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There may be a link between pre-harvest treatment and the post-harvest quality traits of tomato (Solanum lycopersicum L) fruit. The experiment was undertaken to determine the relationship between y...

In the study, the effects of in ovo injection of amino acids (L-methionine, L-lysine, and Larginine) and their combinations on hatching traits, post-hatch performance, cell-mediated immune response and blood profile of FUNAAB Alpha broiler chicken were evaluated. The study was carried out in two trials. In the first trial, a total of 360 hatching eggs of indigenous chicken were fumigated, weighed and placed in the incubator. On day 14 of incubation, candling was done and eggs with living embryos were distributed into four treatments; Control (un-injected eggs), L-methionine injected eggs, L-arginine injected eggs and Llysineinjected eggs. Each egg was injected 0.5 mL solution of the amino acid on day 18. Hatched chicks were distributed into three replicates containing 30 chicks each. In trial 2, another 360 hatching eggs were used in the treatments which were; Control (eggs without amino acid injection), L-arginine injected eggs, combination of L-arginine and Lmethionine injected eggs and combination of L-arginine and L-lysine injected eggs. On day 21 post-hatch, cell-mediated immune response, haematological and serum biochemical parameters were determined. Data obtained from the two trials were subjected to Completely Randomized Design. Results revealed the highest hatchability of 70.27% in the control treatment (un-injected), followed by 51.35% in arginine-injected eggs with the lowest (2.70%) in methionine-injected eggs. Arginine was found to enhance hatchability while L-methionine injected in ovo decreased hatchability. In the second trial, the results showed highest hatchability (89.58%) in eggs under the control, followed by 39.29%, 30.80% and 21.43% in eggs injected with the combination of arginine and lysine, arginine injected eggs, and those with arginine and methionine combination, respectively. Significant (p

There is consumer's preference for tender meat. The use of tenderizers to soften meat helps to reduce nutrient losses due to prolonged cooking. This study was conducted to compare the effects of four unconventional marinades (Pawpaw leaves extract, Lime-juice, and Carbonated drinks and distilled water) on the quality of beef. One thousand five hundred grams (1500 g) of beef excised from the thigh muscle was cut into twelve whole pieces of similar sizes and were randomly distributed into four experimental groups in a Complete Randomized Design (CRD). Treatment groups were randomly allotted to experimental marinades measuring 300mL with each marinade containing 100mL of tenderizers. Marination spanned for a period of 24 hours at a temperature of 4 °C. Data collected were: beef proximate composition, weights with pH of beef and marinades, cook and refrigeration losses and sensory scores. Results showed significantly (P0.05) crude protein, ash, moisture content, and calcium. Weights and pH from beef and marinades varied significantly (P

This study evaluated some quality attributes of pancakes from peeled and unpeeled sweetpotato flours and cassava starch. Cassava starch was substituted up to 30% of the total composite flour. The proximate composition, colour, carotenoid and functional properties of the different flour blends were determined. The flour blends were processed into pancakes and the proximate composition and sensory acceptability of the pancakes were determined. Data obtained were subjected to analysis of variance. The result showed that they were significant differences (p

Appropriate density of Golden melon (Cucumis melo L.) in the field is arrived at by correct spacing between, and within rows, a factor that can impact on weed incidence and crop yield. A field expe...

Adsorption isotherms of water yam flour were determined by static gravimetric method of saturated salt solutions in the range of water activities between 0.11 and 0.96 and at temperatures of 25, 35 and 45 °C. The experimental sorption data was fitted to five models: Guggenheim-Anderson-De Boer (GAB), Peleg, Iglesias-Chirife, Exponential and Oswin and the differential enthalpy and entropies were determined. Equilibrium moisture contents decreased with increase in temperature at all the water activities studied. Peleg model gave the best fit for the sorption isotherm of water yam flour. Monolayer moisture content values estimated from the GAB-model were found to decrease with increases in temperature. The differential enthalpy and entropy decreased with increases in moisture content. The isokinetic temperature was 371.32 K and the compensation theory was satisfied.

