Effect of flour blending on functional, baking and organoleptic characteristics of bread

Soybean (full‐fat and defatted) and barley flours were incorporated into wheat flour at 5, 10, 15 and 20% substitution levels. The gluten content, sedimentation value and water absorption capacity of the flour blends and the mixing time of the dough decreased with increase in the level of soybean and barley flour separately and in combinations. Protein and glutelin contents increased significantly on blending of soyflour (full‐fat and defatted) to bread wheat flour. The breads prepared from the blends also varied in their loaf weight, loaf volume and sensory characteristics. The bread volume decreased with increasing amount of non‐wheat flour substitution. The crumb colour changed from creamish white to dull brown and a gradual hardening of crumb texture was observed as the addition of soybean (full‐fat and defatted) and barley flours increased. At the higher levels, the acceptability declined because of the compact texture of the crumb and the strong flavour of the product. The addition of 10% of soyflour (full‐fat and defatted) or 15% of barley flour, full‐fat soy + barley or defatted soy + barley flour to bread flour produced acceptable bread.     

Physicochemical and functional properties of full‐fat and defatted Moringa oleifera kernel flour

Full‐fat and defatted Moringa oleifera kernel flours were analysed for their functional properties. The effect of pH and NaCl concentrations on the functional properties of the flours was investigated following standard procedures. The protein content of full‐fat and defatted flour was 36.18 and 62.76 g/100 g, respectively. The concentrations of other proximate constituents of the defatted flour were higher than those of the full‐fat flour. Nitrogen solubility was lowest at pH of 4.0 and 9.0, respectively, with maximum solubility occurring at pH of 6.0. Defatting increased the water absorption and fat absorption capacities of Moringa oleifera kernel flour. The foaming capacity and foam stability of the defatted flour were 86.0% and 82.0 mL, whereas that of full‐fat flour were 20.6% and 18.5 mL respectively. The defatted flour showed better emulsification (97.2 mL g^?1) than full‐fat flour (66.0 mL g^?1). The least gelation concentration of the defatted and full‐fat flours was 14% and 16% (w/v) respectively. Moringa oleifera kernel flour can be a valuable source of vegetable protein in fortified food products formulation.     

Functional Properties of Defatted and Detoxified Madhuca (Madhuca butyraceae) Seed Flour

Functional properties of defatted and detoxified Madhuca (Madhuca butyraceae) seed flours were determined and compared with those of soybean flour. Soybean and detoxified Madhuca flours had higher water absorption capacities than defatted Madhuca flour. Due to the presence of saponins, the defatted Madhuca flour showed higher foaming capacity than the soybean and detoxified Madhuca flours.     

Formulation,Evaluation and Optimization of Tortillas Containing Wheat,Cowpea and Peanut Flours Using Mixture Response Surface Methodology1

The performance characteristics of tortillas, prepared with different composite blends of wheat, cowpea and peanut flours, were evaluated by mixture response surface methodology. Optimum wheat flour substitution levels were determined. Results indicated that wheat flour could be successfully replaced with up to 24% cowpea and 46% defatted peanut flours and result in tortillas with quality characteristics comparable to those from 100% wheat. Sensory evaluation indicated that beany flavor was the most limiting attribute. Sensory attributes correlated significantly with physical and compositional measures of tortillas and physical measures of tortilla dough.     

EXTRUSION OF MINCED CATFISH WITH CORN AND DEFATTED SOY FLOURS FOR SNACK FOODS

Response surface methodology (RSM) with a rotatable central composite design was used to determine an extrusion condition that would produce extrudates of a maximal expansion ratio from blends of catfish flesh (20%), corn flour and defatted soy flour (DSF) using a single‐screw laboratory extruder. Feed moisture, process temperature and DSF level were selected as independent variables. Analyses of the response indicated that the combination of 26.9% moisture, 160.1C and 4.95% DSF would result in extrudates with maximal expansion. The snack food made with the aforementioned combination and 74.74% corn flour in feed was slightly less dense than malted milk balls and much less hard than cocktail peanuts, according to a trained sensory panel. “Grain complex” was the most intense flavor note. When 1% garlic or onion powder was added to the feed formulation, the spice flavor notes were detected in extrudates. No fish flavor note was perceived in any of the extrudates.     

