6 research outputs found

    Characterization of Eggshells Nanocatalyst: Synthesized by Bottom-Up Technology

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    The sol-gel technique was used to prepare the nanocatalyst from waste egg shells for the production of yellow oleander biodiesel. In this study, the physicochemical and catalytic properties of the nanocatalysts were investigated using: X-ray fluorescence spectrometry (XRF), transmission electron microscopy (TEM), the Barrett-Joyner-Halenda (BJH) model to quantify the pore structure of the samples, and Brunauer-Emmett-Teller (BET) to calculate the exact surface area were the techniques used. The results of the EDX, and XRF analysis showed that the synthesized nanocatalyst was majorly CaO. At 90.46 ± 1.73%, this was higher than the control for incinerated eggshells. From TEM images the particles were spherical in shape with particle sizes ranging from ≈ 7 to 41 nm. BET analysis results indicated that the nanocatalyst was mesoporous with surface area, average pore diameter, and pore volume was; 5.54 ± 0.48 m2/g, 18.57 ± 2.16 nm, and ≈ 0.016 ± 0.0 – 0.017 ± 0.0 cm³/g, respectively. The surface area to volume ratios were 3.27 ± 108 m-1, 2.52 ± 108, and 1.95 ± 108 m-1, respectively. Incinerated eggshells highest followed the synthesized nanocatalyst and CaO, respectively. The synthesized eggshell nanocatalyst was found to be a potential nanocatalyst

    Characterization of Eggshells Nanocatalyst: Synthesized by Bottom-Up Technology

    Get PDF
    The sol-gel technique was used to prepare the nanocatalyst from waste egg shells for the production of yellow oleander biodiesel. In this study, the physicochemical and catalytic properties of the nanocatalysts were investigated using: X-ray fluorescence spectrometry (XRF), transmission electron microscopy (TEM), the Barrett-Joyner-Halenda (BJH) model to quantify the pore structure of the samples, and Brunauer-Emmett-Teller (BET) to calculate the exact surface area were the techniques used. The results of the EDX, and XRF analysis showed that the synthesized nanocatalyst was majorly CaO. At 90.46 ± 1.73%, this was higher than the control for incinerated eggshells. From TEM images the particles were spherical in shape with particle sizes ranging from ≈ 7 to 41 nm. BET analysis results indicated that the nanocatalyst was mesoporous with surface area, average pore diameter, and pore volume was; 5.54 ± 0.48 m2/g, 18.57 ± 2.16 nm, and ≈ 0.016 ± 0.0 – 0.017 ± 0.0 cm³/g, respectively. The surface area to volume ratios were 3.27 ± 108 m-1, 2.52 ± 108, and 1.95 ± 108 m-1, respectively. Incinerated eggshells highest followed the synthesized nanocatalyst and CaO, respectively. The synthesized eggshell nanocatalyst was found to be a potential nanocatalyst

    Strategies for the enzymatic enrichment of PUFA from fish oil

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    A journal Article by Dr. Betty Mbatia, a Faculty in the School of PharmacyPUFA from oil extracted from Nile perch viscera were enriched by selective enzymatic esterification of the free fatty acids (FFA) or by hydrolysis of ethyl esters of the fatty acids from the oil (FA-EE). Quantitative analysis was performed using RP-HPLC coupled to an evaporative light scattering detector (RP-HPLC-ELSD). The lipase from Thermomyces lanuginosus discriminated against docosahexaenoic acid (DHA) most, resulting in the highest DHA/DHA-EE enrichment while lipase from Pseudomonas cepacia discriminated against eicosapentaenoic acid (EPA) most, resulting in the highest EPA/EPA-EE enrichment. The lipases discriminated between DHA and EPA with a higher selectivity when present as ethyl esters (EE) than when in FFA form. Thus when DHA/EPA were enriched to the same level during esterification and hydrolysis reactions, the DHA-EE/EPA-EE recoveries were higher than those of DHA/EPA-FFA. In reactions catalysed by lipase from T. lanuginosus, at 26 mol% DHA/DHA-EE, DHA recovery was 76% while that of DHA-EE was 84%. In reactions catalysed by lipase from P. cepacia, at 11 mol% EPA/EPA-EE, EPA recovery was 79% while that of EPA-EE was 92%. Both esterification of FFA and hydrolysis of FA-EE were more effective for enriching PUFA compared to hydrolysis of the natural oil and are thus attractive process alternatives for the production of products highly enriched in DHA and/or EPA. When there is only one fatty acid residue in each substrate molecule, the full fatty acid selectivity of the lipase can be expressed, which is not the case with triglycerides as substrates

