Journal articles on the topic 'Milk concentration permeate'
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Lakstina, Jana, Inese Aboltina, Liga Vanaga, Inga Ciprovica, Daina Jonkus, Jelena Zagorska, and Ingmars Cinkmanis. "The Novel Solution for Acid Whey Permeate Application in Animal Feeding." Rural Sustainability Research 44, no. 339 (December 1, 2020): 1–7. http://dx.doi.org/10.2478/plua-2020-0011.
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AbstractThe experiment was conducted to analyse the effect of fermented acid whey permeate on milk yield and composition in the lactating cows. Propionic acid bacteria and their metabolites have been used in the lactating cows feeding over decades, primarily to improve growth performance, feed conversation and milk production efficiency. Two groups of the lactating cows were arranged in the study: control group (n=50) and experimental group (n=50). Experimental group’s animals received 0.5 L of fermented whey permeate daily. Acid whey permeate was inoculated with the freeze-dried PS-4 (Propionibacterium freudenreichii subsp. shermanii, Chr.Hansen, Denmark) starter and fermented anaerobically for 48 hours at 20±2 oC. Fat, protein, lactose and total solids concentration in acid whey permeate and fermented acid whey permeate was analysed by the standard methods, but propionic acid was detected by HPLC. Milk composition and quality indices were determined at the beginning of the study and each month during 6 months period. At the end of the study the feeding of fermented acid whey permeate was stopped, but milk composition and quality data were monitored additionally after one month. Milk fat, protein, lactose, total solids, urea concentration and somatic cell count were analysed by a near infrared spectroscopy.The variability in milk composition and quality data across trial was greater in the experiment group than in the control. Milk fat and somatic cell count were significantly different (p<0.05) than other studied parameters in the experimental group cows’ milk. Milk yield and lactose concentration were tended to increase during feeding of fermented acid whey permeate in the lactating cows without significant differences between control and experimental groups. Fermented acid whey permeate as feed supplement improves energy metabolism for dairy cows which results in the higher milk yield and fat concentration.
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Dutra Rosolen, Michele, Adriano Gennari, Giandra Volpato, and Claucia Fernanda Volken de Souza. "Lactose Hydrolysis in Milk and Dairy Whey Using Microbial β-Galactosidases." Enzyme Research 2015 (October 26, 2015): 1–7. http://dx.doi.org/10.1155/2015/806240.
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This work aimed at evaluating the influence of enzyme concentration, temperature, and reaction time in the lactose hydrolysis process in milk, cheese whey, and whey permeate, using two commercial β-galactosidases of microbial origins. We used Aspergillus oryzae (at temperatures of 10 and 55°C) and Kluyveromyces lactis (at temperatures of 10 and 37°C) β-galactosidases, both in 3, 6, and 9 U/mL concentrations. In the temperature of 10°C, the K. lactis β-galactosidase enzyme is more efficient in the milk, cheese whey, and whey permeate lactose hydrolysis when compared to A. oryzae. However, in the enzyme reaction time and concentration conditions evaluated, 100% lactose hydrolysis was not reached using the K. lactis β-galactosidase. The total lactose hydrolysis in whey and permeate was obtained with the A. oryzae enzyme, when using its optimum temperature (55°C), at the end of a 12 h reaction, regardless of the enzyme concentration used. For the lactose present in milk, this result occurred in the concentrations of 6 and 9 U/mL, with the same time and temperature conditions. The studied parameters in the lactose enzymatic hydrolysis are critical for enabling the application of β-galactosidases in the food industry.
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EL-GAZZAR, FATHY E., HANS F. BOHNER, and ELMER H. MARTH. "Growth of Listeria monocytogenes at 4, 32, and 40°C in Skim Milk and in Retentate and Permeate from Ultrafiltered Skim Milk." Journal of Food Protection 54, no. 5 (May 1, 1991): 338–42. http://dx.doi.org/10.4315/0362-028x-54.5.338.
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Pasteurized skim milk and retentate (concentrated fivefold or twofold by volume) and permeate from ultrafiltered skim milk were inoculated with Listeria monocytogenes strains California or V7 and incubated at 4, 32, or 40°C. Changes in populations of the pathogen were determined, growth curves were derived, and generation times and maximum populations calculated for each combination of strain, product, and temperature. Both strains grew faster and achieved higher (ca. 1 to 2 orders of magnitude) populations at 4°C in retentate of either concentration than in skim milk. The pathogen grew in permeate at 4°C and attained maximum populations of ca. 106 to 107/ml. Tyndallized samples of skim milk and retentate and permeate from ultrafiltered skim milk were inoculated with the same strains of L. monocytogenes and incubated at 32 or 40°C. Populations achieved by the pathogen at these temperatures, ca. 107 to 108/ml, were similar in skim milk, retentate, and permeate.
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Pouliot, Yves, Marcel Boulet, and Paul Paquin. "Observations on the heat-induced salt balance changes in milk I. Effect of heating time between 4 and 90°C." Journal of Dairy Research 56, no. 2 (May 1989): 185–92. http://dx.doi.org/10.1017/s0022029900026406.
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SummaryMilk permeate was separated at various temperatures by means of a hollow fibre ultrafiltration unit coupled to a stainless steel heat exchanger. Milk samples conditioned at 4°C were heated to 20, 40, 60, 80, 85 or 90°C prior to ultrafiltration. Ca, P, Mg, Na, K and citrate concentrations were measured in the permeate samples. Ca and P contents of the permeate decreased as the temperature increased. The pH was measured after cooling the permeate to room temperature. Smaller losses of Mg and citrate were also observed with increase in temperature. Na and K levels were not affected. A two-step time-concentration relationship was apparent for the species under study. An initial sharp decrease in concentration occurred in the first minute of holding time and was followed by a slower reaction. The possible occurrence of a two-step mechanism in the heat-induced salt balance changes is discussed. Dicalcium phosphate precipitation is believed to be coupled with tricalcium citrate precipitation upon heating.
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Paseephol, Tatdao, Darryl M. Small, and Frank Sherkat. "Lactulose production from milk concentration permeate using calcium carbonate-based catalysts." Food Chemistry 111, no. 2 (November 2008): 283–90. http://dx.doi.org/10.1016/j.foodchem.2008.03.051.
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Arunkumar, Abhiram, and Mark Etzel. "Milk Protein Concentration Using Negatively Charged Ultrafiltration Membranes." Foods 7, no. 9 (August 28, 2018): 134. http://dx.doi.org/10.3390/foods7090134.
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In this work, milk protein concentrate (MPC) was made using wide-pore negatively charged ultrafiltration membranes. The charged membranes were used for a six-fold volume concentration of skim milk and subsequent diafiltration to mimic the industrial MPC process. The charged 100 kDa membranes had at least a four-fold higher permeate flux at the same protein recovery as unmodified 30 kDa membranes, which are currently used in the dairy industry to make MPC. By placing a negative charge on the surface of an ultrafiltration membrane, the negatively charged proteins were rejected by electrostatic repulsion and not simply size-based sieving. Mass balance models of concentration and diafiltration were developed and the calculations matched the experimental observations. This is the first study to use wide-pore charged tangential-flow membranes for MPC manufacturing. Additionally, a unique mass balance model was applied, which accurately predicted experimental results.
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Abidin, Nur Sofuwani Zainul, Siti Aslina Hussain, and Siti Mazlina Mustapa Kamal. "Removal of Lactose from Highly Goat’s Milk Concentration through Ultrafiltration Membrane." Applied Mechanics and Materials 625 (September 2014): 596–99. http://dx.doi.org/10.4028/www.scientific.net/amm.625.596.
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Concentration of goat milk using cross-flow filtration unit with 10KDa molecular weight cut off (MCWO)-sized ultrafiltration membrane was examined under various operating conditions. The parameters to be optimized are trans-membrane pressure (TMP) and cross-flow velocity. Permeate flux is decreased with time due to fouling of the membrane. The localized membrane fouling may be reduced by increasing the feed flow rate and TMP to mitigate overall membrane fouling. By doing so, the transmission of lactose will also increase. The aim is to produce concentrated goat milk with minimal lactose content and thus high concentration of protein. Spray-drying method is used to convert the concentrated non-lactose milk obtained into milk powder. The milk powder then was characterized in terms of its surface particle, solubility, and nutritional content with the well-commercialized non-lactose milk. This project tackles understanding to minimize the deposition rates of particles on membrane by optimizing the involved parameters and be proved by comparing the yield obtained with well-commercialized non-lactose milk. Keywords:Goat’s milk, lactose intolerance, ultrafiltration, spray dry,membrane, concentration
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Paredes Valencia, Adriana, Alain Doyen, Scott Benoit, Manuele Margni, and Yves Pouliot. "Effect of Ultrafiltration of Milk Prior to Fermentation on Mass Balance and Process Efficiency in Greek-Style Yogurt Manufacture." Foods 7, no. 9 (September 4, 2018): 144. http://dx.doi.org/10.3390/foods7090144.
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Ultrafiltration (UF) can be used to concentrate yogurt to produce Greek-style yogurt (GSY) (UF-YOG), but this generates acid whey permeate, which is an environmental issue. However, when UF is applied before fermentation (UF-MILK), a nonacidified whey permeate is generated. For this study, two model GSYs (UF-YOG and UF-MILK) were produced to compare the composition, UF performance, and energy consumption of the two processes. For UF-MILK, skim milk was ultrafiltered with a 30 kDa spiral-wound UF membrane to achieve a 3× volume reduction factor (VRF). The retentate was fermented to a pH of 4.5. The UF-YOG process was the same except that regular yogurt was ultrafiltered. Both GSYs had similar protein (~10%) and solid content (~17%). As expected, lactic acid/lactate was not detected in UF-MILK permeate, while 7.3 g/kg was recovered from the UF-YOG permeate. Permeation flux values (11.6 to 13.3 L m−2 h−1) and total flux decline (47% to 50%) were constant during UF-MILK, whereas drastic decreases in these two membrane performance indicators (average flux: 38.5 to 10.9 L m−2 h−1; total flux decline: 2% to 38%) were calculated for UF-YOG. Moreover, for UF-YOG, UF membrane performance never recovered, even when drastic and repeated cleaning steps were applied. Energy consumption was 1.6 kWh/kg GSY and remained constant for UF-MILK, whereas it increased from 0.6 to 1.5 kWh/kg GSY for UF-YOG. Our results show that, although the composition of GSYs was similar for both processes, the UF step of yogurt concentration affected process efficiency due to drastic and permanent membrane fouling.
