- Rooney, Lloyd
- Texas A&M University
- Start date
- End date
- To characterize quality attributes and develop systems to measure quality of cereals, oilseeds, and bioprocess co-products
- To develop methods to maintain quality, capture value, and preserve food safety at key points in the harvest to end product value chain
- To quantify and disseminate the impact of market-chain technologies on providing high value, food-safe, and bio-secure grains for global markets and bioprocess industries.
- More information
- NON-TECHNICAL SUMMARY: A team of scientists will improve the quality attributes of wheat and sorghum for use in tortilla, bread and nutraceuticals, respectively. Sorghums with high levels of antioxidants and unique levels of rare 3-deoxyanthocytanins, flavanones and flavones will be used to determine their potential in healthy foods. Condensed tannins of sorghums will be evaluated for their potential to produce foods with reduced digestibility of starches. Selected corn cultivars will be analyzed for phytochemicals. New surface reflectance methods if successful could immediately increase the efficiency of analysis of grains for quality attributes. Additional information on effective methods of following grains of different lots through the marketing channels could be useful in case of contaminated lots of grain mixed into market channels.
APPROACH: The quality attributes of sorghum and wheat will be emphasized by working with breeding programs to identify new cultivars with improved quality attributes for bread and tortilla production. Work to confirm that sorghum cultivars have excellent levels of rare flavanoids will be expanded to produce healthy sorghums for use in special foods. In vitro methods to evaluate anti-inflammatory properties of these sorghums will be used to document those properties. Some sorghums have condensed tannins that have high antioxidant activities and complex with proteins and starches to reduce the rate of digestion of those cultivars. New methods to analyze grain using reflectance methods will be applied to an array of sorghum and other grains with differing composition. This exploratory work will use existing samples of grain with different composition of flavanoids and other components. These efforts will work closely with crop improvement programs. New techniques to use markers to follow what happens to grain during marketing will be evaluated along with other methods of grain analysis.
PROGRESS: 2007/01 TO 2007/12
OUTPUTS: New special black sorghums with and without pigmented testa vary in tannin content and in the relative levels of luteolinidin and apigeninidins. Certain hybrids have high levels of luteolinidin or apigeninidins which was confirmed by comparison of grains grown at several locations. Thus, special sorghums with high levels of unique anthocyanins with or without condensed tannins can be produced to optimize health benefits and improve functionality in colored foods. The pigments are stable over a large pH range which is a significant advantage over other natural plant pigments. Grain yields of black sorghum hybrids are high, and grain is easily decorticated to concentrate the pigments. We have found significantly large quantities of flavones and flavonone in some sorghum varieties which were significantly higher than other sources of the compound when sorghums were grown in several environments. Extracts of some of them have significantly inhibited in-vitro human colon and breast cancer cells. In cooperative trials, rats fed tannin and black sorghum brans had significantly less colon cancer cells than those fed cellulose or white sorghum brans. Rats and swine fed sorghum tannin bran had significantly higher levels of metabolic products from tannins than those that did not consume tannin sorghum bran suggesting that they are being partially digested. The quantity of anthocyanins and tannins of sorghum are affected by variety, environment and interaction of environment. Several products containing bran from black and tannin sorghums had excellent flavor and color with high levels of antioxidants and dietary fiber. Significant reduction in measurable antioxidant activity occurs when grain is processed because of interactions among the tannins, proteins and carbohydrates. In addition, the high-tannin and black sorghum porridges were more slowly digested using in-vitro assays that estimated the glycemic index. Some processes such as high-friction extrusion may depolymerize the condensed tannins. The potential for use of whole-grain specialty sorghums in foods is excellent because they provide significant nutritional and functional benefits with a healthy, natural, dark color and whole-grain taste. Wheat samples from the breeding program are evaluated for milling and baking properties. Evaluation of wheat lines for tortilla quality continues. New wheat cultivars with improved quality have been released from the breeding program. Six MS and two PhD students graduated this year with theses related to sorghum quality and tortilla properties. They have positions in the food industry.
