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David Julian Mcclements - One of the best experts on this subject based on the ideXlab platform.

  • oil in water pickering emulsions via Microfluidization with cellulose nanocrystals 1 formation and stability
    Food Hydrocolloids, 2019
    Co-Authors: Shanshan Lv, David Julian Mcclements, Wenchao Xiang, Siqi Huan, Orlando J Rojas
    Abstract:

    Abstract Oil-in-water Pickering emulsions were successfully prepared via high-energy Microfluidization using cellulose nanocrystals (CNC) as interfacial stabilizers. The influence of Microfluidization pressure, CNC concentration, and oil type on droplet size and emulsion stability was determined. Under optimized homogenization conditions, CNC formed and stabilized emulsions based on corn, fish, sunflower, flax, orange, and MCT oils. The droplet size decreased with increasing Microfluidization pressure from 9 to 17 kpsi, but then increased slightly at 19 kpsi. The creaming stability of the emulsions increased with CNC concentration, which was mainly attributed to the decrease in droplet size (mean particle diameter  ≤ 100 mM; temperature from 30 to 90 °C. Droplet flocculation was, however, observed under more acidic conditions (pH 2) and at high ionic strength (200–500 mM NaCl), owing to electrostatic screening. Our results indicate that Microfluidization is an effective method for forming CNC-stabilized Pickering emulsions suitable for utilization in the food industry.

  • Modulation of physical properties of microfluidized whey protein fibrils with chitosan.
    Food Research International, 2018
    Co-Authors: Cheryl Chung, Rachael A. Picard, Thaddao Ogren, William Mutilangi, David Julian Mcclements
    Abstract:

    Abstract There is an increasing market for food and beverage products enriched in proteins and dietary fibers due to their potential health benefits. In this study, the effect of heating (85 °C, 20 min), Microfluidization (20,000 psi), and pH (2 to 6.5) on the physicochemical properties of aqueous solutions containing mixtures of whey protein fibrils (7.5%; WPF) and chitosan (0.5%; CN) were examined. Heating of the mixed systems increased their turbidity and apparent viscosity, which was attributed to the formation of protein-rich particles. Interestingly, heating the mixed systems and then applying Microfluidization led to phase separation and a lower apparent viscosity, which was attributed to high-pressure disruption of the whey protein fibrils. The pH of the systems significantly influenced their appearance, turbidity, particle size, and apparent viscosity, with high turbidity and viscosity, and large particle size occurring from pH 3.5 to 5.5. These effects were attributed to protein aggregation close to its isoelectric point (pH 5) coupled with electrostatic attraction between anionic groups on the whey protein and cationic groups on the chitosan. The addition of chitosan increased the net isoelectric point from pH 5 for pure whey protein to pH 6 for the mixed system. Overall, this study showed that the appearance and rheological properties of protein-dietary fiber mixtures could be manipulated by heating, Microfluidization, and pH adjustment. This information may be useful for designing protein and fiber enriched food and beverage products with desirable physical and sensory properties.

  • fabrication of oil in water nanoemulsions by dual channel Microfluidization using natural emulsifiers saponins phospholipids proteins and polysaccharides
    Food Hydrocolloids, 2016
    Co-Authors: Siqi Huan, David Julian Mcclements, Jiyou Gu
    Abstract:

