Compositional,functional and storage properties of flours from raw and heat processed African breadfruit (Treculia africana Decne) seeds

African breadfruit (Treculia africana Decne) seeds were either boiled or roasted and then milled into flour. Chemical composition, functional properties and storage characteristics of raw and treated flours and the effect of partial proteolysis on selected functional properties of the raw flour were determined. Raw flour contained 20.1% crude protein, 2.5% total ash and 13.7% fat. Heat processing significantly (p<0.05) improved in vitro protein digestibility, and water and fat absorption capacities but decreased bulk density, nitrogen solubility, emulsion and foaming properties, trypsin inhibitor, and phytic acid and polyphenol contents of the samples. Boiling proved more effective than roasting for improving protein digestibility, emulsion capacity and foam stability and reducing antinutritional factor levels. Partial proteolysis increased nitrogen solubility, bulk density and water and fat absorption capacities but decreased foam capacity at hydrolysis levels greater than 35%. Fatty acid and peroxide values of the samples increased during storage. Compared to raw samples, heat processed samples had significantly (p<0.05) lower and more acceptable peroxide values and free fatty acid contents and higher and more stable water (3.0 g/g sample) and fat (2.4 g/g sample) absorption capacities.     

Physico-chemical properties and acceptability of yam flour substituted with soy flour

Yam flour was substituted 10, 20 and 40% with defatted and full fat soy flour. The effect of the substitution on the proximate composition, swelling power, solubility, water binding capacity and Brabender visco amylograph cooking properties of the yam flour and acceptability of the cooked paste (amala), were evaluated. Protein contents of the mixtures were 23.0 and 25.5% on substituting 40% full-and defated soy flours for yam flour; ash and crude fibre contents increased while carbohydrate content, swelling power, Brabender paste viscosities decreased with increase in soy flour substitution of yam flour. Colour, texture, taste and overall acceptability of pastes (amala) from the mixed flours were rated lower than that of yam flour. Up to 10% defated and 20% full fat soy flour substitution for yam flour was acceptable for amala.     

Proximate composition and selected functional properties of fermented and unfermented African oil bean (Pentaclethra macrophylla) seed flour

Flour samples were prepared from fermented and unfermentedAfrican oil bean (Pentaclethra macrophylla) seeds (AOBS). The flour samples were evaluated for proximate composition and certain functional properties. The influenceof defatting on these properties was also determined. Fermentation significantly increased (p<0.05) the proteinand decreased the crude fiber, ash, fat and carbohydrate contents of the AOBS flours. The nitrogen solubility of both fermented and unfermented flours was pH dependent withminimum and maximum solubility at pH 4.0 and pH 8.0, respectively, and with increased nitrogen solubility in the fermented sample. The fermented and unfermented flour sampleshad least gelation concentrations of 14 and 16% (w/v), respectively. The water absorption capacity and foam capacitiesof the fermented flour were 36 and 34%, respectively, over the unfermented seed flour. On the other hand, fermentation decreased the fat absorption capacity, emulsion activity and emulsion and foam stabilities. Fermentation decreased (p<0.05) the bulk density of AOBS flour by 15%. Defattingimproved all the functional properties evaluated except emulsion activity. These results indicate potential food usesof fermented and unfermented AOBS flour samples as protein supplements in diets and as functional ingredients in formulated foods.     

Chemical composition and selected functional properties of sweet orange (Citrus sinensis) seed flour

Flour samples were prepared from dehulled and undehulledsweet orange (Citrus sinensis) seeds. The flour samples were evaluated for proximate composition, mineralcontent and selected functional properties. Proximate analysis showed a composition of 54.2% fat, 28.5% carbohydrate, 5.5% crude fiber, 3.1% crude protein and 2.5% ash for the dehulled orange seed flour (dry weight).Mineral analyses showed high levels of calcium and potassium in flour samples. Partially defatted and undefatted flour samples prepared from dehulled orangeseeds had least gelation concentrations of 10 and 12%(w/v), respectively. Water absorption capacity for thedefatted and undefatted dehulled flour samples were 240and 220%, respectively. Defatting improved oil absorptioncapacity of the orange seed flour by 84%. Emulsion activity, emulsion stability and foaming capacity decreasedfollowing defatting of flour. Foam prepared from defattedflour was less stable than that from full-fat flour.Incorporation of NaCl up to 0.2 M improved the foamingcapacity of orange seed flour.     

