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M A Drake - One of the best experts on this subject based on the ideXlab platform.
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short communication the influence of solids concentration and Bleaching Agent on Bleaching efficacy and flavor of sweet whey powder
Journal of Dairy Science, 2015Co-Authors: M G Jervis, T J Smith, M A DrakeAbstract:Abstract Recent studies have demonstrated the effect of Bleaching conditions and Bleaching Agent on flavor and functional properties of whey protein ingredients. Solids concentration at Bleaching significantly affected Bleaching efficacy and flavor effects of different Bleaching Agents. It is not known if these parameters influence quality of sweet whey powder (SWP). The purpose of this study was to determine the effects of solids concentration and Bleaching Agent on the flavor and Bleaching efficacy of SWP. Colored cheddar whey was manufactured, fat separated, and pasteurized. Subsequently, the whey (6.7% solids) was bleached, concentrated using reverse osmosis (RO) to 14% solids, and then spray dried, or whey was concentrated before Bleaching and then spray dried. Bleaching treatments included a control (no Bleaching, 50°C, 60 min), hydrogen peroxide (HP; 250 mg/kg, 50°C, 60 min), benzoyl peroxide (50 mg/kg, 50°C, 60 min), lactoperoxidase (20 mg/kg of HP, 50°C, 30 min), and external peroxidase (MaxiBright, DSM Food Specialties, Delft, the Netherlands; 2 dairy Bleaching units/mL, 50°C, 30 min). The experiment was repeated in triplicate. Sensory properties and volatile compounds of SWP were evaluated by a trained panel and gas chromatography-mass spectrometry, respectively. Bleaching efficacy (norbixin destruction) and benzoic acid were measured by HPLC. Differences in Bleaching efficacy, sensory and volatile compound profiles, and benzoic acid were observed with different Bleaching Agents, consistent with previous studies. Solids concentration affected Bleaching efficacy of HP, but not other Bleaching Agents. The SWP from whey bleached with HP or lactoperoxidase following RO had increased cardboard and fatty flavors and higher concentrations of lipid oxidation compounds compared with SWP from whey bleached before RO. The SWP bleached with benzoyl peroxide after RO contained less benzoic acid than SWP from whey bleached before RO. These results indicate that solids concentration at Bleaching and Bleaching Agent affect quality of SWP.
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the influence of Bleaching Agent and temperature on Bleaching efficacy and volatile components of fluid whey and whey retentate
Journal of Food Science, 2013Co-Authors: T J Smith, Patrick D Gerard, M A DrakeAbstract:Fluid whey or retentate are often bleached to remove residual annatto Cheddar cheese colorant, and this process causes off-flavors in dried whey proteins. This study determined the impact of temperature and Bleaching Agent on Bleaching efficacy and volatile components in fluid whey and fluid whey retentate. Freshly manufactured liquid whey (6.7% solids) or concentrated whey protein (retentate) (12% solids, 80% protein) were bleached using benzoyl peroxide (BP) at 100 mg/kg (w/w) or hydrogen peroxide (HP) at 250 mg/kg (w/w) at 5 °C for 16 h or 50 °CC for 1 h. Unbleached controls were subjected to a similar temperature profile. The experiment was replicated three times. Annatto destruction (Bleaching efficacy) among treatments was compared, and volatile compounds were extracted and separated using solid phase microextraction gas chromatography mass spectrometry (SPME GC-MS). Bleaching efficacy of BP was higher than HP (P 0.05). Retentate bleached with HP at either temperature had higher relative abundances of pentanal, hexanal, heptanal, and octanal than BP bleached retentate (P < 0.05). Liquid wheys generally had lower concentrations of selected volatiles compared to retentates. These results suggest that the highest Bleaching efficacy (within the parameters evaluated) in liquid whey is achieved using BP at 5 or 50 °C and at 50 °C with HP or BP in whey protein retentate. Practical Application Benzoyl peroxide and hydrogen peroxide are the two chemical Bleaching Agents approved for Bleaching whey in the United States. Previous studies have shown less norbixin destruction and increased off-flavor production using HP compared to BP in liquid whey. No published studies have compared Bleaching parameters of liquid whey and whey retentate. BP is an effective Bleaching Agent in fluid whey or retentate at 5 or 50 °C. In contrast, optimal Bleaching with HP occurs in whey protein retentate (12% solids, 80% protein). Decreased production of lipid oxidation volatiles occurred at 5 °C compared to 50 °C with HP Bleaching and suggests that HP Bleaching in whey protein retentate should occur at colder temperatures (5 °C).