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Pouliot, Yves, Marcel Boulet, and Paul Paquin. "Experiments on the heat-induced salt balance changes in cow's milk." Journal of Dairy Research 56, no. 3 (May 1989): 513–19. http://dx.doi.org/10.1017/s0022029900029009.
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SummaryThe heat-induced changes in sait balance between the colloidal phase of milk and its serum were studied using an ultrafiltration technique. Milk permeate was isolated at the heating temperature by means of a hollow fibre ultrafiltration cartridge coupled with a stainless steel heat exchanger unit. The milk samples initially at 4 °C were heated to 20, 40, 60, 80 or 90 °C. Ca, P, Mg and citrate contents of the permeates were determined. The decreases in Ca and P were proportional to the increase in temperature. Smaller losses in Mg and citrate were observed. An initial sharp decrease in concentration occurred within the first seconds of holding time and was followed by a slower and smaller decrease. The possible occurrence of a two-stage mechanism for the heat-induced salt precipitation is discussed. The precipitation of dicalcium phosphate is believed to occur together with some tricalcium citrate precipitation.
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CHANTAYSAKORN, PANITA, and R. L. RICHTER. "Antimicrobial Properties of Pepsin-Digested Lactoferrin Added to Carrot Juice and Filtrates of Carrot Juice." Journal of Food Protection 63, no. 3 (March 1, 2000): 376–80. http://dx.doi.org/10.4315/0362-028x-63.3.376.
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The objective of this study was to determine the antimicrobial activity of pepsin-digested lactoferrin added to carrot juice and filtrates prepared from carrot juice. Lactoferrin isolated from raw skim milk was digested by pepsin for 4 h at pH 3. The digest of lactoferrin was lyophilized, and the antimicrobial activity of the digests was determined in peptone-yeast-glucose broth, carrot juice, permeate from carrot juice, and the dialysate of carrot juice permeate using Esherichia coli (American Type Culture Collection strain 35343) as the test organism. Growth of E. coli and the inhibitory effect of the peptide were greater in peptone-yeast-glucose broth at pH 7 than at pH 4. The peptic digest of lactoferrin did not have antimicrobial properties in carrot juice at concentrations of less than 10 mg/ml of juice. Carrot juice was filtered through a membrane with a molecular weight rejection of 10,000 or 500 Da, and the permeate was dialyzed against distilled water. Growth of E. coli was delayed in the filtrate by 5 mg but not by 1 mg of the peptic digest of lactoferrin per ml of filtrate. Bacterial counts of the control and experimental samples were not significantly different after 24 h of incubation. The peptic digest of lactoferrin at a concentration of 5 mg of digest per ml of dialysate was bacteriostatic toward E. coli after 24 h of incubation at 23°C. Dialysis of permeate caused a percentage reduction in cation concentration in the permeate ranging from 69.23% (Co) to 99.32% (Na). The antimicrobial activity of lactoferrin added to carrot juice was probably inhibited by cations.
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Meyer, Patricia, Johannes Petermeier, Martin Hartinger, and Ulrich Kulozik. "Concentration of Skim Milk by a Cascade Comprised of Ultrafiltration and Nanofiltration: Investigation of the Nanofiltration of Skim Milk Ultrafiltration Permeate." Food and Bioprocess Technology 10, no. 3 (November 28, 2016): 469–78. http://dx.doi.org/10.1007/s11947-016-1836-5.
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McSweeney, David J., Valentyn Maidannyk, Sharon Montgomery, James A. O’Mahony, and Noel A. McCarthy. "The Influence of Composition and Manufacturing Approach on the Physical and Rehydration Properties of Milk Protein Concentrate Powders." Foods 9, no. 2 (February 22, 2020): 236. http://dx.doi.org/10.3390/foods9020236.
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This study investigated the physical and rehydration properties of milk protein concentrate (MPC) powders with five different protein contents (i.e., 38.9, 53.7, 63.6, 74.1, and 84.7%, w/w) prepared by recombining the ultrafiltration (UF) retentate and UF permeate of skim milk. Powder density and flowability increased, while the powder particle size decreased with decreasing powder protein content. The amount of non-wetting MPC powder decreased with decreasing protein content, demonstrating greater wettability for lower protein powders. At protein contents >65% (w/w), the dispersibility and solubility of the powders decreased significantly, likely due to the greater hydrophobic interactions between casein proteins and a lower concentration of lactose. Therefore, as the protein content of the MPC powders was decreased, their rehydration properties improved. The results obtained in this study provide novel insights into the relationship between the composition of recombined UF retentate and UF permeate streams on the subsequent powder particle size, density, and rehydration properties, and demonstrate that such powders possess similar properties to those prepared using conventional direct membrane filtration.
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KORNACKI, JEFFREY L., and ELMER H. MARTH. "Thermal Inactivation of Staphylococcus aureus in Retentates from Ultrafiltered Milk." Journal of Food Protection 52, no. 9 (September 1, 1989): 631–37. http://dx.doi.org/10.4315/0362-028x-52.9.631.
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Cells of Staphylococcus aureus strains 196E, 481, and 425 were thermally stressed at 56°C for 10 min in milk and enumerated on Plate Count Agar (PCA), Mannitol Salt Agar (MSA), and PCA with an overlay of MSA. PCA recovered more S. aureus 196E and 481 than did PCA/MSA, which recovered more than MSA. PCA/MSA recovered slightly more S. aureus 425 than did PCA, which recovered more than MSA. At 58°C, in order of decreasing heat resistance, the four strains of S. aureus originally isolated from food were 425 > 100 and 481 > 196E. Their D-values were 26,14,13, and 3.0 min, respectively. S. aureus 425 was more heat resistant in the stationary than in the log phase when heated at 58°C in whole milk. Heat resistance at 58°C increased overall during the stationary growth phase, but was fairly stable when the culture was from 17 to 25 h or from 41 to 49 h old. S. aureus 425 exhibited no consistent differences in heat resistance in concentrated (4X by volume) and unconcentrated skim or whole milk. Adjustments of protein (3.5–4.0% to 12.6–16%), milkfat (0.28–1.12% to 10%), and lactose (ca. 4.5–5.0% to ca. 14.5–15%) contents of milk and 4X (volume concentration) UF milk retentates afforded no significant thermal protection to S. aureus 425. Diafiltration of 4X skim milk reduced thermal protection of S. aureus 425 in the retentate over that of unconcentrated skim milk of the same lot when tested at 63 and 74°C. S. aureus 425 had greatest D-values (min) in skim milk (0.36 ± 0.05) and permeate (0.30 ± 0.14) followed by permeate from diafiltration (0.28 ± 0.06) when tested at 63°C.
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Al-Hatim, Raqad R., Ali K. Al-Rikabi, and Amal K. Ghadban. "The Physico-Chemical Properties of Bovine and Buffalo Whey Proteins Milk by Using Ultrafiltration Membrane Technology." Basrah J. Agric. Sci. 33, no. 1 (June 27, 2020): 122–34. http://dx.doi.org/10.37077/25200860.2020.33.1.10.
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The current study aims to prepare whey from bovine and buffalo fresh milk to make three types of cheese, namely: thermal, acidic and enzymatic. Afterward, whey proteins have been separated, then the concentration process of whey proteins has been conducted by using ultrafiltration membrane technology. Through the previous step, two products have been obtained; first, concentrated whey proteins which is called (Retentate), while the other is called (Permeate). Applying rotary evaporator, whey proteins are concentrated and then drying in two methods: spray-drying and freeze-drying in a form of white and soft powder. The chemical composition has been studied at each phase. The results show the separation, purification, and concentration of bovine and buffalo whey proteins by using ultrafiltration membrane technology. The results show that buffalo whey proteins produced by the method of enzymatic and dried with spray-drying are better than bovine whey protein. Finally, the results show a low ratio of lactose, salts and moisture content at the stages of filtration and concentration. The results present a high proportion of protein to 80 .and low ratio lactose and salt.
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Li, Zhibin, Dasong Liu, Shu Xu, Wenjin Zhang, and Peng Zhou. "Transmission of Major and Minor Serum Proteins during Microfiltration of Skim Milk: Effects of Pore Diameters, Concentration Factors and Processing Stages." Foods 10, no. 4 (April 18, 2021): 888. http://dx.doi.org/10.3390/foods10040888.
