Increase In Level Of Substitution Research Articles

Low-carbon UHPC with glass powder and shell powder: Deformation, compressive strength, microstructure and ecological evaluation

Waste glass and shells are by-products generated in the production process of the construction industry and aquaculture respectively. The high-value treatment of these materials presents a global challenge. Converting waste glass and shells into solid waste-based ultra-high performance concrete (UHPC) mixtures is an eco-friendly strategy. In this study, glass powder (GP) and oyster shell powder (OSP) were mixed to prepare composite supplementary cementitious materials (GOS) and partially replace cement. The compressive strength, drying shrinkage, microstructure, and environmental impact of GOS-containing UHPC were investigated. Results indicate that adding GOS reduces the fluidity of UHPC mixtures, with further decreases as GOS content increases. Replacing cement with an appropriate amount of GOS (10 wt%-20 wt%) enhances the compressive strength of UHPC, though higher GOS levels reduce its strength. Meanwhile, the drying shrinkage deformation of UHPC decreases significantly as the GOS substitution level increases. The 28-d drying shrinkage deformation of the specimen added with 20 wt% GOS is 574 μm/m, which is 61.96 % lower than the control group. Additionally, the specimen added with 20 wt% GOS shows significantly improved compactness and enhanced bonding at the interfacial transition zone. Compared with traditional UHPC, GOS-containing UHPC has lower carbon emissions and costs, effectively utilizes waste, and promotes sustainable development.

Evaluation of baking qualities, functional and physicochemical properties of wheat supplemented with cassava and mung bean flour blends for bread making

AbstractThe present study evaluated the baking qualities and physicochemical properties of bread produced from wheat flour supplemented with cassava and mung bean flour blends at different levels of inclusion to assess its suitability to be used in bread production. Standard methods were used to carry out the baking qualities and physicochemical properties of the flour blends while 20 semitrained panelists were recruited for the sensory evaluation. The result showed that the gluten content of the flour blends ranged from 3.61% to 24.19%. Sample A (90% wheat:5% cassava:5% mung bean) flour blend had the highest gluten content while sample D (60% wheat:20% cassava:20% mung bean) flour blend recorded the lowest value of gluten content. The viscosity of the flour blends was found to decrease significantly (p ≥ 0.05) with an increase in temperature while the functional properties of the flour blends and physical properties of the bread varied among samples. Sample B (80% wheat:5% cassava:5% mung bean) was found to be highest in bulk density, loaf volume, and specific volume with values 0.73 g/mL, 7.86 cm3, and 0.05 cm3/g, respectively, with enhanced baking quality. Results of the chemical composition showed that fiber and protein content increased with an increase in substitution levels. Sample D had the highest value 0.43% and 27.65% while sample E (100% wheat) had the lowest value 0.38% and 12.60% for fiber and protein content respectively. Carbohydrate content decreased with an increase in substitution levels. Sample E had the highest value 48.88% while sample D had the lowest value 25.32%. Values for moisture, ash, fat, crude fiber, and energy content varied among samples and substitution levels. Sensory evaluation of the various attributes rated on 9 points hedonic scale showed a decrease in the mean score as the level of substitution increased. Sample E was rated high in all sensory attributes and was also found to be significantly different (p ≥ 0.05) among samples although in general acceptability sample E was found to be the same as sample A. The result showed that bread made from 90% wheat:5% cassava:5% mung bean flour blend (sample A) compare favorably with bread made from 100% wheat flour (control) but in baking quality sample B was found to be the best.

Gadolinium manganites substituted with barium Gd1−XBaXMnO3 (x = 0.0; 0.15; 0.18; 0.25): Structural transitions, microstructure, magnetic and electrical properties

The effect of gadolinium substitution by barium on the crystal structure, microstructure, magnetic and electrical properties of Gd1−XBaXMnO3 (x = 0.0; 0.15; 0.18; 0.25) prepared by the solid-state reaction method has been studied. An increase in the concentration of barium to x = 0.18 leads to a critical decrease in the concentration of Mn3+ ions involved in the distortion mechanism and changes in the structural order (Jahn-Teller transition). The porosity of the samples increases and average the grain size and decreases as the concentration of barium increases. The electrical conductivity of Gd1−xBaxMnO3 increases up to 1.5 times compared to the initial material when the concentration of barium increases to x = 0.25. All manganites have TN = 42 K. The Curie temperature increases and changes the sign from negative to positive as the substitution level increases. For the first time, a phase diagram of the evolution of structural, magnetic and electrical properties when replacing Gd with Ba is presented. The evolution of magnetic and electrical properties of manganites is associated with structural distortions of the crystal lattice caused by the substitution of gadolinium with barium.