Biomass gasification mainly involves a process whereby agricultural residues or biomass are subjected to partial combustion for the biomass to undergo pyrolysis and reduction, thereby releasing its gaseous component such as hydrogen, carbon-dioxide and methane. Past studies have laid emphasis on the need to study the effect of moisture content and biomass types on the rate of gasification and gasifier efficiency. This study focused on the development of a downdraft gasifier for production of syngas using agricultural wastes as raw materials. The design of the Imbert type downdraft gasifier was based on specific gasification rate, called hearth load Gh, nozzle air blast velocities, throat inclination angle, air inlet diameter and size of reduction zone. The developed gasifier consisted of a reactor, cyclone and filtration unit of 0.006, 0.016, and 0.006 m3 capacities respectively. The testing and evaluation of the designed gasifier showed adequate capacity for biomass treatment by pyrolysis. The fabricated gasifier also showed high efficiency in the pyrolysis of the selected biomasses and the product yields are appreciable. The development and use of such gasifier especially for the treatment of other agricultural wastes is hereby solicited.

This research studied the effect of biomass types and moisture content on the performance of a downdraft gasifier. Sawdust, woodchip and bean chaff were used as test samples at three moisture contents (10, 20 and 30% w.b) which was determined with oven drying method and Pascal’s manometric tube was prepared to measure the quantity of methane, hydrogen sulfide, carbon dioxide and carbon monoxide in the syngas. The gas obtained at 10% moisture content for the three biomass after gasification was analyzed and compared to standard values. Ash content, gasification time and temperature were measured using standard methods. The ash contents at 10, 20 and 30% moisture contents for wood chips, sawdust and bean chaff were 0.210, 0.457, 0.750kg, 0.202, 0.290, 0.651kg and 0.295, 0.228, 0.394kg respectively. The gas samples were taken at 10% moisture for analysis because it produced the lowest ash content. Gas produced at 10% moisture content showed that methane, CO2 and H2S contents for wood chips; sawdust and bean chaff were 60.85, 27.50, 0.44%; 62.33, 23.77, 0.87% and 63.94, 18.91, 0.58% respectively. The values of CO was insignificant. The moisture content of the biomass significantly (p < 0.05) affected the values of ash content, gasification time and temperature but the effects of biomass types were not significant. Ash content and gasification time increased with increase in moisture level with the least value of 0.210 kg and 61 minutes at 10% moisture content respectively. The gasification temperature decreased as moisture level increased and vice versa. Increase in moisture level increased the ash content and gasification time. The higher the gasification temperature, the lower the time. Gasifier efficiency was also affected by moisture content and biomass types. The best gasifier efficiency was observed at 10% moisture content with 60, 57 and 75% for sawdust, woodchips and bean chaff respectively.

Kinetics of mass transfer [moisture content, oil uptake, total carotenoid (TC) and shrinkage] during frying of yellow fleshed cassava roots (TMS 01/1371) was investigated. Slices were divided into (i) fresh and (ii) pre-dried to 75 % moisture content before atmospheric frying and (iii) vacuum fried. Percentage TC and activation energies of vacuum, fresh and pre-dried fried samples were 76, 63 and 61 %; and 82, 469.7, 213.7 kJ/mol, respectively.

Effects of frying treatments on texture (hardness) and colour parameters (L,a,b,ΔE) during deep fat frying of yellow fleshed cassava root slices (TMS 01/1371) were investigated. Slices (dimension of 40 mm × 25 mm × 3 mm) were divided into three portions and subjected to vacuum frying (fresh slices) and atmospheric frying (fresh and predried slices) and equivalent thermal driving forces (ETDF) of 60°C, 70°C, and 80°C were maintained during frying. The quality attributes investigated were best preserved in vacuum fried chips. The overall colour change in chips fried under vacuum conditions at 118°C and 8 min was the least (21.20) compared to fresh and atmospherically predried ones (16.69 and 14.81, resp.). A sharp reduction in the breaking force was obtained for all frying treatments after 8 min and this effect was the least in vacuum fried chips. First-order kinetics modeled the changes in quality attributes for all the temperatures investigated. Rate constants k (min−1) obtained for vacuum frying were almost equal to that of atmospheric frying while activation energies for hardness and colour change were 53.30 and 467.11 KJ/mol, respectively. Quality attributes studied were best preserved during vacuum frying.

