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16 / JANUARY-FEBRUARY 2010, VOL. 55, NO. 1

doi:10.1094/ CFW-55-1-0016

2010 AACC International, Inc.

J. R. N. T ayloRUniversity o PretoriaPretoria, South A rica

S. C. B aRRioNUniversity o NamibiaWindhoek, Namibia.

l. W. R ooNeyTexas A&M University

College Station, TX, U.S.A.

M illets are collectively the worldssixth most important cereal, with anannual production o around 30 milliontons (11). There are many species that arecalled millets. However, pearl millet ( Pen-nisetum glaucum ) (Fig. 1a) is by ar themost important millet, accounting orabout hal o total millet production. Pearlmillet grain is ovoid- to tear-shaped andsomewhat shiny in appearance with acreamy white, gray, or purplish color (Fig.1b). It is so named because o its resem-

blance to seed pearls. The grain is aboutone-third the size o wheat. Despite itssmall grain size, pearl millet has relativelygood nutritional value compared to othercereal grains. This is on account o its pro-portionally large germ compared to en-dosperm. The average at content is around5.1%, with linoleic acid (C18:2) account-ing or some 44% o total atty acids (9).These values are very similar to maize, ap-proximately 5.3% and 44%, respectively(13). The average protein content o pearlmillet (14.5%) is considerably higher thanmaizes (10.5%). Also, the protein is some-

what richer in lysine, the rst limiting in-dispensable amino acid, 3.3% compared to2.8%. As pearl millet is closely related tomaize and sorghum, it is gluten ree.

Ancient Grain and Modern DayCultivation

Pearl millet was rst domesticated inA rica some 5,000 years ago (1). It is auniquely hardy crop cultivated in regions

with very high daily average temperatures,up to about 30 C and very low annualrain all, down to 250 mm (7). In A rica,pearl millet is extensively cultivated acrossthe western side o the continent rom theSahel (Sahara Desert margin) in West A -rica, down to Namibia and South A ricaand the eastern side o the Sahara desert

rom Sudan into East A rica. It is also animportant crop in the dry sandy areas o India, such as Rajasthan and Gujarat.

In A rica and India, pearl millet is al-most exclusively cultivated by smallholder

armers and has up until very recentlybeen regarded as a subsistence crop. How-ever, because o its hardiness, pearl milletis becoming a commercial crop in otherarid regions o the world, or example, inthe state o Georgia (Fig. 1c) (5), Austra-lia, and Brazil (Fig. 1d). In the southeast-ern United States, it is grown on nearly

three million hectares as a orage crop be-cause o its disease resistance. Varietiesgrown in Georgia are or special use in

oods, pet oods, and related products.Production is grown under contract andthe grain is harvested at high moisture andthen dried to avoid discoloration. Pearlmillet is grown in Brazil on the dry prai-

ries where it is a pre erred part o the crop-ping systems used on these special soils. Itprovides the necessary soil amendments toimprove soybean production signi cantly.

A rica is urbanizing rapidly. In the 50years since 1960, the percent o A ricansliving in urban areas has more than dou-bled rom 18 to 40% (12). The percent in-crease o urban dwellers in North Americawas much smaller (69 to 78%). The rapidincrease o urban people in A rica is ex-pected to continue, with a doubling innumber by 2030. The United Nations

FEATURE

Pearl MilletNew Developmentsin Ancient Food Grain

How is pearl millet, an ancient hardy grain, becoming an important cash cropin arid regions around the world?

How are entrepreneurs in A rica making value-added ood products rompearl millet or the newly urbanized population?

This article discusses the applicability o these pearl millet products to ethnicand health ood markets across the world.

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CEREAL FOODS WORLD / 17

Population Fund sees the rapid urbaniza-tion in A rica and Asia as unleashing thepotential or growth. In the context o cereal oods, urban amilies are o ten away

rom home and do not have time to preparetraditional meals starting with millinggrain to four. However, they like the tradi-tional oods they were brought up on andwill pay or convenience and quality com-bined with tradition. This paradigm shi t is

creating a demand or the commercialmanu acture o innovative value-addedcereal ood products by entrepreneurs, in-cluding many made rom pearl millet (14).Millet production in A rica is increasingsubstantially. From 1982 to 2007, milletproduction (mainly pearl millet) rose rom7.6 to 17.2 million metric tons (4). Thisgrowth is continuing and now modern ag-ricultural practices are being applied as itbecomes a commercial commodity. Forexample, in 2009, some 1,700 hectares o new technology plantings using improvedmillet and sorghum cultivars are taking

place in Sahelian countries, according toJohn Sanders, agricultural economist, Pur-due University.

