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- ItemOptimization of oil extraction from locust bean using response surface methodology(European Journal of Lipid Science and Technology, 2011) Rahman Akinoso and Akeem Olayemi RajiOptimization of oil extraction from locust beans (Parkia biglobosa) using central composite rotatable design of RSM was carried out. Independent variables were roasting temperature (90, 100, 110, 120, 1308C) and roasting duration (5, 10 15, 20, 25 min), while the responses were oil yield (OY), free fatty acid (FFA), color (CO), stability, anisidine value (AV), and specific gravity (SG). Data obtained from this study were analyzed using ANOVA and regression analysis. OY, FFA, CO, oil stability, AV, and SG of the oil ranged between (19.0–22.5%), (0.65–3.1%), (37.9–199.9 mg/L), (3.6–6.4%), (11.4– 59.9 mg/L), (0.7–0.9), respectively. Roasting conditions significantly influenced all dependent variables at p<0.05. Coefficients of determination (R2) of the generated models ranged from 0.49 to 0.98. Optimum roasting condition was 1088C for 10 min. This gave 22.3% OY, 1.7% FFA, 54.9 mg/L CO, 4.1% stability, 16.5 mg/L AV, and 0.9 SG. Desirability of 0.8 was obtained for optimum conditions
- ItemThermal properties of some selected nigerian soups(Agricultural Sciences, 2013) Raji Akeem Olayemi , Akinoso RahmanA preliminary investigation was carried out on the thermal properties of “Ewedu” (Corchorusolitorus), “Ila” (Hibiscus esculentus), “Ogbono” (Irvingia gabonensis) and ” Kuka” (Adansonia digitata) soups, because information on the thermal properties of these soups has not been established. The specific heat capacity, thermal conductivity and thermal diffusivity parameters were determined as a function of their proximate compositions by applying additivity principles. The proximate composition obtained for the soups were: ewedu (moisture content; 88.60 ± 0.14%, protein; 6.00 ± 0.01%, fat; 1.05 ± 0.05%, ash; 1.81 ± 0.01%, crude fiber; 1.47 ± 0.02%, carbohydrate; 1.05 ± 0.04% and energy 34.27 ± 1.89 k/cal/10 g), Ila (moisture content; 77.25 ± 0.35%, protein; 15.94 ± 0.08%, fat; 2.13 ± 0.04%, ash; 1.90 ± 0.14%, crude fiber; 1.15 ± 0.07%, carbohydrate; 1.48 ± 0.11% and energy 87.61 ± 3.31 k/cal/10 g), Ogbono (moisture content; 68.87 ± 0.14%, protein; 18.70 ± 0.42%, fat; 6.12 ± 0.11%, ash; 4.55 ± 021%, crude fiber; 1.04 ± 0.60%, carbohydrate; 1.90 ± 0.01% and energy; 133.08 ± 0.60 k/cal/10 g) and Kuka (moisture content; 78.54 ± 0.06%, protein; 8.80 ± 0.41%, fat; 2.29 ± 0.01%, ash; 2.09 ± 0.01%, crude fiber; 0.88 ± 0.02%, carbohydrate; 7.42 ± 0.08% and energy 85.64 ± 0.17 k/cal/10 g). The specific heat capacity, thermal conductivity and thermal diffusivity for the soups were; ewedu (3.851 kJ/ kg/K, 0.530 W/m/K and 1.358 x 10-7 m2/s), Ila (3.554 ± 0.01 kJ/kg/K, 0.483 W/m/K and 1.281 x 10-7 m2/s), ogbono (3.332 kJ/kg/K, 0.447 W/m/K and 1.220 x 10-7 m2/s) and kuka (3.586 kJ/kg/K, 0.494 W/m/K and 1.296 x 10-7 m2/s)respectively. The values obtained for the thermal properties showed that the soups can mildly retain or dissipate heat during canning and freezing.
