Growth and apparent absorption of minerals in broiler chicks fed diets with low or high tannin contents.

Sorghum grains with low (0.28 per cent catechin equivalent (%CE) or high (1.36%/DCE)) tannin contents were used to study the effect of tannin on growth and on the apparent absorption of Ca, P, Mg, Na, K, Fe and Co by chickens. High-tannin sorghum caused a highly significant (p < or = 0.01) reduction in the weight gain and feed intake of broiler chicks compared to low-tannin sorghum and increased the feed conversion ratio (p < or = 0.01). The amount of tannin did not affect mortality. The apparent absorption of Ca, P, Mg, Na, K, Fe and Co was reduced (p < or = 0.01) by feeding sorghum grains with a high tannin content.

Biochemical and sensory evaluation of wheat bran supplemented sorghum bread.

Addition of wheat bran to sorghum flour (Dabar cultivar) at two extraction rates 72% and 80% resulted in lowering reducing sugars. The percent decrease was 75.6% compared with the control at the end of fermentation period. There was a highly significant (p < or = 0.05) increase in crude fiber content as a result of addition of wheat bran. The increase was from 0.8 to 5.2 and from 0.5 to 5.3% for the 80% S/WB and 72% S/WB blends, respectively. Sorghum bread containing wheat bran was lower in reducing sugars and showed a significant increase (p < 0.05) in starch content. Sorghum bread containing wheat bran resulted in a lower in vitro protein and starch digestibilities.

Changes in fatty acids composition during seed growth and physicochemical characteristics of oil extracted from four safflower cultivars.

Fatty acid contents at different stages of maturity and physicochemical characteristics of oil extracted from mature seeds of four safflower cultivars (S208, S400, S541, and S303) were studied. Results indicated that for all cultivars both saturated and unsaturated fatty acid contents fluctuated with seed growth and development. Palmitic acid content decreased up to day 20 after which it started to increase for the S400, S541, and S303 cultivars, while for S208 it progressively decreased. Stearic acid fluctuated with seed growth and development. Oleic acid showed slight changes with seed growth and development, while linoleic acid decreased with seed growth and development for the S400, S541, and S303 cultivars while for S208 after day 30, it started to increase significantly. For all cultivars, glyceride contents varied among the cultivars with maximum values of 97.70, 2.80 and 0.20 for tri-, di- and monoglycerides, respectively. Physicochemical investigation of mature seed oils showed that the color, density, refractive index, free fatty acids, peroxide value, saponification value and unsaponifiable matter were similar for all cultivars while viscosity, iodine value, and acetone insoluble matter varied among the cultivars.

Effect of fermentation on sorghum protein fractions and in vitro protein digestibility.

Changes in pH, titratable acidity, total soluble solids and proteins of Dabar sorghum (Sorghum bicolor (Linn) Moench.) during natural fermentation at 37 degreesC for up to 36 h were monitored. The pH of the fermenting material decreased sharply with a concomitant increase in the titratable acidity. Total soluble solids increased with progressive fermentation time. The crude protein and non-protein nitrogen slightly increased during the last stages of fermentation. The in vitro protein digestibility markedly increased as a result of fermentation. The globulin plus albumin fractions increased significantly (p < or = 0.05) during the first 8 h of fermentation. Kaffirin fraction decreased during the first 8 h of fermentation but increased sharply as fermentation progressed. Cross-linked kaffirins fluctuated during the fermentation process. Glutelin like protein, which was the minor fraction, true glutelins, the second most abundant fraction, together with non-extractable proteins fluctuated during the fermentation process.

Changes in chemical composition, minerals and amino acids during seed growth and development of four safflower cultivars.

Investigation of four safflower (Carthamus tinctorius L.) cultivars (S208, S400, S541 and S303) showed that when the seeds were harvested at different stages of growth and development (10, 20, 30, and 40 days) after flowering, moisture content significantly decreased with time. Oil, protein, ash and crude fiber were increased up to day 30. Thereafter, these parameters started to decline gradually with time. The cultivars differed in their final values; oil content of the seeds varied from 10.90 to 45.40%, moisture varied from 4.20 to 8.10% and from 8.50 to 11.10%, protein from 12.10 to 20.30% and from 13.40 to 29.60%, ash from 2.30 to 5.40% and from 2.80 to 6.50%, for the seeds and defatted meal, respectively. Crude fiber for the defatted meal was found to vary from 29.50 to 38.60%. Carbohydrate for all cultivars decreased rapidly up to day 40 with final values varying from 28.10 to 63.30% and from 56.70 to 70.30% for the seeds and defatted meal, respectively. Mineral content (Cu, Zn, Fe, Mg, Mn) fluctuated while phosphorus content significantly increased with time for all cultivars. Amino acid content of the defatted meal increased with time up to day 30 after which it started to decline gradually for all cultivars.