PARTICIPANTS: numerous food science graduate students; food industry; TAES sorghum, corn and wheat breeders/agronomists
TARGET AUDIENCES: nutraceutical companies, healthy food products, grain marketing
PROJECT MODIFICATIONS: Dr. Betran moved. Dr. Waniska, deceased.
IMPACT: 2007/01 TO 2007/12
There is increasing interest in use of special sorghums in healthy foods. Improved understanding of the unique anthocyanins and flavonoids in different genotypes of sorghum should soon lead to new products containing sorghum or its extracts for use in nutraceuticals and natural coloring agents. Sorghums developed in the TAMU sorghum improvement program are used commercially to provide identity-preserved grain for a wide variety of human and animal foods.
PROGRESS: 2006/01/01 TO 2006/12/31
Red, lemon-yellow and white pericarp sorghums without pigmented testa vary significantly in different anthocyanins and related compounds. Extracts of some of them have significantly inhibited in-vitro human colon and breast cancer cells. In cooperative trials, rats fed tannin and black sorghum brans had significantly less colon cancer cells than those fed cellulose or white sorghum brans. Rats and swine fed sorghum tannin bran had significantly higher levels of metabolic products from tannins than rats that did not consume tannin sorghum bran. Additional experiments have confirmed that tannin sorghum bran is an effective antioxidant in cooked, ground-meat patties. New special black sorghums containing pigmented testa vary in tannin content and in the relative levels of luteolinidin and apigeninidins. These data, if confirmed, indicate that special sorghums with high levels of unique anthocyanins, plus condensed tannins, might be produced to optimize health benefits and improve functionality in colored foods. The yields of black sorghum hybrids are high and produce large quantities of storable pigments. Comparison of tannins, total phenols and antioxidants among different cereal grains clearly demonstrated that special sorghums have significantly higher antioxidant levels than other cereals. The quantity of anthocyanins and tannins of sorghum are affected by variety, environment and interaction of environment and variety. Mold attack during and after maturation produces phytoalexins which increased the level of anthocyanins significantly. Several products containing bran from white, black and tannin sorghums had excellent flavor and color with high levels of antioxidants and dietary fiber. Significant reduction in measurable antioxidant activity occurs when grain is processed, probably because of interactions among the tannins, proteins and carbohydrates. In addition, the high-tannin sorghum extrudates and porridges were more slowly digested using in-vitro assays that estimated the glycemic index. Some processes such as high-friction extrusion may depolymerize the condensed tannins. Commercial mixes for gluten-free breads containing white sorghum flour are increasing. The sorghum-based celiac foods are preferred over other nongluten bread mixes. Identity preserved white, tan plant sorghum grain continue to be marketed in Japan in snacks, baked goods and other products. The bland flavor of the white sorghum has a unique advantage for oriental snacks and competes with rice. The potential for use of whole-grain specialty sorghums in foods is excellent because they provide significant nutritional and functional benefits with a healthy, natural, dark color and whole-grain taste.
IMPACT: 2006/01/01 TO 2006/12/31
Sorghums developed in the TAMU sorghum improvement program continue to be used commercially to provide identity preserved grain for a wide variety of human and animal foods. There is increasing interest in use of special sorghums in healthy foods. Sorghum is used in processed, high-value foods for sophisticated markets, i.e., gluten-free products, natural, dark-colored whole-grain products with high dietary fiber and increased antioxidant levels. Sorghum use in processed foods and beverages is increasing. A major US brewer is using sorghum in gluten-free beer; South Africa and other breweries in Africa use white, identity-preserved sorghum in commercial, malt-free, lager beer. Improved understanding of the unique anthocyanins and other phenols in different genotypes of sorghum should lead to new products containing sorghum grain or extracts of it for use in nutraceuticals and natural coloring agents.