    Nanoemulsions are utilized within the food, pharmaceutical, and personal care industries because of their unique physicochemical properties and functional attributes: high optical clarity; prolonged stability; and, enhanced bioavailability. For many applications, it is desirable to utilize natural ingredients to formulate nanoemulsions so as to create “label-friendly” products. In this study, we compared the effectiveness of a number of natural emulsifiers at fabricating corn oil-in-water nanoemulsions using dual-channel Microfluidization. These emulsifiers were either amphiphilic biopolymers (whey protein and gum arabic) or biosurfactants (quillaja saponin and soy lecithin). Differences in the surface activities of these emulsifiers were characterized using interfacial tension measurements. The influence of emulsifier type, concentration, and homogenization pressure on the efficiency of nanoemulsion formation was examined. The long-term stability of the fabricated nanoemulsions was also monitored during storage at ambient temperature. For all of the natural emulsifiers, nanoemulsions could be produced by dual-channel Microfluidization, with the mean particle diameter decreasing with increasing emulsifier concentration and homogenization pressure. Whey protein isolate and quillaja saponin were more effective at forming nanoemulsions containing fine droplets than gum arabic and soy lecithin, with a lower amount of emulsifier required and smaller droplets being produced. This effect was attributed to faster emulsifier adsorption and a greater reduction in interfacial tension leading to more efficient droplet disruption within the homogenizer for saponins and whey proteins. This study highlights the potential of dual-channel Microfluidization for efficiently producing label-friendly nanoemulsions from natural emulsifiers.

  • development of Microfluidization methods for efficient production of concentrated nanoemulsions comparison of single and dual channel microfluidizers
    Journal of Colloid and Interface Science, 2016
    Co-Authors: David Julian Mcclements
    Abstract:

    Abstract Nanoemulsions are being increasingly utilized within the pharmaceutical, food, personal care, and chemical industries because of their unique physicochemical properties and functional performances: high optical clarity; prolonged stability; enhanced bioavailability; and novel rheology. For commercial applications, it is important to be able to produce nanoemulsions containing small droplets using efficient homogenization processes. In this study, we compared two Microfluidization methods for fabricating nanoemulsions: (i) single-channel Microfluidization and (ii) dual-channel Microfluidization. The influence of emulsifier concentration, homogenization pressure, disperse phase volume fraction, and initial emulsifier location (oil versus water phase) on particle size was examined. For both devices, the mean particle diameter decreased with increasing emulsifier concentration and homogenization pressure, and there was a linear log–log relationship between mean particle diameter and homogenization pressure. At a similar emulsifier level and homogenization pressure, dual-channel Microfluidization produced smaller droplets and narrower distributions than single-channel Microfluidization. This effect was attributed to a higher droplet disruption efficiency and/or lower droplet recoalescence rate for the dual-channel system. The dual-channel method could successfully produce nanoemulsions even at high oil concentrations (50%), whereas the single-channel method was only effective at producing nanoemulsions at relatively low oil concentrations (10%). This study demonstrates that dual-channel Microfluidization is an efficient means of producing fine nanoemulsions with high oil loading levels, which may be advantageous for many commercial applications.

Behic Mert - One of the best experts on this subject based on the ideXlab platform.

  • characterization and evaluation of emulsifying properties of high pressure microfluidized and ph shifted corn gluten meal
    Innovative Food Science and Emerging Technologies, 2019
    Co-Authors: Oguz Kaan Ozturk, Behic Mert
    Abstract:

    Abstract This study presents a potential application for adding value to corn gluten meal, which is often used as animal feed and underutilized in food industry. This study is aimed to improve water holding ability of zein-rich by product corn gluten and investigate possibility of using it as an emulsifier. The potential use of Microfluidization (500–1250 bar and 25 °C) and pH shifting (to pH6, 8, and 10) as a modification process for corn gluten meal and their effects on emulsifying properties were investigated. The formulations used for CGM(g):corn oil (mL) mixtures were 5:15, 5:30, 5:50, 10:15, 10:30, 10:50, 15:15, 15:30, and 15:50. Microfluidization and pH modification decreased the particle size of emulsions, resulting in the formation of tissues and micropores, and a consequent increase in surface area and water-holding capacity. pH shifting in dispersions around neutrality (pH6 and pH8) provided improvements in emulsion properties; however, excessive shifting (pH10) caused protein denaturation. Herschel-Bulkley model was well-fitted to explain flow behaviors. Flow and viscoelastic measurements showed that all formulations exhibited shear thinning and elastic gel-like behavior. The sedimentation rate, measured using LUMiSizer, was decreased by Microfluidization and pH modifications. This study showed that these treatments can be used to convert an underutilized material into a valuable one in food industry.

