Sorghum Grain. Uses of. in Gluten-Free Products. Sorghum is a major cereal grain in the. M. Asif, L. W. Rooney, FEATURE

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1 Sorghum Grain in Gluten-Free Products Uses of FEATURE Image Shutterstock M. Asif, L. W. Rooney, D. Acosta-Sanchez, C. A. Mack, and M. N. Riaz Texas A&M University College Station, TX, U.S.A Sorghum is a major cereal grain in the semi-arid regions of the world and is an important food and feed crop. In the semi-arid tropics of Africa and India, sorghum grain is a staple food for large populations. Nearly all of the grain is used directly as human food. Sorghum is grown in harsh environments with limited water resources and with minimum inputs. The United States is a major producer of sorghum; however, the grain has traditionally been used as feed. Currently, sorghum is gaining new consumers, especially for gluten-free markets. An Answer for Celiacs Celiac disease (CD) is an immunological response to gluten that is increasingly prevalent. CD is an inherited autoimmune disease that affects the small intestine (7). When a person with CD consumes gluten, doi: / CFW AACC International, Inc. Sorghum s popularity continues to grow due to its bland flavor, low cost, increasing availability, and its ability to be blended into various products without eclipsing the tastes of the other ingredients. Sorghum produces unique products with varying tastes that contain high levels of antioxidants and other phytochemicals which may have antiinflammatory, anticolon cancer, and other healthy attributes. Certain sorghums can be easily processed into food products through extrusion, steam flaking, micronizing, and other processes. This article summarizes the use of different extrusion methods to process different sorghums. the individual s immune system responds by attacking the small intestine and inhibiting the absorption of important nutrients. CD is associated with other autoimmune disorders. Undiagnosed and untreated, it may lead to osteoporosis, infertility, neurological conditions, and in rare cases even cancer. Dermatitis herpetiformis (DH) is an itchy, blistering skin condition that is a form of CD. Many people with DH have no digestive symptoms and only about 40% of them have the positive blood tests (serology) for CD. However, they almost always have the same intestinal damage as people with CD (5). Therefore, persons with CD must adhere to a gluten-free diet. This diet involves strictly avoiding wheat, barley, and rye. Oats are okay but often are contaminated with wheat, barley, or rye. Thus, celiacs must consume foods made from rice, corn, sorghum, millet, teff, amaranth, fonio, buckwheat, and quinoa. Most mainstream breads and many ready-to-eat (RTE) breakfast cereals are wheat based or composed of other glutencontaining ingredients. Therefore, celiacs must use gluten-free substitutes for these foods. The Sorghum Solution Sorghum is growing in popularity because of its bland flavor, lower cost than most gluten-free ingredients, and increasing availability. Sorghum is quite similar to maize or corn but the white food sorghum does not have a strong flavor of its own. Thus, it blends into various products without destroying the taste of other ingredients. That is why it is growing in popularity in Central America as a substitute for corn and wheat flours in producing baked products. A large number of gluten-free products have been made with combinations of sorghum and other acceptable gluten-free cereals. These products usually use tapioca and/or potato starches. Sorghum does not affect taste and provides acceptable starch that interacts with the tuber starches and hydrocolloids to produce relatively good breads. Significant increased interest in sorghum for special food production has encouraged the production of more and betterquality sorghum flours. The cost should be reduced with larger demands for it. Sorghum flours vary in color depending on the type of sorghum grown and processed. Usually sorghum is decorticated to remove the bran and part of the germ. This operation is done with a rice pearler or other abrasive mill. The decorticated kernels can be ground to various sizes and extruded into a wide variety of products depending on flavors and other coatings. Ground, whole-grain, white sorghum produces excellent products. Extrusion of sorghum can be done with friction-type, short-barrel, single-screw extruders to produce snacks similar to corn curls and other expanded shapes and sizes. The color and taste of the extrudates from white sorghum are white and bland which promote their use in a wide variety of simple snacks that can be baked or fried and flavored. They compete with ingredients like corn meal, rice meal, and other materi- CEREAL FOODS WORLD / 285