This article describes new developmentsin pearl millet ood products in A rica thatalso have potential in other parts o theworld. Two levels o value addition can bedistinguished: four products (the morebasic) and ready-to-eat (RTE) oods. Ex-amples o each will be described below.

Flour Products Milling

In Namibia, pearl millet is the most im-

portant staple cereal ood grain (3), whereit is known as mahangu . Pearl millet fouris made into thick porridge ( oshifma ), thinporridge ( etete ), pancakes ( omungome ),and even cake ( oshikwila ). Traditionally,people in Namibia pre er pearl millet fourwith a slightly sour favor, resulting romlactic ermentation during milling. As willbe seen, acidic pearl millet oods are popu-lar across A rica.

In the traditional milling process, thegrain is conditioned with water and deb-

ranned using a wooden mortar and pestle.The debranned grain is steeped or one totwo days at room temperature in water, al-lowing lactic acid ermentation. This er-mented grain is partially dried in the sun(10), milled into four using a mortar andpestle, and then the four is dried in the sunprior to storage.

Today, commercial millers use locallymade abrasive disk dehullers to debran the

pearl millet grain (Fig. 2a). This type o dehuller was originally developed by theCanadian Prairie Research Laboratory (2)to debran barley and oats. The debrannedpearl millet is then steeped (Fig. 2b) andpartially dried (Fig. 2c), and the dampgrain is milled into four using hammermills (Fig. 2d). The four is then sun driedand bagged or sale (Fig. 3a).

Thus, traditional pearl millet milling isboth laborious and ine cient. Today inNamibia, pearl millet four is also producedby large-scale industrial milling. The grainis mechanically debranned by abrasion, es-

sentially as described above. This productis sold as pearl millet rice. To producefour, the rice is milled by roller milling,sized, and puri ed using plansi ters andpuri ers rom wheat milling equipment.

Table I gives the physical and chemicalcomposition o pearl millet fours pro-

duced by both processes. Although theproximate composition o the fours issimilar. Noteably, the four produced bythe industrial milling process is darker incolor and higher in total polyphenols andn-glycosyl favones than the traditionallyproduced four. This can be attributed to itsslightly higher extraction rate resulting inthe four containing more o the pericarpwhere the phenolics are concentrated, and

to the absence o the steeping processwhere some o the phenolics would be

Fig. 1. Pearl millet. a) experimental arm inKenya showing resistance o bristled typehead to bird predation (le t) versus normaltype (right); b) grain o variety SDMV 89004developed in Zimbabwe; c) under cultivationin Georgia (U.S.A.); and d) under cultivation inBrazil (courtesy o Je Wilson, USDA).

Fig. 2 Traditional mahangu (pearl millet) mill-

ing in northern Namibia. a) PRL type dehuller;b) steeping (lactic acid ermentation) vessels;c) sun drying the ermented grain; and d) ham-mer mill.

Table I. E ects o the traditional semiwet and industrial dry milling processes on the physical and chemical composition (dry basis) o pearl milletfours a

Flour Color Carbohydrate Total C-glycosylSample extraction rate (N x 6.25) Protein Ash (starch) Fat polyphenols favones

(%) (L) (g/100 g) (g/100 g) (g/100 g) (g/100 g) (mg/100 g) (mg/100 g)

Whole grain 100 53.3 a 14.8 c 1.6 c 4.86 c 59.8 a 150 c 118.0 c

Traditional 88.1 76.5 c 13.2 a 0.76 a 3.84 a 70.8 b 80 a 60.7 ahand-pounded and (89.2) (46.3) (79.0) (118) (53.4) q (51.4)hammer-milled

ermented four

Industrially 92.7 74.8 b 13.4 b 1.12 b 4.08 b 69.8 b 140 b 64.8 broller-milled four (90.5) (68.3) (84.0) (117) (93.3) (54.9)

a Figures in columns with di erent letter notations are signi cantly di erent at P < 0.05. Figures in parentheses are percentages o whole grain composition.

