Tigernut Flour Research Articles

Proximate, Physical and Sensory Characteristics of Enriched Cake Produced from Wheat and Tiger Nut Flour Blends

Consumers’ attention is shifting towards dietary fiber as more information about its health benefits is unfolding. In Nigeria, owing to the high level of dietary fibre and other inherent nutrients of tigernut, it has been identified as one of the underutilized crops which could be incorporated into cake production. In this study, the effect of substituting tigernut flour for wheat flour on the proximate, physical and sensory properties of cake quality were evaluated. The proximate composition increased with increasing levels of tigernut flour. Crude fibre increased from 1.04 to 2.25%, ashfrom 2.03 to 3.22, crude fat from 4.17 to 7.21 and protein from 10.02-14.53% resulting in a nutritious cake. The physical properties of the cake from the composite flour blends were affected significantly (P ≤0.05) by tigernut substitution. The hardness, cohesiveness, springiness, weight and volume of cakes decreased with increasing tigernut level substitution. Suitable composite cakes which could reduce the incidence of protein-energy malnutrition can be made with up to 20% tigernut flour substitution.

Radio frequency drying on functional diversity of tiger nut flour: Effects on physicochemical, structural, and rheological properties

Tiger nut (TN) is a valuable nutrient and gluten-free tuber. To achieve high-quality TN flour as functional ingredients in food, it is essential to develop effective drying technologies for TN. Five drying methods including natural drying (Control), hot-air drying (HD), radio frequency single drying (RFSD), RF assisted hot-air drying (RFHD), and RF- vacuum drying (RFVD) were selected and compared to determine their effects on physiochemical, structural, and rheological properties of TN flour. Results showed that RF drying (RFD) significantly improved the hydration, oil-absorbing, and antioxidant activity capacity, especially for RFVD. RFHD exhibited greater color (BI = 13.80 ± 0.05 and C = 10.26 ± 0.05) and reducing sugar content (253.50 ± 2.27 mg d.b.) than RFSD and RFVD. The gelatinization temperature, enthalpy value, and particle size (57.30–269.33 μm) of TN flour were reduced. The structural property results indicated that RFD reduced the relative crystallinity and short-range ordering of the flour, altered protein secondary structure, and caused the damaged microstructure in comparison with Control and HD groups. All sample gels exhibited a weak strain overshoot behavior (type III) under large amplitude oscillations, and RFD resulted in a reduced viscoelastic behavior. RFD could be an effective method to produce functional TN flour.

The in-vitro starch digestibility, pasting and antioxidant properties of the composite flour from cassava root and tigernut seed

ABSTRACT This study determines the influence of tigernut flour incorporation into fermented cassava flour on the starch digestibility, functional attributes, pasting behaviour, and antioxidant properties of composite flour. The composite flour formulations are cassava flour to tigernut flour ratios of 90:10, 80:20, 70:30, 60:40, and 50:50 together with 100% fermented cassava flour and 100% tigernut flour as control. The flour samples were evaluated for their functional properties, pasting behaviour, in vitro starch digestibility, total phenolic content, and radical scavenging activity. There was a significant reduction in water absorption capacity (2% to 16%) and swelling capacity (9% to 58%) of the composite flour. The inclusion of tigernut also resulted in reduction in the viscosity of the cassava-tigernut composite blends. However, the composite flours exhibited higher total phenolic content and enhanced radical scavenging activity. Compositing fermented cassava flour with tigernut flour may help improve the health of the consumer when processed.

Functional and Antioxidative Characteristics of Soft Wheat and Tiger Nut (Cyperus esculentus) Flours Binary Blends.