PROGRESS: 2005/01/01 TO 2005/12/31
Sorghum tannins are misunderstood around the world and negatively affect sorghum marketability. A bulletin, Myths about Tannins in Sorghum, was written and translated into Spanish and French. In simple terms, it clarifies the current state of knowledge about sorghum tannins. The extrusion of tannin sorghums into tasty, whole-grain snacks with high antioxidant levels was demonstrated. High-tannin sorghum extrudates and porridges were more slowly digested using in-vitro assays that produce estimated glycemic indexes. Significant reduction in measurable antioxidant activity occurs when grain is processed, probably because of interactions among the tannins, proteins and carbohydrates. HPLC analysis clarifies that types of sorghum without a pigmented testa do not have condensed tannins. There are small amounts of materials that give positive tests for phenols in all cereals, but they are not tannins. The anthocyanins of sorghum vary depending upon the genetics of the kernel. Mold attack during and after maturation increases the level of anthocyanins. Special sorghums with high levels of phenolics and excellent health benefits were found, but must be confirmed by additional testing. Several products containing bran from white, black and tannin sorghums had excellent flavor and color; they also provide high levels of antioxidants and dietary fiber. Additional tests confirmed that sorghum antioxidants are effective in preserving the shelf life of raw and precooked, stored, ground beef patties. Extruded tannin sorghum and flax seed hulls produced expanded snacks with good taste and improved levels of antioxidants. Commercial mixes for gluten-free breads containing white sorghum flour continue to increase. Sorghum-based foods for celiacs are often preferred over other nongluten bread mixes. White, tan plant sorghum hybrids continue to be identity-preserved and marketed in Japan where a large number of snacks, baked and related products are produced. Additional extrusion experiments confirm that cracked or coarsely ground whole grain white sorghum makes excellent snacks when a short-barrel friction extruder is used. The bland flavor of the white sorghum gives a unique character to snacks. The potential for use of whole grain specialty sorghums in foods is excellent because they can provide significant nutritional and functional benefits. Staling of corn tortillas is reduced by optimum blends of amylases, guar gum, CMC, and in some cases, soy flour. The tortillas are fluffier and give consumers the impression that they are softer. Proper warming of the tortillas, in some cases, eliminates the advantage. Corn tortillas containing black and tannin sorghum bran had significantly more acceptable properties when the additives were used.
IMPACT: 2005/01/01 TO 2005/12/31
Sorghums developed in the TAMU sorghum improvement program continue to be used commercially to provide identity-preserved grain for a wide variety of human and pet foods. Special sorghums with high levels of antioxidants exceeding blueberries have significant potential for health food. The concepts determined in the project over the years have proven acceptable to many food processors around the world, and sorghum is beginning to find its way into processed high-value foods for sophisticated markets, i.e., gluten-free products, natural dark-colored whole grain products. This is because of the multidisciplinary nature of this project which involves significant contributions from sorghum breeders and others.
PROGRESS: 2004/01/01 TO 2004/12/31
Two advanced wheat lines are in process of formal release to producers. More than two thousand wheat samples were analyzed prior to planting to enable selection for quality attributes. Single kernel hardness was used as the first preliminary screen followed by protein and mixograph properties. Several blue and red corns have excellent processing properties. There were differences in cooking time, pericarp removal and other properties. The new corns may produce deep red alkaline cooked products. Use of soy flour, guar gum, CMC and maltogenic amylases significantly improved texture of corn tortillas stored at room temperature and refrigeration. Soy flour addition improved the nutritional and anti-staling properties of corn tortillas. Sorghum anti-oxidants are effective in preserving the shelf life of ground beef patties. A patent disclosure was made describing the use of finely ground bran from special sorghums to preserve meat patties without adversely affecting the color or flavor. In addition, VITABREAD, a composite mix for bread machines with natural dark color, high levels of soluble and insoluble dietary fiber and an excellent flavor was developed. Addition of ground flax increases omega 3 fatty acids and anti-oxidants. Gluten free breads containing sorghum flour, cassava, xanthan and corn starch had good loaf volume and crumb structure compared to commercial mixes. Inulin improved loaf volume and produced high fiber gluten free breads when blended with sorghum flour and ground flax seed. White, tan plant sorghum hybrids continue to be identity preserved and marketed in Japan where a large number of snacks, baked and related products are produced. The PI participated in workshops on white food sorghums in South Africa, Mali, Central America and in a snack food processing short course at TAMU. Additional extrusion experiments confirm that cracked or coarsely ground whole grain white sorghum makes excellent snacks when a short barrel friction extruder is used. The bland flavor of the white sorghum gives a unique character to mild flavors. The whole grain potential is significant because of its nutritional importance. Sorghum tannins are misunderstood around the world and negatively affect its marketing. HPLC analysis of the tannins clarifies that types of sorghum without a pigmented testa do not have condensed tannins. There are small amounts of materials that give positive tests for phenols in all cereals but they are not tannins. The PI participated in workshops to clarify that most sorghums do not have tannins. In addition, those with tannins are consumed by animals, but the feed efficiency is significantly reduced depending upon the animals and methods of processing and feeding the grain.