- ItemA Comparative Study of Energy Demand of Instant- Pounded Yam Flour Production Methods(2014)Traditionally, method of producing pounded yam by pounding cooked yam using pestle and mortar is time and labour consuming, thus discouraging consumption of the food among urban elite. Conversion of yam tubers to instant-pounded yam flour requires quantifiable magnitudes. Therefore, the objective of this study was to determine energy conservation potentials of the established three instant-pounded yam flour methods of production. Data were collected from nine instant-pounded yam flour producing factory using structured questionnaires, oral interview, and direct measurement of processing parameters. The data were fit into standard equations to estimate energy demand. Energy required for processing 1000 kg of yam to instant-pounded yam flour using cooking method, steaming method and wet-milling methods were 6720.15MJ, 6934.48MJ and 4296.56MJ respectively, equivalent to 6.7 MJ/kg, 6.9 MJ/kg and 4.3 MJ/kg respectively. Energy intensity for peeling, washing, slicing and packaging were 0.0055 MJ, 0.003 MJ, 0.0076 MJ and 0.2 MJ respectively, and are the same for all the methods studied. Drying consumed more than half of the total energy requirements in each method; cooking (66.26%), steaming (79.04%) and wet-milling methods (76.57%). Using energy demand as criterion, wet- milling method is recommended
- ItemQuantitative analysis of some brands of chloroquine tablets marketed in Maiduguri using spectrophotometric and high performance liquid chromatographic methods(2014)The experiment involves analysis of chloroquine using ultra violet spectrophotometer in the ultraviolet range (200 400nm) and high performance liquid chromatography(HPLC) in which the samples were dissolved in various solvents and their various absorbance, peak area at various wavelength were determined and compared with that of the standard, wavelength of maximum absorbance at 331nm for chloroquine. Percentage and milligram content for each sample was determined so as to note if it was within the acceptable range of (92.5-107.5%) for chloroquine. For those that passed the test or if it was below or above the range for samples that are substandard or highly concentrated. The samples’ absorbance and peak area was used along side with the standard absorbance and peak area to calculate the percentage content of each sample. It was observed that of the six samples of chloroquine tablet, none passed the test using UV spectrophotometer while Dana chloroquine with 98.7%, Evans chloroquine 107.3% and Palquine 106.4% passed using HPLC.
- ItemEmbedded energy of on farm losses and energy analysis for maize production in Nigeria(2014)Food losses and wastages occur at different points in the food supply chains such as farm, processing, storage, transportation, food services and household. On farm losses are associated with the losses of embedded energy. Thus, embedded energy of on farm maize losses and general energy flow pattern was investigated. Primary and secondary data were used. Primary data was collected through multistage stratified random sampling of 40 maize growers while secondary data was obtained from yearly in-situ collection of agricultural data by agricultural agency in Nigeria. Therefore the analyzed and discussed input energy- output energy values were averages of data collected over the years. Total energy input and output were respectively quantified as 9502.17 and 33510.58 MJha-1. The input energy estimated was classified as industrial energy (84.38%), biological energy (15.62%), direct energy (31.14%) and indirect energy (68.86%). Energy efficiency, energy productivity, specific energy, net energy and agrochemical energy ratio were 3.53, 0.19 kgMJ-1, 5.28 MJkg-1, 24008.41MJha-1 and 60.1% respectively. The total embedded energy in the lost maize for the period of study was 6816.13MJ. The high loss of maize on Nigeria farm was an indicator for increased in embedded energy lost from 214.03-1995.53MJ. Year 2012 had the highest share of embedded energy loss (29.28%) followed by year 2011(28.46%), while lowest share of (3.14%) was estimated for the year 2000.
- ItemEffect of freeze–thaw cycles on the nutritional quality of some selected Nigerian soups(Food science & nutrition, 2015) Akeem Olayemi Raji, Rahman Akinoso & Monsurat Oyewale RajiFreezing and thawing are heat transfer processes, involving chemical changes which may greatly affect product quality. Due to sparse literature on freeze–thawed cycles and its effects on soups quality, the effect of freeze–thaw cycles on the nutritional quality of selected Nigerian soups has to be investigated. Soups (Ila, Ewedu, Ogbono, and Kuka) were prepared using standard recipes. The soups were packaged in plastic and aluminum containers, frozen at −20°C, and thawed with microwave oven, hot water (100°C), and at ambient condition for four cycles of 5-day interval. After each cycle, chemical compositions of the samples were determined using AOAC methods. Data were analyzed using ANOVA at P = 0.05. Moisture, protein, fat, crude fiber, ash, and carbohydrate contents of the freeze–thawed soups were 63.6–88.6%, 3.6–8.8%, 1.0–6.1%, 0.8–1.2%, 1.8–4.6%, and 0.9–15.6%, respectively. Mineral contents were iron (5.0–6.8 mg/100 g), calcium (68.1–190.8 mg/100 g), sodium (144.4–231.7 mg/100 g), potassium (200.4–302.1 mg/100 g), and phosphorus (228.0–337.2 mg/100 g). Vitamins were vitamin A (29.5–59.9 mg/100 g), vitamin B (10.1–36.4 mg/100 g), and vitamin E (28.4–90.2 mg/100 g). Microwave-thawed plastic soups had limited nutritional losses when compared with other thawing methods, and should not be extended beyond the third cycle because of increas ing reduction in fat and protein, indicating deterioration.