Tiger nut (Cyperus esculentus) or chufa is little known plant of high nutritious content. Popularized by a plant-based drink called "horchata de chufa," it still offers a lot to research, being abundant in fat, starch, fiber and minerals and vitamins. To properly adjust this raw material to new purposes, the knowledge of crucial properties of the most basic blends like with soft wheat flour is needed. This article evaluates the techno-functional, viscometrical and bioactive characteristics of soft wheat:tiger nut blends of 5%, 10%, 15%, 20% and 25%. Granulometry, water-holding capacity (WHC), water absorption capacity (WAC), water absorption index (WAI), water solubility index (WSI), oil absorption capacity (OAC), hydrophilic/lipophilic index (HLI), color, pasting properties, total polyphenol content (TPC), antioxidant activity (DPPH), reducing sugars content and dough-rising capacity were assessed. The addition of tiger nut improved total polyphenol content of blends, however, It was observed that the addition of tiger nuts raised the total polyphenol content of the mixtures, but this was not statistically significant despite as much as 25% of tiger nuts. Oppositely, antioxidant activity was gradually improved with increasing tiger nut content. Pasting properties were impacted by tiger nut addition, lowering both pasting viscosity and trough viscosity, however, final viscosity was not particularly affected, being lowered by less than 15%. The highest water absorption was noted for 100% tiger nut both for WHC and WAC, however, WAI was the lowest for this sample. All the blends with tiger nut revealed improved dough-rising profile.

Development of innovative tigernut-based nutritional snack by extrusion process: effects of die temperature, screw speed, and formulation on physicochemical characteristics

Tigernut (TN) is an underutilized crop with nutritional value that has remained untapped in producing extruded products. This research aims to establish the favorable extrusion conditions that produce a TN-based nutritive extruded snack with improved physicochemical characteristics. A collet extruder was used in this comparison study to examine the effects of formulation (60% TN flour and 40% brown rice [BR] vs. 60% TN flour and 40% Japonica rice [JR]). The effects of extrusion conditions, such as die temperature (90°C, 100°C, and 110°C) and screw speed (250, 300, and 350 rpm), on the physicochemical characteristics of extrudates were studied. TN-BR extrudates produced at 110°C and 350 rpm had the following improved characteristics: protein (6.09–7.33%), ash (1.40–1.59%), crude fat (7.15–9.90%), crude fiber (2.51–3.92%), reduced hardness (2.35–3.37 N), springiness (2.30–2.64), chewiness (234.71–256.72 N), bulk density (1.17–2.57 g/cm3), expansion ratio (1.65–2.24), color (L*: 68.86–74.30), water absorption index (2.69–3.45 g/g), water solubility index (13.95–21.75%), and oil absorption capacity (23.65–25.64 g/g). Extrudates produced at lower temperatures (90°C and 100°C) and screw speed (250 and 300 rpm) exhibited lesser surface consistency than the extrudates produced at 110°C and 350 rpm. The antioxidant activity and the total phenolic content (40.91–49.63 mg gallic acid equivalent/100 g) were improved significantly. Similar improvements were observed in TN-JR extrudates; however, TN-BR extrudates had better nutritional value (higher protein: 7.33%, higher ash: 1.59%, and higher antioxidant activity). The results could help with economic success, food nutrition improvement, and food security by exploiting the underutilized TN crop for sustainable extruded snacks production.

Defatted tigernut flour as a novel substitute for wheat flour: impact on physicochemical and rheological properties during frozen dough storage

SummaryThis study analysed the impact of adding different amounts (5–25%) of defatted tigernut flour (DTF) to frozen wheat dough at different freezing periods. The chemical composition and freeze–thaw stability of the composite flour, as well as the physicochemical properties (e.g., textural, tensile, and rheological properties) of the dough after being frozen, were assessed. It was found that the addition of DTF enhanced the nutritional value of the dough and improved quality characteristics such as texture and tensile properties of the dough after it had been frozen and thawed. With increasing DTF, the content of dietary fibre (8.69–9.63%) and ash (0.54–1.05%) increased significantly, but the content of starch (58.56–54.96%) and protein (11.03–10.35%) decreased as compared to that of wheat flour alone. The thermal and freeze–thaw stability of composite flour was greatly improved with increasing amounts of DTF, and the retrogradation of the dough was delayed. DTF (5–15%) proportionately delayed deterioration of springiness and retarded hardening of the frozen dough. In addition, the extensibility of the frozen dough was significantly increased by adding 10–25% DTF. The results suggest that DTF has the potential to positively influence the quality of frozen wheat dough, while at the same time increasing the high‐value utilisation of tigernut.