IMPACT: 2004/01/01 TO 2004/12/31
Sorghums developed in the TAMU sorghum improvement program continue to be used commercially to provide identity preserved grain for a wide variety of human and animal foods. The concepts determined in the project over the years have proven acceptable to many food processors around the world and sorghum is beginning to find its way into processed high value foods for sophisticated markets. This is because of the multidisciplinary nature of this project which involves significant contributions from sorghum breeders and others.
PROGRESS: 2003/01/01 TO 2003/12/31
Three in vitro methods of determining antioxidants in sorghum products indicated that tannin sorghum products were excellent sources of antioxidants equal to that of blueberries and related fruits. The ORAC method was highly, significantly correlated with total phenols, tannin content, ABTS and DPPH of the products. HPLC analysis of the procyanidins and anthocyanins confirmed that sorghums without a pigmented testa are tannin free. Extrusion of tannin sorghums increases the monomers, dimers and trimers, while decreasing the polymers larger than ten that comprise the proanthocyanidins. This indicates that extrusion could improve the absorption. Other processes like baking did not alter the proanthocyanidin polymers in processed foods. Bread containing tannin sorghum bran had dark brown color, excellent taste and good loaf volume when 15% finely ground bran was added. Fine grinding bran improved the color and texture of the bread. Whole white food type sorghums have excellent extrusion properties either as whole kernels or as cracked, ground and decorticated grains. Healthy, whole sorghum snacks were produced in a short barrel low cost friction extruder. The expansion is less and there are pieces of pericarp in the extrudate which is a positive experience for consumers desiring healthy whole grain products. Extrudate expansion, texture, taste and crispiness depends upon the extent of processing to remove the germ and pericarp. Decorticated white sorghum extrudates are lighter in color with a bland flavor that is similar to rice. White sorghums can compete with rice for extrusion applications. More than two thousand wheat samples were analyzed prior to planting to enable selection for quality attributes. Single kernel hardness was used as the first preliminary screen followed by protein and mixograph properties. Quality protein maize properties for alkaline cooking were comparable to standard food corn hybrids. There were differences in cooking time, pericarp removal and other properties but the new QPM corns have excellent cooking properties. Use of guar gum, CMC and maltogenic amylases significantly improved texture of corn tortillas stored for at room temperature and refrigeration. Dry masa and fresh masa tortillas stale differently and anti-staling ingredients behave differently in fresh vs. dry masa tortillas. Amylases must be combined with other hydrocolloids to reduce staling of tortillas.
IMPACT: 2003/01/01 TO 2003/12/31
Sorghum with high levels of tannins contains antioxidant activities equal to or higher than blueberries. The bran obtained by abrasive milling has very high levels of antioxidants and insoluble dietary fiber with an attractive natural brown color. Baked products with high fiber and antioxidant properties can be made from 10-15% bran substitution for wheat flour. Friction type short barreled extruders produce excellent whole grain or bran fortified snacks and breakfast foods. These health foods from special sorghums could expand markets for sorghum. The extrusion process could alter the polymer size of the antioxidants to improve absorption.