- ItemChemical, Microbial and Sensory Properties ofImproved Shea Butter during Ambient Storage(Asian Journal of Agriculture and Food Sciences, 2015) U. I. Ibanga, A. Raji, A. K. Oladele and C. IsinguzoManually extracted improved shea butters are vegetable fat from parboiled, fried, toasted and boiled shea kernel streated by clarification and deodorization with citric acid solution and coconut essence. They were packaged in transparent plastic containers and stored on the laboratory shelf at 28±2oC for four months. Sensory changes were monitored biweekly and peroxide and microbial changes were monitored weekly using standard methods. Unlike the traditionally processed shea butter which was not treated with citric acid and had an optimal sensory acceptability of two weeks, sensory attributes of improved shea butter samples improved during storage. There were neither noticeable microbial growths nor rancidity. Treatment with citric acid solution and coconut flavour thuspreserved the sensory attributes and keeping quality of improved shea butter at ambient storage.
- ItemIdentification of aromatic compounds and their sensory characteristics in cassava flakes and “garri” (Manihot esculenta Crantz)(CyTA - Journal of Food, 2015-08-10) Lasekan Ola; Hosnas Rihana; Ng Siew; Lin Mee; Azeez Shakirah; Teoh Li; Gholivand Somayeh; Shittu RafiatCassava flakes and “garri” are some of the popular cassava products consumed in Africa, Southeast Asia, and Brazil. These products are cherished for their creamy colour and characteristic aroma. The aroma compounds responsible for the unique aroma notes of these products were evaluated by means of solid-phase micro-extraction (SPME). Results confirmed that the divinylbenze-carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fibre was the most appropriate for the isolation of aroma compounds in the cassava products. In addition, the best response was attained when the extraction temperature was 60°C, equilibrium time 20 min, extraction time 10.94 min, and water addition 35%. Analysis of the odorants led to the identification of 21 compounds with an array of odour notes. However, results of the aroma extract dilution analysis (AEDA), and odour activity values (OAVs) showed that guaiacol, 3-methylbutanal, methylpropanal, and butyric acids contributed intensely to the characteristic aroma of both cassava flakes and garri
- ItemInfluence of Sprouted African Breadfruit milk extract on Nutritional, Sensory and Microbiological Quality of Kunun-zaki(2016)Kunun -zaki is a popular traditional non alcoholic drink value for its high refreshing quality, sweet -sour taste and high viscosity value. The major unit operations in processing include washing, steeping, wet milling, sieving, mixing, cooking, cooling and fermentation. This study evaluated the nutritional, sensory and microbiological quality of kunu-zaki using Sorghum bicolor (sorghum) substituted with milk extract of sprouted Africa bread fruit (ABF) seed at 0-25% levels. The results obtained from substitution at 25% level increased the protein and ash content while carbohydrate and moisture content were reduced significantly (p< 0.05%). pH, titratable acidity and total solid ranged were 4.12-4.37; 2.18-2.26 (g/ml) and 14.98-17.98 (%) respectively in all the substituted ABF kunun-zaki. Total viable counts of microbial load were in the range of (1.65-2.41, 1.68-2.66 and 33.4-42.5) x103 cfu/ml for kunun- zaki stored for 1, 10 and 15 days at 7 oC respectively. Control sample had lowest viable count throughout the storage periods than the ABF substituted samples. There was a significant difference (p < 0.05) in the sensory attributes with regards to taste and flavor of control at 25% substitution level. General acceptability of the scores of the products increased from 6.87 to 7.40 with the increased in the level of ABF substituted in kunun-zaki production.