Proximate, Physical and Sensory Characteristics of Enriched Cake Produced from Wheat and Tiger Nut Flour Blends

Proximate, Physical and Sensory Characteristics of Enriched Cake Produced from Wheat and Tiger Nut Flour Blends

Quality attributes of cookies from wheat, lima bean and tigernut composite flour

Cookies are widely consumed throughout the world especially among children. They are ready-to eat, convenient and inexpensive food products, containing digestive and dietary principle of vital importance. This study investigated the quality attributes of cookies from wheat, lima beans and tigernut composite flour. Wheat flour was blended with lima beans and tigernut flour at the ratios of 90:5:5, 85:10:5, 80:15:5, 75:20:5 and 70:25:5, respectively. The flour blends were analysed for proximate, functional and pasting properties while the cookies produced from the blends were analysed for anti-nutritional, colour and sensory properties using standard laboratory procedure. Data obtained were subjected to analysis of variance, and mean values were separated using Duncan’s multiple range test. The moisture content, crude fat, crude protein, total ash, crude fibre and total carbohydrate ranged from 8.09%-10.82%, 4.24%-5.58%, 7.04%-8.08%, 1.65%-2.10%, 3.06%-3.48% and 72.68%-73.10%, respectively. Increase in lima bean substitution led to increase in bulk density, water absorption capacity, oil absorption capacity, swelling capacity except solubility index. Significant differences were observed in the pasting properties of the flour blends. Phytate and tannin content of the cookies ranged from 0.574-0.634% and 0.168-0.231% while range of values for lightness, redness and yellowness of cookies were: 38.82-40.04, 6.90-7.96 and 16.26-18.26, respectively. However, cookies prepared from blend of 70% wheat flour, 25% lima bean and 5% tigernut flour were the most preferred in terms of overall acceptability.

Structure, nutritional composition, and functionality of xylanase/microwave radiation-pretreated tiger nut.

In this study, tiger nut was pretreated with xylanase (Xyl), microwave radiation (MW), and a combination of both (MW + Xyl). The structure, nutritional composition, technofunctional, and antioxidant properties of the pretreated and untreated (control) tiger nut flour (TNF) were investigated. The Fourier transform infrared spectroscopic and X-ray diffractrometric spectra of the control and the pretreated samples are similar; however, there was a slight change in some peaks in the pretreated samples, indicating structural re-organization of macromolecules. Scanning electron microscopic images show reductions of surface erosion and formation of clusters in the MW + Xyl-treated TNF compared to the other pretreated samples. Pretreatment increased the protein, Ca, total phenolic content, and swelling capacity of TNF by 3.71-7.31%, 29.41-32.35%, 4.39-9.65%, and 1.59-6.75%, respectively. Meanwhile, 45.52-58.78% and 11.54-15.38% reductions in fat content and water absorption capacity, respectively, were recorded. Pretreatment of TNF with Xyl and MW + Xyl increased its soluble dietary fiber by 26.84% and 64.34%, respectively; however, a 3.31% reduction was recorded following MW treatment. The highest 2, 2-diphenyl-1-picrylhydrazyl scavenging activity (53.20%) was recorded in the MW + Xyl-treated TNF. These findings proved that pretreating TNF with microwave radiation and Xyl could improve its technological and nutritional qualities, enhancing its applicability in food systems.