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Effects of pore diameters (100, 50, and 20 nm), concentration factors (1–8) and processing stages (1–5) on the transmission of major serum proteins (β-lactoglobulin and α-lactalbumin) and minor serum proteins (immunoglobulin (Ig) G, IgA, IgM, lactoferrin (LF), lactoperoxidase (LPO), xanthine oxidase (XO)) during ceramic microfiltration (MF) of skim milk were studied. Holstein skim milk was microfiltered at a temperature of 50 °C, a transmembrane pressure of 110 kPa and a crossflow velocity of 6.7 m/s, using a tubular single stainless steel module that consisted of three ceramic tubes, each with 19 channels (3.5 mm inner diameter) and a length of 0.5 m. For MF with 100 nm and 50 nm pore diameters, the recovery yield of major serum proteins in permeate was 44.3% and 44.1%, while the recovery yield of minor serum proteins was slightly less by 0%–8% than 50 nm MF. MF with 20 nm pore diameters showed a markedly lower (by 12%–45%) recovery yield for both major and minor serum proteins, corresponding with its lower membrane flux. Flux sharply decreased with an increasing concentration factor (CF) up to four, and thereafter remained almost unchanged. Compared to the decrease (88%) of flux, the transmission of major and minor serum proteins was decreased by 4%–15% from CF = one to CF = eight. With increasing processing stages, the flux gradually increased, and the recovery yield of both major and minor proteins in the permeate gradually decreased and reached a considerably low value at stage five. After four stages of MF with 100 nm pore diameter and a CF of four for each stage, the cumulative recovery yield of major serum proteins, IgG, IgA, IgM, LF, LPO, and XO reached 95.7%, 90.8%, 68.5%, 34.1%, 15.3%, 39.1% and 81.2% respectively.
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Kodinova, Siyka Dimitrova, and Mariya Atanasova Dushkova. "Effect of volume reduction ration on the concentration and retention factors during ultrafiltration of goat’s milk." Food Science and Applied Biotechnology 4, no. 1 (March 19, 2021): 86. http://dx.doi.org/10.30721/fsab2021.v4.i1.135.
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This experimental work aimed to study the effect of volume reduction ratio on the concentration and retention (selectivity) factors during ultrafiltration of goat’s milk with UF25-PAN polyacrylnitrile membrane. They were calculated on the basis of dry matter, totoal protein, fat and ash content in retentates and permeate at volume reduction ratios of 2 and 3. The results showed that the increase in the volume reduction ratio from 2 to 3 led to an increase in the concentration factors of dry matter - from 1.34 ± 0.05 to 1.87 ± 0.03, total proteins – from 1.70 ± 0.02 to 2.72 ± 0.06, fat – from 1.71 ± 0.03 to 2.71 ± 0.03, ash – from 1.13 ± 0.02 to 1.52 ± 0.02 (p < 0.05). At these conditions, the retention factor (selectivity) of ash increased from 37.40 ± 2.19% to 53.50 ± 2.21% (p < 0.05). There was no significant difference (p > 0.05) of the selectivity of the membrane according to the proteins when volume reduction ratio increased. The results showed that these two volume reduction ratios and this membrane could be successfully used for the production of yoghurts with improved quality making them an excellent functional food.
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Nath, Arijit, Burak Atilla Eren, Attila Csighy, Klára Pásztorné-Huszár, Gabriella Kiskó, László Abrankó, Attila Tóth, et al. "Production of Liquid Milk Protein Concentrate with Antioxidant Capacity, Angiotensin Converting Enzyme Inhibitory Activity, Antibacterial Activity, and Hypoallergenic Property by Membrane Filtration and Enzymatic Modification of Proteins." Processes 8, no. 7 (July 18, 2020): 871. http://dx.doi.org/10.3390/pr8070871.
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Liquid milk protein concentrate with different beneficial values was prepared by membrane filtration and enzymatic modification of proteins in a sequential way. In the first step, milk protein concentrate was produced from ultra-heat-treated skimmed milk by removing milk serum as permeate. A tubular ceramic-made membrane with filtration area 5 × 10−3 m2 and pore size 5 nm, placed in a cross-flow membrane house, was adopted. Superior operational strategy in filtration process was herein: trans-membrane pressure 3 bar, retention flow rate 100 L·h−1, and implementation of a static turbulence promoter within the tubular membrane. Milk with concentrated proteins from retentate side was treated with the different concentrations of trypsin, ranging from 0.008–0.064 g·L−1 in individual batch-mode operations at temperature 40 °C for 10 min. Subsequently, inactivation of trypsin in reaction was done at a temperature of 70 °C for 30 min of incubation. Antioxidant capacity in enzyme-treated liquid milk protein concentrate was measured with the Ferric reducing ability of plasma assay. The reduction of angiotensin converting enzyme activity by enzyme-treated liquid milk protein concentrate was measured with substrate (Abz-FRK(Dnp)-P) and recombinant angiotensin converting enzyme. The antibacterial activity of enzyme-treated liquid milk protein concentrate towards Bacillus cereus and Staphylococcus aureus was tested. Antioxidant capacity, anti-angiotensin converting enzyme activity, and antibacterial activity were increased with the increase of trypsin concentration in proteolytic reaction. Immune-reactive proteins in enzyme-treated liquid milk protein concentrate were identified with clinically proved milk positive pooled human serum and peroxidase-labelled anti-human Immunoglobulin E. The reduction of allergenicity in milk protein concentrate was enzyme dose-dependent.
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Goldar, Parisa, Mohammad Hadi Givianrad, and Akbar Shams. "Effect of ultrafiltered milk permeate and non-dairy creamer powder concentration on low phenylalanine yoghurt’s physicochemical properties during storage." Journal of Food Science and Technology 53, no. 7 (July 2016): 3053–59. http://dx.doi.org/10.1007/s13197-016-2278-9.
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Thum, Caroline, Valerie Weinborn, Daniela Barile, Warren C McNabb, Nicole C Roy, and Juliana Maria Leite Nobrega de Moura Bell. "Understanding the Effects of Lactose Hydrolysis Modeling on the Main Oligosaccharides in Goat Milk Whey Permeate." Molecules 24, no. 18 (September 10, 2019): 3294. http://dx.doi.org/10.3390/molecules24183294.
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Enzymatic hydrolysis of lactose is a crucial step to improve the efficiency and selectivity of membrane-based separations toward the recovery of milk oligosaccharides free from simple sugars. Response surface methodology was used to investigate the effects temperature (25.9 to 54.1 °C) and amount of enzyme (0.17 to 0.32% w/w) at 1, 2, and 4 h of reaction on the efficiency of lactose hydrolysis by Aspergillus oryzae β-galactosidase, preservation of major goat whey oligosaccharides, and on the de-novo formation of oligosaccharides. Lactose hydrolysis above 99% was achieved at 1, 2, and 4 h, not being significantly affected by temperature and amount of enzyme within the tested conditions. Formation of 4 Hexose (Hex) and 4 Hex 1 Hex and an increased de-novo formation of 2 Hex 1 N-Acetyl-Neuraminic Acid (NeuAc) and 2 Hex 1 N-Glycolylneuraminic acid (NeuGc) was observed in all treatments. Overall, processing conditions using temperatures ≤40 °C and enzyme concentration ≤0.25% resulted in higher preservation/formation of goat whey oligosaccharides.
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Rham, Olivier De, and Serge Chanton. "An empirical mathematical model of retentate composition in ultrafiltration of dairy products." Journal of Dairy Research 53, no. 2 (May 1986): 271–81. http://dx.doi.org/10.1017/s0022029900024870.
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SUMMARYAnalysis of retentates of milk or whey, ultrafiltered and diafiltered by a pilot batch process with DDS Lab module equipment or (whey only) ultrafiltered by an industrial continuous process showed that nitrogen and ionic contents could not be described mathematically by the use of any value of the retention coefficient K. Analytical data suggested a new concept called segregation for nitrogen and ions in which each of these components consists of a completely permeable fraction and a totally retained fraction that do not exchange. A segregation coefficient Y is then defined as the ratio of the totally retained fraction to the total concentration of the species in the product fed to the equipment. However, this concept does not apply to lactose, where the classic retention concept (K) is retained. The two models are equivalent when K = Y = 0 or K = Y = 1. A first mathematical expression of this model was elaborated for batch ultrafiltration and/or constant volume diafiltration. Another set of equations was established for industrial conditions. These empirical models predict the retentate and permeate composition at any time during processing as well as after drying. The fit of analytical data with computed values was generally fair, with K being 0·1–0·4 in the pilot plant, and 0·1 in the factory. The nitrogen Y value was ∼ 0·95 for milk, and 0·85 for whey. In whey, the calcium Y value varied greatly from 0·06–0·71 depending on the pH, citrate content and heat treatment; in milk it was fairly constant at 0·5 at pH 6·7–5·8.
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Khramtsov, A. G., and V. N. Sergeev. "Technological breakthrough of the agrarian-and-food innovations in dairy case for example of universal agricultural raw materials. Nanofiltration." Agrarian-And-Food Innovations 12 (December 25, 2020): 7–19. http://dx.doi.org/10.31208/2618-7353-2020-12-7-19.
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Aim. Consideration nanofiltration as a process of membrane technology – directed and controlled filtration of whey through special semipermeable partitions (membrane filters) with a pore size of 1-5 nm, carried out at a pressure of 0.7-4.0 MPa with the release of particles with a molecular weight of 0.5-1.0 kDa. Discussion. Nanofiltration allows you to separate the whey as a system by the size of the components – microparticles and macromolecules. In this case, from pre – separated, processed by microfiltration and ultrafiltration of whey to nanoconcentrate (retentate) pass almost all the compounds of whey, and in nanofiltrate (permeate) - only monovalent ions of mineral salts and partially some organic acids. Nanofiltration, in the logistics of molecular sieve separation of whey, takes over from ultrafiltration and is a harbinger of reverse osmosis. The theoretical foundations of the nanofiltration process are developed at a fairly good level. The basic element of the process is the membranes. Based on the conducted research, we can recommend the nanofiltration process for industrial processing of salted whey into milk sugar (lactose) and for concentrating whey and its ultrafiltrates before electrodialysis or ion exchange desalination. Nanofiltration is already widely used in the production of high-quality lactose (milk sugar). Considerable interest nanofiltration cottage cheese (acid) whey with the purpose of concentration, demineralization and sensory nanoconcrete for the enrichment of ice cream. Conclusion. Nanofiltration can be quite reasonably used for processing, within the framework of the Technological Breakthrough, universal agricultural raw materials – for example, whey and its ultrafiltrates – for the purpose of concentration, directed demineralization, lowering the level of organic acids and controlling sensorics. The resulting nanoconcentrate (retentate) can be used to scale functional products.
