-tolerant cereal grain crops and require little input during growth. With increasing world populations and decreasing water supplies, they represent important crops for future human use. While sorghum and millets are vital food crops for millions of people in parts of Africa and Asia, they are an underutilized resource in most developed countries, with sorghum being primarily used as animal feed and having only a small amount of millet cultivated. Their commercial processing into value-added products in developing countries stimulates economic development. In developed countries in particular, they can provide products for people with celiac disease, because they are gluten-free. This literature review focuses on novel food uses for sorghum and millets (wheat-free bread, cakes, cookies, pasta, a parboiled rice-like product and snack foods), brewing of lager and stout beers, and bio-industrial products (fuel ethanol, biopolymer films from kafirins, coatings from pericarp waxes). In snack foods, the bland flavor and light color of US white food-grade sorghum hybrids was found to be preferred in several countries. This may open new markets for US grain sorghum producers.
Technical Abstract: Sorghum and millets have considerable further potential in foods and beverages. Their commercial processing into value-added products in developing countries stimulates economic development. In developed countries in particular, as they are gluten-free, they can provide products for people with coeliac disease. Sorghum could be important for fuel ethanol and other bio-industrial products. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. In snack foods, the bland flavour and light colour of US white food-grade sorghum hybrids may be an advantage. Wheat-free sorghum or millet bread remains the main challenge, although it has been successfully produced by several research groups. Additives like native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improved quality. However, specific volumes were lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tended to stale fast. Brewing lager and stout beers with sorghum is taking place commercially. Sorghum's high starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of sorghum malt for barley malt. The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum fuel ethanol production research has focused on improving the economics of the process through cultivar selection, method development for low quality grain and pre-processing to recover valuable by-products. Some potential by products, the kafirin prolamin protein and the pericarp wax, have been found to have potential as biopolymer films and coatings for foods, primarily on account of their hydrophobicity.