- ItemPotentials of Trifoliate Yam (Dioscorea dumetorum) in Noodles Production(2016)Trifoliate yam (Dioscorea dumetorum) is a high yielding but under exploited yam species. Potential of its flour in noodle production was investigated in this study. Trifoliate yam flour was produced and substituted for wheat flour at 20 -70% levels. Noodles were produced from the composite flour and evaluated for their proximate composition, functional properties, colour and cooking properties, using standard methods. Sensory attributes of the noodle were also determined using panelists. Data were analyzed using ANOVA at (p<0.05). The results showed that incorporation of trifoliate yam flour into wheat flour increased the moisture, crude fibre, ash and fat content of dried noodles. The moisture content ranges from 7.16 - 12.93%, crude fiber (0.72 - 1.30%), Ash (1.20 - 2.88%), fat (18.26 - 28.54%), protein (5.88 - 7.79%) and carbohydrate (51.18 - 62.77%). The water and oil absorption capacities of the noodles increased from 1.60 g to 2.03 g and 0.72 g to 1.21 g respectively, with increase in levels of trifoliate yam flour. Significant differences (p<0.05) exist between the colour of raw sheet noodles and the cooked noodles. The optimum cooking time and cooking loss were in the ranges (5.43 min to 7.06 min) and (9.31 - 15.09%) respectively. Sensory evaluation showed that the acceptability of uncooked and cooked dried noodles were at the moderate level. The substitution of different levels of trifoliate yam flour did not give significant (p<0.05) influence on sensory attributes except for the taste and color of dried noodles. Trifoliate yam has a good utilization potential in noodle production and could be used as substitute to wheat in human nutrition and in the food industries since they compare favorably in their nutritional compositions.
- ItemStorability of “DodoIkire” (over -ripe plantain-basedsnack) at ambient temperature (28±2ºC)(2016)“DodoIkire”is an example of traditional snack commonly consumed in western part of Nigeria. Effects of storage packaging modes and durations on its microbiological quality and sensory attributes at room temperature were investigated. Samples were collected from commercial sellers inIkire,Apomu and Ikoyi Towns. They were packaged and stored at room temperature (28±2ºC) in three different materials namely; Open storage in disposable cup (OS), low density nylon(LD) and high density polyethylene(HD) for a month.A sample of DodoIkire was prepared in the Food processing Laboratory of Wesley university of Technology, Ondo, to serve as Control. Total viable counts and fungi counts were conducted at intervals of two weeks using pour plate method. Sensory evaluations were carried out at these intervals using semi-trained panelist on a nine point hedonic scale. The results showed that the „DodoIkire‟ offered for sale has low level of initial microbial loads. The choice of packaging system and duration of storage significantly influenced (p<0.05) the level of infestation within one month of storage in different materials, with OS permitting the highest, followed by LD and then HD. Similarly, these two parameters also significantly influenced (p<0.05) the rate at which sensory attributes were lost in the same order.High density polyethylene (HD) offered best protection and is hereby recommended for the storage of DodoIkire. However, consumption of DodoIkire after a month of storage should be discouraged
- ItemCOMPARATIVE EVALUATION OF DAIRY WITH VEGETABLE BASED (SESAME, GROUNDNUT AND SOYBEAN) YOGHURTS(2016)Sesame, soybean and groundnut are important oil and protein rich seed. One important processing method to enhance their consumption is the production of vegetable based yoghurt. Fresh samples of sesame, soybean and groundnut were processed into their individual milk extract and inoculated to form respective vegetable yoghurt with addition of sweetener. The yoghurt samples were analyzed and compared with reconstituted full cream milk powder (FCMP) based yoghurt for their chemical composition, microbiological and sensory qualities using standard methods. The protein content of FCMP was 3.48% and vegetable based yoghurt ranged between 3.18 to 3.36% and there was no significant difference (p˂ 0.05) among them. The Carbohydrate content of FCMP was the lowest (3.19%), the value obtained for the vegetable yoghurt ranged between 4.99 and 6.44%. The fat content of FCMP (2.5%) was not significantly different (p˂ 0.05) from groundnut (2.38%) and sesame (2.4%) based yoghurt. The pH of the yoghurt varied between 4.08 in soybean to 4.34% in groundnut. The sensory evaluation also showed that there was no significant difference (p˂ 0.05) among the vegetable yoghurts in aroma, viscosity, taste and overall acceptability. Microbiological examination revealed that the yoghurt samples were within minimum acceptable standards