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effect of temperature and Bleaching Agent on Bleaching of liquid cheddar whey
Journal of Dairy Science, 2012Co-Authors: M A D Listiyani, R E Campbell, R E Miracle, D M Barbano, Patrick D Gerard, M A DrakeAbstract:Abstract The use of whey protein as an ingredient in foods and beverages is increasing, and thus demand for colorless and mild-tasting whey protein is rising. Bleaching is commonly applied to fluid colored cheese whey to decrease color, and different temperatures and bleach concentrations are used. The objectives of this study were to compare the effects of hot and cold Bleaching, the point of Bleaching (before or after fat separation), and Bleaching Agent on Bleaching efficacy and volatile components of liquid colored and uncolored Cheddar whey. First, Cheddar whey was manufactured, pasteurized, fat-separated, and subjected to one of a number of hot (68°C) or cold (4°C) Bleaching applications [hydrogen peroxide (HP) 50 to 500mg/kg; benzoyl peroxide (BP) 25 to 100mg/kg] followed by measurement of residual norbixin and color by reflectance. Bleaching Agent concentrations were then selected for the second trial. Liquid colored Cheddar whey was manufactured in triplicate and pasteurized. Part of the whey was collected (no separation, NSE) and the rest was subjected to fat separation (FSE). The NSE and FSE wheys were then subdivided and Bleaching treatments (BP 50 or 100mg/kg and HP 250 or 500mg/kg) at 68°C for 30min or 4°C for 16h were applied. Control NSE and FSE with no added bleach were also subjected to each time–temperature combination. Volatile compounds from wheys were evaluated by gas chromatography-mass spectrometry, and norbixin (annatto) was extracted and quantified to compare Bleaching efficacy. Proximate analysis, including total solids, protein, and fat contents, was also conducted. Liquid whey subjected to hot Bleaching at both concentrations of HP or at 100mg/kg BP had greater lipid oxidation products (aldehydes) compared with unbleached wheys, 50mg/kg BP hot-bleached whey, or cold-bleached wheys. No effect was detected between NSE and FSE liquid Cheddar whey on the relative abundance of volatile lipid oxidation products. Wheys bleached with BP had lower norbixin content compared with wheys bleached with HP. Bleaching efficacy of HP was decreased at 4°C compared with 68°C, whereas that of BP was not affected by temperature. These results suggest that fat separation of liquid Cheddar whey has no effect on Bleaching efficacy or lipid oxidation and that hot Bleaching may result in increased lipid oxidation in fluid whey.
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the effect of Bleaching Agent on the flavor of liquid whey and whey protein concentrate
Journal of Dairy Science, 2009Co-Authors: A E Croissant, R E Campbell, E J Kang, E Bastian, M A DrakeAbstract:Abstract The increasing use and demand for whey protein as an ingredient requires a bland-tasting, neutral-colored final product. The Bleaching of colored Cheddar whey is necessary to achieve this goal. Currently, hydrogen peroxide (HP) and benzoyl peroxide (BPO) are utilized for Bleaching liquid whey before spray drying. There is no current information on the effect of the Bleaching process on the flavor of spray-dried whey protein concentrate (WPC). The objective of this study was to characterize the effect of Bleaching on the flavor of liquid and spray-dried Cheddar whey. Cheddar cheeses colored with water-soluble annatto were manufactured in duplicate. Four Bleaching treatments (HP, 250 and 500mg/kg and BPO, 10 and 20mg/kg) were applied to liquid whey for 1.5h at 60°C followed by cooling to 5°C. A control whey with no bleach was also evaluated. Flavor of the liquid wheys was evaluated by sensory and instrumental volatile analysis. One HP treatment and one BPO treatment were subsequently selected and incorporated into liquid whey along with an unbleached control that was processed into spray-dried WPC. These trials were conducted in triplicate. The WPC were evaluated by sensory and instrumental analyses as well as color and proximate analyses. The HP-bleached liquid whey and WPC contained higher concentrations of oxidation reaction products, including the compounds heptanal, hexanal, octanal, and nonanal, compared with unbleached or BPO-bleached liquid whey or WPC. The HP products were higher in overall oxidation products compared with BPO samples. The HP liquid whey and WPC were higher in fatty and cardboard flavors compared with the control or BPO samples. Hunter CIE Lab color values (L*, a*, b*) of WPC powders were distinct on all 3 color scale parameters, with HP-bleached WPC having the highest L* values. Hydrogen peroxide resulted in a whiter WPC and higher off-flavor intensities; however, there was no difference in norbixin recovery between HP and BPO. These results indicate that the Bleaching of liquid whey may affect the flavor of WPC and that the type of Bleaching Agent used may affect WPC flavor.