Nutritional quality and physicochemical properties of biscuit from composite flour of wheat, African yam bean and tigernut

This study investigated the effect of the supplementation of wheat flour with flour blends of African yam bean (AYB) and tigernut for the production of biscuits and evaluated the sensory characteristics. The composite flours were of ratio 70:25:5 (TWB), 70:20:10 (ATW), 70:15:15 (BTT) for wheat: AYB: tigernut, respectively, while 100 % wheat flour served as control (WTY). The composite flour samples were analyzed for proximate, functional and pasting properties. The physical and chemical properties and sensory attributes of the developed biscuits were carried out. The moisture, protein, fat, ash, crude fiber, carbohydrate, and energy contents of the composite flour ranged from 6.63 to 8.13 %, 11.22–18.36 %, 13.27–19.15 %, 0.98–0.99 %, 3.96–7.43 %, 59.97–62.55 % and 400.89 to 410.40 Kcal/100g, respectively. The results showed that protein fat, ash and crude fiber of the biscuit were improved. The water and oil absorption capacity of composite flour was low while the pasting properties of the composite flour blends reduced as the AYB flour increased. All the composite flour blend biscuit samples possessed high essential nutrients and antioxidant potential. All the biscuits samples were accepted by the panelists, however, sample BTT (70 % wheat flour+15 % AYB flour+ 15 % tigernut flour) was most accepted in appearance, aroma, taste, crispness and overall acceptability. Therefore, biscuits from the flour blends of wheat, AYB and tigernut could be nutritionally beneficial and good for adults.

Impact of tiger nut flour as a prebiotic and thickener agent on bio-yoghurt drink

Impact of tiger nut flour as a prebiotic and thickener agent on bio-yoghurt drink

Tracing tiger nut (C. esculentus L.): functional food from the colossal Cyperus genus

Tiger nuts (also called earth almonds or chufa) are the stolons of the sedge Cyperus esculentus L. and have been traditionally used as food or as an additive to drinks such as horchata de chufa. Recently, chufa experienced a hype as functional food because of its richness in dietary fiber and as a source of unsaturated fatty acids. Its close relative, nutgrass (Cyperus rotundus L.) has similarly long history of human use, but rather for medical purposes, due to a high content of secondary compounds. Both species are invasive weeds responsible for high yield losses in crop plants, especially in Southeast Asia, Africa, and subtropical America. They are not easily discerned, occur together, and are both traded under similar or identical vernacular names. For the purpose of consumer protection, it is important to discriminate them in commercial samples, which is not trivial by morphological markers and often impossible since they are mostly used in highly processed form. Therefore, a molecular authentication assay was developed using taxonomically authenticated plants as reference material. The plastidic marker psbA-trnH igs (intergenic spacer) and the nuclear marker Internally Transcribed Spacer were used for barcoding. To develop a sequencing-free fingerprinting assay, a single-nucleotide polymorphism in the ITS2 region could be employed to discriminate C. esculentus from its possible adulterant C. rotundus by a tailored Amplificatory Refractory Mutation System PCR. This approach was successful both, in reference to plants, as well as in highly processed commercial products such as tiger nut flour. We show that by a single PCR we can detect surrogation by nutgrass down to a threshold of 10% in tiger nuts as contribution to safeguard product authenticity against possible adulterations in a growing global market.

Sensory optimization of an instant brown rice cereal containing tigernut and soybean

The aim of this study was to determine the optimum ingredient formulation for an instant rice-based cereal enriched with tigernut and soybean flours. An extreme vertices design involving three (3) components (brown rice flour, tigernut flour and soybean flour) was used. A slurry of the three (3) was dried on a single drum dryer at 120 °C and 5 rpm. Mixture regression modeling was used to assess the impact of each component on the functional quality and sensory attributes properties of the drum dried product. Graphical optimization of the formulation was performed by superimposing contour plots of individual sensory attributes examined. Predicted regression models showed that tigernut flour, followed closely by rice flour, had the largest effect on overall acceptance of the product. The optimum formulation for an acceptable drum dried product was determined to be rice flour – 46.6 %, tigernut flour – 39.1 % and soybean flour – 14.3 %. The product was stable during storage, as only marginal increment was recorded in the quality attributes assessed. This study provides an avenue for enhancing the utilization potential of both brown rice and tigernut.