- ItemPlantain-starch: Microstructural, physicochemical, and morphological characteristics of two cultivars grown in Malaysia(WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, 2016-02-11) Shittu Rafiat; Lasekan Ola; Karim Roselina; Sulaiman RabiahStarches isolated from mature green “Nangka” and “Tanduk” plantain (Musa paradisiaca L) cultivars grown in Malaysia were appraised for their morphological, physicochemical, and structural properties. The amylose contents of “Nangka” and “Tanduk” starches were 31.79 and 26.08% and the degree of relative crystallinity were 62.1 and 52.1%, respectively. Both cultivar starches presented an A-type diffraction pattern, which has rarely been reported for banana starches. Gelatinization temperatures evaluated by differential scanning calorimeter were higher for “Tanduk” starch than “Nangka” starch. The scanning electron micrograph of “Nangka” starch granules was larger than “Tanduk” starch with an average particle size of 38.77 and 23.91 μm, respectively. In addition, “Nangka” starch produced lower molar mass (Mw) and gyration radius (RG) compared to “Tanduk” starch.
- ItemComparative evaluation of anti-oxidative potentials of fermented locust bean condiment and its moringa fortified variant(African Journal of Biotechnology, 2017) Gibson L. Arueya, Maimuna Sani and Akeem Olayemi RajiThe need to boost daily intake of natural antioxidants to combat free radicals causing degenerative diseases has become more imperative. Fermented locust bean condiment was fortified with moringa leaf powder (rich in antioxidants) at 20, 30 and 50% substitution levels. Proximate composition, phenolic content, total flavonoid, reducing power, and the sensory properties of the condiments were determined using standard methods. Data obtained were analyzed using analysis of variance (ANOVA) at p≤0.05 and compared with catechin as standard. Possible correlations between trends in the proximate components and antioxidative properties were examined. Proximate components of the fortified condiments: Moisture (6.92 to 7.17%), crude protein (39.23 to 42.91%), crude fibre (5.21 to 5.63%), total ash (4.24 to 6.27%), and carbohydrate (12.21 to 16.31%) compared favorably in most parameters with those of the unfortified. The phenolic content, total flavonoid, and reducing power of the fortified condiments (with rising substitution level (p≤0.05)) increased significantly ranging from 13.5 to 20.20, 5.35 to 18.3, and 10.6 to 22.1 µg/g, respectively at concentration of 1000 µg/g. Apparently, crude fibre and ash contents correlated positively with reducing power potential across several concentration gradients. Mean sensory scores [taste (5.00 to 5.29) and mouth feel (4.86 to 5.43)] for the fortified variant was not significantly different from those of the control. Condiment fortified with 20% moringa leaf exhibited the highest antioxidant capacity among the samples and may be a sustainable means of meeting the recommended daily requirement of antioxidants among the populace.
- ItemFREEZING AND THAWING CHARACTERISTICS OF SOME SELECTED NIGERIAN SOUPS(Journal of Food Process Engineering, 2017) AKEEM OLAYEMI RAJI1, RAHMAN AKINOSO, UCHE IBANGA and MONSURAT OYEWALE RAJIFreezing and thawing characteristics of some Nigerian soups (Ila, Ewedu, Ogbono and Kuka) were investigated. The soups were prepared using standard recipe and packaged in plastic and aluminum containers, frozen at 220C and thawed with microwave oven water (2.45 GHz), hot water (100C) and at ambient condition (30 6 2C). Freezing and thawing durations, rates, losses and points of the soups were determined using standard methods. Data were analysed using SPSS at P 5 0.05. Freezing duration, rate, loss and points were 70.0–145.0 min, 0.4–0.7C/min, 1.75–3.79%, and 21.8 to 22.4C respectively. Thawing duration, rate, loss and points were, 1.8–53.0 min, 0.4–10.9C/min, 0.1–2.4% and 21.7 to 22.3 C respectively. Soups packaged in aluminium containers frozen faster than in plastic containers. Microwave-thawed soups in plastics showed the best thawing characteristics which include high thawing rate, short thawing time and low thawing loss.