PROGRESS: 2002/01/01 TO 2002/12/31
New white and red tan plant hybrids with promising properties were identified in sorghum hybrid trials grown across the sorghum belt. Several new earlier maturity food hybrids are nearing commercial reality. Market development in Asia and Mexico by the US Grains Council with assistance from this project was continued. Whole sorghum snacks were produced by low cost friction extrusion. They have excellent properties and can be flavored with mild to strong seasonings. The hybrids used are derived from ATx631XRTx436 released from TAES several years ago. NIR and single kernel hardness methods were used to evaluate sorghum quality. Calibration equations for starch, protein and moisture from more than 155 whole kernel sorghum samples were developed for a Pertin 7000 DB NIR. Milling evaluation of food type sorghums includes adjustment of the milled product yields to a constant acceptable color. This shows the significant differences among food and feed type sorghums where color makes a significant difference. A mix containing high antioxidant sorghum bran, soluble and insoluble dietary fiber and omega-3 fatty acids from flax seed produced a nutraceutical bread with a natural brown crumb color and excellent taste and texture. The sorghum bran has ORAC values much higher than fruits and berries and can be produced economically. Low levels of barley flour give significant improvement in texture of table tortillas. The beta-glucans of barley have a significant effect on tortilla properties; a concentrate of barley flour containing 70% b-glucans gave positive improvement in tortilla texture. Staling of corn tortillas is reduced by use of specific amylase enzymes in combination with CMC and beta-glucans from barley concentrates. Wheat samples (nearly 2,000) were evaluated for milling and baking quality in collaboration with the wheat improvement program where approximately one new variety has been released annually for the last 30 years. Quality protein maize inbreds were released by the corn improvement program; they have good food processing properties and higher lysine and tryptophan content.
IMPACT: 2002/01/01 TO 2002/12/31
NIR methods to efficiently measure composition of whole kernel sorghum were developed to promote value-added marketing of sorghums. Improved food sorghums are the basis for snacks and other food products being marketed in Japan and the USA. Proto-type foods from sorghum developed in our lab have stimulated interest in domestic and international markets. Farmers could obtain more money for value added crops.
PROGRESS: 2001/01/01 TO 2001/12/31
Several new sorghum snack foods were developed from identity preserved US white sorghum in Japan. Commercial sales in Japan continue to expand. The bland flavor, light color and good expansion properties are an advantage for sorghum mealover rice meal. The extrusion properties of food type sorghums are equal to that of corn and rice. The hybrids used are derived from ATx631XRTx436 released from TAES several years ago. New white and red tan plant sorghum hybrids with promising properties were identified in white tan plant hybrid trials grown across the sorghum belt. Several new earlier maturity food hybrids are nearing commercial reality. Market development in Asia and Mexico was expanded by the Grains Council with assistance from data obtained in this project. NIR and single kernel hardness instruments were used to evaluate sorghum quality. The effect of environment and genetics are critically important. Food sorghums are quite sensitive to weathering and discoloration which means they cannot be grown in some areas. Calibration equations for NIR data from more than 100 whole kernel sorghum samples were developed for a Pertin 7000 instrument. Milling evaluation of food type sorghums include adjustment of the milled product yields to a constant acceptable color. This clearly indicated significant differences among food type sorghums. The Chlorox bleach test for tannin sorghums sometimes gives erroneous results for weathered sorghum. Clear cut standards must be run since weathered kernels bleach into discolored kernel that can be improperly classed as tannin sorghum. Nutraceuticals from tannin and black sorghum brans are promising sources of antioxidants with higher levels than blueberries.The characterizxation of phenols from sorghum grain continues. Bread with high antioxidant, soluble and insoluble dietary fiber and omega -3 fatty acid levels was produced with a bread machine mix containing sorghum bran, gluten, flax, barley and other ingredients. It gives a dark natural color with great taste and texture comparable to variety breads. Tortillas were produced using corn tortilla equipment from 100% barley flours. Barley tortillas have excellent flexibility with a significantly different taste that varies depending upon the variety.Amylose and beta-glucan content of the barley flours significantly affect tortilla properties. Low levels of barley flour give some improvement of texture of corn tortillas which is probably related to increased levels of beta-glucan.Staling of tortillas is quick and a real challenge to control in a cost effective manner. Corn table tortilla texture was not significantly improved by addition of different levels of emulsifiers and shortenings. Enzymes in combination with other additives look promising but may be too costly. Wheat samples were evaluated for milling and baking quality with emphasis on early generation testing.