Sustainable cementitious material with ultra-high content partially calcined limestone-calcined clay

The application of calcined clay and limestone powder in cementitious materials to partially substitute ordinary Portland cement is regarded to be highly potential for developing sustainable green building materials. However, with the increase in substitution level, the major drawbacks include the slow development of the early strength and the decrease of the later strength. In this study, the limestone is partially calcined to form the core–shell structure with loose calcium oxide on the outside and dense calcium carbonate on the inside, and sustainable cementitious material with ultra-high content partially calcined limestone and calcined clay (substitution level is up to 80%) is developed. It is evident from this study that the core–shell structure of partially calcined limestone promotes the formation of a dense layer of hydration products. The incorporation of partially calcined limestone exhibits significant advantages in enhancing the reaction of calcined clay and improving the strength development of the cementitious materials that are 90% and 137% higher than that with the limestone-calcined clay at 7d and 28d, respectively.

Application evaluation of linseed oil as a substitute for fish oil in the commercial diet for juvenile Portunus trituberculatus

Vegetable oil (VO) is increasingly replacing fish oil (FO) in the commercial diet of crustaceans, partly due to a global shortage of FO. But little is known about how different amounts of substitution affect the health and metabolism of crustaceans. A six-week feeding trial was conducted to evaluated the effects of different replacement levels of FO with linseed oil (LO) on growth performance, antioxidant and digestive capacity and fatty acid metabolism in swimming crab, Portunus trituberculatus. Five isonitrogenous and isolipidic diets (480 g kg−1 protein and 120 g kg−1 lipid) were formulated to contain graded levels of LO, and FO was replaced with LO at 0%, 25%, 50%, 75% and 100%, respectively. The results showed that 50% of FO could be replaced by LO without affecting the growth performance and feed utilization for juvenile swimming crab. In hemolymph, 100% dietary replacement of FO with LO, the activities of alanine aminotransferase (ALT) and aspartate transaminase (AST) exhibited significantly higher than those fed the other diets, the concentrations of triacylglycerol (TAG), total cholesterol (T-CHO) and high-density lipoprotein cholesterol (HDL-C) significantly increased with increase of dietary replacement of FO with LO, which may lead to hyperlipidemia in swimming crabs. The number of R cells and their lipid droplets in hepatopancreas gradually increased with increase of replacement of FO with LO, the results confirmed the occurrence of lipid accumulation in the hepatopancreas. The activities of glutathione (GSH), and glutathione peroxidase (GPX) in hepatopancreas significantly decreased with increase of replacement of FO with LO, and crabs fed diet with 50% replacement of FO with LO had higher activities of trypsin and lipase (LPS) than those fed the other diets. Long-chain polyunsaturated fatty acids (LC-PUFA), n-3/n-6 PUFA in hepatopancreas and muscle significantly decreased with the increase of substitution level of FO with LO. Moreover, the expression of genes related to LC-PUFA synthesis as well as fatty acid β-oxidation, such as elongase 4 (elovl4), hepatocyte nuclear factor 4-α (hnf4α), retinoid X receptor (rxr), carnitine palmitoyltransferase 2 (cpt2) and acyl-CoA oxidase (acox2), were down-regulated with increase of dietary replacement of FO with LO. In conclusion, it is suggested that the optimal substitution ratio of LO for FO should be less than 50% in the diet of Portunus trituberculatus.