2 als. For example, the bland flavor and white color of the sorghum works well for the production of potato-based products that require additives to improve flowability and expansion without interfering with the potato flavor. In this application, sorghum works well and could lower costs. Sorghum grains are round, and made up of pericarp, endosperm, and germ. Sorghum is unique in that it is the only cereal grain to have starch granules present in the pericarp (11). The starches and sugars in sorghum are released more slowly than in other cereals and hence it could be beneficial to diabetics (14). Some special sorghums, such as black, tannin, yellow, and others, have outstandingly high levels of phytochemicals that are unique in terms of their healthy components, which include high levels of rare 3-deoxy anthocyanins, flavanoids, condensed tannins, and various other combinations (6,13). The sorghum phytochemicals inhibit tumor development and show high antioxidant activity against different free radicals in vitro and have benefits similar to fruits and vegetables (3,6). Sorghum varieties have been subdivided into three groups (4). Sorghum (white) in group one does not have pigmented testa, but contains a low level of phenols and no tannins. Sorghums in group two have a pigmented testa with tannins, while hightannin sorghum has tannins in the pericarp and the pigmented testa (3,9,13). Since these phenolic compounds are located mainly in the pericarp and testa layers, they can be concentrated into bran fractions with high levels of antioxidants. Extrusion of the whole and wholeground sorghum grains produces an array of different snacks and RTE breakfast foods. Extrudates of these sorghums have a strong, dark brown, highly desirable color that may be used to reduce levels of cocoa. The sorghum phenolics are chemically very similar to those of cocoa. On the other hand, white sorghum can be ground and extruded which makes a great whole-grain snack. If it is ground, it can be used as porridge. Tannins in sorghum are widely reported to reduce caloric availability and hence weight gain in animals. This property is potentially useful in helping reduce obesity in humans and may help with type 2 diabetes. Sorghum phytochemicals also promote cardiovascular health in animals (3,12). The acquisition of sorghum for processing can be challenging but it is becoming more available because of its good properties. Around the world, sorghum is used extensively for foods, including instant or precooked porridges, pasta products, snacks, nonalcoholic and alcoholic beverages, porridges, cous cous, traditional opaque beer, clear beer or lager beer, and many others. In the United States, two different companies brew sorghum-based beer for celiac consumption. The Japanese food industry has successfully used modest amounts of white sorghum in a wide variety of snacks and other foods. The Cereal Quality Laboratory and Food Protein R&D Center, Texas A&M University, has developed a large number of extruded RTE breakfast cereals and snacks from sorghum that are gluten free. The utilization of different sorghums produces better gluten-free, whole-grain products with unique phytochemicals that consumers desire. The objective of this article is to summarize some of the work done to develop gluten-free, whole-grain, high-fiber breakfast cereals and snacks by using three (white, high tannin, and black) types of sorghums alone or in combination with other gluten-free ingredients. The effects of different processing conditions, extruders, and the type of sorghum used on physical and chemical properties were investigated. The extrusion of sorghum has been done efficiently using twin-screw, single-screw, and short-barrel, frictiontype, simple extruders that produce expanded products rapidly at relatively low costs. Sorghum Extrusion Using a Short-Barrel, Friction-Type Extruder Sorghum is normally decorticated to separate the outer layers from the starchrich endosperm. The layers removed are the pericarp, testa, aleurone layer, and Fig. 1. Appearance of raw materials (with different decortication levels) used in singlescrew, short-barrel extrusion. germ. Decortication affects composition and consequently affects processing characteristics. The objective of this study was to evaluate the effects of decortication level and particle size on the characteristics of extrudates obtained by direct-expansion extrusion of white food-type sorghum. Sorghum was decorticated in a mini-dehuller (Nutana Machine Co., Saskatoon, Canada) to remove 10, 20, and 30% of the original weight (Fig. 1). Whole grains