Fig. 3. Pearl millet our products. a) tradi-tional produced our rom Namibia; b) indus-trially produced pure pearl millet andcomposite pearl millet-maize ours rom Na-mibia; c) composite presoured uji our romKenya; d) our rom Mali; and e) semolina

rom Senegal.

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leached out. The industrially milled fouralso lacks the traditional sour favor.

Enriched FloursIndustrially milled pearl millet four is

marketed as a product by itsel and as acomposite with maize four (Fig. 3b) ormaking porridge. Composite pearl milletand wheat fours have applications in pas-ta, bread, biscuits, and other bakery prod-ucts. A commercial process or making

the traditional pearl millet cake, oshik-wila , with added marula oil has been de-veloped. In Senegal, composite wheatbreads containing pearl millet four arequite popular in many small bakeries.

In Kenya, pearl millet is compositedwith a variety o other cereal fours, includ-ing nger millet, sorghum, and wheat incommercial four products or making uji (thin porridge) (Fig. 3c). The KenUji prod-uct shown is particularly interesting in thata souring agent, a ruit acid, is included inthe ingredients. The purpose o this is togive the porridge an acidic favor, mimick-

ing the traditional lactic acid favor, butwithout the need or ermentation.

and 4c, respectively. The commercial pro-cess o making sorghum and millet cous-cous involves decorticating the grain withan abrasive dehuller (Fig. 5a). This partic-ular type o dehuller is specially developed

or pearl millet in that the bran is removedby revolving brushes rather than aspira-tion, as in the type shown in Figure 2a (2).The revolving brush system reduces losseso ne-grain particles. Therea ter, the

grain is milled into four with a hammermill. The couscous is produced rom thefour by repeated agglomeration, steaming(Fig. 5b), and si ting o the particles to auni orm size (Fig. 5c) (6). Attempts havebeen made to mechanize the agglomera-tion and si ting process but they have notbeen widely implemented.

A very innovative and popular commer-cial product produced in Dakar, Senegal,is yogurt containing millet couscous (Fig.4d). This product is based on a traditional,soured, custard-like product in the Sahelregion called thiakri (thiacry or tiakri ),

and is another example o the diverseacidic-favored A rica pearl millet oods.The production o yogurt has spread tomany West A rican countries where pearlmillet or sometimes sorghum couscous orother cooked agglomerated products areused in RTE products. These productshave excellent favor and their quality isconsistent. Several small processors areinvolved and have developed supply chainmanagement systems to obtain good qual-ity grain or processing. This is essential i high-quality products are going to be pro-duced, since the pearl millet can have 10

20% impurities, including sand, etc.Excellent progress is being made by work-ing with armers, suppliers, and processorsto secure and pay or high-quality grains.

Perhaps the most interesting RTE pearlmillet-based ood product that the authorshave come across is instant weaning por-ridge, made in Ouagadougou, BurkinaFaso (Fig. 6a). Pearl millet and maize are

rst debranned and then milled into four.Two alternative processes are then used toprecook the four. In one process, sti dough is rst made by mixing four andwater. The dough is then baked using acontinuous oven originally designed ormaking cookies (Fig. 6b). Alternatively, asmall extrusion cooker is used (Fig. 6c).The cookies, or extrudate, are milledinto four and a vitamin and mineral pre-mix is blended in.

To illustrate one o the problems thatsmall entrepreneurial ood manu acturersin A rica ace, we re er to a similar prod-uct composed o decorticated pearl milletand cowpeas that was produced commer-cially in Mali during the mid 1980s. It toowas sold as a weaning ood or children

Fig. 4. Ready-to-eat pearl millet products. a)instant tamarind- avored gruel rom Nigeria;b) couscous rom Senegal; c) couscous romSenegal; and d) thiakri millet and yogurt romSenegal.

Fig. 5. Pearl millet couscous manu actured inSenegal. a) dehuller; b) steamer; and c) ag-glomerating and si ting the couscous.