Performance Enhancement of Sustainable Cementitious Material with Ultrahigh Content Limestone and Calcined Clay

Calcined clay can be combined with limestone to partially substitute cement for developing the sustainable cementitious material. However, an increase in substitution level beyond a certain range limits the compressive strength development. This study proposes to increase the substitution level of calcined clay and limestone to an ultrahigh level (as much as 75%) by optimally adding portlandite and gypsum. First, the reactivity of calcined clays with different kaolinite contents is explored by mixing the clay with different amounts of portlandite. A linear relationship is obtained between the kaolinite content of the calcined clay and the amount of portlandite such that optimal activation effect is achieved. Based on the optimum dosage, external portlandite is mixed to enhance the performance of cementitious material with ultrahigh content limestone and calcined clay. The addition of an appropriate amount of portlandite is beneficial to the continuous reaction of the calcined clay, refining the pore structure and significantly improving the 28 d compressive strength. Then, different amounts of gypsum are added to further enhance the mechanical properties of cementitious material with ultrahigh content limestone and calcined clay. The amount of gypsum equal to 30% of the calcined clay in the system could effectively improve the compressive strength in the early stage (3 and 7 d). The performance of cementitious material with ultrahigh content limestone and calcined clay is significantly enhanced by the synergistic effect of portlandite and gypsum, as revealed by the improvement in compressive strength and microstructure.

Proximate, functional and sensory evaluation of cake produced from composite mixture of African locust bean fruit pulp (Parkia biglobosa) flour and wheat flour.

Cake was produced using blends of wheat flour and African locust bean fruit (Parkia biglobosa) pulp flour to assess the suitability of the locust bean fruit pulp flour in baking cake of higher nutritional value. The proximate, functional and sensory qualities of the cake samples produced were investigated. The flour used was made from composite blends of wheat flour and African locust bean fruit pulp flour in varying proportions (100:0, 80:20, 60:40, 40:60 and 20:80). The cake produced from 100% wheat flour served as control, and the flour blends were also analyzed for their functional properties. The results showed that there was a significant increase in moisture, ash and crude fibre as the amount of African locust bean fruit pulp flour increased, while the protein, crude fats and carbohydrate content decreased. The moisture content ranged from 4.40 - 6.92 %, ash (1.51 - 2.18 %), and fibre (1.11 - 2.32 %). The functional properties of the flour varied as the substitution level increased. An increase was observed in the oil absorption capacity (1.19 to 2.42 g/mL), bulk density (0.25 – 0.65 g/mL), water absorption capacity (1.18 – 1.60 g/mL) and the loose density (0.08 – 0.37 g/mL). On the other hand, a decrease was observed in the gelation temperature (72.10 – 68.10 oC) and the swelling index (1.55 – 1.40 g/mL). The result of sensory attributes were evaluated using 9 point hedonic scale with a mean value of appearance ranging from 6.68 - 8.50, taste (6.82 - 8.28), texture (6.69 - 8.05), and the flavour (6.33 - 7.67). The overall acceptability value ranged from 7.38 to 8.52. The results showed that there was a significant difference at P<0.05 between the control and samples with increase in level of substitution in all the parameters investigated. Hence, acceptable cake can be produced from a composite substitute of 80:20 for wheat flour and African locust bean fruit pulp flour.

Effect of freeze‐dried kinnow peel powder incorporation on nutritional, quality characteristics, baking, sensorial properties, and storage stability of traditional wheat‐based soup sticks

Nutritional, techno-functional, and sensorial properties of soup sticks enriched with freeze-dried kinnow peel powder (FDKPP) were investigated. The increase in substitution level of FDKPP in wheat flour from 0 to 9% led to a significant increase in ash content, visco-elasticity, breaking strength, yellowness, and baking and storage stability and decline in the moisture, crude protein, crude fat, pasting parameters, physical parameters, L* (lightness), and a* (redness) values. Furthermore, FDKPP enriched soup sticks showed digestion time higher than control soup sticks and analysis of appearance and structure showed a decrease in pore size. Analysis of baking and storage stability revealed the enrichment of FDKPP with polyphenols. The sensory evaluation revealed that increasing the replacement level had a positive effect on the intensity of aroma and color, but had a negative effect on taste. Novelty impact statement The kinnow peels, which are typically discarded as waste, could be used to enrich wheat-based soup sticks. The study revealed that incorporating freeze-dried kinnow peels could develop improved soup sticks with promising effects on nutritional, technological, and sensory aspects. The efficient use of this citrus waste as a novel bioactive food ingredient can have a promising effect in addressing the concerns such as industrial waste management and food security.