at the three different levels of decortication were milled in a hammer mill (Fitzpatrick Hammer Mill D; Fitzpatrick Co., Chicago, IL, U.S.A.) through a no. 10 U.S. Standard mesh. The samples were sieved using no. 20 and no. 50 U.S. Standard sieves. The overs of the no. 20 Standard mesh were considered coarse; the 50 U.S. Standard sieves (meal) were retained and the fines discarded. All samples were tempered to 14% moisture and equilibrated for 24 h at ambient temperature. Yellow corn meal and polished long-grain rice were used as controls. The samples were extruded using a single-screw, friction-type extruder (model MX-3001; Maddox Inc., Dallas, TX, U.S.A.) (Fig. 2). The extrusion was performed at 300 rpm screw speed, and the barrel temperature varied according to the friction that each sample generated. Each sample was extruded until steady-state was reached. All of the samples were baked in a tray oven at 100 C for 30 min, cooled, and packed for further analysis, including the measurement of bulk density, expansion ratio, compression force required to break extrudates, color of extrudates, and water absorption index (WAI). Fig. 2. Short-barrel, single-screw, friction-type extruder. 286 / NOVEMBER-DECEMBER 2010, VOL. 55, NO. 6

3 Extrudate expansion ratio increased and bulk density decreased as the decortication level increased. The expansion ratio was the highest (including corn meal and ricemeal) for 20%-coarse decorticated sorghum (Table I). The expansion ratio of extrudates was higher for coarse particles compared with those of whole and meal sizes, regardless of the decortication level. The bulk density of extrudates was significantly lower for coarse particle-size extrudates compared with those made from whole grain and meal which were not different from each other. However, some of the sorghum extrudates expanded more than either rice or corn samples with similar bulk densities and texture characteristics. Rice extrudates were whiter, followed by sorghum and corn. The removal of the pericarp, testa, aleurone layer, and germ (and consequently the reduction of protein, bran, and oil) allowed starch to produce more and larger bubbles. Thus, higher expansion was obtained as the decortication level increased. However, Fig. 3. Sorghum extrudates with different levels of decortication and particle size compared with corn and rice extrudates. whole sorghum without decortication and/ or milling produced extrudates with adequate expansion. The color of the extrudates was whiter as the decortication level increased as measured by L values and decreasing chroma (Fig. 3). This is a consequence of the removal of the pericarp and germ. The extrudates made from coarse sorghum particles expanded more and in general had more desirable characteristics than those made from whole and meal particles. The removal of the softer endosperm pieces allowed coarse particles to expand better in the extruder. The coarse particle size gave crunchier, softer extrudates with a higher number of force peaks and less area to break than whole and meal particles. However, the difference between the coarse- and whole particle-size extrudates was less when the decortication level increased because of partial removal of soft endosperm (Table I). The coarse particles (pieces of hard endosperm) required more energy for extrusion than the soft endosperm pieces in the whole and meal samples. The removal of the soft endosperm apparently improved the extrusion process and products with better characteristics were obtained. Rice extrudates had acceptable expansion, bland flavor, and a white color. In general, sorghum extrudates made from raw material similar to corn meal (coarse particle size) were whiter, bland flavored, and expanded more than either corn or rice. These properties make white sorghum a feasible option for extrusion. White sorghum can be successfully extruded into snacks with characteristics similar to those made from corn and rice. White sorghum extrudates were highly expanded, crunchy, and light colored with a bland flavor. The white sorghum kernels can be extruded without milling and/or decorticating, enabling the possibility of reduced time, energy, and equipment costs. The benefits of wholegrain utilization (fiber, antioxidants, protein) would be in the extruded product. Sorghum Extrusion Using a Single-Screw, Wet Extruder In a trial, three sorghum varieties (white, tan, and nonwaxy hybrids) were cleaned and decorticated in an abrasive mill until 15% of the original kernel weight was removed (8). The decorticated sorghum was then ground into meal using a Fitzmill (Fitzpatrick Hammer Mill D; Fitzpatrick Co., Chicago, IL, U.S.A.) equipped with a 0.3-mm-mesh