CORN MEAL/SOY FLOUR BLENDS: CHARACTERISTICS AND FOOD APPLICATIONS

SUMMARY –Protein quantity and quality of degermed corn meal were improved by supplementation with toasted defatted soy flour. Taste panel results indicated no significant change in preference, acceptability and similarity to corn meal when as much as 20% toasted defatted soy flour was contained in the blend. Flavor stability was adequate in blends containing toasted defatted, commercial processed full-fat or extrusion-cooked full-fat soy flours at the 15% level. Product color was changed more by the inclusion of toasted defatted than of full-fat soy flour in the blends. Satisfactory performance was found in chapatti and northern corn bread containing degermed corn meal with and without 15% toasted defatted, 20% commercial processed full-fat or 35% extrusion-cooked full-fat soy flours.     

Effect of lipoxygenase activity in defatted soybean flour on the gelling properties of soybean protein isolate

Soybean lipoxygenase was inactivated to different degrees by dry heating of defatted soybean flour for 0, 5, 10, 15, 20 and 25 min and soy protein isolates were prepared thereof by isoelectric precipitation of the water extract of the defatted soybean flour. The fluorescence emission intensity at 420 nm of the chloroform–methanol extract of soy protein isolates, which was indicator of the existence of peroxidized lipid, varied in parallel with the lipoxygenase residual activity in defatted soybean flours. The dispersion of soy protein isolate showed an increasing turbidity with the increase of lipoxygenase residual activity in the starting defatted soybean flour, suggesting an elevated tendency to form insoluble aggregates during the preparation of soy protein isolate. Small deformation rheological test revealed that the gelling times were shorter for those soy protein isolates derived from low lipoxygenase activity defatted soybean flours than that of high lipoxygenase activity. Frequency sweep showed that G′ of soy protein isolate derived from low lipoxygenase defatted soybean flour was independent of oscillation frequency in contrast to that of derived from non dry-heated defatted soybean flour, the latter showed a marked frequency dependence. Large deformation test revealed that the gel hardness increased about 10 times after dry heating of defatted soybean flour for 20 min. As the increase of the lipoxygenase residual activity, the gel permeability increased markedly, suggesting that soy protein isolate from high lipoxygenase defatted soybean flour produced coarser textured gel, which corresponded well with the results of scanning electron microscopy.     

The pasting behaviour of lactic‐fermented and dried uji (an East African sour porridge)

The effects of sun‐, cabinet‐, and drum‐drying on the behaviour of submerged culture lactic‐fermented pure cassava, maize and finger millet and composites of maize–finger millet and cassava–finger millet were investigated in a Brabender amylograph. The cereal flours and maize–finger millet composite had higher onset and peak gelatinization temperatures but lower peak viscosities than cassava or cassava–finger millet composites. Fermentation alone or in combination with drying increased the viscosity of the flours, except for the fermented and drum‐dried cassava–finger millet composite flour. This increased viscosity of uji on fermentation and drying makes it more difficult to cook. Fermented and drum‐dried flours recorded high initial viscosities, at 30 °C, when the amylograph was switched on. Copyright © 2003 Society of Chemical Industry     

THE EFFECTS OF FLAXSEED, SOY AND CORN FLOURS ON THE TEXTURAL AND SENSORY PROPERTIES OF A BAKERY PRODUCT

The objective of this study was to assess the effects of some healthy ingredients on the properties of a ring‐shaped bagel/pretzel‐type bakery product to offer an alternative product satisfying consumer demand. For this purpose, ground flaxseed, defatted soy flour and corn flour were blended at a weight basis with wheat flour at 5, 10 and 15%. The taste score decreased upon increasing the level of substitution of flaxseed, soy and corn flours. Samples containing 15% of flaxseed were rated poorest in taste. No significant difference was observed in crust color except 15% level of flaxseed. The control sample had highest crust color value. The crispness scores of control and other samples containing 5% corn flour were higher than that of other samples. The samples with 5% flaxseed flour had lower crust L values. Flaxseed, soy and corn flour showed significant effects on the hardness, cohesiveness, springiness, gumminess, fracture force and stiffness values (P < 0.05). Samples with 15% corn flour had the highest hardness value. The results of the present study suggest that flaxseed, soy and corn flours could be added to a typical snack formulation up to levels of 10% with a reasonable acceptance offering promising nutritious and healthy alternative to consumers.     