Effects of Dietary Inclusion of Clostridium autoethanogenum Protein on the Growth Performance and Liver Health of Largemouth Bass (Micropterus salmoides)

Clostridium autoethanogenum protein (CAP) is a novel protein source for aqua-feeds. The present study aimed to investigate the effects of dietary CAP on growth performance, immunity, and liver health status of juvenile largemouth bass (Micropterus salmoides). Four isonitrogenous and isolipid experimental diets were formulated to replace 0% (D1, control), 25% (D2), 50% (D3), and 75% (D4) of fish meal by CAP. Fish (15.05 ± 0.08 g) were randomly fed one of four experimental diets for 8 weeks. The results showed that weight gain (WG), specific growth rate (SGR), feeding rate (FR), viscerosomatic index (VSI), and hepatosomatic index (HSI) of the D4 group were significantly lower than D1, D2, and D3 groups (P < 0.05). With the increase of substitution level, the total antioxidant capacity (T-AOC) of liver tissue was significantly decreased, while the plasma alkaline phosphatase (AKP) activity was significantly increased (P < 0.05). Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were significantly higher in D3 and D4 groups than in D1 and D2 groups (P < 0.05). Replacing 50 or 75% fish meal by CAP significantly induced the transcription level of apoptosis-promoting genes (bcl-2-associated death protein [bad] and bcl-2-assoxicated × protein; bag [bax]), anti-apoptosis-related genes (tumor protein 53 [p53] and b-cell lymphoma-2 [bcl-2]), and the apoptotic Caenorhabditis elegans (C. elegans) death gene-3 like caspases (cysteine-aspartic proteases-3 [caspase-3], cysteine-aspartic proteases-8 [caspase-8], cysteine-aspartic proteases-9 [caspase-9], and cysteine-aspartic proteases-10 [caspase-10]) in liver, while suppressed the gene expression of the inflammatory factors [interleukin-1β (il-1β), interleukin-8 (il-8), and tumor necrosis factor, tnf ] in head kidney. At the same time, dietary inclusion of CAP elevated the protein expression of bcl-2, autophagy microtubule-associated protein light chain 3A/B (LC3A/B-I), and LC3A/B-II by inhibiting the phosphorylation of the mammalian target of rapamycin (mTOR; P < 0.05). Moreover, the apoptosis rate of the D3 and D4 groups was significantly increased (P < 0.05). Taken together, these results indicated that the optimal level of CAP-replacing fish meal should be <50% that has no negative effect on the growth performance and liver health of juvenile largemouth bass. In addition, excessive CAP inclusion may damage liver health by activating autophagy and apoptosis signaling pathways.

Technical and economic potentials of the unconventional extruded dried Arabic bread wastes in broilers diets.

Food waste is one of the major global challenges that have adverse socioeconomic and environmental impacts. Therefore, studying food waste utilization potentials and minimizing its negative consequences becomes imperative. This study aims to assess the technical and economic potentials of substituting corn with unconventional extruded dried Arabic Bread waste (EDABW) in broilers’ diets, in terms of broilers’ performance, carcass characteristic, economic net returns, and income over feed cost (IOFC). One hundred eighty unsexed one-day-old broiler birds of Ross breed were distributed randomly in six treatments (0, 20, 40, 60, 80, and 100% EDABW group) of isocaloric and isonitrogenous diets in a completely randomized design with six replicated (5 chicks/replicate). The investigated traits were broilers’ performance (live body weight, total feed intake, total feed conversion ratio, and total weight gain. Other traits such as carcass weight, abdominal fat, edible offal (liver, heart, and gizzard), eviscerated (breast muscles, drum and thigh muscles, and wings) were weighed and expressed based on a live body weight. Results showed that the 20% replacement level of corn with EDABW generated the highest increase in the live body weight and the eviscerated carcass at about 4.24% g and 4.90%, respectively. On the other hand, the economic analysis showed potential reductions in the broilers’ diet cost and the total broilers' production cost as the levels of corn substitution with by unconventional EDABW increased. The reductions were estimated at 5.1%, 6.3%, 8.4%, 9.3%, and 9.9% at substitution levels of 20%, 40%, 60%, 80%, and 100%, respectively as compared to the control diet. The results also showed a potential increase in the net economic returns of broiler meat as the increase in substitution levels ranged between 3.5–06.8% and 4.3–8.3% as compared to the control diets using the average retail and wholesale prices of broiler meats, respectively. In addition, the maximum IOFC was estimated potentially at a 20% substitution level of corn with EDABW. Conclusively, the study results show promising technical and economic potentials for unconventional EDABW in broilers’ diets that could lead to a thriving industry of unconventional broilers’ diets with high net economic returns and maximum IOFC.

