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Spray drying technology for the production and processing of microencapsulated omega-3 fish oil with egg powder
Get PDFProtein with essential amino acids is required for recovering, repairing, and building muscles after intensive exercise. A powder produced with egg white (EW) (high quality protein) and fish oil (menhaden (Brevoortia patronus) (MO) oil or salmon oil (SO)) with high DHA and EPA content should be particularly beneficial for athletes. The objective of this study was to develop microencapsulated omega-3 fatty acids fortified EW powders. Two stable emulsions were prepared with 3.43% (MO) or (SO), 56.21% EW, and 40.36% water (E-MO-EW and E-SO-EW). An EW with water solution (without fish oil) (E-EW) was prepared as a control. Two emulsions (E-MO-EW; E-SO-EW) and E-EW solution were separately spray dried at 130, 140, and 150 oC inlet air temperatures producing three microencapsulated menhaden oil fortified EW powders, three microencapsulated salmon oil fortified EW powders, and three egg white powders (dried E-EW). Physical and chemical properties of E-EW, E-MO-EW and E-SO-EW were determined and the energy used to spray dry them was estimated. The powders were analyzed for color, fatty acids methyl esters (FAME), protein, fat, moisture, ash, amino acid profile, minerals, microstructure and particle size. Microencapsulated efficiency (ME) was estimated only for microencapsulated fish oil fortified EW powders. Triplicate experiments were conducted and data statistically analyzed (á=0.05). The actual production rate of powders ranged from 0.056 to 0.060 (kg dry solids/h). More energy was used to spray dry E-EW, E-MO-EW, and E-SO-EW at 150°C than at 130 and 140oC inlet air temperature. The inlet air temperature did not affect the EPA or DHA content of MO and SO or the microencapsulation efficiency. The protein content of the oil fortified powders was lower than that of the dried E-EW powders. Leucine was the main essential amino acid found in all the powders. Most of the powders’ particles ranged in size from 20 to 30 µm. The study demonstrated that high quality egg white protein with omega-3 can be produced by microencapsulation. Oil fortified egg white powders could provide benefits for athletes who do high intensity exercise. This study also identifies opportunities for development of microencapsulated omega-3 fatty acids fortified egg white powders
Developing Co-current and Counter-current Spray Drying Computational Fluid Dynamics (CFD) Simulation Studies to Predict the Quality of Microencapsulated Fish Oil with Egg White Hydrolysates Powders
Get PDFEggs are an excellent source of high quality protein containing all essential amino acids (EAA) including leucine. Food-grade protein hydrolysates can enhance the growth of lactic acid bacteria (LAB). Thermal degradation of bioactives normally occurs during microencapsulation by spray drying. Spray drying modeling using computational tools is essential to engineer new food powders and to minimize and thermal degradation of bioactives. The first chapter of this work discusses the optimization of an enzymatic process in terms of reaction temperature, pH, enzyme:substrate ratio, and reaction time using a response surface methodology (RSM) to produce food-grade protein hydrolysates from egg whites (EWH). Resulting EWH produced with proteases from Aspergillus oryzae contained all EAA and showed high antioxidant activity. The EWH were evaluated as a nitrogen source in MRS media for the growth of L. plantarum, L. acidophilus, and L. reuteri. MRS containing EWH had similar performance to that of conventional MRS and produced higher cell yields and better quality of biomass than MRS containing dried egg white proteins. Three-dimensional computational fluid dynamics (CFD) simulations were performed to study the effect of co-current and counter-current spray drying configurations on the quality of microencapsulated fish oil with EWH powders in the last section of this work. Also, the separation of powder particles from drying air at the spray dryer’s cyclone separator was evaluated using CFD. CFD models predicted the drying air flow pattern, particle histories including temperature, residence times (RT), moisture content and particle size of the microencapsulated