Effect of cooking on cowpea protein fractions.

Nine cowpea cultivars obtained from Wad Medani Research Station were used in this study. The variation in protein fraction was: albumins 4.0-12.0, globulins 65.6-79.7, prolamins 1.4-2.2, G1-glutelins 0.9-3.0, G2-glutelins 1.4-2.9, G3-glutenins 9.1-14.0 and insoluble protein 0.5-3.0%. Two cowpea cultivars, H8-14 and CB-46, selected for their high albumin content, were cooked in 150 ml of boiling distilled water under reflux for 45 minutes. The protein fractions in the cooked seeds were determined. Results indicated that albumin and globulin fractions decreased significantly (p < or = 0.05) for both cultivars after cooking. This decrease was accompanied by a significant increase in G3-glutelin fractions.

Changes in sugar, ash and minerals in four guava cultivars during ripening.

Investigation of four guava cultivars showed that when the fruits were harvested at different stages of growth and development, total sugars increased slowly during the initial growing period followed by rapid increase during maturation and ripening for all cultivars. The maximum level varied from 7.5 to 26.9%. Individual sugars: (fructose, glucose and sucrose) increased slowly during the initial growing period followed by rapid increase during maturation and ripening for all cultivars. The cultivars differed in their final sugar content; fructose varied from 5.6 to 7.7%, glucose from 1.9 to 18.1%, and sucrose from 6.2 to 7.8%. Total ash for all cultivars decreased slowly during the initial growing period followed by a sudden increase in the latter stage of maturation and ripening, with maximum level varying from 5.2 to 7.9%. Minerals: Ca, Mg, Na, K and P, for all cultivars decreased slowly during all stages of development. These results suggest that when guava fruits were picked 106-126 days after fruit set it ensures sufficient amount of total sugars and appreciable amount of minerals.

Effect of nitrogen fixation, nitrogen fertilization and viral infection on yield, tannin and protein contents and in vitro protein digestibility of faba bean.

A field investigation of two faba bean cultivars (cv.), Agabat and Silaim, showed that bean yellow mosaic virus (BYMV) infection reduced (p < or = 0.001) yield (Kg/ha), protein content and in vitro protein digestibility (IVPD) but increased (p < or = 0.05) tannin content (mg/100 ml). Nitrogen fertilization with viral infection significantly reduced yield and IVPD for cv. Silaim and increased (p < or = 0.05) protein and tannin contents. Nitrogen fertilization alone was found to increase (p < or = 0.05) yield, protein and tannin contents but slightly reduced IVPD. Rhizobium inoculation with viral infection significantly decreased yield per unit area, protein content and IVPD, but increased (p < or = 0.05) tannin content. Rhizobium inoculation alone significantly increased (p < or = 0.001) yield and tannin content and slightly increased protein content but decreased IVPD. The results indicated that nitrogen fertilization or nitrogen fixation increased yield, protein and tannin contents and decreased IVPD. Viral infection had an adverse effect on yield, protein content and IVPD but had no effect on tannin content.

Effect of reconstitution and Na2Co3 on tannin content and in vitro protein digestibility of faba bean cultivars.

Two faba bean cultivars (317/99/81 and Giza/402) obtained from Shambat Research Station in Northern Sudan, were used for this study. Investigation showed that the tannin contents of untreated seeds were 0.077% and 0.067% for cultivars 317/99/81 and Giza/402. In vitro protein digestibility values were 80.68% and 81.48% for the two cultivars, respectively. The extractable tannin content of the faba bean cultivars was markedly reduced by imbibing water or Na2CO3 solution into whole seeds and incubating them at 30 degrees C for 1, 3, 6, 12 or 24 hours, or at 100 degrees C for 5, 10 or 20 minutes. The extent of reduction depended on time, temperature, and Na2CO3 concentration; the percent tannin extracted and percent in vitro protein digestibility increased with time or Na2CO3 concentration, while application of high temperature reduced the time.