Fig. 6. Commercial instant pearl millet andmaize in ant ood manu acture in BurkinaFaso. a) in ant ood product; b) cooking thedough with a continuous oven; and c) a smallextruder or cooking the our.

Figures 3d and 3e show pearl milletfour and semolina products rom Maliand Senegal, respectively. The ormer ispackaged in a polyethylene bag or localsale, whereas the latter is in a cardboardcarton with elegant labeling and is aimedat the gluten- ree market in Europe.

Since pearl millet grain cannot be im-ported into the United States, there is alarge niche market or similar products

rom people who were originally rom theIndian subcontinent. Pearl millet is o tenpre erred by Indians and Pakistanis whogrew up consuming it in a wide variety o

oods, including fatbreads (roti, chapat-tis), parched or expanded grains, rice,and porridges. The varieties o pearl mil-lets pre erred are quite dark in color. Thesecould be grown in the United States andthe relatively high value o the productsmake it an attractive crop to consider.

RTE FoodsRTE pearl millet four products are sub-

stantially less common than enrichedfours, probably because the technology ismore sophisticated and they are more ex-pensive with a much smaller market. InNamibia, there is a pearl millet-sorghuminstant four product or making the tradi-tional millet beverage called oshikundu. Figure 4a shows a similar extrusion-cooked instant four rom Nigeria or mak-ing an RTE version o the traditionalNigerian pearl millet porridge kununtsamiya , which literally means gruel o tamarind. The product is favored withtamarind oil, another example o an acid-

favored A rican pearl millet ood.In the Sahel region, couscous made

rom pearl millet and sorghum is a verypopular, traditional staple ood. Commer-cially produced millet and sorghum cous-cous products rom Senegal aimed at theupscale local market and created or ex-port to Europe are shown in Figures 4b

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and was success ul but it could not com-pete with imported products because o inadequate supplies o grains o suitablequality or processing. The millet andcowpeas had very high levels o impuritiesthat also drove up the price.

Concluding RemarksThis article shows that across A rica,

pearl millet is moving rom a subsistence

grain to an important ingredient in a widerange o added-value competitive ancientgrain ood products, which could ndvaluable niche markets in other parts o the world as health and ethnic oods. Un-

ortunately, there are still several obstacleshindering this important economic devel-opment. Although millet production is in-creasing in A rica, crop yields remain verylow, on average only about 700 kg/ha (4).This is attributed to poor agricultural prac-tices, slow adoption o improved varieties,and crop losses due to biotic stresses, in-cluding birds (Fig. 1a, right). There is also a

chicken-and-egg situation. Farmers willnot spend money to improve productivityunless there is a pro table market or theirgrain. At the same time, entrepreneurs willnot use pearl millet as an ingredient unlessthere is a constant supply o reliably qual-ity grain available at an economical price.Thus, the lack o pearl millet or processingin large quantities is a major disadvantageo this unique ancient grain. The solutionto this seems to be the application o a sup-ply chain management strategy, wherebyall the constraints rom arm to ork areaddressed in a coordinated manner (14).

Application o this strategy, including thecultivation o improved cultivars, use o inorganic ertilizers, simple post-harvestgrain handling techniques to produce cleangrain, and sound grain market practices,have resulted in dramatic increases in sor-ghum and millet yields and pro tability or

armers in countries, such as Mali, Niger,and Senegal (8).

AcknowledgmentsThe authors wish to thank the Sorghum, Millet,

and Other Grains Collaborative Research SupportProgram (INTSORMIL) or unding part o thiswork and the proprietors o the Jaboot (Dakar) andSodepal companies (Ouagadougou) or kindlyhosting us and permitting us to take photographs.

References 1. Andrews, D. J., and Kumar, K. A. Pearl millet

or ood, eed, and orage. Adv. Agron. 48:89,1992.

2. Bassey, M. W., and Schmidt, O. G. Abrasive- Disk Dehullers in A rica . International Devel-

opment Research Centre, Ottawa, Canada,1989.

3. Du Plessis, P. Promoting Mahangu and Sor-ghum in Namibia . Namprint, Windhoek, Na-mibia, 2001.

4. FAOSTAT. A rica, Millet, Production. Pub-lished online at http:// aostat. ao.org.

5. INTSORMIL. An A rica Pearl Finds a Homein the U.S., Report No. 9. Published online atwww.ianr.unl.edu/INTSORMIL/sm2007%20Flyers/Brie %209%20Pearl%20millet%20U.S.doc.pd .