Preparation and properties of flours and protein concentrates from raw, fermented and germinated fluted pumpkin (Telfairia occidentalis Hook) seeds

In vitro protein digestibility, chemical composition and selected functional properties of flours and protein concentrates prepared from raw, fermented and germinated fluted pumpkin (Telfairia occidentalis Hook) seeds were studied. Protein concentrates prepared by an alkaline extraction process had increased crude protein contents (61.5–70.8%) compared to flour samples (46.4–52.7%). The yields of protein concentrates ranged from 24.5% to 29.4% while values for protein recoveries varied between 64.8% and 65.2%. Protein concentrates also had increased foam volume and decreased foam stability (100% decrease over a 2 h period), compared to flour samples. Fermentation and germination were observed to significantly (p<0.05) lower polyphenol and phytic acid contents, but increased protein digestibility of fluted pumpkin seed flours and concentrates. Both raw flour and concentrate were significantly (p<0.05) higher in water absorption capacity than germinated or fermented flours and concentrates. Protein concentrates had comparatively better fat absorption properties than the flour samples. Hence protein concentrates may prove to have useful applications in ground meat formulations.     

Effects of debittering methods on the proximate composition,organoleptic and functional properties of sesame (Sesamum indicum L.) seed flour

Sesame seeds were boiled and allowed to sprout under ambient condition (30±2 °C) with an objective to reduce or eliminate the bitter taste associated with them. The untreated seeds were used as a control. The proximate composition, functional and organoleptic properties of defatted sesame flour were assessed at room temperature. There was a slight increase (about 10%) in protein content of sprouted seeds. The foaming capacity of flours from untreated, sprouted and boiled seeds were 34.6, 38.5 and 11.5%, respectively. The flour from the boiled seeds had the highest foam stability. Flours from untreated or sprouted seeds, gelation started at the least concentration of 6% whereas that from boiled seed was 11%. The emulsion capacity of flours from the untreated or sprouted seeds was the same (27.6 g oil/g sample) while that from boiled seeds was 12.9 g oil/g sample. Emulsion stability with prolonged storage appeared to be more with flours from the sprouted or boiled seeds than that from the untreated ones. The water absorption properties of flours from the untreated, sprouted and boiled seeds were 8.0, 5.9 and 6.5 g H₂O/g sample, respectively whereas the oil absorption capacity same (5.9 g oil/g sample). The bitter taste in flours from the untreated or sprouted was high. The bitter taste was not detected in flour from boiled seeds and the functional properties of the flour were not deleteriously affected except foaming and emulsion capacity. Therefore, this boiling method of debittering sesame seed could be practised. The quality of sesame flour obtained with this boiling method could still serve its role in traditional dishes and in the formulation of some other conventional food products.     

Physical properties of wheat flour composites dry-coated with microparticulated soybean hulls and rice flour and their use for low-fat doughnut preparation

Air-classified wheat flour was dry-coated with microparticulated rice flour (30%, db) and/or microparticulated soybean hulls (up to 10%, db) using a hybridization system, and the physical properties of the dry-coated wheat flour were examined. The composite wheat flours exhibited the higher water-holding capacity but lower swelling power and oil-holding capacity than their counterpart mixtures. In pasting viscosity, the composites of wheat and rice flours had substantially lower values for peak viscosity and breakdown than did pure wheat flour. The incorporation of soybean hulls to the composites of wheat and rice flours further reduced the peak viscosity. The composites with rice flour and soybean hulls showed slightly higher melting (gelatinization) temperatures but lower melting enthalpy compared to the counterpart mixtures. By using the composite flours for the deep-fat fried doughnut preparation, the oil uptake could be substantially reduced by approximately 30%, in comparison to pure wheat flour or the mixture samples. The composite wheat flours with microparticulated rice flour and soybean hulls produced dough matrices with improved compactness and cell structure, which were attributed to the reduced fat uptake during frying.     