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Lindgaard-Jorgensen, Palle, Gert Holm Kristensen, and Martin Andersen. "Road Map Towards Zero Water Milk-processing Plants - Experiences from a Danish Public-Private Partnership." Environmental Management and Sustainable Development 7, no. 2 (March 27, 2018): 157. http://dx.doi.org/10.5296/emsd.v7i2.12893.
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A three-year public-private partnership project in Denmark, with participation of food and environment authorities, branch organizations, technology providers, universities and applied research organizations, mapped the water use and installed water-saving technologies in four cheese-producing dairy plants and a milk-processing plant with mixed dairy products.The objective of the work was: (i) to document that reuse of water in the participating milk processing plants did not compromise product safety, and (ii) to develop methodologies to select best technologies as well as monitoring and control procedures for milk processing.Different mapping approaches were tested: water meters with online data transmission, detailed mapping of all water uses and a mapping that focused on the water uses which were expected to have the largest water-saving potential.Based on the results of the water use mapping, water efficiency scenarios for the plants were developed, and solutions were selected according to their water-saving potential, applicability in the dairy sector, cost-efficiency and sustainability.Selected technologies were tested in full-scale in a number of dairy processes, including reuse and increased efficiency in utilities and cleaning operations, optimization and renewal of milk-processing operations, reuse of permeate from RO filtration for concentration of whey and reuse of dairy waste water in utility functions. The investment costs for the installation of technologies were recorded as well as the actual water savings, energy savings and savings in labour time. The savings were substantial and could pay back the investment costs, often in less than a year - with the longest payback time being five years.A branch code was developed by the partnership providing guidance for water reuse in the dairy industry, including HACCP, monitoring and control procedures for reuse of water in CIP and other dairy processes and for storage and reuse of water from whey and milk concentration. A dairy, which applies the guidance and regulations in the branch code and adopts a combination of the technologies tested by the partnership, may save up to 60% of its present water use. The partnership also led to a vision for a zero water dairy, which would require; however, that new technologies and regulations would be developed and tested.
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Pierce, K. M., J. J. Callan, P. McCarthy, and J. V. O' Doherty. "Effects of high dietary concentration of lactose and increased soya-bean meal inclusion in starter diets for piglets." Animal Science 79, no. 3 (December 2004): 445–52. http://dx.doi.org/10.1017/s1357729800090317.
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AbstractA 3 X 2 factorial experiment was conducted to investigate the interactions between lactofeed 70 (LF70) (860 g/kg whey permeate, 140 g/kg soya-bean meal; Volac International, UK) and soya-bean meal (SBM) or dried skim milk (DSM) in piglet diets. Three hundred and thirty-six piglets were selected after weaning at 21 days with an initial live weight of 6-35 kg. They were blocked on the basis of live weight and within each block assigned to one of six dietary treatments. The pigs were offered the following starter diets : (1) 300 g/kg LF70 with 215 g/kg SBM and 100 g/kg DSM; (2) 200 g/kg LF70 with 215 g/kg SBM and 100 g/kg DSM; (3) 100 g/kg LF70 with 215 g/kg SBM and 100 g/kg DSM; (4) 300 g/kg LF70 with 325 g/kg DSM; (5) 200 g/kg LF70 with 325 g/kg DSM; (6) 100 g/kg LF70 with 325 g/kg DSM. The starter diets were offered for 25 days. Following this, a weaner diet (14 g/kg lysine, 14-5 MJ/kg digestible energy) was given for a period of 12 days. There was a significant interaction between LF70 level and protein source on average daily gain (ADG P < 0.001) and food conversion ratio (FCR P < 0.05) during the starter period. There was a linear increase in ADG and a linear improvement in FCR with increasing LF70 levels in diets with SBM. However, there was a linear decrease in ADG with increasing LF70 levels in diets with DSM. There was a significant interaction (P < 0.001) between LF70 level and protein source on average daily food intake (ADFI) during the starter period. At high LF70 levels, the inclusion of DSM reduced ADFl compared with SBM. However, there was no difference between DSM and SBM at the medium and low LF70 levels. There was a significant interaction between LF70 level and protein source in organic matter digestibility (OMD) (P < 0.01) and gross energy digestibility (GED) (P < 0.01). The pigs offered diets containing DSM had a significantly lower OMD and GED at low LF70 levels compared with pigs offered diets containing SBM. However, the inclusion of DSM had no significant effect on OMD or GED at the medium and high LF70 levels. There was a quadratic response in nitrogen digestibility (ND) with increasing concentrations of LF70 (P < 0.05). There was an increase in ND to 200 g/kg LF70 inclusion, however there was no further increase in ND above 200 g/kg LF70 inclusion. In conclusion, increasing the inclusion of lactofeed from 100 g/kg to 300 g/kg in starter diets where soya-bean meal comprised the principle protein source improved food efficiency and increased daily gain and daily food intake when compared with diets where dried skim milk comprised the principle protein source.
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GÉSAN-GUIZIOU, GENEVIÈVE, EVELYNE BOYAVAL, and GEORGES DAUFIN. "Nanofiltration for the recovery of caustic cleaning-in-place solutions: robustness towards large variations of composition." Journal of Dairy Research 69, no. 4 (November 2002): 633–43. http://dx.doi.org/10.1017/s0022029902005757.
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In the dairy industry re-use and multi-use cleaning-in-place (CIP) systems are operated by circulating chemicals and water without taking the equipment apart. The solutions, which become polluted due to the removal of fouling compounds, are drained periodically when they are considered to be too polluted. This work shows the large variations in composition (pollution, surface tension, etc) of the industrial caustic solutions coming from milk standardization and pasteurization plant CIP throughout their life time (7 days) and from 1 week to another. The work is also intended to show how nanofiltration (1 kg mol−1 molecular weight cut-off) was robust and performed well, with good recovery of caustic solutions, even when faced with large variations of solutions composition: high caustic yield, permeation flux (J) in the range 42–110 l h−1 m−2, average chemical oxygen demand (COD) reduction equal to 0.58 and low surface tension change. Equations have been established for the prediction of J as a function of initial membrane hydraulic resistance (Rm) caustic concentration, volume reduction ratio (VRR) and initial soluble COD. When VRR increased, both J and pollution retention decreased despite the increase in irreversible fouling induced by the increase of soluble pollution concentration in retentate . The higher the initial soluble COD, the sharper the decrease in J vs. VRR. Since irreversible fouling was usually small (0.1–3.4×1013 m−1, that is to say of the same order of magnitude as Rm), the membrane cleaning could be efficiently performed by using single phase sodium hypochlorite alternately with a more expensive acid–base cleaning sequence. The obtained permeate was a clear regenerated cleaning solution with low soluble COD (0.2–3.5 g/l) and surface tension (56–30 mJ m−2) which could be successfully exploited owing to its cleaning potential.
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Kaombe, Divina D., Yanhong Du, and Michael J. Lewis. "Mineral partitioning in milk and milk permeates at high temperature." Journal of Dairy Research 79, no. 1 (September 13, 2011): 1–6. http://dx.doi.org/10.1017/s0022029911000616.
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The soluble phase of milk was separated at 20 and 80°C using ultrafiltration. The resulting permeates were then subjected to further ultrafiltration and dialysis at close to these two temperatures. It was found that pH, Ca2+ and soluble Ca decreased as the separation temperature increased both in original UF permeates and in dialysates obtained from these permeates, but P decreased only slightly. The major reason for these changes was due to the precipitation of calcium phosphate/citrate complexes onto the casein micelle with concomitant release of H+. The pH of both permeates and dialysates from milk at 20°C were slightly higher than for milk. When UF permeates collected at 20 and 80°C, were each dialysed at both these temperatures, the dialysate collected at 80°C showed much less temperature dependence for pH and ionic calcium compared with that collected at 20°C. This is in contrast to milk, which shows considerable temperature dependence for pH and ionic calcium. Further experiments revealed that the pH and Ca2+ concentration of permeates showed high temperature dependence above the temperature at which they were separated, but a much lower temperature dependence below that temperature. These findings suggest that dialysis and UF of milk at high temperature provide the best means yet for estimating the pH and ionic calcium of milk at that temperature.
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Zokaityte, Egle, Vita Lele, Vytaute Starkute, Paulina Zavistanaviciute, Darius Cernauskas, Dovile Klupsaite, Modestas Ruzauskas, et al. "Antimicrobial, Antioxidant, Sensory Properties, and Emotions Induced for the Consumers of Nutraceutical Beverages Developed from Technological Functionalised Food Industry By-Products." Foods 9, no. 11 (November 6, 2020): 1620. http://dx.doi.org/10.3390/foods9111620.