Effect of Supplementation of Amaranth Flour on Various Quality Attributes and Antioxidant Activities of Bread

Background:The present investigation was carried to develop amaranth based wheat flour bread. Products were developed by using different levels of amaranth flour and wheat flour in the ratio of 0:100,5:95, 10:90 and 15:85 respectively.Methods:Physico-chemical, antioxidant activity, total phenolic content and physical properties of amaranth supplemented bread were evaluated.Results:Results revealed an increase in moisture content from31.41 -33.35%, ash content 0.95- 1.52%, protein content 12.19% -13.23%, fat content 2.21% -2.81% and crude fiber 1.13-1.74%, and decrease in nitrogen free extract, alkali water retention capacity 52.11-47.35% and 137.66-112.00% respectively. Also it was observed that amaranth flour supplemented bread showed decrease in total phenolic content, antioxidant activity and FRAP assay with increase in substitution level. Color evaluation showed increase in L* and a* value of bread crust, while as bread crumb shows decrease in b* and L* value respectively. Nutritional evaluation revealed that among the samples tested 85% wheat flour and 15% amaranth flour supplemented bread was rated best as it was also evident from nutritional analysis.Conclusion:Maximum substitution of wheat flour with amaranth flour were 10% in terms of desirable bread quality attributes. The composite breads would serve as functional food, because of its high nutritional value than whole-wheat bread.

Chemical, Functional and Sensory Properties of Extruded Breakfast Strips Produced from a Blend of Orange-fleshed Sweet Potato, Soybean and Plantain Flour

Breakfast strips were produced from different blends of orange-fleshed sweet potato (Ipomea batatas), plantain (Musa paradisiaca) and soybean (Glycine max) flours with substitution ratios of 100:0:0, 90:10:0, 90:0:10, 80:10:10, 70:15:15, 60:20:20 and 50:25:25 and labelled as samples A, B, C, D, E, F and G, respectively. The blends were evaluated for functional properties, total carotene, vitamins (B2 and B6) and sensory properties of the breakfast strips with a commercial breakfast food (Flakes) as control (sample H) . For the functional properties, the water absorption capacity decreased while the oil absorption increased with an increase in substitution levels of the soybean flour. The bulk density, solubility, swelling power and swelling volume were higher in sample A. The least gelation capacity maintained a constant rate of 4% across the blends. The moisture content of the strips ranged from 7.25-9.40%. The Ash contents were below 3% for all the blends. The protein contents increased with an increase in substitution with soybean flour while sample A - breakfast strips from 100% orange-fleshed sweet potato flour showed the highest value for fats (5.62%). The fibre content ranged from 0.69 to 5.14% and carbohydrate content reduced with an increased substitution with soybean flour (72.25-78.70%). The energy value ranged from 351.90-384.80 Kcal/100 g which was within the limit recommended for breakfast foods. Total carotene content increased with increased substitution with orange-fleshed sweet potato (15.18-33.56 mg/kg) which is significantly higher than the control at 0.75 mg/kg. The result of the sensory evaluation showed that the overall acceptability of the samples produced compared favourably with the control. Sample A and B showed a vitamin B2 of 4.70 and 4.00 mg/kg, respectively. However, the values decreased with increase in the addition of soybean while vitamin B6 increased with increase in soybean.