Physical properties of wheat flour composites dry-coated with microparticulated soybean hulls and rice flour and their use for low-fat doughnut preparation

Air-classified wheat flour was dry-coated with microparticulated rice flour (30%, db) and/or microparticulated soybean hulls (up to 10%, db) using a hybridization system, and the physical properties of the dry-coated wheat flour were examined. The composite wheat flours exhibited the higher water-holding capacity but lower swelling power and oil-holding capacity than their counterpart mixtures. In pasting viscosity, the composites of wheat and rice flours had substantially lower values for peak viscosity and breakdown than did pure wheat flour. The incorporation of soybean hulls to the composites of wheat and rice flours further reduced the peak viscosity. The composites with rice flour and soybean hulls showed slightly higher melting (gelatinization) temperatures but lower melting enthalpy compared to the counterpart mixtures. By using the composite flours for the deep-fat fried doughnut preparation, the oil uptake could be substantially reduced by approximately 30%, in comparison to pure wheat flour or the mixture samples. The composite wheat flours with microparticulated rice flour and soybean hulls produced dough matrices with improved compactness and cell structure, which were attributed to the reduced fat uptake during frying.     

Effect of blanching and ripening on functional properties of plantain (Musa aab) flour

Flours were prepared from raw and blanched samples of and ripe mature plantain Musa aab and examined for theirproximate composition, physical characteristics and functionalproperties. The plantain flours contained 3.5 g crude protein,2.5–3.5 g crude fat, 5.7–7.1 g moisture, 1.33–2.0 g crudefiber, 1.66–2.0 g ash, and 82.25–86.07 g carbohydrate per 100 gsample. The flours had bulk densities between 0.42–0.72 g/ml,emulsion capacities of 4.7–14.7%, water absorption capacitiesof 250–338%, oil absorption capacities of 214–371%,foaming capacities of 1.90–5.79%, least gelation concentrationsof 6–8%, and viscosities of 23.7–46.7 CP at 2% slurry concentration. Foaming capacity increased with increasing flourconcentration. Blanching considerably reduced the emulsion capacity and viscosity, while bulk density, water and oilabsorption capacities were increased by blanching. Ripening wasfound to have a negative effect on all the functional propertiesexamined except the bulk density, and gelation property. Unripe plantain could be used as an emulsifier and thickener in a foodsystem.     

Proximate composition and some functional properties of extrusion cooked soybean and sweet potato blends.

Mixtures of sweet potato flour and soy flour were made in a pilot mixer. They were moisturized with 18, 25, and 30% water and extruded in a single screw extruder at 80 rpm, using a die of 6mm. Extrusion temperature was maintained at 100 +/- 3 degrees C. Effects of adding soy flour into sweet potato flour, as well as variation in feed moisture on the composition and some functional properties of the extrudates were investigated. Increase in sweet potato content increased carbohydrate values. Protein increased with increase in soy flour. Feed moisture did not significantly (p < or = 0.05) affect extrudate composition. Increase in sweet potato content and feed moisture increased expansion ratio. Bulk density decreased with decrease in feed moisture, but increased with increase in soy flour. Starch content increased as sweet potato content increased. Degree of gelatinization increased with sweet potato content. Lower feed moisture enhanced gelatinization. Water absorption index (WAI) increased as sweet potato content increased. Feed moisture had a slight effect on WAI and water solubility index (WSI). Amylose increased with increase in sweet potato content. Increase in soy flour led to an increase in yellowness (b*) of extrudates.     

Proximate composition and selected functional properties of Detarium microcarpum

The proximate composition and functional properties of Detariummicrocarpum seed flour were evaluated. The dehulled seed flour contained3.5% moisture, 3.5% ash, 2.9% crude fiber, 15% crude fat, 37.1% crude protein and 39%carbohydrate. Functional properties showed bulk densityof 0.86 g/cm³ for dehulled and 0.92 g/cm³ for undehulled flour.Water absorption capacity was 4.9 g/g for dehulled and 5.1 g/g forundehulled seed flour; oil absorption capacity was 0.75 g/g for dehulled.The emulsion activity was 4.4% and 4.3% for dehulled and undehulled,respectively. The results obtained above showed that the Detariummicrocarpum seed flours have good nutritional quality and the functionalproperties confirmed their suitability for use in various food preparations.As a result, its present limited use should be expanded into additionalopportunities.     