Luiz Andre Freire Pimenta - One of the best experts on this subject based on the ideXlab platform.
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microhardness evaluation of in situ vital Bleaching on human dental enamel using a novel study design
Dental Materials, 2005Co-Authors: José Augusto Rodrigues, Harald O Heymann, Luiz Andre Freire Pimenta, Giselle Maria Marchi, Glaucia Maria Bovi AmbrosanoAbstract:Summary Objectives The aim of this ‘in situ’ study was to evaluate the microhardness of dental enamel following treatment with an in-office and an at-home vital Bleaching Agent through a novel approach using samples temporarily bonded ‘in vivo’. Methods Human dental enamel slabs ( n =88) were subjected to sequential polishing and initial Knoop microhardness tests were performed. The slabs were fixed to the facial surfaces of the maxillary first molars of 44 human volunteers. They were divided into four groups ( n =11) according to the treatment group: G1- in-office-CP37+ at-home-CP10; G2- in-office-CP37+ at-home-PLA; G3- in-office-PLA and at-home-CP10; G4- in-office and at-home-PLA. After 3 weeks of treatment, final microhardness measurements were performed. Results and Significance ANOVA and Tukey's HSD hoc analysis ( α =0.05) revealed no differences among initial or final microhardness values ( p >0.05); however, significant differences occurred between initial and final values for each group ( p
Purificación Varela-patiño - One of the best experts on this subject based on the ideXlab platform.
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Colorimeter and Scanning Electron Microscopy Analysis of Teeth Submitted to Internal Bleaching
Journal of Endodontics, 2010Co-Authors: Benjamín Martín-biedma, Teresa Gonzalez-gonzalez, José Bahillo, Ruth Vilar, Manuela Lopes, Luís Lopes, Purificación Varela-patiñoAbstract:Introduction: This in vitro study compared the tooth color and the ultrastructure of internal dental tissues before and after internal Bleaching. Methods: Sodium perborate was placed in the pulp chamber of endodontically treated molars and sealed with intermediate restorative material. The test samples were stored in a physiologic solution, and the Bleaching Agent was replaced every 7 days. A control group was used. After 1 month, the colors of the test and control samples were measured with a colorimeter, and the internal surfaces were observed under field emission scanning electron microscopy (FESEM). Results: Statistically significant differences were found between the test and control sample colors. The FESEM ultrastructure analysis of the internal enamel and dentin surfaces did not show any changes after the internal Bleaching. Conclusions: The results of the present study show that sodium perborate is effective in Bleaching nonvital teeth and does not produce ultrastructural changes in the dental tissues. © 2010 American Association of Endodontists.
Giselle Maria Marchi - One of the best experts on this subject based on the ideXlab platform.
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Effect of low-level laser therapy on odontoblast-like cells exposed to Bleaching Agent
Lasers in Medical Science, 2014Co-Authors: Adriano Fonseca Lima, Giselle Maria Marchi, Ana Paula Dias Ribeiro, Fernanda Gonçalves Basso, Vanderlei Salvador Bagnato, Josimeri Hebling, Carlos Alberto Souza CostaAbstract:The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like MDPC-23 cells exposed to carbamide peroxide (CP 0.01 %–2.21 μg/mL of H_2O_2). The cells were seeded in sterile 24-well plates for 72 h. Eight groups were established according to the exposure or not to the Bleaching Agents and the laser energy doses tested (0, 4, 10, and 15 J/cm^2). After exposing the cells to 0.01 % CP for 1 h, this Bleaching solution was replaced by fresh culture medium. The cells were then irradiated (three sections) with a near-infrared diode laser (InGaAsP—780 ± 3 nm, 40 mW), with intervals of 24 h. The 0.01 % CP solution caused statistically significant reductions in cell metabolism and alkaline phosphate (ALP) activity when compared with those of the groups not exposed to the Bleaching Agent. The LLLT did not modulate cell metabolism; however, the dose of 4 J/cm^2 increased the ALP activity. It was concluded that 0.01 % CP reduces the MDPC-23 cell metabolism and ALP activity. The LLLT in the parameters tested did not influence the cell metabolism of the cultured cells; nevertheless, the laser dose of 4 J/cm^2 increases the ALP activity in groups both with and without exposure to the Bleaching Agent.