IMPACT: 2001/01/01 TO 2001/12/31
The acceptance of Japanese snack manufacturers of white food type sorghum meal for commercial snack markets has led to sales of identity preserved food sorghum. The market is currently small but growing and could lead to significant production of sorghums for food processing internationally and domestically.Someproducers could receive premiums for production of sorgum which can be produced under limited irrigation efficiently. The white tan plant sorghums have good production and agronomic properties for some production areas. Better hybrids are in the pipeline.
PROGRESS: 2000/01/01 TO 2000/12/31
NIR calibration equations were developed for whole and ground sorghum for protein, moisture, fat, starch and ash. The correlations were high but more samples representing the typical range in composition are required to improve the calibrations. Brown and black sorghums contain catechins and phenols that have high anti-oxidant values comparable to fruits and vegetables. Bran from brown (tannin)sorghum contained Oxygen Radical Absorption Capacity (ORAC) equal to or greater than blueberries. Bran fractions produced bread and cookies with significantly enhanced anti-oxidants and dietary fiber. Wheat gluten(1%)retarded staling of corn tortillas. Barley flour produced tortillas with excellent texture which related to amylose and beta-glucan content. A high protein corn did not produce tortillas with improved texture. A large number of early generation wheat samples were evaluated for hardness, milling and baking properties. The breeders utilize the information for early generation selection. Tan plant sorghum hybrids were grown in eight locations and evaluated for processing quality. Market development activities in Mexico and Japan focused on white food type sorghums for milling into food ingredients. The sorghum meal had excellent extrusion properties. Extrudates were bland flavor, light color and produced excellent savory or sweet snacks.
IMPACT: 2000/01/01 TO 2000/12/31
New food sorghums are being processed into value added products for ethnic and dietary niche markets. This source of good quality sorghum is available for use in food and feed products. Applications in bakery products, snacks, ready to eat breakfast cereals are being evaluated domestically and internationally. Additional new earlier maturing food hybrids are in advanced stages of development. This information and grain samples were supplied to potential Japanese food processors by US Grains Council. L. Rooney provided technical assistance in Japan and Mexico. New markets for food sorghum are possible.
PROGRESS: 1999/01/01 TO 1999/12/31
The availability of identity preserved food sorghums in West Texas is a significant output from this project. Food sorghums produce grains with tan plant color and straw glumes that permit optimum decortication via abrasive milling. Some of these hybrids with outstanding grain yields are grown on significant but limited acreage for identity preserved marketing. High humidity during maturation causes stained kernels that yield off color flour and reduced milling yields. Mexican style cookies containing 50 percent sorghum and 50 percent wheat flours had excellent organoleptic properties. The texture of 100 percent sorghum flour cookies improved significantly by addition of 5 percent pregelatinized waxy corn starch. The starch apparently covers the sorghum particles reducing their sharp edges and binds them together. Brown, black and red sorghum bran fractions contained relatively high levels of phenols with the brown sorghum bran equivalent to blueberries in catechin equivalents, ORAC values and total phenol content. The brown bran produced bread with excellent brown color at the 10 percent level of substitution. Tortilla chips from sorghums high in phenols have significantly different colors; some produce very attractive red and blue chips. Thus, sorghum can be used in functional foods including those with high levels of anti-oxidants. Native soy flour retarded the staling of corn tortillas and may have a significant synergistic effect when combined with CMC. The structure of tortillas containing 5 percent soy was significantly different; starch changes during storage were reduced. Likewise addition of 1 percent vital wheat gluten reduced staling by improving rollability and flexibility of tortillas. Other additives including fibers from wheat bran are promising. Corn proteins may affect the structure and properties of masa and the staling of tortillas. Use of enzymes and grain with differing levels of protein are under evaluation. Our texture measurements are effective in measuring small differences in properties of tortillas. More than 1,800 preliminary wheat nursery samples were analyzed for hardness, milling and mixing properties. The single kernel hardness tester effectively eliminates a large proportion of experimental wheat lines in early stages of selection. The data presented prior to fall planting permits elimination of undesirable quality progeny. Presentations on maize and sorghum quality were made to numerous end users and overseas grain buyers.