Functional and antioxidant properties of cookies incorporated with foxtail millet and ginger powder.

The functional, sensory, nutritive, phytochemical and antioxidant properties of flours derived from wheat, foxtail millet and ginger along with the cookies formulated from these ingredients was studied. The foxtail millet (20, 30 and 40%) and ginger powder (5, 10 and 15%) blended wheat flours were investigated and compared to control (100% wheat flour). The increase in substitution levels of both the alternatives improved the functional properties of the composite flour and cookies formulated. Sensory analysis revealed that cookies prepared from 30% foxtail millet and 10% ginger powder had comparable scores. These were further subjected to nutritive and phytochemical analyses. The results revealed that cookies formulated using both the alternatives had reasonable proximate composition comparable to control. The substituted cookies had higher total soluble phenolic content and antioxidant capacities in terms of DPPH and ABTS scavenging potential and a strongly positive correlation was observed between the total soluble phenolic content and antioxidant capacities in composite flour and the cookies formulated from the flours. Overall the addition of foxtail millet flour (30%) and ginger powder (10%) improved the nutritional and phenolic linked antioxidant potential which can lead to shelf life extension and enhanced health benefits.

Role of barium substitution on oxygen vacancy reduction in BiFeO3 thin films

Despite high antiferromagnetic Neel and ferroelectric Curie temperature bismuth iron oxide (BiFeO3) is inherited with some drawbacks. These drawbacks include its weak ferromagnetic behavior and large leakage current. For overcoming these drawbacks we here report sol–gel preparation of barium substituted BiFeO3 (Bi1-xBaxFeO3; x = 0.0–0.3) thin films. Formation of rhombohedrally distorted structure is observed in XRD patterns. Replacement of Ba2+ in host lattice leads to strain relaxation in films. This will create oxygen vacancies that are less in number and less mobile and suppressed. Decrease in oxygen vacancies with increase in substitution level is also confirmed using XPS and EDS analysis. Barium atoms are fully dissolved in the lattice at low substituent concentration (x = 0.05–0.2). At high concentration (x = 0.25 and 0.3) peaks corresponding to BaO phase are observed in XRD patterns. SEM images show grain size < 60 nm. Increase in dielectric constant takes place from 45.8 to 153.61 (log f = 4.0) with increased barium concentration from 0.0 to 0.2. Cole–Cole plots indicate the dominant role of grain boundaries in dielectric process. Detailed room temperature impedance and Arrhenius plots reveal that oxygen vacancies are less mobile and suppressed. This results in enhanced insulting nature of thin films. This is also supported by high activation energy of 1.8 eV. Enhanced dielectric constant and decreased conductivity is also supported by increase in work function from 5.08 to 5.12 eV. Bi1–xBaxFeO3 thin films show ferromagnetic behavior. High saturation magnetization of 139.35 emu/cm3 is obtained for barium concentration x = 0.2. Decrease in magnetocrystalline anisotropy and size of single domain also adds to enhancement of magnetization.

Amaranth Leaves and Skimmed Milk Powders Improve the Nutritional, Functional, Physico-Chemical and Sensory Properties of Orange Fleshed Sweet Potato Flour.

Vitamin A deficiency (VAD) and under nutrition are major public health concerns in developing countries. Diets with high vitamin A and animal protein can help reduce the problem of VAD and under nutrition respectively. In this study, composite flours were developed from orange fleshed sweet potato (OFSP), amaranth leaves and skimmed milk powders; 78:2:20, 72.5:2.5:25, 65:5:30 and 55:10:35. The physico-chemical characteristics of the composite flours were determined using standard methods while sensory acceptability of porridges was rated on a nine-point hedonic scale using a trained panel. Results indicated a significant (p < 0.05) increase in protein (12.1 to 19.9%), iron (4.8 to 97.4 mg/100 g) and calcium (45.5 to 670.2 mg/100 g) contents of the OFSP-based composite flours. The vitamin A content of composite flours contributed from 32% to 442% of the recommended dietary allowance of children aged 6–59 months. The composite flours showed a significant (p < 0.05) decrease in solubility, swelling power and scores of porridge attributes with increase in substitution levels of skimmed milk and amaranth leaf powder. The study findings indicate that the OFSP-based composite flours have the potential to make a significant contribution to the improvement in the nutrition status of children aged 6–59 months in developing countries.