  • effect of Microfluidization on the microstructure and physical properties of a novel yoghurt formulation
    Journal of Food Engineering, 2018
    Co-Authors: Ilkem Demirkesen, Thomas A Vilgis, Behic Mert
    Abstract:

    Abstract This study aims at development of a new method to form emulsion-based yoghurt like gels from, but not limited to hazelnut. For this purpose, hazelnut slurries with varying solid content were processed using a microfluidizer to obtain creamy structures possessing high consistency. Then, these slurries were processed into fermented hazelnut products (HNPs) by inoculating with lactic acid bacteria culture. Real time rheological measurements were conducted to monitor how moduli values changed during fermentation. For the sake of comparison conventional cow milk yoghurt (CMY) was also included in the study. Texture analysis experiment showed that Microfluidization greatly improved physical properties of the HNPs with significant increase in firmness values. When moisture content of HNP was around 22.7%, the firmness value was close to that of CMY. Since the entire hazelnut was used in processing, the HNPs contained soluble (0.34–0.75 g/100 g) and insoluble fiber (1.58–4.12 g/100 g). Microfluidization treatment also resulted in markedly increased colloidal stability of the HNPs. Sensory evaluation studies revealed that some of the HNP formulations had comparable texture, flavor, and appearance properties with CMY.

  • the use of Microfluidization for the production of xanthan and citrus fiber based gluten free corn breads
    Lwt - Food Science and Technology, 2018
    Co-Authors: Oguz Kaan Ozturk, Behic Mert
    Abstract:

    Abstract Corn gluten meal is an underutilized byproduct due to its hydrophobic nature although it contains high amount of protein. The primary objectives of this study were to enhance the water holding capacity of this protein-rich byproduct with Microfluidization technique and use it in bread-making formulations instead of gluten with the addition of different supplements. The increase in stability, surface area, and consequently water holding capacity with Microfluidization resulted in the formation of compatible and homogeneous dough structure for gluten-free bread formulations. The dough exhibited linear viscoelastic behavior at strains lower than 0.5%. Elastic moduli were higher than viscous moduli for all formulations, meaning solid-like behavior. The addition of xanthan and citrus fiber resulted in higher moduli values. The decrease in particle size and the emergence of new tissues resulted in revealing of carotenoids like lutein and zeaxanthin, responsible for the yellow color of corn gluten meal. The breads produced from microfluidized samples had 1.19–1.27 times higher specific volumes than untreated samples of the same formulation. Similar improvements (1.03–1.22) were obtained with the addition of xanthan and citrus fiber. Both Microfluidization treatment and the addition of supplements led to lower hardness, and higher cohesiveness and springiness values.

  • the effects of Microfluidization on rheological and textural properties of gluten free corn breads
    Food Research International, 2018
    Co-Authors: Oguz Kaan Ozturk, Behic Mert
    Abstract:

    Abstract This study presents the potential of Microfluidization as a value adding process to corn gluten meal (CGM), which is often used as animal feed and is underutilized in food industry. In this study, we aimed to improve water holding ability of corn gluten and to investigate possibility of using this zein-rich byproduct as the main ingredient in gluten-free bread formulations. For this reason, Microfluidization as a milling process for CGM, and its effects on rheological and textural properties of gluten-free bread formulations were investigated. In addition, the effects of pH modification and hydrocolloids were analyzed. Microfluidization led to a higher surface area by disintegrating the large CGM molecules, and the structure became compatible to be used in gluten-free bread formulations by overcoming hydrophobic nature. However, structural deformations were detected with pH modifications. The linear viscoelastic region of dough was observed at strains lower than 0.5%. For all formulations, elastic moduli (G') were higher than viscous moduli (G") indicating solid-like behavior. The addition of HPMC and guar resulted in higher moduli values. Microfluidization and pH modifications provided brighter color by revealing lutein and zeaxanthin due to decreased particle size. Texture profile showed that Microfluidization and hydrocolloids decreased hardness, increased springiness and cohesiveness, which are desired characteristics for bread. Lastly, the addition of hydrocolloids led to an increase in specific volume by providing gas retention within the structure. HPMC provided 1.23–1.62 times bigger samples than control samples while it was only 1.02–1.12 times bigger for samples with guar according to specific volume analysis.