Process optimization of extrusion process variables for improving the quality and extrudate characteristics of wheat-tiger nut pasta

Tiger nuts are underexploited crops with essential potential that remains untapped with capability to be a better alternate for wheat flour in pastry industries. This research evaluates the effect of extrusion variables on the quality and extrudate characteristics and sensory acceptability of wheat-tiger nut pasta. Tiger nut flour was substituted with wheat flour at 0, 10 and 20%. A Box-Behnken experimental design with three independent variables; feed composition (80:20, 90:10 and 100:0%), moisture content (5, 10 and 15%, wb) and barrel temperature (60, 70 and 80 °C) were used and these resulted in a total of 17 experimental carried out to produce extruded pasta. Results showed that feed composition enhances and increased the ash, protein, fibre and carbohydrate contents of the pasta, while increase in barrel temperature resulted in low fat content. High feed composition and low feed moisture content resulted in high bulk density, water and oil absorption capacities and swelling capacity of wheat-tiger nut pasta. The residence time, mass flow rate and expansion ratio progressively increased with a rise in feed composition, feed moisture content and barrel temperature. The responses models gave good fit with R2> 0.90, which indicate the adequacy of the models to predict closely the experimental data. However, the optimization of combined effects of extrusion variables was achieved with 80% wheat and 20% tiger nut flour containing 15% feed moisture content extruded at 70 °C temperature. These variables are critical in commercial production of improved high quality wheat-tiger nut pasta.

Effects of sprouting duration on the nutrient, functional, and phytochemical properties of tiger nut flour, and the sensory properties of bread made thereof.

The influence of sprouting on tiger nut's (TN) nutritional, functional, and phytochemical quality was examined, and the flour used for bread making to evaluate the feasibility as a functional ingredient. TN was sprouted and sampled at 3 days intervals for 12 days, dried and milled into flour and analyzed. Subsequently, 25% of wheat flour (WF) was replaced with the 9 days-sprouted TN flour for bread. Sprouting for 9 days increased the protein content from 9.19±0.04 to 9.79±0.15g/100g dry matter (DM), fiber from 6.75±0.16 to 9.27±0.44g/100g DM, and ash from 2.34±0.10 to 2.70±0.06g/100g DM but decreased fat content from 26.10±0.18 to 23.18±0.43g/100g DM and soluble sugar from 33.13±1.25 to 23.75±1.44°Bx. We observed increases in the polyphenols (94.16±6.43-214.23±6.98mg GAE/100g) and ascorbic acid (26.66±0.17-65.13±0.19mg AE/100g) and decreases in the cyanogenic glycosides (273.79±0.37-231.54±3.53mg/100g) and oxalates (19.04±1.14-5.65±0.93mg/100g) contents. Sprouting decreased the particle size and increased the water retention and swelling power of TN flour. WF bread was described as stretchy, sweet, and creamy, whereas sprouted TN bread was brown, nutty, and wheat-like. Consumer acceptance for the sprouted TN bread was comparable to WF bread, showing the possible application in bread making. PRACTICAL APPLICATION: The outcome of the study could help to exploit the nutri-functional and phytochemical benefits of sprouted TN in the baking industry for producing acceptable products. This would enhance the utility of TN for food in regions where TNs grows.

Rheological and quality properties of tiger nut containing biscuit dough baked in IR-MW combination oven.

The effects of replacing part of the rice flour (RF) with tiger nut flour (TNF) were studied in gluten-free biscuits. A control biscuit dough containing RF only and 5 formulations containing 10, 20, 30, 40, and 50 % tiger nut flour on a flour basis (10TNF, 20TNF, 30TNF, 40TNF, and 50TNF) were prepared. The rheological and quality properties of biscuits baked both in conventional and infrared-microwave combination (IR-MW) ovens were determined. The rheological results showed that as the TNF ratio increased, G', G" and ƞ* decreased due to the high oil and dietary fiber content of the TNF. Texture analysis results showed that control dough and biscuits showed harder texture because of the damaged starch content of RF. Damaged starch also affected the spread ratio of the biscuits adversely. Weight loss of the biscuits baked in the IR-MW oven was higher than the ones baked in the conventional oven since higher inside pressure occurred in the dough. The color of the conventional baked biscuits was darker than IR-MW baked ones due to the greater extent of Maillard Browning. As the TNF ratio increased, darker biscuits were obtained since TNF has a high amount of sugar, and also its natural color is brown. Given the excellent nutritional and product quality impacts of TNF, it would be appropriate to use it as a raw material substitute in gluten-free biscuits. Furthermore, IR-MW baking was shown to be an appropriate method for biscuit quality when compared to conventional baking. This article is protected by copyright. All rights reserved.