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This study aims to develop nutraceutical beverages containing food processing by-products in their formulation, and determine the opinion of consumers. This is done by testing whether they know that the main ingredients of the product are by-products, performing an overall acceptability test of the developed beverages, and evaluating the emotions induced by the newly developed beverages for consumers. The main ingredients used for the preparation of added-value beverages were fermented milk permeate (containing galactooligosaccharides), extruded and fermented wheat bran (WB) (containing ≥6.0 log10 CFU g−1 viable antimicrobial properties showing lactic acid bacteria (LAB) strains), and different fruit/berry by-products (FBB) (as a source of compounds showing antioxidant properties). The definition of the quantities of bioactive ingredients was based on the overall acceptability of the prepared beverages, as well as on emotions induced in consumers by the tested beverages. Functional properties of the developed beverages were proofed by the evaluation of their antimicrobial and antioxidant properties, as well as viable LAB count during storage. Desirable changes in extruded and fermented WB were obtained: Fermentation reduced sugar concentration and pH in samples with predominant lactic acid isomer L(+). In addition, the viable LAB count in the substrate was higher than 6.0 log10 CFU g−1, and no enterobacteria remained. By comparing the overall acceptability of the beverages enriched with WB, the highest overall acceptability was shown for the samples prepared with 10 g of the extruded and fermented WB (7.9 points). FBB showed desirable antimicrobial activity: Shepherd inhibited—2, sea buckthorn—3, blueberries—5, and raspberries—7 pathogens from the 10 tested. Comparing different beverage groups prepared with different types of FBB, in most cases (except sea buckthorn), by increasing FBB content the beverages overall acceptability was increased, and the highest score (on average, 9.5 points) was obtained for the samples prepared with 5.0 and 7.5 g of blueberries FBB. Moreover, a very strong positive correlation (r = 0.8525) was found between overall acceptability and emotion “happy” induced in consumers by the prepared beverages enriched with extruded and fermented WB and FBB. By comparing the samples prepared with the addition of WB with samples prepared with WB and FBB, it was observed that most FBB increased total phenolic compounds (TPC) content (on average, by 9.0%), except in the case of samples prepared with sea buckthorn. A very high positive correlation (r = 0.9919) was established between TPC and antioxidant activity. Finally, it can be stated that the newly developed nutraceutical beverages were acceptable for consumers, induced positive emotions, and possessed desirable antimicrobial and antioxidant properties, while being prepared in a sustainable and environmentally friendly manner.
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Cooper, Peter, Keith D. Bolton, Sithembiso Velaphi, Nanda De Groot, Shahram Emady-Azar, Sophie Pecquet, and Philippe Steenhout. "Early Benefits of a Starter Formula Enriched in Prebiotics and Probiotics on the Gut Microbiota of Healthy Infants Born to HIV+ Mothers: A Randomized Double-Blind Controlled Trial." Clinical Medicine Insights: Pediatrics 10 (January 2016): CMPed.S40134. http://dx.doi.org/10.4137/cmped.s40134.
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The gut microbiota of infants is shaped by both the mode of delivery and the type of feeding. The gut of vaginally and cesarean-delivered infants is colonized at different rates and with different bacterial species, leading to differences in the gut microbial composition, which may persist up to 6 months. In a multicenter, randomized, controlled, double-blind trial conducted in South Africa, we tested the effect of a formula supplemented with a prebiotic (a mixture of bovine milk-derived oligosaccharides [BMOS] generated from whey permeate and containing galactooligosaccharides and milk oligosaccharides such as 3′- and 6′-sialyllactose) and the probiotic Bifidobacterium animalis subsp. lactis (B. lactis) strain CNCM I-3446 on the bifidobacteria levels in the gut of infants born vaginally or via cesarean section in early life. Additionally, the safety of the new formulation was evaluated. A total of 430 healthy, full-term infants born to HIV-positive mothers who had elected to feed their child beginning from birth (≤3 days old) exclusively with formula were randomized into this multicenter trial of four parallel groups. A total of 421 infants who had any study formula intake were included in the full analysis set (FAS). The first two groups consisted of cesarean-delivered infants assigned to the Test formula (n = 92) (a starter infant formula [IF] containing BMOS at a total oligosaccharide concentration of 5.8 ± 1.0 g/100 g of powder formula [8 g/L in the reconstituted formula] + B. lactis [1 × 10 7 colony-forming units {cfu}/g]) or a Control IF (n = 101); the second two groups consisted of vaginally delivered infants randomized to the same Test (n = 115) or Control (n = 113) formulas from the time of enrollment to 6 months. The primary efficacy outcome was fecal bifidobacteria count at 10 days, and the primary safety outcome was daily weight gain (g/d) between 10 days and 4 months. At 10 days, fecal bifidobacteria counts were significantly higher in the Test formula than in the Control formula group among infants with cesarean birth (median [range] log: 9.41 [6.30–10.94] cfu/g versus 6.30 [6.30–10.51] cfu/g; P = 0.002) but not among those with vaginal birth (median [range] log: 10.06 [5.93–10.77] cfu/g versus 9.85 [6.15–10.79] cfu/g; P = 0.126). The lower bound of the two-sided 95% confidence interval of the difference in the mean daily weight gain between the Test and Control formula groups was more than –3 g/d in both the vaginally and cesarean-delivered infants, indicating that growth in the Test formula-fed infants was not inferior to that of Control formula-fed infants. At 10 days and 4 weeks, the fecal pH of infants fed the Test formula was significantly lower than in those fed the Control formula, irrespective of mode of delivery: for vaginal delivery: 4.93 versus 5.59; P < 0.001 (10 days) and 5.01 versus 5.71; P < 0.001 (4 weeks); for cesarean delivery: 5.14 versus 5.65, P = 0.009 (10 days) and 5.06 versus 5.75, P < 0.001 (4 weeks). At 3 months, this acidification effect only persisted among cesarean-born infants. IF supplemented with the prebiotic BMOS and probiotic B. lactis induced a strong bifidogenic effect in both delivering modes, but more explicitly correcting the low bifidobacteria level found in cesarean-born infants from birth. The supplemented IF lowered the fecal pH and improved the fecal microbiota in both normal and cesarean-delivered infants. The use of bifidobacteria as a probiotic even in infants who are immunologically at risk is safe and well tolerated.
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Ochando-Pulido, J. M., G. Hodaifa, and A. Martínez-Ferez. "Permeate recirculation impact on concentration polarization and fouling on RO purification of olive mill wastewater." Desalination 343 (June 2014): 169–79. http://dx.doi.org/10.1016/j.desal.2014.03.025.
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Silva, Filipa A. L. S., Raquel Costa-Almeida, Licínia Timochenco, Sara I. Amaral, Soraia Pinto, Inês C. Gonçalves, José R. Fernandes, Fernão D. Magalhães, Bruno Sarmento, and Artur M. Pinto. "Graphene Oxide Topical Administration: Skin Permeability Studies." Materials 14, no. 11 (May 25, 2021): 2810. http://dx.doi.org/10.3390/ma14112810.
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Nanostructured carriers have been widely used in pharmaceutical formulations for dermatological treatment. They offer targeted drug delivery, sustained release, improved biostability, and low toxicity, usually presenting advantages over conventional formulations. Due to its large surface area, small size and photothermal properties, graphene oxide (GO) has the potential to be used for such applications. Nanographene oxide (GOn) presented average sizes of 197.6 ± 11.8 nm, and a surface charge of −39.4 ± 1.8 mV, being stable in water for over 6 months. 55.5% of the mass of GOn dispersion (at a concentration of 1000 µg mL−1) permeated the skin after 6 h of exposure. GOn dispersions have been shown to absorb near-infrared radiation, reaching temperatures up to 45.7 °C, within mild the photothermal therapy temperature range. Furthermore, GOn in amounts superior to those which could permeate the skin were shown not to affect human skin fibroblasts (HFF-1) morphology or viability, after 24 h of incubation. Due to its large size, no skin permeation was observed for graphite particles in aqueous dispersions stabilized with Pluronic P-123 (Gt–P-123). Altogether, for the first time, Gon’s potential as a topic administration agent and for delivery of photothermal therapy has been demonstrated.
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Macedo, Antónia, Joana Monteiro, and Elizabeth Duarte. "A Contribution for the Valorisation of Sheep and Goat Cheese Whey through Nanofiltration." Membranes 8, no. 4 (November 20, 2018): 114. http://dx.doi.org/10.3390/membranes8040114.
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The amount of cheese whey generated from the production of speciality sheep and goat cheese is significantly growing due to the acclaimed nutritional and medicinal benefits of the milk from these species. However, most of the cheese whey generated has no applications, thus giving rise to environmental problems. This work focuses on the study of the performance of the nanofiltration process for recovering the permeates of ultrafiltration from sheep and goat cheese whey. Nanofiltration experiments were carried out with membranes of nanofiltration (NF) in total recirculation and concentration modes, at 25 °C. Nanofiltration of the ultrafiltration permeates from sheep cheese whey was done at a pressure of 3.0 × 106 Pa and a circulation velocity of 1.42 m·s−1, until a volume concentration factor (VCF) of 2.5. Nanofiltration of the permeates from ultrafiltration of goat cheese whey was performed at a pressure of 2.0 × 106 Pa and a circulation velocity of 0.94 m·s−1, until a VCF of 2.0. From the results, it was concluded that osmotic pressure was the most important factor affecting the performance of the process. In both cases, the final permeates had a much lower organic load and its future use in the process of cheese making should be evaluated.
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Csighy, Attila, Andras Koris, and Gyula Vatai. "Diafiltration based cow’s milk partial demineralization by membrane filtration process – parameter and technology estimations." Progress in Agricultural Engineering Sciences 14, s1 (July 2018): 45–55. http://dx.doi.org/10.1556/446.14.2018.s1.5.
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Milk and dairy products contain a number of biological materials that are essential for the human body, for example proteins, lipids, vitamins and minerals. In this study the application of membrane filtration based milk partial demineralization is detailed. The main point of the partial demineralization is to reduce the monovalent ions (Na+, K+) but to keep the divalent ions (Ca2+, Mg2+) content. The experiments were carried out using laboratory ultra- and nanofiltration units. Comparing the separation behavior of the membranes it was found that the investigated membranes are suitable for the partial demineralization. The result of the Lowry test showed that the protein concentration is higher in the retentates of all membrane filtrations than in the permeates.
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Bottino, Aldo, Gustavo Capannelli, Antonio Comite, Camilla Costa, Raffaella Firpo, Anna Jezowska, and Marcello Pagliero. "Treatment of Olive Mill Wastewater through Integrated Pressure-Driven Membrane Processes." Membranes 10, no. 11 (November 11, 2020): 334. http://dx.doi.org/10.3390/membranes10110334.
