58 research outputs found
Overcoming constraints to utilization of sorghum and millet
Sorghum and pearl millet are used in a wide variety o f traditional foods in the
semi-arid tropics. However, their use as food is declining in urban areas as wheat, rice,
and maize products become more plentiful. Lack o f a reliable supply o f high quality
grain for processing severely limits the acceptance o f sorghum and pearl millet.
Shelf-stable products are in short supply because the grains available for processing
are o f inferior quality. Technology is availablefor processing sorghum andpearl millet;
however, major extension and improved cultivars are needed. Other constraints to the
use o f sorghum and pearl millet include their image as “second class ” crops, the tannins
in sorghum, low cost imported wheat, rice, and maize, and government policies.
Breeders must work diligently to develop new cultivars, targeting total units o f useful
food or feed per hectare. Improved end-use quality will allow value-added processing,
which could improve farm income from identity-preserved grain
Effects of growth conditions on grain molding and phenols in sorghum caryopsis
Received 9 March 1989; Available online 27 July 2009.
Phenolic compounds (PC) and phenolic acids (PA) were quantified in mature caryopses of sorghum grown in wet or dry environments. Seventeen cultivars varying in pericarp color and presence of a pigmented testa exhibited different levels of resistance to molding in the wet environment. Sorghum caryopses with a white pericarp contained lower levels of free PC (14ÎĽg/caryopsis) than those with a red pericarp (41 ÎĽg/caryopsis) when grown in the dry environment. This difference diminished under humid conditions. Cultivars with a pigmented testa were more resistant to grain molding, contained higher levels of free PC (151 ÎĽg/caryopsis), and had a softer endosperm texture than cultivars without a pigmented testa. In cultivars without a pigmented testa, higher levels of free PC and free PA, especially free p-coumaric, ferulic, and caffeic acids, were observed in mold-susceptible cultivars. A scatter plot of free PC vs. free p-coumaric acid indicated that mold-susceptibility was related to higher levels of p-coumaric acid, regardless of environment
Particle Size Effects on the Quality of Flour Tortillas Enriched with Whole Grain Waxy Barley
Wheat tortillas were enriched with whole barley flour (WBF) of different particle sizes including 237 µm (regular [RD. 131 µm (intermediate [IM]). and 68 µm (microground [MG], Topographical and fluorescent microstructure images of flours, doughs, and tortillas were examined, Flours and tortillas were analyzed for color, protein, ash, starch, moisture. and β-glucan content. Farinograph testing was conducted on the flour blends, Water activity and texture analyses of tortillas were conducted, A 9-point hedonic scale was used by 95 untrained panelists to evaluate tortilla appearance, color, flavor, texture, and overall acceptability, Two commercial products (CP) were included in some analyses, As WBF particle size decreased, color was lighter; protein, moisture content and mixing stability decreased; ash, starch content, water absorption and farinograph peak time increased: and β-glucan content was constant. WBF tortillas were darker than the control (C), while 1M and MG tortillas had lower peak forces than C, No flavor differences were reported among C, R, and MG tortillas but higher scores were given to both CP in all attributes tested, Tortillas made with the largest WBF particle size (R) were the most similar in protein content, texture and flavor when compared with C tortillas made with refined bread flour
Effects of Genotype and Growth Temperature on the Contents of Tannin, Phytate and in vitro Iron Availability of Sorghum Grains
Background: It has been predicted that the global temperature will rise in the future, which means crops including sorghum will likely be grown under higher temperatures, and consequently may affect the nutritional properties. Methods: The effects of two growth temperatures (OT, day/night 32/21°C; HT 38/21°C) on tannin, phytate, mineral, and in vitro iron availability of raw and cooked grains (as porridge) of six sorghum genotypes were investigated. Results: Tannin content significantly decreased across all sorghum genotypes under high growth temperature (P ≤0.05), while the phytate and mineral contents maintained the same level, increased or decreased significantly, depending on the genotype. The in vitro iron availability in most sorghum genotypes was also significantly reduced under high temperature, except for Ai4, which showed a pronounced increase (P ≤0.05). The cooking process significantly reduced tannin content in all sorghum genotypes (P ≤0.05), while the phytate content and in vitro iron availability were not significantly affected. Conclusions: This research provides some new information on sorghum grain nutritional properties when grown under predicted future higher temperatures, which could be important for humans where sorghum grains are consumed as staple food
Wheat Tortilla Quality: Impact of Amylose Content Adjustments Using Waxy Wheat Flour
Amylose content is closely related to wheat flour pasting or thermal properties, and thus affects final food qualities. Fourteen flour blends with amylose content ranges of \u3c 1 to 29% were used to study tortilla production and quality parameters. Reduced amylose contents decreased dough stickiness and pliability; low amylose doughs were also very smooth in appearance. Very low flour amylose content was associated with earlier tortilla puffing and poor machinability during baking, darker color, low opacity, larger diameters, and reduced flexibility after storage. Tortilla texture analysis indicated that lowering amylose content gave fresh tortillas higher extensibility; after three or more days storage, however, low amylose flours required more force to break the tortillas and the rupture distances became shorter. These results, as reflected in covariate analysis, were not significantly reflected by the flour blend\u27s protein content, swelling volume/power, SDS-sedimentation volume, mixograph dough development time, or mixograph tolerance score. Based on our observation of an initial increase in extensibility with reduced-amylose tortillas, adding 10-20% waxy flour into wild-type flours should be ideal for restaurant (on-site) tortilla production or circumstances where tortillas are consumed shortly (within a day) after production. The optimal flour amylose content for hot-press wheat tortilla products is 24-26%
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