screen. Meals from decorticated, ground sorghum were extruded in a 4.5-in expanderextruder cooker (Anderson International Corp., Strongsville, OH, U.S.A.). A mm round short-land die was used for extruding the meal. The meal feed rate was 3 kg/min; a variable water flow rate was used to vary the moisture content of the feed from 17 to 45%. The extrusion temperature was approximately 150 C. The screw speed was 800 rpm. Extruded samples were dried in a forced air oven at 50 C for 24 h, ground in an Udy Cyclone Sample Mill (Udy Corporation, Fort Collins, CO, U.S.A) and sieved through a 60-mesh screen (250 microns). The three sorghums had similar composition except for amylose contents. Decreasing the moisture content during extrusion resulted in an increased expansion and decreased bulk density and breaking strength of the extrudates. Expansion ratio showed a minimum value, while density and breaking strength showed maximum values at 44 45% extrusion moisture content. Moisture content of the resulting extrudates was 17 20%, which contributed to compact, hard products. The sorghum s endosperm type affected expansion, density, and breaking strength of extrudates at all moisture content levels. Table I. Properties of extrudates from whole and decorticated white food sorghums decorticated at 0, 10, 20, and 30% z Treatment Expansion Bulk Density Peaks Viscosity Water Absorption (decorticated/particle) Ratio (g/ml) (#) L Chroma (cp) Index 0% whole 3.32 j a 40.7 f 78.9 g 15.2 b 277 g 5.68 h 0% coarse 4.41 g de 51.1 de 81.1 f 15.3 b 328 cd 6.19 ed 0% meal 3.17 k a 33.1 g 75.5 h 15.3 b 261 h 5.75 hg 10% whole 4.20 h bc 50.2 de 82.5 ef 14.7 c 294 f 5.93 gf 10% coarse 4.86 bc g 53.2 de 84.9 bcd 13.9 ef 334 c 6.06 ef 10% meal 4.00 i c 48.7 e 82.6 ef 14.4 cd 295 f 6.05 ef 20% whole 4.56 ef fg 62.2 ab 83.6 de 14.5 c 308 e 6.46 bc 20% coarse 5.04 a cd 54.5 cde 85.9 abc 13.8 ef 367 a 6.48 bc 20% meal 4.41 g ef 52.4 de 83.8 de 14.1 de 333 cd 6.25 cde 30% whole 4.75 cd cd 60.7 abc 84.7 cd 12.9 g 323 d 6.54 b 30% coarse 4.92 ab ef 54.7 cde 86.3 ab 13.7 f 365 a 6.91 a 30% meal 4.67 de ef 56.0 bcd 84.5 cd 13.6 f 353 b 6.52 b Corn meal 4.78 cd ef 65.7 a 84.6 cd 34.4 a 279 g 5.68 h Rice milled 4.55 f b 65.1 a 87.4 a 10.8 h 346 b 6.37 bcd z Mean values within a column/row followed by the same letter are not significantly different (P > 0.05). 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4 Nonwaxy sorghum produced the least brittle and most dense extrudates with the least expansion. Light micrographs of extrudates showed that starch granules retained some of their birefringence under high-extrusion moisture conditions. Apparently, the higher water content increased the fluidity (less shear) of the meals in the extrusion channel during extrusion cooking. Scanning electron microscope (SEM) micrographs revealed that waxy endosperm-type sorghums processed at lowextrusion moisture content levels produced the most expanded, lightest appearing extrudates with uniform air cell distribution, small pores, and thin air bubble walls. On the other hand, high extrusion moisture content and higher amylose content (nonwaxy sorghum) yielded the least expanded extrudates, uneven air cell distribution, and coarse air cell walls. These extrudates contained more damaged starch as measured by enzyme-susceptible starch ratio and water solubility. Different amylose-to-amylopectin ratios in the sorghum meal did not affect the in vitro protein digestibility of the extrudates; however, digestibility of extrudates increased as extrusion moisture content decreased. Thin porridges (atoles) with acceptable sensory characteristics were prepared with no additional cooking from extruded sorghum flours. Atoles from extruded, low-amylose sorghums were preferred by the panelists because they had a viscous consistency, smooth texture, slightly roasted flavor, and light color. Thus, the utilization of sorghum with lower amylose contents (waxy varieties) is feasible for the production of snacks, breakfast cereals, and beverages. Malleshi et al. extruded sorghum flour (60%) with toasted mung bean flour (30%) and nonfat dry milk (10%) by using a Brabender single-screw extruder to make precooked RTE weaning foods (10). The soluble dietary fiber increased about 19% in the sorghum food, and in vitro protein digestibility of the sorghum blend was enhanced by extrusion. This indicated that extrusion of sorghum, blended with mung bean flour and nonfat dried milk, was an excellent way to prepare nutritious RTE weaning and supplementary foods with desirable chemical and nutritional properties. Sorghum Extrusion Using a Twin-Screw Extruder Breakfast cereals and snacks were developed by using whole-ground