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Effects of Laser Irradiation on Pulp Cells Exposed to Bleaching Agents.
Photochemistry and Photobiology, 2013Co-Authors: Adriano Fonseca Lima, Giselle Maria Marchi, Ana Paula Dias Ribeiro, Fernanda Gonçalves Basso, Vanderlei Salvador Bagnato, Josimeri Hebling, Carlos Alberto Souza CostaAbstract:The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like cells exposed to a Bleaching Agent. Mouse dental papilla cell-23 cells were seeded in wells of 24-well plates. Eight groups were established according to the exposure to the Bleaching Agent and LLLT (0, 4, 10 and 15 J cm 2 ). Enamel–dentin disks were adapted to artificial pulp chambers, which were individually placed in wells containing Dulbecco’s modified Eagle’s medium (DMEM). A Bleaching Agent (35% hydrogen peroxide [BA35%HP]) was applied on enamel (15 min) to obtain the extracts (DMEM + BA35%HP components diffused through enamel/dentin disks). The extracts were applied (1 h) to the cells, and then subjected to LLLT. Cell viability (Methyl tetrazolium assay), alkaline phosphatase (ALP) activity, as well as gene expression of ALP, fibronectin (FN) and type I collagen, were evaluated. The Bleaching procedures reduced the cell viability, ALP activity and gene expression of dentin proteins. Laser irradiation did not modulate the cell response; except for FN, as LLLT decreased the gene expression of this protein by the cells exposed to the BA35%HP. It can be concluded that BA35%HP decreased the activities of odontoblasts that were not recovered by the irradiation of the damaged cells with low-level laser parameters tested.
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protective effect of sodium ascorbate on mdpc 23 odontoblast like cells exposed to a Bleaching Agent
European Journal of Dentistry, 2010Co-Authors: Adriano Fonseca Lima, Josimeri Hebling, F C Lessa, De Souza Costa Ca, Giselle Maria MarchiAbstract:OBJECTIVES: To evaluate the cytotoxic effects of a Bleaching Agent composed of 0.01% carbamide peroxide (CP; 2.21mug/ml H(2)O(2)) on the MDPC-23 odontoblastic cell line, and to determine whether sodium ascorbate (SA) is capable of reducing, or even eliminating, the toxic effects caused by this Bleaching Agent. METHODS: The cells were seeded in wells and incubated for 48 hours. CP and SA were dissolved in a culture medium (DMEM) in order to obtain experimental extracts. Six groups of cells (n=10) were treated as follows: G1: no treatment (control); G2: 0.25 mM SA/60 min; G3: 0.5 mM SA/60 min; G4: 0.25 mM SA+0.01% CP/60 min; G5: 0.5 mM SA+0.01% CP/60 min; and G6: 0.01% CP/60 min. The cell metabolism was evaluated by MTT assay, and the cell morphology was assessed by scanning electron microscopy. The data obtained were analyzed by 2-way ANOVA and post-hoc Tukey's test (alpha=5%). RESULTS: THE PERCENTAGES OF CELL METABOLISM WERE AS FOLLOWS: G1 (control)=100%; G2=110.06%, G3=108.57%, G4=90.35%, G5=97.63%, and G6=66.88%. Group 6 presented a statistically lower cell metabolism than did the other groups, and the cells that remained on the substrate exhibited changes in their morphology. SA decreased the cytotoxic effects caused by CP, demonstrating its protective effect against the toxic components of this dental product. CONCLUSIONS: It was concluded that CP gel has cytopathic effects on MDPC-23 odontoblastic cells, even at low concentrations such as 0.01%. SA at 0.25 mM, and that 0.5 mM is able to protect these cultured cells against the cytotoxic effects of CP.