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The disposal of wastewater resulting from olive oil production (olive mill wastewater, OMW) is a major issue for olive oil producers. This wastewater is among the most polluting due to the very high concentration of organic substances and the presence of hardly degradable phenolic compounds. The systems proposed for OMW treatment are essentially based either on conventional chemical-physical, biological and thermal processes, or on membrane processes. With respect to conventional methods, membrane processes allow to separate different species without the use of chemicals or heat. This work deals with the use of the integrated pressure-driven membrane processes for the treatment of OMW. They consist of a first stage (microfiltration, MF) in which a porous multichannel ceramic membrane retains suspended materials and produces a clarified permeate for a second stage (reverse osmosis, RO), in order to separate (and concentrate) dissolved substances from water. Laboratory scale experiments with different small flat sheet RO membranes were first carried out in order to select the most appropriate one for the successive bench scale tests with a spiral wound module having a large membrane surface. The aim of this test was to concentrate the dissolved substances and to produce water with low salinity, chemical oxygen demand (COD), and reduced phytotoxicity due to a low content of phenolic compounds. The trend of the permeate flux and membrane retention as a function of the volume concentration ratio was investigated. The influence of OMW origin and its aging on the membrane performance was also studied.
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Rodionov, D. A., S. I. Lazarev, K. K. Polyansky, E. V. Eckert, and D. L. Polushkin. "Analysis of experimental data on the kinetic characteristics of milk whey purification using ultrafiltration elements of BTU 05/2 type." Proceedings of the Voronezh State University of Engineering Technologies 82, no. 4 (January 20, 2021): 88–94. http://dx.doi.org/10.20914/2310-1202-2020-4-88-94.
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The paper presents the results of experimental data on the kinetic characteristics of ultrafiltration tubular elements, such as the output specific flow, retention coefficient, diffusion permeability coefficient, distribution coefficient. To study the purification of milk whey, we used tubular ultrafilters BTU 05/2 with membrane material fluoroplast (F), polyethersulfone (PESF), polysulfone (PS). For theoretical calculation of the retention coefficient, output specific flux, diffusion permeability coefficient, distribution coefficient, mathematical expressions were developed and empirical coefficients were obtained. The developed mathematical expression describes the experimental data with good reliability. The obtained experimental and calculated data can be used with high reliability in calculating mass-transfer fluxes of substances through a semi-permeable membrane, as well as in engineering methods for calculating and predicting efficiency, and using membrane processes for concentrating serum. The protein concentration in real milk whey was determined by formol titration. On the basis of the studies carried out, the dependence of the growth of the output specific flow on pressure was established, that the optimal pressure for concentrating milk whey on the ultrafiltration membranes we have chosen is 0.25 MPa. For three types of ultrafilters, the experimental value of the coefficient was within 99% for protein. For the theoretical calculation of the retention coefficient, a program in the MAXIMA language was developed and registered. Due to the method of applying the membrane to the reinforcing element, the membrane material polyethersulfone (PESF) and polysulfone (PS) have a substrate, due to which they sorb more substances on themselves, because of this, the diffusion permeability coefficient and the distribution coefficient are much higher than that of a filter element with membrane made of fluoroplastic (F), which does not have a substrate.
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Sheldon, M. S., P. J. Zeelie, and W. Edwards. "Treatment of paper mill effluent using an anaerobic/aerobic hybrid side-stream Membrane Bioreactor." Water Science and Technology 65, no. 7 (April 1, 2012): 1265–72. http://dx.doi.org/10.2166/wst.2012.007.
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This paper presents the design and operational performance data of an anaerobic/aerobic hybrid side-stream Membrane Bioreactor (MBR) process for treating paper mill effluent operated over a 6 month period. The paper mill effluent stream was characterized by a chemical oxygen demand (COD) range of between 1,600 and 4,400 mg/L and an average BOD of 2,400 mg/L. Despite large fluctuations in COD feed concentration, stable process performance was achieved. The anaerobic Expanded Granular Sludge Bed (EGSB) pre-treatment step effectively lowered the organic loading by 65 to 85%, thus lowering the MBR COD feed concentration to consistently below 750 mg/L. The overall MBR COD removal was consistent at an average of 96%, regardless of the effluent COD or changes in the hydraulic retention time (HRT) and organic loading rate (OLR). Combining a high-rate anaerobic pre-treatment EGSB with a Modified Ludzack–Ettinger (MLE) MBR process configuration produced a high quality permeate. Preliminary NF and RO results indicated an overall COD removal of around 97 and 98%, respectively.
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Hernandez, L. L., J. L. Collier, A. J. Vomachka, R. J. Collier, and N. D. Horseman. "Suppression of lactation and acceleration of involution in the bovine mammary gland by a selective serotonin reuptake inhibitor." Journal of Endocrinology 209, no. 1 (February 9, 2011): 45–54. http://dx.doi.org/10.1530/joe-10-0452.
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Serotonin (5-HT) is a homeostatic regulator of lactation. Selective 5-HT reuptake inhibitors (SSRI) are commonly prescribed pharmaceuticals that inhibit activity of the 5-HT reuptake transporter, increasing cellular exposure to 5-HT. Use of SSRIs has been shown to alter lactation performance in humans and 5-HT has been shown to reduce milk yield in cattle. However, it has not been determined how SSRI treatments affect the bovine mammary gland. We evaluated the effects of SSRI (fluoxetine (FLX)) administration on tight junctions (TJs) and milk protein gene expression in a lactogenic culture model, using primary bovine mammary epithelial cells (pBMEC). Additionally, we evaluated the effects of intramammary infusions of FLX and 5-hydroxytryptophan on milk production and TJ status in multiparous Holstein cows at dry-off. Treatment of pBMEC cultured on permeable membranes disrupted TJs, as measured by transepithelial resistance and immunostaining for zona occludens 1. Correspondingly, treatment of ‘3D’, collagen-embedded lactogenic cultures of pBMEC with FLX suppressed milk protein gene expression (α-lactalbumin and β-casein) in a concentration-dependent manner. Finally, intramammary treatment of Holstein cows with FLX resulted in an accelerated rate of milk decline. Additionally, TJ permeability increased in FLX-treated animals, as measured by plasma lactose and milk Na+ and K+ levels. Results of these experiments imply that SSRI administration accelerates the rate of mammary gland involution through disassembly of TJs and inhibition of milk protein gene expression in vitro and in vivo, leading to reduction of milk yield.
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Rokhati, Nur, Titik Istirokhatun, Nur ‘Aini Hamada, and Dwi Titik Apriyanti. "Membrane Technology Application for Fractionation Process to Obtain High Quality Glucosamine." Reaktor 20, no. 2 (June 30, 2020): 103–8. http://dx.doi.org/10.14710/reaktor.20.2.103-108.
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Glucosamine, monosaccharide from chitosan obtained from the chitin deacetylation process, has been used widely in various fields such as nutrition, pharmacy, and cosmetics. Glucosamine can be obtained from the hydrolysis of chitosan. Enzymatic hydrolysis provides the advantage of mild reaction conditions, environmentally friendly, and high yield. But until now, the separation of glucosamine from the chitosan hydrolysis fraction has been an obstacle. Ultrafiltration membranes offer an efficient filtration process because they do not require additional chemicals. The performance of ultrafiltration membranes was analyzed from the fractionation process of chitosan hydrolysis. The PES membranes in 10, 25, and 50 kDa were used to filter hydrolyzed Low Molecular Weight Chitosan (LMWC) in varied concentrations. The experiment was carried out in crossflow membrane module for flat sheet at room temperature in 1 bar. The permeate flux during filtration decreased rapidly at the initial and gradually over time because of fouling and concentration polarization. The more concentrated hydrolyzed LMWC solution resulted higher percentage of rejection up to almost 20% at the same membrane MWCO while higher MWCO resulted lower rejection percentage for the same hydrolyzed LMWC concentration. The FTIR spectrum of the used membranes of all types had absorption bands of glucosamine which proved that the fractionation process occurred. The time retention in HPLC chromatograms of glucosamine produced were similar with standard glucosamine. Thus, ultrafiltration could be applied for hydrolyzed LMWC fractionation process.Keywords: fractionation; glucosamine; LMWC; MWCO; ultrafiltration
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Kusworo, Tutuk Djoko, Danny Soetrisnanto, Cynthia Santoso, Tyas Dwi Payanti, and Dani Puji Utomo. "Hydrophylicity Enhancement of Modified Cellulose Acetate Membrane to Improve the Membrane Performance in Produced Water Treatment." MATEC Web of Conferences 156 (2018): 08003. http://dx.doi.org/10.1051/matecconf/201815608003.
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Produced water is a wastewater generated from petroleum industry with high concentration of pollutants such as Total Dissolved Solid, Organic content, and Oil and grease. Membrane technology has been currently applied for produced water treatment due to its efficiency, compact, mild and clean process. The main problem of produced water using membrane is fouling on the membrane surface which causes on low permeate productivity. This paper is majority focused on the improvement of anti-fouling performance through several modifications to increase CA membrane hydrophilicity. The membrane was prepared by formulating the dope solution consists of 18 wt-% CA polymer, acetone, and PEG additive (3 wt-%, 5 wt-%, and 7 wt-%). The membranes are casted using NIPS method and being irradiated under UV light exposure. The SEM images show that parepared membrane has asymmetric structure consist of dense layer, intermediete layer, and finger-like support layer. The filtration test shows that PEG addition increase the membrane hydrophilicity and the permeate flux increases. UV light exposure on the membrane improves the membrane stability and hydrophilicity. The imrpovement of membrane anti-fouling performance is essential to achieve the higher productivity without lowering its pollutants rejection.
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Ericson, Lars E., and Mikael Nilsson. "Deactivation of TSH receptor signaling in filter-cultured pig thyroid epithelial cells." American Journal of Physiology-Endocrinology and Metabolism 278, no. 4 (April 1, 2000): E611—E619. http://dx.doi.org/10.1152/ajpendo.2000.278.4.e611.