white, high-tannin, and black sorghums (Fig. 4). Other ingredients used in the formula were corn flour, rice flour, soy isolates, sugar, and salt. All three types of sorghum and other ingredients were ground using a hammer mill (Fitzpatrick Hammer Mill D; Fitzpatrick Co., Chicago, IL, U.S.A.) fitted with a in. (69-micron) screen. Whole-ground sorghum (80%) and other ingredients (20%) were mixed according to formula in a ribbon blender for 10 min and stored at room temperature for 12 h (Table II). A twin-screw extruder (Wenger TX 52; Wenger Manufacturing Inc., Sabetha, KS, U.S.A.) was used to extrude the sorghums. Processing conditions of the extruder are given in Table III. After drying (Wenger series 4800 gas-fired dryer; Wenger Manufacturing Inc.) at 105 C for 5 min., the extrudates (Fig. 5) were analyzed for bulk density, expansion ratio, compression force, and antioxidant activity. Proximate composition of wholeground sorghum extrudates indicated that high-tannin sorghum had the highest level of dietary fiber (11.1%) while the protein contents were 12.0% (Table IV). Black sorghum contained 9.8% dietary fiber but protein (15.5%) was higher than that of high-tannin sorghum extrudates. White Fig. 4. Whole grains of high-tannin, black, and white sorghums. Fig. 5. Extrudates with different types of sorghum. sorghum contained the least amount of dietary fiber (6.3%) and protein (10.4%). There was a significant (P < 0.05) difference in the bulk density of corn and sorghum extrudates (Table V). Black sorghum extrudates had the highest bulk density in sorghum extrudates while the bulk densities of white and high-tannin sorghum extrudates were similar. The composition of corn flour is predominately starch, which produces extrudates with larger air cells. On the other hand, wholeground, high-tannin sorghum contained more dietary fiber (Table IV) which should have increased the bulk density of hightannin sorghum extrudates. We can t explain why the whole-ground, high-tannin sorghum extrudates had bulk density similar to the white sorghum extrudates which had significantly less fiber. However, the bulk density for whole white sorghum extrudates decreased with increased decortication up to 20% (1). Decortication removes the bran fraction of sorghum; therefore, the starch contents are increased which increases expansion with decreased Table II. Formulations used in twin-screw extrusion Ingredients Percent (%) Corn flour 85 Rice flour 6 Soy isolates 5 Sugar 3 Salt 1 Table III. Extrusion parameters and operating conditions of the twin-screw extruder Parameters Conditions Feed screw speed (rpm) 11 Pre-conditioner speed (rpm) 306 Extruder screw speed (rpm) 310 Water flow to extruder (kg/h) 4.1 Die diameter (mm) 3.0 Barrel temperature zone 1 50/39 Barrel temperature zone 2 75/74 Barrel temperature zone 3 75/75 Barrel temperature zone 4 75/75 Barrel temperature zone 5 95/120 Barrel temperature zone 6 110/111 Table IV. Percent (dry weight basis) proximate analysis and dietary fiber levels of different types of whole-ground sorghum a Protein Sample Moisture N (6.25) b Lipids Ash Dietary Fiber Crude Fiber White sorghum High-tannin sorghum Black sorghum a Source: Turner (15). b N: 6.25, conversion factor for feed stuff. 288 / NOVEMBER-DECEMBER 2010, VOL. 55, NO. 6

5 bulk density of extrudates (1). There was a significant (P < 0.05) difference in the expansion ratio of all extrudates. The expansion ratio of black sorghum extrudates was lower than that of white and high-tannin sorghum extrudates (Table V). The expansion ratio of corn extrudates fell in between the sorghum extrudates. The black sorghum s thick pericarp and soft endosperm may be characteristics that adversely affect expansion. Turner found that the expansion of whole-unground and cracked black sorghum was lower than sorghum and corn meals (15). The expansion Table V. Mean bulk density, expansion ratio, and compression force of twin-screw extrudates z Expansion Samples Bulk Density (kg/l) Ratio Compression Force (Newton) Corn flour extrudates b 3.64 b - White, whole- ground sorghum extrudates a 3.86 d 45.2 a High-tannin, whole-ground sorghum extrudates a 3.78 c 53.1 b Black, whole-ground sorghum extrudates a 3.41 a 42.9 a z Source, D. L. Turner (15). Mean values within a column/row followed by the same letter are not significantly different (P > 0.05). Table VI. Phytochemicals in white, black, and high-tannin sorghum whole raw grains a Anthocyanins Antioxidant Activity Phenols Tannins (mg of Sorghum Type (µmol of TE/g) (mg/g) (mg of CE/g) luteolinidine/g) White High tannin Black a Source: Awika and Rooney (3). TE measures antioxidant strength based on Trolox and is measured in Trolox Equivalents (TE), e.g., micromolte/g. CE measures antioxidant strength based on Catechin and is measured in Catechin Equivalents (CE), e.g., mg CE/g. Fig. 6. Antioxidant activity of different types of sorghum before and after extrusion. of tannin and black sorghum extrudates decreased with increased bran fortification (15). Black sorghum bran-fortified extrudates expanded significantly less than tannin bran extrudates. But all this was based on a single-screw, short-barrel, frictiontype extruder (Maddox Inc.). The breaking force needed to rupture and break high-tannin sorghum extrudates (Table V) was higher than the force needed to break white sorghum and black sorghum extrudates. Black sorghum extrudates take less force to rupture and break than white and high-tannin sorghum extrudates. Again, floury starch of black sorghum could be a contributing factor. High-tannin sorghum extrudates were significantly harder to break than the others. Breakfast cereals may have a high level of crispness but after a designated time in milk they lose crispness. The bowl life of extrudates made with corn and different sorghums varied but were low and unacceptable. Therefore, in another trial, breakfast cereals were prepared with a twin-screw extruder using whole-ground white sorghum and 5 10% high-tannin sorghum bran (2). In this trial, the bowl life of breakfast cereals was increased up to 18 min. Sorghum grains contain phytochemicals, including antioxidants, flavanoids, phenols, tannins, and anthocyanins (Table VI) (3). These phenols have antioxidant properties that may protect against disease. All three sorghums had significant antioxidant activity after extrusion (Fig. 5). Maximum antioxidant activity ( µmol of trolox equivalents [TE]/g) was measured in high-tannin sorghum mix before extrusion. After extrusion it was reduced to µmol of TE/g. The difference in antioxidant activity of white and black sorghum extrudates was not significant. The extruded hightannin and black sorghum had 73 and 85% retention of antioxidant activity after extrusion, respectively. This higher retention in antioxidant activity may be caused by phenolics in the cell wall being solubilized and thus available for analysis. The cleavage and re-association of phenols could occur as well (3). Thus, the antioxidant activity in the extrudates depends largely on the antioxidant activities of raw material. The extrudates of high-tannin and black sorghums retain most of the antioxidants in the finished products. Different types of extruders can be used for the development of gluten-free breakfast cereals and snacks. The type of extruder depends upon the desired final product and initial investment. Dry extruders require relatively low capital investment to produce direct expanded sorghum snacks with different levels of decortication. Decorticated white sorghum can be used to produce snacks comparable to corn meal snacks. A short-barrel, friction-type extruder is a good choice where steam is not available. Dry extruders are able to grind whole sorghum during extrusion, and therefore grinding steps can be eliminated. The final size of the product may be limited to certain sizes, as the high pressure involved with this type of extruder makes it extremely difficult to shape a product that is less than 2 mm. Sorghum cereals and snacks can be pre- CEREAL FOODS WORLD / 289

6 pared using sorghum with other cereals and ingredients by using a single-screw wet extruder. These extruders are easy to operate and cost more than the dry extruder but are about half the price of twin-screw extruders. Single-screw wet extruders yield superior shaped products compared with dry extruders because of better process control. Twin-screw extruders can be used to develop versatile breakfast cereals and snacks by using sorghum with high levels of bran and additional ingredients. These can handle a wide range of particle sizes of formula ingredients. Very finely ground sorghum and bran can be fed directly into the twinscrew extruder, as well as very coarse ground sorghum with other ingredients. References 1. Acosta-Sanchez, D. White food-type sorghum in direct expansion extrusion applications. M.S. degree thesis. Texas A&M University, College Station, TX, U.S.A., Asif, M., Rooney, L.W., Riaz, M. N., and Mack, C. A. Gluten-free, high-fiber, sorghumbased breakfast cereal. Presented at the Great Plains Sorghum Conference, Amarillo, TX, U.S.A., Unpublished. 