Hydroxypropyl and nanocrystal derivatives of white (Colocasia antiquorium) and red (Colocasia esculenta) cocoyam starches: functional, pasting, thermal and structural properties

Hydroxypropyl starch derivatives were prepared from the reaction of propylene oxide with the native starches of white and red cocoyam under alkaline conditions while starch nanocrystal derivatives were produced via acid hydrolysis method. The native starches and their hydroxypropyl derivatives were analyzed for functional behaviours, pasting properties, thermal properties, X-ray diffractometry and morphology while the starch nanocrystals were analyzed for solubility, X-ray diffractometry and morphology. Molar substitution values of the hydroxypropyl starch derivatives ranged between 0.23 and 0.26 and their degree of substitution ranged between 0.02 and 0.03. After derivation, the swelling power and water solubility of the native starches increased from 12.74 ± 0.02 to 21.36 ± 0.04 g/g (white cocoyam starch, WCS), 12.17 ± 0.04 to 18.06 ± 0.04 g/g (red cocoyam starch, RCS) and 11.61 ± 0.03 to 21.20 ± 0.06% (WCS), 12.21 ± 0.02 to 25.36 ± 0.05% (RCS) respectively. Except breakdown, all the pasting parameters (peak viscosity, hot paste viscosity, cold paste viscosity, setback, peak time and pasting temperature) significantly decreased (p < 0.05) as the levels of substitution increased. The gelatinization temperatures and peak height index reduced with an increase in substitution levels. Both native and hydroxyproylated starches exhibited CB-type X-ray patterns while the nanocrystals had V-type patterns. The starch nanocrystals formed precipitates with chloroform, but were practically insoluble in other solvents. The morphology of their microstructures revealed that the native starches were spherical and polygonal in shape while the nanocrystal starches appeared as aggregates. The starches studied could serve as alternative sources in meeting the ever-increasing demands of starch for food and non-food applications.

Utilization of Quinoa Seeds to Produce Gluten-Free Pan Bread

The effect of replacing rice flour with quinoa seeds (Chenopodium quinoa) flour on the proximate chemical composition, physical properties and sensory evaluation of free gluten pan bread were investigated. Baking trials were conducted at different levels of substitution (25, 50, 75 and 100% quinoa seeds flour). Results indicated that moisture, crude protein, lipids, ash and dietary fiber content were increased in substituted levels of quinoa seeds . While, total carbohydrates decreased by increasing in quinoa levels. Also, gluten-free pan bread samples prepared from rice flour(RF) and 25% quinoa flour (QF) proved to be of lower content in macro mineral (K, Ca, Mg, Na & P) and micro mineral (Fe, Mn & Zn) content ,while(G.F.P) bread samples prepared from 100% quinoa flour(qf) recorded high contents of all mineral under investigation. Weight (g) gradually increased infree gluten (G.F.P) bread samples parallel to the increase in substitution levels by quinoa flour(QF). On the other hand, volume and specific volume (cm3/g) of free gluten pan bread gradually decreasing by increasing levels of quinoa flour(QF). Organoleptic properties indicated that there were no significant differences(P <0.05) between control gluten-free pan bread sample (RF) and test sample containing QF at 25% level in most sensory characteristics with the exception of the color of crust and crumb in this sample which was significantly reduced (P<0.05) when compared with control bread(RF). Also, there were non-significant differences in bread samples containing 50% quinoa flour(RF) with other samples, softnes,crumb structure and over all acceptability . On the other hand, the gluten-free pan bread samples containing 75 and 100% QF were significantly differences (P<0.05) in all sensory properties and had less judging scores as compared to the control pan bread(RF) and the other pan bread sample containing 25% and 50%QF, except gluten free pan bread samples containing 50% showed non significant difference with samplas containing in crumb color and taste properties.