Proximate Composition and Functional Properties of Fullfat and Defatted Beniseed (Sesamum Indicum L.) Flour

The proximate composition and functional properties of fullfat and defatted beniseed (Sesamum indicum L.) flour were evaluated. Functional properties studied were foam capacity and stability, water and oil absorption, bulk density, emulsion capacity and nitrogen solubility. Defatting increased the crude protein, ash, crude fiber, carbohydrate and mineral contents. Defatted flour showed comparatively better foam capacity and stability, water absorption and emulsion capacities but diminished bulk density and oil absorption capacity. Nitrogen solubility was pH dependent with a minimum at pH 4 and maximum at pH 8. Maximum nitrogen solubility (95%) was recorded for defatted flour while that for the fullfat flour was 60%. The proximate composition and functional properties of the samples suggest that beniseed flour would have useful application in fabricated foods.     

Protein and starch digestibilities and mineral availability of products developed from potato,soy and corn flour

A technique for development of potato flour was standardized. Five products viz. cake, biscuit, weaning food, panjiri and ladoo were prepared incorporating potato flour, defatted soy flour and corn flour. Baking and roasting were the major processing techniques employed for the development of these products. Protein, ash and fat contents of potato flour were almost similar to those of raw potatoes. Significant differences in protein, ash and fat contents of all the products were observed. Protein and starch digestibility of potato flour was significantly higher than that of raw potatoes. Protein digestibility increased by 12 to 17 percent on baking or roasting of products. Processed products had significantly higher starch digestibility and mineral availability compared to raw products. Thus, it can be concluded that roasting and baking are effective means of improving starch and protein digestibility and mineral availability of products.     

Proximate composition and some functional properties of extrusion cooked soybean and sweet potato blends

Mixtures of sweet potato flour and soy flour were made in a pilot mixer. They were moisturized with 18, 25, and 30% water and extruded in a single screw extruder at 80 rpm, using a die of 6mm. Extrusion temperature was maintained at 100 ± 3^°C. Effects of adding soy flour into sweet potato flour, as well as variation in feed moisture on the composition and some functional properties of the extrudates were investigated. Increase in sweet potato content increased carbohydrate values. Protein increased with increase in soy flour. Feed moisture did not significantly ( p 0.05) affect extrudate composition. Increase in sweet potato content and feed moisture increased expansion ratio. Bulk density decreased with decrease in feed moisture, but increased with increase in soy flour. Starch content increased as sweet potato content increased. Degree of gelatinization increased with sweet potato content. Lower feed moisture enhanced gelatinization. Water absorption index (WAI) increased as sweet potato content increased. Feed moisture had a slight effect on WAI and water solubility index (WSI). Amylose increased with increase in sweet potato content. Increase in soy flour led to an increase in yellowness (b^*) of extrudates.     

Effect of germination time and temperature on the functionality and protein solubility of sorghum flour

Sorghum was germinated for different time (12, 24, 36 and 48 h) at different temperatures (25, 30 and 35 °C) and the changes in their nutritional and functional properties of germinated sorghum flour were assessed and compared with native sorghum flour. Germination inversely affects the crude protein, fat, fibre and ash content. A decrease in water absorption and swelling power and increase in oil absorption capacity was observed due to enzymatic starch modification as the germination duration progressed. Germination of sorghum increased the gel consistency while paste clarity was decreased as compared to native flour. Proteins were modified by action of enzymes during higher germination time and temperature conditions, which results in significantly higher protein solubility of germinated sorghum flour, which also result in enhancing the foaming and emulsifying properties of the flour. Lowest % synersis value and least gelation concentrations were observed in native sorghum has, which increased during germination and were highest in sorghum germinated for 48 h at 35 °C. Germination in overall can be used as low cost natural bio-processing technique for the preparation of modified flour with enhanced function properties without chemical modification or genetic engineering.     