3. Awika, J. M., and Rooney L. W. Sorghum phytochemicals and their potential impact on human health. Phytochemistry 65:1199, Butler, L. G., and Price, M. L. Tannin biochemistry progress report in: Annual Inheritance and Improvement of Protein Quality and Content in Sorghum, Report 13. Purdue University, West Lafayette, IN, U.S.A., Celiac Disease Center, The University of Chicago. Celiac disease 101: Overview. Published online at 6. Dykes, L., and Rooney, L. Sorghum and millet phenols and antioxidants. J. Cereal Sci. 44:236, Gallagher, E. Gluten-Free Food Science and Technology. Wiley Blackwell Publishers, United Kingdom, Gomez, M. H., Waniska, R. D., Rooney, L. W., and Lusas, E. W. Extrusion cooking of sorghum containing different amounts of amylose. J. Food Sci. 53:6, Hahn, D. H., and Rooney, L. W. Effect of genotype on tannins and phenols of sorghum. Cereal Chem. 63:4, Malleshi, N. G., Hadimani, N. A., Chinnaswamy, R., and Klopfenstein, C. F. Physical and nutritional qualities of extruded weaning foods containing sorghum, pearl millet or finger millet blended with mung beans and nonfat dried milk. Plant Food Hum. Nutr. 49:181, Rooney, L. W., and Serna-Saldivar, S. Handbook of Cereal Science and Technology, 2nd ed. Marcel Dekker, New York, NY, U.S.A., Rooney, T. K., Rooney, L. W., and Lupton, J. R. Physiological characteristics of sorghum and millet brans in the rat model. Cereal Foods World 37:782, Shahidi, F., and Naczk, M. Phenolics in Food and Nutraceuticals. CRC Press New York, NY, U.S.A., Toomey, G. Sorghum as Substitute: Food Enterprises for Indian women. Published online at bitstream/10625/25606/1/ pdf. IDRC Reports, Turner, D. L. The use of specialty sorghums for expanded snacks food processing. M.S. degree thesis. Texas A&M University, College Station, TX, U.S.A., A Siemer ad appeared here in the printed version of the journal. 290 / NOVEMBER-DECEMBER 2010, VOL. 55, NO. 6

7 Muhammad Asif is a doctoral candidate and research and teaching assistant at the Food Protein R&D Center and Cereal Quality Lab, Texas A&M University. Asif is currently conducting extrusion and food sorghum phenolic compound research focusing on starch digestibility and antioxidant properties of gluten-free, high-fiber breakfast cereals and snacks. AACC Intl. member Asif can be reached at asif@tamu.edu. Lloyd W. Rooney, a regents professor and faculty fellow, Cereal Quality Lab, Soil & Crop Sciences Department, Texas A&M University, teaches cereal technology/chemistry and related courses. He participates in post-harvest technology and research and development programs all over the world focusing on corn, wheat, and sorghum processing quality. His research has resulted in numerous wheat cultivars and sorghum hybrids. The Snack Food Processing coeditor has more than 300 publications on cereal processing, chemistry, quality, and nutrition. AACC Intl. member Rooney can be reached at lrooney@tamu.edu. David Acosta-Sanchez is a product development scientist, with Kellogg Company s Global Snacks Division since Prior to that, he worked with Grupo Gamesa-Quaker (Pepsico) in Monterrey, Mexico. His B.S. degree is in food engineering from Monterrey Tech-ITESM, Monterrey, Mexico. His M.S. degree is in food science and technology from Texas A&M University. AACC Intl. member Acosta-Sanchez can be reached at david.acosta@kellogg.com. Christopher A. Mack received his Bachelor of Science in agricultural engineering from Texas A&M University. He has worked at the Food Protein R&D Center since 2005 and is the research associate for the Extrusion Technology Program. He can be reached at chrismack@tamu.edu. Publish with AACC International Contribute to the development of scientific learning by publishing your cutting-edge grain science research or new technology development in one of AACC International s publications or at the annual meeting. AACC International offers members a variety of publishing formats. ttt Annual Meeting The 2011 Annual Meeting will take place October in Palm Springs, CA, U.S.A. Abstract submission for oral presentations and posters will open March 1. ttt Cereal Chemistry This international journal publishes scientific papers reporting significant, recent research. Papers may be comprehensive reviews or reports of original investigations in biochemistry, biotechnology, products, processes, and analytical procedures associated with grain crops. Mian N. Riaz is the director of the Food Protein R&D Center, head of the Extrusion Technology Program, and a graduate faculty in the Food Science and Technology Program at Texas A&M University. He published four books, 14 chapters, and more than 100 papers on extrusion and other related topics. AACC Intl. member Riaz can be reached at mnriaz@tamu.edu. ttt Cereal Foods World CFW covers grain-based food science, technology, and new product development. Four types of articles are published: features, perspectives, technical reviews, and reports. Find out more at CEREAL FOODS WORLD / 291