- ItemEffect of Cooking Time on the Physical, Chemical and Thermal Properties of Acha Seeds(International Journal of Food Studies, 2017) Akeem Olayemi Raji and Hajarat O. Nassam and Tawakalitu Eniola Aruna and Monsurat Oyewale Raji and Maimuna SaniAcha is a less utilized cereal grain in Africa. Scaling up of the processing technology of acha seeds is desirable if accurate information on effect of processing on its properties is available. This study investigated the effect of cooking duration on the chemical and physical properties of acha seeds. Cooking times (2.5, 5, 7.5 and 10 minutes) at 100°C were used. The volume, length, breadth, thickness, porosity, density, sphericity, aspect ratio, specific heat capacity, thermal conductivity, thermal diffusivity, mois ture, protein, fat, ash, crude fibre and carbohydrate were determined using standard methods. Data were analysed using ANOVA at p = 0.05. The results obtained revealed that varietal difference had a significant effect on volume, length, breadth, thickness, true density, bulk density, porosity, spheric ity and aspect ratio. The moisture content, ash, protein, crude fibre, fat, carbohydrate, specific heat capacity, thermal conductivity and thermal diffusivity varied from 8.80 - 56.17 %, 0.32 - 1.87%, 1.92 -11.50%, 0.29 - 1.58%, 0.32 - 2.81%, 40.94 - 76.26%, 1.66 -2.97 kJkg−1K−1, 0.26 -0.43 Wm−1K−1and0.85 x 10−7- 1.17 x 10−7 ms−2respectively, as significantly influenced by cooking time. Cooking for 7.5 minutes was appropriate using the moisture uptakes and thermal properties as criteria.
- ItemProtein enrichment of yam peels by fermentation with Saccharomyces cerevisiae (BY4743)(Annals of Agricultural Science, 2017) Tawakalitu E. Aruna , Ogugua C. Aworh , Akeem O. Raji , Aderonke I. OlagunjuConventional sources of protein are becoming inadequate for protein-based food supply. Non conventional sources are of much concern, but literature is sparse on the protein quality of yam peel biomass. Solid state fermentation (with and without ammonium sulphate) of yam peels was carried out for 96 h, using Saccharomyces cerevisiae (BY4743). Samples from fermented biomass were collected at 24 h interval for 96 h, oven dried at 60 C, cooled, milled and assayed for chemical and amino acid composition. The crude protein, true protein, fat and ash contents increased significantly from 6.60%, 4.38%, 1.12% and 4.45% to 15.54%, 13.37%, 2.09% and 8.02% respectively when fermentation reached 96 h in the pres ence of ammonium sulphate. High protein content with good amino acids profile (leucine, valine, lysine and threonine as essential amino acids) was recorded in ammonium sulphate supplemented peels fer mented for 96 h. Remarkable increase in protein and amino acids suggested that ammonium sulphate supplement influenced the biomass protein yield and quality.
- ItemReconstitution potentials and moisture sorption isotherms of selected freeze dried Nigerian soups(Journal of Food Process Engineering, 2017) Akeem Olayemi Raji, Rahman Akinoso, Tawakalitu Eniola Aruna, Monsurat Oyewale RajiSelected Nigerian soups were freeze dried with the aim of establishing their storage stabilities and reconstitution potentials. Freshly prepared soups were freeze-dried under vacuum for 12–14 hr. Sorption isotherms were determined at 278C using gravimetric method at water activities (aw) of 0.12 0.8. Reconstitution potentials were determined at 30 and 1008C using gravimetric methods. Data were analyzed using SPSS for the best fit model equations (Peleg, GAB, Oswin, and Langmuir). The rehydration ratios of the freeze dried soups ranged from 1.00 to 9.11 g absorbed water/g dry matter. Soups were optimally reconstituted at 308C for 30 min and at 100 8C for 5 min. The equilibrium moisture contents of freeze dried soups ranged from 8.84 to 27.50%. The GAB model was the best estimator for predicting the monolayer moisture contents of the soups, which ranged from 7.87 to 9.82% (dry basis), and were within the acceptable limit of 10% dry basis for good storage stability.