  • Production of Microfluidized Wheat Bran Fibers and Evaluation as an Ingredient in Reduced Flour Bakery Product
    Food and Bioprocess Technology, 2014
    Co-Authors: Behic Mert, Ilkem Demirkesen, Aziz Tekin, Gonul Kocak
    Abstract:

    In this study, the potential use of Microfluidization as a milling process for wheat bran was evaluated. More specifically, the influences of regular wheat bran and microfluidized wheat bran on quality (hardness, cutting force, specific volume, and color) and storage characteristics of model bakery product cake were compared. Microfluidization process led to formation of the finely separated fibrous structure with great surface area that allowed higher water holding capacity and methanol soluble-free phenolic content. Rheological measurements showed that the increased surface area of fibers also allowed bran fiber to intertwine and form strong fibrous matrix resulting in higher consistency index, yield stress, and viscoelastic moduli values in batter samples. Various flour formulations have been also tested in the presence of microfluidized wheat bran, and in reduced flour-containing samples, a fibrous network provided gluten-like strength to the batter and cake samples. Microfluidized wheat bran also affected color of cake samples. High water holding ability of microfluidized wheat bran had also impact on moisture loss and staling rate of the cake samples. These results show that microfluidized wheat bran could be an alternative functional ingredient in bakery products.

Chuan-he Tang - One of the best experts on this subject based on the ideXlab platform.

  • Microfluidization as a potential technique to modify surface properties of soy protein isolate
    Food Research International, 2012
    Co-Authors: Lan Shen, Chuan-he Tang
    Abstract:

    Abstract Modifications in physicochemical, conformational and emulsifying properties of unheated and preheated soy protein isolates (SPIs) by Microfluidization at a specific pressure level (120 MPa) were investigated. The heat pretreatment was carried out at temperatures of 75, 85 and 95 °C, respectively. The tested properties included protein solubility (PS), surface hydrophobicity (Ho), free sulfhydryl group (SH) and disulfide bond (SS) contents, conformational characteristics, as well as emulsifying properties (e.g. emulsifying ability index (EAI), particle size of oil droplets in the emulsions, creaming index). The results indicated that the Microfluidization treatment generally increased PS, Ho, SS content, as well as EAI of both unheated and preheated SPIs, in a preheating temperature dependent way; the treatment also resulted in partial unfolding and denaturation, and even structural re-arrangement of the proteins; the treatment improved the emulsifying efficiency and stability against creaming, but accelerated the bridging flocculation of oil droplets in the preheated-SPI-stabilized emulsions, with higher extent of flocculation observed at higher temperatures of the pretreatment. Size exclusion chromatography and SDS-PAGE analyses confirmed that the Microfluidization led to transformation of insoluble aggregates into soluble ones, in which SH/SS interchanges might be involved. The findings suggest that the Microfluidization treatment, or in combination with a thermal pretreatment, would be an effective technique to improve surface properties of SPI.

  • Cold, gel-like whey protein emulsions by microfluidisation emulsification: Rheological properties and microstructures
    Food Chemistry, 2011
    Co-Authors: Fu Liu, Chuan-he Tang
    Abstract:

    Novel cold, gel-like whey protein concentrate (WPC) emulsions at various oil fractions (; 0.2-0.6) were formed through thermal pretreatment (at 70 °C for 30 min) and subsequent microfluidisation. The rheogical properties and microstructures, as well as emulsification mechanism of these emulsions were characterised. The rheological analyses indicated that the gel-like emulsions exhibited shear-thinning and predominantly elastic gel behaviours, and the apparent viscosities and the mechanical moduli of the emulsions remarkably and progressively increased with increasing the from 0.2 to 0.6. Confocal laser scanning microscopy analyses confirmed close relationships between rheological properties and gel network structures at various values. The formation of the gel-like network structure was closely related to the high emulsifying efficiency by microfluidisation. This kind of novel gel-like emulsion might exhibit great potential and be applicable in food formulations, e.g. as a kind of carrier for heat-labile and active ingredients. © 2011 Elsevier Ltd. All rights reserved.