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Thyrotropin [thyroid-stimulating hormone (TSH)] receptor on-off signaling was studied in polarized monolayers of pig thyrocytes cultured on permeable support. Transepithelial resistance (R) and potential difference (PD) were used as parameters to monitor the effect of altered TSH concentrations on vectorial electrolyte transport. TSH induced rapid but long-lasting changes in R (decrease) and PD (increase) that were cAMP-dependent and related to enhanced transcellular conductance of sodium and chloride. Withdrawal of TSH from cultures prestimulated with TSH (0.1 mU/ml) for 48 h resulted in restitution of R to control level within 30 min. Such deactivation was markedly accelerated by mild trypsinization, which degraded receptor-bound ligand without affecting TSH receptor responsiveness or ion transporting capacity. Small alterations in the TSH concentration (0.01–0.1 mU/ml) were followed almost instantaneously by adjustments of R. In contrast, the reversal of R after acute TSH stimulation (30 min) and subsequent TSH washout was delayed for several hours independently of cell surface trypsinization. The observations indicate that, during continuous exposure to physiological concentrations, TSH exerts a close minute-to-minute surveillance of thyroid function and the rate-limiting step of deactivation is the dissociation of ligand from the TSH receptor at the cell surface. TSH-deprived cells briefly exposed to TSH are refractory to rapid deactivation, probably because of altered metabolism downstream of TSH receptor signal transduction.
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Cervantes, Fadia V., Sawssan Neifar, Zoran Merdzo, Javier Viña-Gonzalez, Lucia Fernandez-Arrojo, Antonio O. Ballesteros, Maria Fernandez-Lobato, Samir Bejar, and Francisco J. Plou. "A Three-Step Process for the Bioconversion of Whey Permeate into a Glucose-Free D-Tagatose Syrup." Catalysts 10, no. 6 (June 9, 2020): 647. http://dx.doi.org/10.3390/catal10060647.
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We have developed a sustainable three-stage process for the revaluation of cheese whey permeate into D-tagatose, a rare sugar with functional properties used as sweetener. The experimental conditions (pH, temperature, cofactors, etc.) for each step were independently optimized. In the first step, concentrated whey containing 180–200 g/L of lactose was fully hydrolyzed by β-galactosidase from Bifidobacterium bifidum (Saphera®) in 3 h at 45 °C. Secondly, glucose was selectively removed by treatment with Pichia pastoris cells for 3 h at 30 °C. The best results were obtained with 350 mg of cells (previously grown for 16 h) per mL of solution. Finally, L-arabinose isomerase US100 from Bacillus stearothermophilus was employed to isomerize D-galactose into D-tagatose at pH 7.5 and 65 °C, in presence of 0.5 mM MnSO4. After 7 h, the concentration of D-tagatose was approximately 30 g/L (33.3% yield, referred to the initial D-galactose present in whey). The proposed integrated process takes place under mild conditions (neutral pH, moderate temperatures) in a short time (13 h), yielding a glucose-free syrup containing D-tagatose and galactose in a ratio 1:2 (w/w).
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Quesnell, Rebecca R., Xiaobin Han, and Bruce D. Schultz. "Glucocorticoids stimulate ENaC upregulation in bovine mammary epithelium." American Journal of Physiology-Cell Physiology 292, no. 5 (May 2007): C1739—C1745. http://dx.doi.org/10.1152/ajpcell.00369.2006.
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Mammary epithelia produce an isotonic, low-Na+ fluid that is rich in nutrients. Mechanisms that account for the low electrolyte concentration have not been elucidated, although amiloride-sensitive ion transport has been reported in some situations. We hypothesized that corticosteroid exposure modulates epithelial Na+ channel (ENaC) expression and/or activity in bovine mammary epithelial cells. BME-UV cells were grown to confluent monolayers on permeable supports with a standard basolateral medium and apical medium of low-electrolyte, high-lactose composition that resembles the ionic composition of milk. Ion transport was assessed in modified Ussing flux chambers. Exposure to glucocorticoids (dexamethasone, cortisol, or prednisolone), but not aldosterone, increased short-circuit current ( Isc), a sensitive measure of net ion transport, whereas apical exposure to amiloride or benzamil reduced corticosteroid-induced Isc close to basal levels. Quantitative RT-PCR indicated a glucocorticoid-induced increase in mRNA for β- and γ-ENaC, whereas α-ENaC mRNA expression was only mildly affected. Exposure to mifepristone (a glucocorticoid receptor antagonist), but not spironolactone (a mineralocorticoid receptor antagonist), precluded both the corticosteroid-induced elevation in amiloride-sensitive Isc and the induced changes in β- and γ-ENaC mRNA. We conclude that Na+ movement across mammary epithelia is modulated by corticosteroids via a glucocorticoid receptor-mediated mechanism that regulates the expression of the β- and γ-subunits of ENaC. ENaC expression and activity could account for the low Na+ concentration that is typical of milk.
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Knoche, Moritz, Peter D. Petracek, Martin J. Bukovac, and Warren E. Shafer. "Urea Penetration of Isolated Tomato Fruit Cuticles." Journal of the American Society for Horticultural Science 119, no. 4 (July 1994): 761–64. http://dx.doi.org/10.21273/jashs.119.4.761.
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14C-urea penetration of isolated tomato (Lycopersicon esculentum Mill. cv. `Pik Red') fruit cuticular membranes (CM) was studied as a function of concentration and temperature. There was no significant effect of cuticular wax on urea penetration at 25C, permeances for the CM being 8.4 × 10-10 and dewaxed CM (DCM) 11.1 × 10-10·m·s-1. Time lags were near zero for both CM and DCM. Steady-state diffusion analysis suggests that the relatively low cuticular permeance of urea is due to low partitioning that offsets high diffusivity. Urea flux through the CM and DCM showed ≈1.5- and 1.9-fold increases, respectively, for each 10C increase between 5 and 45C. Urea flux across CM and DCM increased linearly with concentration (10 μm to 1 m) and, thus, was a first-order process.
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Ahmad, Mohd Azwan, Bidattul Syirat Zainal, Nashrah Hani Jamadon, Thomas Choong Shean Yaw, and Luqman Chuah Abdullah. "Filtration analysis and fouling mechanisms of PVDF membrane for POME treatment." Journal of Water Reuse and Desalination 10, no. 3 (June 29, 2020): 187–99. http://dx.doi.org/10.2166/wrd.2020.101.
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Abstract Palm oil mill effluent (POME) is a hazardous wastewater which contains high organic constituents and salt concentrations. The ultrafiltration (UF) process is a promising treatment design used for secondary treatment such as POME. However, membrane fouling is the major problem which limits the performance of the UF. This paper describes a detailed investigation of polyvinylidiene fluoride (PVDF) membrane for the treatment of POME. The fouling behavior was analyzed by water flux, fouling mechanism, scanning electron microscopy (SEM), particle size distribution (PSD) and Energy Dispersive X-ray (EDX). It was found that a significant reduction in the permeate flux was caused by the build up of a fouling layer. Study on the fouling mechanism shows that cake filtration dominated the fouling activities on the membrane surface, compared to standard blocking, intermediate blocking, and complete blocking. This result is supported by membrane autopsy through SEM, PSD and EDX.
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Heidebrecht, Hans-Jürgen, José Toro-Sierra, and Ulrich Kulozik. "Concentration of Immunoglobulins in Microfiltration Permeates of Skim Milk: Impact of Transmembrane Pressure and Temperature on the IgG Transmission Using Different Ceramic Membrane Types and Pore Sizes." Foods 7, no. 7 (June 28, 2018): 101. http://dx.doi.org/10.3390/foods7070101.
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Wang, Qian, and Bruce D. Schultz. "Cholera toxin enhances Na+absorption across MCF10A human mammary epithelia." American Journal of Physiology-Cell Physiology 306, no. 5 (March 1, 2014): C471—C484. http://dx.doi.org/10.1152/ajpcell.00181.2013.
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Cellular mechanisms to account for the low Na+concentration in human milk are poorly defined. MCF10A cells, which were derived from human mammary epithelium and grown on permeable supports, exhibit amiloride- and benzamil-sensitive short-circuit current ( Isc; a sensitive indicator of net ion transport), suggesting activity of the epithelial Na+channel ENaC. When cultured in the presence of cholera toxin (Ctx), MCF10A cells exhibit greater amiloride-sensitive Iscat all time points tested (2 h to 7 days), an effect that is not reduced with Ctx washout for 12 h. Amiloride-sensitive Iscremains elevated by Ctx in the presence of inhibitors for PKA (H-89, Rp-cAMP), PI3K (LY294002), and protein trafficking (brefeldin A). Additionally, the Ctx B subunit, alone, does not replicate these effects. RT-PCR and Western blot analyses indicate no significant increase in either the mRNA or protein expression for α-, β-, or, γ-ENaC subunits. Ctx increases the abundance of both β- and γ-ENaC in the apical membrane. Additionally, Ctx increases both phosphorylated and nonphosphorylated Nedd4-2 expression. These results demonstrate that human mammary epithelia express ENaC, which can account for the low Na+concentration in milk. Importantly, the results suggest that Ctx increases the expression but reduces the activity of the E3 ubiquitin ligase Nedd4-2, which would tend to reduce the ENaC retrieval and increase steady-state membrane residency. The results reveal a novel mechanism in human mammary gland epithelia by which Ctx regulates ENaC-mediated Na+transport, which may have inferences for epithelial ion transport regulation in other tissues throughout the body.
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Boman, B., M. Ek, W. Heyman, and B. Frostell. "Membrane Filtration Combined with Biological Treatment for Purification of Bleach Plant Effluents." Water Science and Technology 24, no. 3-4 (August 1, 1991): 219–28. http://dx.doi.org/10.2166/wst.1991.0478.