Quality evaluation of plantain-African Yam Bean flour blends and sensory properties of its cooked (amala) paste

Enrichment of plantain which is largely minerals and fibre rich food with moderate amount of protein and oils will provide a cooked (amala) paste with adequate nutrients dense meal. Quality evaluation of plantain-African Yam Beans (AYB) flour blends and sensory properties of its amala paste was evaluated for staple food production. Plantain was processed into flour and blends with AYB flour in ratio of 100:0, 85:15, 80:20, and 75:25 to give four samples. The proximate composition, functional and pasting properties, minerals profile, and sensory properties of the composite flour and its amala was determined using standard methods. The result of proximate composition showed that values for moisture content, protein, fat, fibre, ash, and carbohydrate ranged from 9.57 to 9.93, 14.43 to 18.24, 2.82 to 3.56, 6.78 to 7.8, 4.01 to 4.75, and 58.23 to 62.35%, respectively. Result of functional properties revealed that as AYB flour substitution level increases, the functional properties of the composite flour improved, while minerals profile result showed that only calcium and iron values of the elements determined marginally increased as substitution level of AYB increases compared to control sample. The study revealed that improvement in the nutritional quality and functional properties could be achieved with fortification of plantain amala with AYB flour addition. Based on the study sensory attributes result, it can be concluded that acceptable plantain-AYB composite flour and its amala can be produced from the blends of plantain-AYB flour at 20% inclusion level.

Structure and Electrocatalytic Reactivity of Cobalt Phosphosulfide Nanomaterials

Structure and electrocatalytic reactivity of cobalt mono-phosphosulfide nanoparticles supported on carbon nanotubes are investigated. Employing two different synthetic methods, we successfully synthesize cobalt mono-phosphosulfide nanoparticles adopting either the CoP crystal structure (CoP|S with the S/P ratio < 93%) or the CoS crystal structure (CoS|P with the P/S ratio < 73%). S substitution in the CoP structure makes the surface P atoms more oxidized whereas the S atoms stay completely reduced. P substitution in the CoS structure makes the surface S atoms more reduced but the Co atoms more oxidized whereas the P atoms stay completely oxidized. All the cobalt phosphosulfide nanoparticles exhibit relatively P-rich surface. The electrocatalytic performance of the nanoparticles for the hydrogen evolution reaction is studied. In acidic electrolyte, CoP|S nanoparticles show negligible dependence of activity on composition, whereas CoS|P nanoparticles are not stable enough to give any steady activity. In alkaline electrolyte, the activity of CoP|S nanoparticles decreases as the S substitution level increases, whereas that of CoS|P nanoparticles is weakly composition dependent.

Microwave properties of the Ga-substituted BaFe12O19 hexaferrites

The crystal structure features and the unit cell parameters were refined using the powder x-ray method for the solid solutions BaFe12−xGaxO19 (x = 0.1–1.2) barium hexagonal ferrites of M-type at 300 K. With increase of substitution level the unit cell parameters monotonically decrease. The temperature and field dependences of the specific magnetization were investigated by the vibration magnetometry method. The concentration dependence of the TC Curie temperature as well as the MS spontaneous specific magnetization and the HC coercive force at 300 K is constructed. With increase of substitution level the magnetic parameters monotonically decrease. The microwave properties of the considered solid solutions in the external magnetic bias field are also investigated at 300 K. With increase of Ga3+ concentration from x = 0.1 to x = 0.6 the frequency value of the natural ferromagnetic resonance (NFR) decreases in the beginning, and at further increase in concentration up to x = 1.2 it increases again. With increase in Ga3+ concentration the line width of the NFR increases that indicates the increase of frequency range where there is an intensive absorption of electromagnetic radiation (EMR). At the same time the peak amplitude of the resonant curve changes slightly. The frequency shift of the NFR in the external magnetic bias field takes place more intensively for the samples with small Ga3+ concentration. It is shown the prospects of use of the Ga-substituted barium hexagonal ferrite as the material effectively absorbing the high-frequency EMR.