IMPACT: 1999/01/01 TO 1999/12/31
New food type sorghums are being grown by some producers who have received from 10 to 25 cents per bushel more for the grain. Value added sorghum products for ethnic and dietary markets are being sold. Applications in bakery products, brewing, etc., are enhanced with the new grain types. Our techniques for evaluation of alkaline cooking properties of maize are used by the seed and food industry.
PROGRESS: 1998/01/01 TO 1998/12/31
Sorghum inbreds with improved dry milling quality were developed through collaboration with sorghum breeders. They produce white or red food grains with tan secondary plant color and straw glumes that permit optimum decortication via abrasive milling. They can be further milled into flour to produce excellent milled fractions for food products. Some of these hybrids have outstanding grain yields and are grown on limited acreage currently for value added foods. Certain inbreds like Tx635 produce grain with optimum grain quality and high yields in some locations. Several hundred sorghum lines were evaluated for dry milling, endosperm color and weathering to develop molecular markers. Waxy and heterowaxy sorghums substituted for 10% of maize produced tortillas with improved flexibility and rollability after storage. Tortilla chips from sorghums high in phenols have significantly different colors; some produce very attractive red and blue chips. The availability of identity-preserved food sorghums in West Texas is a major output of this project. Sorghum producers are utilizing these concepts in their marketing plans. In our pilot plant, waxy corn (10%) substituted for maize significantly improved the texture of staled tortillas. This concept was confirmed in a commercial tortilleria; the commercial tortillas were judged as too flexible and the masa had a slightly sticky consistency. However, we believe that waxy corn combined with normal corn improves tortilla texture significantly and modifies the structure of fried and baked chips. We published three objective methods for evaluation of tortilla texture which facilitates study of enzymes and other additives on tortilla staling. Corn samples from university and commercial companies were evaluated for alkaline cooking characteristics using our laboratory and pilot plant procedures. Laboratory trials to develop a nixtamalization method to produce masa without generating waste water and dry matter losses was successful in producing tortillas. The corn was decorticated to remove 5% of the initial weight followed by cooking in limited water and 0.7 % lime (based on corn). The cooked corn was held for a short time (1 hr), stone ground into masa and baked into tortillas. The alkaline flavor and texture were excellent. Tortillas were slightly darker. The potential to develop a more efficient way of manufacturing masa is promising. A new hard red wheat was released from the TAES wheat improvement program. We analyzed 1500 or more preliminary nursery samples for hardness, milling and mixing properties. The single kernel hardness tester eliminates a large proportion of experimental wheat lines in early stages of selection. The data are presented before planting to eliminate undesirable quality progeny. Standardization of whole kernel NIR for sorghum, maize and their products (masa, chips, flours, grits, etc.) was initiated. Presentations on maize and sorghum quality were made to numerous end-users and overseas grain buyers. Corn tortilla staling is a major problem affecting marketing. The combination of techniques and information can lead to improved quality products.
PROGRESS: 1997/01/01 TO 1997/12/31
Major factors affecting the dry milling properties of sorghum include kernel size, shape, pericarp color, plant color, weathering, molds, hardness, density, flotation and endosperm texture. White pericarp, tan plant sorghums had the highest yield of decorticated grain with the lightest color especially when sorghum matured under high humidity. The purple pigments permeate the endosperm and greatly darken the decorticated grain and flour produced therefrom. Sorghum from the food type hybrids produced light color, bland flavor tortilla chips, baked chips, noodles and other products including bread. Tortilla chips from a black sorghum had excellent flavor and a deep purple color. Red sorghums did not produce bright red tortillas as we hoped. The white food type sorghums are being grown in large quantities for identity preserved markets including ethnic and dietary groups. Methods to characterize dry masa flour were evaluated. The consistometer appears promising as a quick, simple, inexpensive technique for quality control. Bending and extensibility tests have been standardized to evaluate corn tortilla texture objectively. A blend of amylases and CMC improved the shelf life of corn tortillas significantly. The changes in starch during tortilla staling appear to be easily characterized by use of a rapid viscosity analyzer as well as HPSEC. Addition of alkali cooked corn bran to tortillas significantly improves the keeping properties but does darken the color significantly. Methods to cook corn more efficiently are being investigated. These experiments increase our understanding of critical factors affecting quality of corn and sorghum, and leads to better markets and more efficient processes for these grains.