Protein dense, fiber-rich extruded snacks were produced from blend of bambara groundnut flour, cassava starch, and corn bran flour using a single screw cooking extruder. The snacks were analyzed for their physical properties and proximate composition using standard laboratory procedures. The expansion ratio, specific volume, breaking force, and breaking strength index (BSI) of the snacks ranged from 0.85 to 1.22, 0.75 to 1.30 g/cm3, 3.95 to 36.45 N, and 0.99 to 9.11 N/mm, respectively. The breaking force and BSI were high and increased at increasing levels of cassava starch and corn bran inclusion. Moisture, protein, fat, carbohydrates, crude fiber, and total dietary fiber contents of the snacks were 5.40–10.80, 3.26–17.62, 0.68–10.35%, 60.56–85.03, 0.32–4.78, and 7.36–28.74%, respectively. The study revealed a great potential of obtaining a nutrient dense extruded snack from underutilized plant commodity (bambara groundnut) and waste from corn milling (corn bran).

Mass transfer (moisture loss and oil uptake) kinetics during deep fat frying of wheat starch and gluten based snacks was investigated. Both followed a modified first order reaction. Activation energies, z-value, and highest values of D and k for moisture loss and oil uptake were 28.608 kJ/mol, 129.88 °C, 490 and 0.0080 s−1; and 60.398 kJ/mol, 61.79 °C, 1,354.71 and 0.0052 s−1, respectively.

Flour from Mucuna beans (Mucuna pruriens) were used in producing texturized meat analogue using a single screw extruder to monitor modifications on the proximate composition and the functional properties at high moisture level. Response surface methodology based on Box Behnken design at three levels of barrel temperature (110, 120, 130°C), screw speed (100,120,140rpm) and feed moisture (44, 47, 50%) were used in 17 runs. Regression models describing the effect of variables on the product responses were obtained. Descriptive profile analyses and consumer acceptability test were carried out on optimized flavoured extruded meat analogue. Responses were mostly affected by barrel temperature and moisture level and to a lesser extent by screw speed. Optimization results based on desirability concept indicated that a barrel temperature of 120.15°C, feed moisture of 47% and screw speed of 119.19 rpm would produce meat analogue of preferable proximate composition, functional and sensory properties which reveals consumers` likeness for the product.

This study investigated the mineral and antinutrient composition of extruded snack produced from different blends of high quality cassava and tigernut flour. The extruded snacks were produced using a single-screw laboratory extruder at constant feed moisture (27%), screw speed (60 rpm) and barrel temperature (80C). It was observed that the extrudates had higher values for mineral composition (phosphorus, calcium, magnesium, potassium and iron) than the composite flour which showed that extrusion cooking improves the absorption of the minerals. The antinutrient (tannin, phytate, saponin, oxalate, alkaloids and total phenolic) contents of all the flour blends significantly (P

The drying behavior of fever leaves was investigated in a convective hot air dryer with forced convection at a fixed air velocity of 1.5m/s and drying air temperatures of 35, 45, 55 and 650C. The constant rate period was absent and the drying curve took place in the falling rate period. Experimental data was fitted to six thin-layer drying models – Page, Modified page II, Henderson and Pabis, Modified Henderson and Pabis, Two term and Newton. The performances of the models were investigated by comparing the coefficient of determination (R2), reduced chi-square (÷2) and root mean square error (RMSE) between observed and predicted moisture ratios. The page model showed a good agreement with the data obtained while the effect of drying air temperature on the constants and coefficient of the page model was investigated. The effective diffusivity increases as temperature increases and range between 5.551 x 10-12 – 3.379 x 10-11m2/s while the activation energy was estimated to be 80.78kJ/mol. Keywords : Fever leaves, convective hot air drying, modeling, diffusivity, activation energy Nigerian Food Journal Vol. 25 (1) 2007: pp. 146-153