    Anti-Oxidative Potential of Honey and Ascorbic Acid in Yoghurt Fortified With Omega-3 Fatty Acids

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    A Journal Article by Dr. Betty Mbatia, a Lecturer in the Faculty of Pharmacology and Health Sciences at USIU - AfricaProcessing of Nile perch (Lates niloticus), a commercial fish in Eastern Africa; results in omega-3 polyunsaturated fatty acids (PUFA) rich by-products. Oil derived from such by-products can be incorporated in commonly consumed foods; however, these fatty acids are highly susceptible to oxidation. Honey and ascorbic acid are natural anti-oxidants that could play a role in preventing lipid oxidation. In the current study, omega-3 rich oil was extracted from L. niloticus viscera and added to yoghurt samples. The aim of the study was to investigate the biochemical and anti-oxidative parameters in honey and lemon juice and use them as antioxidants in the fortified yoghurt samples. Stability of the fortified yoghurt was monitored over one month storage period. Ascorbic acid Equivalent Antioxidant Capacity (AEAC) of lemon juice and honey were 312 ± 2.34 and 197 ± 3.65 mg/L, respectively. The DPPH radical scavenging activity showed that honey (86.16± 1.43%) tended to be highly active in the reaction with DPPH compared to lemon juice (71.29± 3.52%).After four weeks of storage, the peroxide value (PV), anisidine value (AV) and (free fatty acid) (FFA) contents were within the acceptable range with the honey fortified sample being most stable. The ascorbic acid content was highest in lemon juice fortified samples (30 mg/100g) while in honey fortified samples were below 1mg/100g. The pH in all the samples decreased slightly over time. Honey and lemon juice are therefore good natural anti-oxidants and their anti-oxidative potential can be utilized in the prevention of lipid oxidation in omega-3 fortified yoghurts

    Development and Sensory Evaluation of Omega-3-Rich Nile Perch Fish Oil-Fortified Yogurt

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    Nile perch (Lates niloticus) is a major fish species in East Africa and its processing produces sufficient amounts of by-products containing significant amounts of long-chain polyunsaturated fatty acids (PUFAs). Due to the health benefits associated with PUFAs, they can be incorporated into commonly consumed foods such as yoghurt. This study is aimed at developing an omega-3-rich functional yoghurt and evaluating its quality and acceptability. Omega-3-rich fish oils were obtained from Nile perch fat pads in the presence and absence of a commercial food grade enzyme Alcalase. Recovery of omega-3-rich fish oil was done by centrifugation at 1000×g at room temperature. The peroxide value (PV), anisidine value (AV), total oxidation (TOTOX), and free fatty acids (FFA) were some of the quality parameters investigated. Natural yoghurt (150 ml) was prepared and spiked with 3.5 g of omega-3-rich Nile perch oil. To mask the fishy flavor and taste, four different flavors were used and sensory evaluation of the yoghurt samples was performed. The liberation of Nile perch fish oil in the absence of Alcalase gave better yield (60.7% wet weight), while the use of Alcalase gave lower yields (48.3% wet weight). Assessment of the quality of the extracted fish oils showed that all parameters were within the required limits. Sensory characterization by a panel of students showed that passion and strawberry flavors were the most liked with mean values of 4.65 and 4.625, respectively. This study revealed that substantial amounts of omega-3-rich fish oil can be extracted from Nile perch fish pads in the absence of exogenous enzymes. Fortification of yoghurt with omega-3-rich Nile perch fish oils is an approach towards increasing omega-3 intake within the Kenyan population and globally
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