powders. Predicted moisture content of powders was lower than measured values; however, the predicted mean particle sizes were similar to the measured values. Lower lipid oxidation and microstructure degradation was observed in emulsions dried at 130°C inlet air temperature at feeding rates of 1.0 Kg/h and under counter-current spray drying conditions. The 3D-CFD model predicted lower RT (s) for emulsions dried in counter-current compared to co-current spray drying configurations. The study demonstrated that EWH can be enzymatically produced and can be used as an effective nitrogen source in MRS media. Also, 3D-CFD spray drying modeling can be effectively used to study the moisture evaporation and to predict the final quality of spray dried powders
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Growth kinetics and lactic acid production of Lactobacillus plantarum NRRL B-4496, L. acidophilus NRRL B-4495, and L. reuteri B-14171 in media containing egg white hydrolysates
No full textThe objective of this study was to assess the performance of fermentation media containing egg white hydrolysates (EWH) and/or dried egg white (DEW) with standard MRS media on the growth of lactic acid bacteria (LAB) Lactobacillus plantarum NRRL B-4496, L. acidophilus NRRL B-449, and L. reuteri B-14171. Four fermentation media for growing LAB were evaluated: (1) standard MRS media, (2) MRS with no nitrogen source (MRSN), (3) MRSN with EWH (MRSN-EWH), and (4) MRSN with DEW (MRSN-DEW). The fermentation media were incubated with LAB at 37 °C for 24 h and periodically sampled to obtain growth curves, pH, and titratable acidity. The results showed that EWH had higher amounts of free amino acids compared to DEW. Threonine and leucine were the predominant free amino acids found in EWH. MRSN-EWH was better at promoting the growth of L. acidophilus NRRL B-449 and L. reuteri B-14171 in terms biomass production, maximum growth rate and titratable acidity than MRS. MRS and MRSN-EWH media supported greater cell biomass yields than MRSN and MRSN-DEW for L. plantarum NRRL B-4496. This study showed that egg white hydrolysates can be used in fermentation media to enhance the growth of probiotic lactic acid bacteria
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Use of an Adsorption Process for Purification of Pollock‐Oil‐Based Biodiesel Comprises Methyl Esters
No full textThe quality of biodiesel from crude pollock oil and the effect of a purification process on the physicochemical properties of pollock oil biodiesel were evaluated. Unpurified pollock oil (PO) was transesterified to biodiesel from pollock oil (BPO) using methyl alcohol (1:6 molar ratio) and NaOH (1 % w/w of the oil weight); and the resulting fatty acids methyl esters (FAME) were purified with 10 % (w/w) activated earth to yield purified biodiesel from pollock oil (PBPO). The samples were evaluated for yield, FAME composition, free fatty acids (FFA), peroxides value (PV), moisture, bulk density, cloud point, flash point, free and total glycerin, color, rheological properties, and minerals. BPO and PBPO were evaluated for the kinetics of lipid oxidation. The transesterification and purification processes had no effect on the FAME composition of PO. The yield of PBPO was significantly (P \u3c 0.05) reduced after the transesterification and purification processes. Moreover, the transesterification process significantly (P \u3c 0.05) reduced the FFA, moisture, bulk density, flash point, total glycerides, redness, viscosity, arsenic and silicon content in PO. Meanwhile, the purification process significantly (P \u3c 0.05) reduced the PV, redness, and sulfur content of BPO. The flash point of BPO was significantly (P \u3c 0.05) increased by the purification process from 79 to 84°C. PO, BPO, and PBPO behaved as non-Newtonian and Newtonian fluids at 0 and 25°C, respectively. BPO showed a lower oxidation rate and activation energy compared to those of PBPO. BPO and PBPO met the ASTM biodiesel standard D6751 for moisture, bulk density, cloud point, free and total glycerin, Na, P, and S. The study demonstrated that high viscosity crude pollock oil could be converted into low viscosity purified pollock oil biodiesel. © 2012 AOCS
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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