Quality Attributes of Wheat-Tigernut Flour Blends and Chin-Chin Produced From the Blends

This study evaluated the physicochemical, functional and proximate composition of wheat and tigernut composite flour; and proximate composition and sensory properties of Chin-chin produced from the wheat-tigernut flours blends. The addition of tigernut flour to wheat was 10, 20, 30 and 40% representing sample A – D while 100% wheat flour (sample E) served as control. Analyses were by standard analytical procedures. pH, titratable acidity and viscosity of the flour samples ranged from 4.03 - 4.37, 0.39 - 0.80 %Lactic acid, and 9.38 - 9.58 Pa.s respectively, while sugar was 1.00 0Brix across all samples. Oil absorption capacity, water absorption capacity, dispersibility, solubility index, swelling power, bulk density and foaming capacity varied respectively from 1.22 - 1.40 g/g 1.14 - 1.34 g/g, 2.00 - 4.13%, 35.00 - 37.00 g/g, 6.45 - 7.48 g/g, 0.83 - 0.90 g/ml and 5.00 - 20.00%. Proximate composition of the flour blends varied respectively, from 5.55 - 8.79, 9.28-18.36, 2.12 - 10.91, 1.70 - 2.01, 1.31- 4.17 and 64.78-74.06% for moisture, protein, fat, ash, crude fibre, and % carbohydrates. While energy value of the flours ranged from 351.89 - 405.32 kcal/100g. Chin-chin had moisture, protein, fat, ash, crude fibre, carbohydrate and energy contents of 1.85 - 8.64, 10.06 - 16.18, 24.25 - 34.29, 1.20 - 1.70, 14.65 - 27.42, 20.79 - 41.65% and 418.03 - 493.27 kcal/100g respectively. Assessor’s degree of likeness for the chin-chin ranged from 2.85 - 7.15, 3.56 - 7.85, 3.05 - 6.60, 3.25 - 7.10, 3.65 - 8.00 and 3.06 - 7.26 respectively, for aroma, appearance, colour, crunchiness, taste, and overall acceptability. Tigernut inclusion led to a significant (p<0.05) increase in ash, fibre and carbohydrate while moisture decreased. Chin-chin from sample A with 10% tigernut flour had the highest degrees of likeness followed by sample B with 20% tigernut flour. For diversification in the use of tigernut flour, the inclusion of up to 20% can be recommended for full application in the baking industry.

Influence of Partially Substituting Wheat Flour with Tiger Nut Flour on the Physical Properties, Sensory Quality, and Consumer Acceptance of Tea, Sugar, and Butter Bread.