Effects of extrusion cooking on functional properties of mixtures of full-fat soy and sweet potato

Full-fat soy and sweet potato were extruded at 0:100, 25:75, 50:50, 75:25 and 100:0 ratios in an Insta-Pro 600 single screw extruder operated at 180, 200, 220 rpm respectively. Functional properties: bulk density, expansion ratio, water absorption and solubility indices and trypsin inhibitor were assayed. Results showed that addition of soybeans to sweet potatoes considerably increased the protein, fat, ash and trypsin inhibitor levels of the raw material mixtures. It also led to decreases in viscosities of raw mixtures, with corresponding increases in pasting temperatures. Addition of soybean significantly (p<0.05) affected expansion ratio, water absorption and solubility indices and trypsin inhibitor but not bulk density. Variation in screw rotation speed (rpm) significantly (p<0.05) affected only water solubility index at increasing speed. Extrudates generally received severe heat treatment, rendering them applicable only in soup bases, flour mixes and breakfast foods.     

Selected nutritional,physical and sensory characteristics of pan and flat breads prepared from composite flours containing fababean

Composite flour blends containing wheat (W), fababean (F), cottonseed and sesame flours were formulated to provide the FAO/WHO/UNU protein requirements for the 2–5 year old child, and evaluated in pan and flat bread applications. Water absorption of composite flour doughs was up to 35% greater than the control but gluten strength and slurry viscosities were markedly reduced. Loaf volume and specific volume of pan breads prepared from composite flours were 25–60% less than that of the control bread but flat breads tolerated the protein supplements extremely well. The W/F flat bread, containing 27% of fababean flour, received acceptable taste, texture and colour scores and was only slightly inferior to the control in puffing and layer separation. Additions of cottonseed or sesame flours to the W/F blend failed to improve sensory properties of the flat breads.     

Chemical,sensory and rheological properties of porridges from processed sorghum (Sorghum bicolor,bambara groundnut (Vigna subterranea L. Verdc) and sweet potato (Ipomoea batatas) flours

The chemical, sensory and rheological properties of porridges made from blends of sprouted sorghum, bambara groundnuts and fermented sweet potatoes were examined. Sorghum and bambara groundnuts were sprouted for 48 h while sweet potatoes were fermented for the same period. Blends were formulated from the processed ingredients in the ratio of 60:40:0, 57:42:1, 55:44:1 and 52:46:2 (protein basis) of sorghum, bambara groundnuts and sweet potatoes. Porridges were prepared from the composite flours and the traditional sorghum complementary food. Standard assay methods were used to evaluate the flours for nutrient composition. The porridges were also tested for sensory properties and viscosity. Processing increased the levels of most of the nutrients evaluated. Relative to the sorghum traditional complementary food, thecomposite flours had higher levels of lipids, protein, ash, crude fiber and minerals (p<0.05). The porridges from the composite flours were generally liked slightly by the panelists and were about seven times less viscous than the porridge from the traditional sorghum complementary food. Use of the composite flours, particularly the 52:46:2 blend, as a traditional complementary food should be encouraged in Nigeria especially with the increasing cost of commercial complementary foods.     

Sensory evaluation and nutrient composition of weaning food from pregelatinized maize-sweet potato mixtures

Pregelatinized maize-sweet potato mix, fortified with soybeans and groundnut flours, was evaluated for its acceptability as a weaning food and for nutrient composition. An acceptable product had 14.3, 6.4, 2.4 and 67.4%, respectively, for its protein, fat, ash and carbohydrate contents. Values for calcium, phosphorus and and iron contents were 59.6, 187.5 and 2.4 mg/100 g, respectively, while the most predominant fatty acids were linoleic, oleic and palmitic acids. The product, which had a chemical score of 85.34 for its protein value, was limiting in threonine.     

Effect of pre-dehulling treatments on the composition of seeds of the legumeAfzelia africana and its potential use in pastries

Flour was prepared from seeds ofAfzelia africana dehulled by different treatments and used to replace 10, 20, 30, 40 and 50% wheat flour in biscuits and doughnuts. The composition and water and oil absorption properties of the flour blends were evaluated. The biscuits and doughnuts made from each flour blend were evaluated organoleptically. The composite flour containing the highest proportion (50%) ofA. africana seed flour contained the highest levels of protein and fat, exhibited the highest water absorption property but the lowest oil absorption capacity. Sensory scores showed high overall acceptability for products with a 10–30% level of substitution.