Organoleptic and nutritional evaluation of wheat breads supplemented with soybean and barley flour

Supplementations of soy (full fat and defatted) and barley flours to wheat flours at 5, 10, 15 and 20% levels were carried out to test the effects on organoleptic and nutritional evaluation of the supplemented bread. Additions of 15% barley flour, 10% soy flour (full fat and defatted), 15% barley plus full fat soy flour and 15% barley plus defatted soy flour to wheat flour produced acceptable breads. However, substitution of soy (full fat and defatted) and barley flours to wheat flour separately and in combinations at 20% levels did not produce organoleptically acceptable bread. Various nutritional parameters, such as protein, fat, total lysine, protein digestibility (in vitro), sugars, starch digestibility (in vitro), total and available minerals, antinutrients, dietary fibre and β-glucan were determined in supplemented and control bread. Increasing the level of substitution from 5 to 10% of full fat and defatted soy flour to wheat flour significantly (P<0.05) increased protein (from 12.1 to 13.7 and 12.4 to 13.8%), lysine (from 2.74 to 3.02 and 2.76–3.05 mg/100 g protein) and total calcium (from 70.2 to 81.4 and 71.9–81.8 mg/100 g) contents. However, there was also an increase in phytic acid (238–260 and 233–253 mg/100 g), polyphenol (324–331 and 321–329 mg/100 g) and trypsin inhibitor activity (193–204 and 193–198 TIU/g). When barley flour was substituted separately, and in combinations, with full fat and defatted soy flour up to 15%, this significantly increased the contents of protein, total lysine, dietary fibre and β-glucan. It may be concluded that breads supplemented with barley and defatted soy flour, up to a 15% level, are organoleptically and nutritionally acceptable.     

Nutritional,Functional and Physical Properties of Extrudates from Blends of Cassava Flour with Cereal and Legume Flours

Low protein and poor functionality limit the use of cassava flour in snack foods, which were modified using blends with cereal and/or legume flours. Native, malted (using alpha-amylase) as well as malted and pre-gelatinized was blended with cereal (finger millet and whole wheat flours) and/or legume (chick pea flour). Extrudates were prepared at a screw speed of 100 rpm and die temperature of 180 °C. Malted flour based extrudates had lower starch content than native flour. Gram malted cassava based blends gave products with the highest protein. In vitro starch digestibility was the highest for pre-gelatinized flour based mixes. Extrudates with low fat and energy have scope as low calorie snacks for obese and diabetic people.     

EFFECT OF PENTOSANASE ON DOUGH AND BREAD PROPERTIES PRODUCED BY DIFFERENT TYPES OF FLOURS

ABSTRACT

The effects of pentosanase at different doses (20, 60 and 100 ppm) on physical dough properties and bread quality were studied using three types of wheat flours. Flour A was a regular bread flour, flour B had a high hardness ratio and protein content, and flour C was prepared from the same blend of flour A but had a high extraction ratio. Regarding farinograph data, water absorption values of the high extraction (86%) flour C and high hardness (65%) blend flour B increased with introduction of pentosanase. Extensibility values of the flours increased moderately with pentosanase addition, while resistance and energy values decreased. The volume of breads made with flours C and B decreased upon addition of pentosanase. But loaf volume of breads prepared with regular bread flour A with 50% hardness and 76% extraction rate increased with high levels of pentosanase addition. In conclusion, flour A as a regular bread flour gave satisfactory results with pentosanase supplementations, whereas the harder‐blend (65%) and higher‐extraction‐rate (85%) flours from the same cultivars did not.

PRACTICAL APPLICATIONS

Pentosanase addition was more effective on soluble pentosans than on insoluble ones. Because of these effects, it enhanced the bread‐making properties of regular flour more effectively than those of the high‐extraction and harder‐blend flours of the same cultivars.

     

In-vitro multienzyme digestibility of protein of some plant source flours blended with bovine plasma protein concentrate

The in-vitro multienzyme protein digestibilities of the flours of maize, cassava, pigeon pea (Cajanus cajan), African yambean (Sphenostylis stenocarpa) and bambara groundnut (Vigna subterranea), blended with bovine plasma protein concentrate were investigated. The multienzyme system consists of trypsin, chymotrypsin and peptidase. It was found that the addition of bovine plasma protein concentrate improved the protein digestibility of the flours compared with flours without the additive. The digestibilities were increased by between 3% in bambara groundnut blended flour to about 10% in cassava blended flour. When the flours were wet-heat treated, the digestibilities further increased in all samples with increments between 7·5 % in bambara groundnut and 16·6% in cassava flour. Bovine plasma protein concentrate may be a good source of protein for the fortification of protein-deficient foods, particularly maize and cassava flours.     