Tiger nut is a valuable source of fiber, lipids, minerals, and carbohydrates. However, avenues for incorporating tiger nuts into food remain underexplored, especially in several tropical countries where the plant grows well. The current study investigated the effects of partially substituting wheat flour (WF) with tiger nut flour (TNF) on the physical and sensory properties of different bread types to evaluate the more amenable system for tiger nut incorporation. The substitution was done at WF:TNF ratio of 100 : 0, 90 : 10, 85 : 15, 80 : 20, 75 : 25, and 70 : 30 for butter bread (Bb), tea bread (Tb), and sugar bread (Sb). The results show that WF substitution with TNF increased bread brownness and color saturation and decreased lightness, showing the highest impact on Sb, followed by Tb and Bb. Additionally, bread-specific volume decreased significantly after 20% (Bb), 25% (Tb), and 30% (Sb) TNF substitution. Furthermore, substituting WF with 30% TNF increased crumb hardness from approx. 1.87 N to 3.64 N (Bb), 3.46 N to 8.14 N (Tb), and 6.71 N to 11.39 N (Sb) and caused significant increases to 17.80 N (Tb) and 21.08 N (Sb) after 3 d storage. Only a marginal effect on storage hardness (4.32 N) was observed for Bb. Substituting WF with 10% TNF for Bb or 25% TNF for Tb led to significantly higher consumer (N = 56) scores for all attributes and overall acceptability. However, no significant effect on the overall acceptability of Sb was observed. Flash profiling showed frequently used descriptors for Bb as firm, moist, buttery, smooth, and astringent. After 10% TNF substitution, descriptors were chewy, firm, sweet, porous, dry, and caramel, and that of 30% TNF were grainy, chocolate, brown, nutty, and flaky. Substituting WF with TNF increased the lipids, fiber, and minerals content but decreased the protein and carbohydrate contents of bread. TNF substitution led to different physical and sensory effects depending on bread type, showing that Bb with 10% or Tb with 25% TNF is more comparable with the overall acceptance quality of 100% WF. The study is relevant for utilizing tiger nuts as an ingredient in bread products.

Quality Evaluation of Bread Prepared from Wheat-Chufa Tuber Composite Flour.

The oil amounts of breads were measured between 0.13% (control) and 4.90% (with 40% 6 chufa). The total phenolic and flavonoid contents of the breads enriched with chufa tuber flours (powders) were reported as between 37.42 (control) and 99.64 mg GAE/100 g (with 20% chufa) to 61.19 (control) and 120.71 mg/100 g (with 20% chufa), respectively. The antioxidant activities of the bread samples were recorded as between 0.20 (control) and 3.24 mmol/kg (with 20% chufa). The addition of chufa flour caused a decrease in L* values of breads with the addion of tigernut flour. Oleic and linoleic acid contents of the oils extracted from the bread samples enriched with chufa tuber powders were identified as between 61.88 (control) and 66.64% (with 40% chufa) to 14.84% (with 40% chufa) and 17.55% (control), respectively. As a result of the evaluation of sensory properties of breads made from pure wheat flour and composite flours containing 10%, 20%, and 40% chufa tuber flour, the best result was obtained in bread fortified with chufa powder at a concentration of 40%, followed by concentrations of 20 and 10% in decreasing order.

FUNCTIONAL, PASTING AND SENSORY PROPERTIES OF COMPLEMENTARY FOOD FROM ORANGE FLESHED SWEETPOTATO- ROASTED AFRICAN YAM BEAN-TIGERNUT COMPOSITE FLOUR USING RESPONSE SURFACE METHODOLOGY

This study investigated the functional, pasting and sensory properties of complementary food from blends of orange fleshed sweet potato, roasted African yam bean and tigernut composite flour using response surface methodology. Orange fleshed sweetpotato root, roasted African yam bean and tigernut seed were blended into composite flours based on D-optimal mixture design resulting into fourteen experimental runs. The Orange fleshed sweetpotato, roasted African yam bean and tigernut flour blends were analyzed for their functional and pasting properties using standard laboratory procedures. The composite flours were optimized using D-optimal of the mixture design. The optimized composite flours were used to prepare complementary food and sensory properties (taste, colour, aroma, thickness and overall acceptability) were evaluated using nine point Hedonic scale of preference. The bulk density, water absorption capacity, swelling power, dispersibility, least gelation capacity and wettability ranged from 0.82-0.85g/ml, 300.00-359.00%, 6.00-6.51%, 60.20-65.99%, 2.72-3.69% and 22.71to 40.81% respectively. Significant differences (p<0.05) were observed in the pasting properties of orange fleshed sweetpotato, roasted African yam bean and tigernut flour blends. However optimized complementary prepared from the different composite flours were all accepted by the panelists except complementary food prepared from 82.95% orange fleshed sweetpotato, 10.26% roasted African yam bean and 6.78% tigernut composite flour blend.