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A bleach plant effluent from softwood kraft pulping was treated in the laboratory with a combination of ultrafiltration and different biological methods. The E-stage effluent was firstly membrane filtered using membranes with a nominal cut-off of 8,000 Dalton. In the filtration, a concentration factor of 15 was used at 55°C. The treatment resulted in 89% AOX removal and 87% COD removal. Calculated in relation to the actual flows of E-stage and (C+D)-stage effluent at the mill, this corresponded to AOX and COD removals of 20% and 41% respectively. Before the biological treatment, the permeate was mixed with (C+D)-stage effluent and treated in three parallel biological systems, an aerated lagoon with and without solids recycle, an airlift system with a mixed fungal flora and an anaerobic filter. For the lagoon treatment, a hydraulic retention time of 7 days was used at biomass concentrations of 70, 350 and 480 mg TSS/l and 20-22°C. The fungal system was evaluated at retention times of 5.5 11 and 22 h, 770 mg TSS/l and 37°C. For the anaerobic filter, retention times of 1, 5 and 25 h at a temperature of 35°C were used. Very promising results were obtained with the combination of physical and biological treatment. The aerated lagoon with solids recycle gave the best results with 66% of AOX, 72% of COD and 95% of the BOD being removed in the combined process. The anaerobic filter also gave good results, but in practice a small aerobic post-treatment would probably be necessary. The three systems were also evaluated for the removal of chlorinated phenolic compounds and acute toxicity according to the Microtox test. The results suggest that a combination of membrane filtration and anaerobic/aerobic or just aerobic treatment would be an attractive way to handle kraft mill bleach plant effluents.
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Alique, David, Giacomo Bruni, Raúl Sanz, José Antonio Calles, and Silvano Tosti. "Ultra-Pure Hydrogen via Co-Valorization of Olive Mill Wastewater and Bioethanol in Pd-Membrane Reactors." Processes 8, no. 2 (February 13, 2020): 219. http://dx.doi.org/10.3390/pr8020219.
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Olive mill wastewater (OMW) presents high environmental impact due to the fact of its elevated organic load and toxicity, especially in Mediterranean countries. Its valorization for simultaneous pollutants degradation and green energy production is receiving great attention, mainly via steam reforming for hydrogen generation. Following previous works, the present research goes into detail about OMW valorization, particularly investigating for the first time the potential benefits of OMW–bioethanol mixtures co-reforming for ultra-pure hydrogen production in Pd-membrane reactors. In this manner, the typical large dilution of OMW and, hence, excess water can be used as a reactant for obtaining additional hydrogen from ethanol. Fresh OMW was previously conditioned by filtration and distillation processes, analyzing later the effect of pressure (1–5 bar), oxidizing conditions (N2 or air as carrier gas), gas hourly space velocity (150–1500 h−1), and alcohol concentration on the co-reforming process (5–10% v/v). In all cases, the exploitation of OMW as a source of environmentally friendly hydrogen was demonstrated, obtaining up to 30 NmL·min−1 of pure H2 at the most favorable experimental conditions. In the membrane reactor, higher pressures up to 5 bar promoted both total H2 production and pure H2 recovery due to the increase in the permeate flux despite the negative effect on reforming thermodynamics. The increase of ethanol concentration also provoked a positive effect, although not in a proportional relation. Thus, a greater effect was obtained for the increase from 5% to 7.5% v/v in comparison to the additional improvement up to 10% v/v. On the contrary, the use of oxidative conditions slightly decreased the hydrogen production rate, while the effect of gas hourly space velocity needs to be carefully analyzed due to the contrary effect on potential total H2 generation and pure H2 recovery.
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Dzyazko, Yuliya, Vladimir Zakharov, Yevhen Kolomiiets, and Kateryna Kudelko. "COMPOSITE ION-EXCHANGES FOR THE RECYCLING OF LIQUID WASTE OF DAIRY INDUSTRY." Ukrainian Chemistry Journal 86, no. 5 (July 15, 2020): 38–52. http://dx.doi.org/10.33609/2708-129x.86.5.2020.38-52.
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The method of directed formation of particles of hydrated zirconium and titanium oxides into anion exchange resins has been developed. The approach based on the Ostwald-Freundlich thermodynamic equation is applied. Such approach, in particular, connects the size of particles with the solubility of the compound, volume and concentration of reagents. Less soluble zirconium dioxide is deposited as non-aggregated nanoparticles, the size of which does not exceed 10 nm. The composition of such composites is the most reproducible. In the case of more soluble titanium dioxide, aggregates of nanoparticles (up to 70 nm) are formed. When the concentration of the solution of metal salts in the polymer increases, the particles of micron size are deposited, the composition of this type of material is less reproduced. Non-aggregated nanoparticles increase the exchange capacity of the polymer. This leads to an increase in its electrical conductivity in 1.4-1.8 times. This is due to an increase in the concentration of mobile charge carriers in the polymer matrix that is caused by reducing its swelling. Other reason is a contribution of the counter-ions of the functional groups of inorganic component to ion transport. On the contrary, the aggregates of nanoparticles amplify the polymer swelling, resulting in a reduction of exchange capacity and electrical conductivity. Ion-exchangers were used for the ion exchange processing of nanofiltration permeate of milky whey, and for electromembrane desalination of protein concentrate.
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Ghazali, Nazlee Faisal, and Lim Ki Min. "Mass Transport Models in Organic Solvent Nanofiltration: A Review." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 76, no. 3 (October 29, 2020): 126–38. http://dx.doi.org/10.37934/arfmts.76.3.126138.
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Membrane technology has been gradually used as an alternative to the conventional separation and purification method in various industries. In recent years, solvent-stable nanofiltration or organic solvent nanofiltration has becoming practicable through the development of solvent-stable commercial polymeric membranes. Organic solvent nanofiltration has a great potential to replace the conventional energy-demanding process such as distillation due to its ability of separating organic solvents and solutes on a molecular level without phase change and operation at relatively mild temperature. Predicting the performance of such membrane separations is crucial in the process design. Important performance indicator such as the permeate flux and the rejections are strongly related to the fluid dynamics, mass transfer and solute-solvent-membrane interactions. The aim of this paper is to review and assess the transport models of solute and solvent transport relevant to organic solvent nanofiltration. The link between concentration polarization and the hydrodynamics in various configurations are discussed. The effects of process variables on membrane performance and solute-solvent membrane interactions are also reviewed.
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Ross, W. R., J. P. Barnard, N. K. H. Strohwald, C. J. Grobler, and J. Sanetra. "Practical Application of the ADUF Process to the Full-Scale Treatment of a Maize-Processing Effluent." Water Science and Technology 25, no. 10 (May 1, 1992): 27–39. http://dx.doi.org/10.2166/wst.1992.0235.
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ADUFR (anaerobic digestion ultrafiltration) is a membrane-assisted process for positive separation of biomass from the treated effluent. Pilot and full-scale ADUFR studies were carried out on a maize-processing effluent (15 kgCOD/m3) at the Meyerton mill of Messrs. African Products, South Africa. The results after 15 months of full-scale operation have illustrated the merits of the process for the production of a colloid-free effluent at a mean COD removal efficiency of 97%. The permeate flux varied in the range 37 to 8 l.m−2.h−1 at 35°C, inlet pressure of 450 kPa, linear tube velocity of 1.6 m/s and digester suspended solids concentration of 21 kg/m3. Periodic chemical cleaning of the unsupported tubular polyethersulphone membranes with EDTA was only commenced after 13 months operation. A mean plant space load rate of 3 kgCOD.m−3.d−1 guaranteed reliability to withstand high COD shock loadings due to variations in the feed load. Bio-membrane separation technology of this nature holds important economic advantages for the treatment of a wide spectrum of organic industrial effluents.
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Quesnell, Rebecca R., Jamie Erickson, and Bruce D. Schultz. "Apical electrolyte concentration modulates barrier function and tight junction protein localization in bovine mammary epithelium." American Journal of Physiology-Cell Physiology 292, no. 1 (January 2007): C305—C318. http://dx.doi.org/10.1152/ajpcell.00567.2005.
Full textAbstract:
In vitro mammary epithelial cell models typically fail to form a consistently tight barrier that can effectively separate blood from milk. Our hypothesis was that mammary epithelial barrier function would be affected by changes in luminal ion concentration and inflammatory cytokines. Bovine mammary epithelial (BME-UV cell line) cells were grown to confluence on permeable supports with a standard basolateral medium and either high-electrolyte (H-elec) or low-electrolyte (L-elec) apical medium for 14 days. Apical media were changed to/from H-elec medium at predetermined times prior to assay. Transepithelial electrical resistance ( Rte) was highest in monolayers continuously exposed to apical L-elec. A time-dependent decline in Rte began within 24 h of H-elec medium exposure. Change from H-elec medium to L-elec medium time-dependently increased Rte. Permeation by FITC-conjugated dextran was elevated across monolayers exposed to H-elec, suggesting compromise of a paracellular pathway. Significant alteration in occludin distribution was evident, concomitant with the changes in Rte, although total occludin was unchanged. Neither substitution of Na+ with N-methyl-d-glucosamine (NMDG+) nor pharmacological inhibition of transcellular Na+ transport pathways abrogated the effects of apical H-elec medium on Rte. Tumor necrosis factor alpha, but not interleukin-1β nor interleukin-6, in the apical compartment caused a significant decrease in Rte within 8 h. These results indicate that mammary epithelium is a dynamic barrier whose cell-cell contacts are acutely modulated by cytokines and luminal electrolyte environment. Results not only demonstrate that BME-UV cells are a model system representative of mammary epithelium but also provide critical information that can be applied to other mammary model systems to improve their physiological relevance.