PHYSICAL AND SENSORY CHARACTERISTICS OF FRIED COWPEA (VIGNA UNGUICULATA L. WALP) PASTE FORMULATED WITH SOY FLOUR AND EDIBLE COATINGS

Akara, a popular West African fried food made from dry cowpeas, contains about 31% fat on a dry weight basis. Previous work in our laboratory showed that akara made from a 94% cowpea flour/6% soy flour blend plus edible coatings absorbed 26% less oil during frying than akara made from 100% cowpea. The objective of the present study was to determine the quality and acceptance of modified akara, either freshly fried (one‐stage) or partially fried/frozen/thawed/finish‐fried (two‐stage) as would be employed in the home or a foodservice setting. Soy‐substituted akara was firmer than freshly fried, 100% cowpea (control) akara. Methylcellulose‐coated akara was significantly different in total color from the control. Consumer acceptance studies indicated that, compared with two‐stage fried/100% cowpea akara, the two‐stage fried/6% soy formulation had similar hedonic ratings for flavor, texture, oiliness and overall acceptance. Sensory evaluation also indicated that two‐stage fried/6% soy akara with edible coatings was considered unacceptable (ratings < 5.0).     

SOME TEXTURAL, SENSORY AND NUTRITIONAL PROPERTIES OF EXPANDED SNACK FOOD WAFERS MADE FROM CORN, LENTIL AND OTHER INGREDIENTS

Crisp expanded wafers were produced from extruded pellets containing specialty starches and flours derived from peas, lentils, corn and blends of lentils and corn. The density, hardness and consumer acceptability of the wafers varied with the different ingredients. The most acceptable products were produced from corn, lentils and blends of these two ingredients. The weight, density, stiffness and hardness of the wafers increased with the proportion of lentil flour used to make them. Sensory analysis suggested that consumer acceptability was optimal for blends containing between 40 and 80% of lentil flour. Stiffness and fracture force measured by texture profile analysis were correlated with the sensory attributes of hardness and toughness. The glycemic potential measured by in vitro digestion of the wafers was lower for the 100% lentil wafers compared with the 100% corn wafers because of the amount of starch in the grain. For combinations of corn and lentils, the carbohydrate digestion rate, and hence the glycemic potential, was lower than for either 100% corn or 100% lentil wafers. Blending of selected cereal flour ingredients should be a useful method for reducing the glycemic impact of cooked starchy snacks.     

Protein contents, physical and sensory properties of Nigerian snack foods (cake, chin-chin and puff-puff) prepared from cowpea – wheat flour blends

Some Nigerian snack foods, particularly cake, chin‐chin and puff‐puff, were prepared from blends of cowpea and wheat flours. The snack foods were evaluated for their protein content, physical and sensory characteristics. The latter included colour, flavor, texture and overall acceptability. All the snack foods showed higher protein content when compared with the 100% wheat flour based snack foods. The protein content increased with the increasing levels of cowpea flour in the blend. The physical properties of the supplemented snack foods were not adversely affected by supplementation with cowpea. Similarly, at all levels of cowpea supplementation, the sensory characteristics of the snack foods did not differ significantly (P > 0.05) from those of the 100% wheat flour based snack foods.     

Some Antinutritional Factors in Moringa peregrina (Al-Yassar or Al-Ban) and Soybean Products

Moringa peregrina and soybean defatted flours, protein concentrates, and isolates were assayed for trypsin (TIA) and α-amylase (AIA) inhibitor activities, phytic acid, tannin and chlorogenic acid contents, and in vitro protein digestibility (IVPD). TIA in M. peregrina defatted flour (MDF) was lower (P < 0.05) but more heat resistant than in soybean. AIA in MDF was lower than in soybean and inhibited pancreatic amylase more than bacterial amylase. Some M.peregrina products were higher in phytic acid but lower in chlorogenic acid than soybean. Tannin was low in all samples. IVPD was slightly lower for M.peregrina than for soybean.     

Supplementation of pearl millet flour with soybean protein: effect of cooking on in vitro protein digestibility and essential amino acids composition

In vitro protein digestibility (IVPD) and amino acids profile of pearl millet (Dempy cultivar) supplemented with soybean protein (5–15%) were investigated. Supplementation of dempy flour with soybean protein steadily decreased IVPD with increasing the portion of soybean in the blend. The in vitro protein digestibilities of the cooked supplemented dempy flours were higher when compared with the raw ones, whereas the highest value was that of the 5% soybean protein. All essential amino acids of dempy flour were enriched on supplementation with soybean protein. The levels of amino acids increased with increasing the amount of soybean protein in the blend. Essential amino acids in dempy supplemented with 15% soybean are comparable to those in the FAO reference pattern. Supplementation increased significantly lysine to 1.5–2.4 folds. Essential amino acids content remained higher in the cooked composite flours when compared with the cooked native dempy flour.