6. Murty, D. S., and Kumar, K. A. Tradi-tional uses o sorghum and millet. Pages 185-223 in: Sorghum and Millets: Chemistry and Technology. D. A. V. Dendy, ed., AACC Inter-national, St. Paul, MN, U.S.A.1995.

7. National Research Council. Lost Crops o A -rica. Vol 1: Grains . National Academy Press,Washington, DC, U.S.A., 1996.

8. Sanders, J. Development o the input andproduct markets in West A rica or sorghumand millet. Pages 8992 in: INTSORMIL Sor-ghum, Millet and other Grains CollaborativeSupport Program Annual Report 2008 , Uni-versity o Nebraska, Lincoln, NE, U.S.A.Published online at www.intsormil.org.

9. Serna-Saldivar, S., and Rooney, L. W. Struc-ture and chemistry o sorghum and the millets.Pages 69124 in: Sorghum and Millets: Chem-istry and Technology. D. A. V. Dendy, ed.AACC International, St. Paul, MN, U.S.A.,1995.

10. Taylor, J. R. N. Millet: Pearl. Pages253262 in: Encyclopedia o Grain Science .C. Wrigley, H. Corke, and C. E. Walker, eds.Elsevier, London, 2004.

11. Taylor, J. R. N., and Emmambux, M. N.Millets. Pages 119148 in: Gluten-Free Cereal

Products and Beverages . E. Arendt and F. DalBello, eds. Academic Press, San Diego, CA,U.S.A., 2008.

12. United Nations Population Fund. Stateo the World Population 2007. Unleashing thePotential or Growth. Published online atwww.unp a.org, 2007.

13. USDA Nutrition Database. YellowCorn 20014. Published online at www.nal.usda/gov/ nic/ oodcomp/search.

14. Vitale, J. D., and Sanders, J. H. Newmarkets and technological change in tradi-tional cereals in semiarid sub-Saharan A rica:The Malian case. Agric. Econ. 32:111, 2005.

John Taylor is a pro essor o ood science at the University o Pre-toria. He undertakes research into the science and technology oA rican cereal grains, especially sorghum and millets. Taylor hassupervised some 70 masters and doctoral research students romacross A rica. He is the author o more than 200 scientifc publica-tions, technical reports, and popular articles on A rican cereals.Taylor has organized numerous symposia and short courses oncereal processing with the aim o improving A ricas ood security.He is a ellow o AACC Intl. and a recipient o the associationsExcellence in Teaching Award. Currently, he is president o the In-ternational Association or Cereal Science and Technology (ICC).

He can be reached at John.Taylor@up.ac.za.

Stephen Barrion has been lecturing at the Department o Food

Science and Technology, University o Namibia, since 2004. Prior tohis appointment at the university, he worked in some o Namibiasood industries, including Namibia Breweries Limited. He served as

a project manager or the Partnership or Food Industry Develop-ment Project (20052007)a USAID- unded collaboration with theLouisiana State University Agricultural Center. The project wasaimed at promoting value addition in the Namibian ood industry;enhancing ood sa ety and quality capabilities and practices in themeat, sea ood, and poultry sectors; and the establishment o pro-

ducer-processor linkages. He can be reached at stephen.barrion@gmail.com.

Lloyd W. Rooney , Regents Pro essor and aculty ellow, CerealQuality Lab, Soil & Crop Sciences Department, Texas A&M Uni-versity, teaches cereal technology/chemistry and related courses.He has chaired or cochaired 64 M.S. and 41 Ph.D. students, andserved as chair o the Food Science Intercollegiate Graduate Fac-ulty. He participates in post-harvest technology and research anddevelopment programs in A rica, Asia, Europe, Mexico, Central,and South America, ocusing on corn, wheat, and sorghum pro-cessing quality. His research has resulted in numerous wheat cul-tivars and sorghum hybrids. The Snack Food Processing coeditorhas more than 300 publications on cereal processing, chemistry,

quality, and nutrition. He can be reached at lrooney@tamu.edu.