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microhardness evaluation of in situ vital Bleaching on human dental enamel using a novel study design
Dental Materials, 2005Co-Authors: José Augusto Rodrigues, Harald O Heymann, Luiz Andre Freire Pimenta, Giselle Maria Marchi, Glaucia Maria Bovi AmbrosanoAbstract:Summary Objectives The aim of this ‘in situ’ study was to evaluate the microhardness of dental enamel following treatment with an in-office and an at-home vital Bleaching Agent through a novel approach using samples temporarily bonded ‘in vivo’. Methods Human dental enamel slabs ( n =88) were subjected to sequential polishing and initial Knoop microhardness tests were performed. The slabs were fixed to the facial surfaces of the maxillary first molars of 44 human volunteers. They were divided into four groups ( n =11) according to the treatment group: G1- in-office-CP37+ at-home-CP10; G2- in-office-CP37+ at-home-PLA; G3- in-office-PLA and at-home-CP10; G4- in-office and at-home-PLA. After 3 weeks of treatment, final microhardness measurements were performed. Results and Significance ANOVA and Tukey's HSD hoc analysis ( α =0.05) revealed no differences among initial or final microhardness values ( p >0.05); however, significant differences occurred between initial and final values for each group ( p
José Augusto Rodrigues - One of the best experts on this subject based on the ideXlab platform.
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Microhardness and color monitoring of nanofilled resin composite after Bleaching and staining
European Journal of Dentistry, 2014Co-Authors: Isabel Cristina G Bandeira De Andrade, Flávia Lucisano Botelho Amaral, José Augusto Rodrigues, Roberta Tarkany Basting, Cecilia Pedroso Turssi, Felipe Maia Galvão FrançaAbstract:OBJECTIVES: The present study aimed to investigate the effect of staining solutions on microhardness and shade changes of a nanofilled resin composite, which had been previously in contact with Bleaching Agents.\n\nMATERIALS AND METHODS: A total of 135 disk-shaped specimens (10 mm × 2 mm) were fabricated with a nanofilled resin (Filtek Supreme) and photocured with a Light Emission Diode (LED) unit and then allocated into three groups to be bleached with 10% or 16% carbamide peroxide (CP) Bleaching Agents or a 35% hydrogen peroxide (HP) product. Following Bleaching, specimens within each group were subdivided into three groups to be immersed in coffee, red wine or distilled water. Microhardness and color were monitored at baseline, after Bleaching and after staining.\n\nRESULTS: Analysis of variance for split-plot design showed lower microhardness values when the composite had been in contact with HP (P < 0.0001). The specimens immersed in red wine and coffee provided lower microhardness values than those immersed in distilled water, regardless of the Bleaching Agent to which the composites were previously exposed. Kruskal Wallis and Dunn tests demonstrated that the composite was lighter after Bleaching with a 35% HP Agent (P < 0.0500).\n\nCONCLUSION: The composite was darker as a result of being immersed either in red wine or coffee, regardless of the Bleaching Agent.
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microhardness evaluation of in situ vital Bleaching on human dental enamel using a novel study design
Dental Materials, 2005Co-Authors: José Augusto Rodrigues, Harald O Heymann, Luiz Andre Freire Pimenta, Giselle Maria Marchi, Glaucia Maria Bovi AmbrosanoAbstract:Summary Objectives The aim of this ‘in situ’ study was to evaluate the microhardness of dental enamel following treatment with an in-office and an at-home vital Bleaching Agent through a novel approach using samples temporarily bonded ‘in vivo’. Methods Human dental enamel slabs ( n =88) were subjected to sequential polishing and initial Knoop microhardness tests were performed. The slabs were fixed to the facial surfaces of the maxillary first molars of 44 human volunteers. They were divided into four groups ( n =11) according to the treatment group: G1- in-office-CP37+ at-home-CP10; G2- in-office-CP37+ at-home-PLA; G3- in-office-PLA and at-home-CP10; G4- in-office and at-home-PLA. After 3 weeks of treatment, final microhardness measurements were performed. Results and Significance ANOVA and Tukey's HSD hoc analysis ( α =0.05) revealed no differences among initial or final microhardness values ( p >0.05); however, significant differences occurred between initial and final values for each group ( p