PROGRESS: 1996/01 TO 1996/12
An air impingement oven was used to bake low-fat tortilla chips. The best baked chips were made when waxy rice, corn or sorghum flours were combined with dry masa. The texture and taste was significantly improved. A combination of ESEM, SEM and light microscopy effectively documented differences among processed products. ESEM provides a powerful tool for processed products containing water and oil. The dry milling properties of sorghum hybrids were evaluated at several locations in Texas. Some locations were badly weathered due to high moisture during maturation. Hybrids with tan plant color and straw colored glumes had significantly improved dry milling properties. The white purple or red plant color sorghums do not have acceptable milling quality when there is weathering or molds. We found that red sorghums with tan plant color had greatly improved dry milling properties and produced light-colored products. Five objective methods of evaluating tortilla texture were used to monitor the changes in staling during storage. A bending and a rolling test were very sensitive to changes in texture and could be used efficiently in a tortilleria. Hardness of corn masa was objectively evaluated efficiently by using a TPA procedure. Factors affecting masa adhesiveness were particle size distribution, water content and storage time.
PROGRESS: 1995/01 TO 1995/12
Three years of data on steam flaking of sorghum confirm that waxy sorghum flakeshad the largest diameter, greatest flake stability, best appearance, lowest bulk density, and the most tolerance to handling. Flakes of white, tan food type commercial hybrids had outstanding appearance. Commercial red, cream and yellow sorghum hybrids had similar steam flaking properties. There was no difference among sorghum hybrids in energy consumed although tempering the grain prior to flaking reduced energy consumption significantly and enhanced the appearance and durability of the flakes. Commercial conditioning agents did not enhance water uptake or break down the kernel structure. Flour and various mixes from food sorghums are commercially available for special markets. Identity preserved food sorghums have been shipped to Africa for use in foods. Sorghum hybrids with a white endosperm devoid of yellow pigments are preferred for food in South Africa. The Rapid Visco Analyzer provides useful information on the cooking characteristics of corn, but the floatation method was the best predictor of alkaline cooking quality and of dry milling performance. The TADD hardness index was highly correlated with the MEF values for corns grown in Texas and Indiana. Several hybrids with improved quality for dry milling and alkaline cooking looked promising.
PROGRESS: 1994/01 TO 1994/12
Dorado, a white tan food sorghum, has high levels of enzymes and significantly less dry-matter losses than other varieties. Sufficient variation exists among sorghum cultivars to enable selection for improved enzyme levels in malt. New food type sorghum grains produce light-color grits at higher recovery rates. Their superior performance has been confirmed in commercial brewing trials in Mexico. Significant differences were found in steam flaking characteristics among several sorghum hybrids. Waxy sorghum flakes had the largest diameter, greatest flake stability, best appearance, lowest bulk density, and the most tolerance to handling. Flakes of a white, tan food type commercial hybrid had outstanding appearance. It required significantly less time to process than other sorghums. If this observation can be repeated, it may be possible to produce sorghums with much greater efficiency for flaking. Quality data on samples from the Texas experimental food corn trials grown at 5 locations were used to produce the Texas Supreme list which is published by the Texas Corn Producers Association. The RVA predicts cooking characteristics of corn; the best single method was the floatation technique. The TADD hardness index was highly correlated with the MEF values for corns grown in Texas and Indiana. The RVA, mixograph and viscosity measuring devices have been used to evaluate variations in dry masa flour quality.
- Funding Source
- Nat'l. Inst. of Food and Agriculture
- Project source
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- Natural Toxins
- Viruses and Prions
- Bacterial Pathogens
- Chemical Contaminants
- Food Preparation and Handling
- Grains, Beans, Legumes