Mark A E Auty - One of the best experts on this subject based on the ideXlab platform.

  • the effect of high pressure Microfluidization on the structure and length distribution of whey protein fibrils
    International Dairy Journal, 2011
    Co-Authors: Daniela Oboroceanu, Lizhe Wang, Ardy Kroesnijboer, Andre Brodkorb, Paul Venema, Edmond Magner, Mark A E Auty
    Abstract:

    Abstract The effect of high pressure Microfluidization on native β-lactoglobulin (β-lg) or whey protein isolate (WPI), both before and after heat-induced protein fibril formation at pH 2.0, was investigated using atomic force microscopy (AFM), shear birefringence, reversed phase-high pressure liquid chromatography, attenuated total reflectance–Fourier transform infrared spectroscopy and fluorescence spectroscopy. The morphology and length distribution of the fibrils were determined using AFM and flow-induced birefringence, respectively. High pressure (≥50 MPa) Microfluidization treatment of β-lg induced ∼30% protein denaturation, accompanied by changes in secondary structure. Fibrils formed from high pressure treated β-lg or WPI were similar in length to fibrils formed from non-pressure treated proteins. High pressure (≥50 MPa) Microfluidization of fibrils formed from β-lg or WPI resulted in their breakup into more uniformly sized and much shorter fibrils. Microfluidization pressures of up to 170 MPa resulted in slightly shorter fibrils but did not completely dissociate them.

  • comparison of the effects of high pressure Microfluidization and conventional homogenization of milk on particle size water retention and texture of non fat and low fat yoghurts
    International Dairy Journal, 2010
    Co-Authors: Alan L Kelly, Chr Ian E Ciron, Mark A E Auty
    Abstract:

    The effect of high-pressure homogenization using a Microfluidizer® on texture, water-holding capacity, and extent of syneresis on stirred yoghurts was compared with that of conventional homogenization. The effect of homogenization condition on particle size was also assessed in milk and in yoghurt. Stirred yoghurts were prepared from recombined milk samples (0 and 1.5% fat) heat-treated (95 °C, 2 min) and then treated by conventional valve homogenization at 25 MPa or Microfluidization at 150 MPa. Homogenization conditions influenced the particle size in milk, gel particle size, and textural quality of stirred yoghurts in a manner dependent upon fat content. Milk microfluidized at 150 MPa had smaller particle size than homogenized milk, but resulted in larger particles in yoghurt. Microfluidization of low-fat milk modified the microstructure of yoghurt, giving more interconnectivity in the protein networks with embedded fat globules, but with similar texture profiles and water retention compared with yoghurt made from conventionally homogenized milk.

Tao Wang - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Microfluidization on microstructure, protein profile and physicochemical properties of whole cowpea flours
    Innovative Food Science and Emerging Technologies, 2019
    Co-Authors: Sarah Adjei-fremah, Tao Wang, Mulumebet Worku, Maria Ortiz De Erive, Fuli He, Guibing Chen
    Abstract:

    Abstract Whole cowpea flours from three cultivars were microfluidized through a 200 μm “Z” type interaction chamber at room temperature for two passes. The confocal micrographs showed the Microfluidization process could effectively disintegrate the structure of both cotyledon and seed coat, two major components of a cowpea seed. Disruption of cotyledon released the embedded starch granules and proteins, whereas disruption of seed coat generated large amounts of fiber fragments with amorphous and fluffy microstructure. Depending on the cultivars of cowpea, these effects significantly decreased mean particle size by up to 92.3% and bulk density by up to 68.7%, and increased specific surface area by up to 286.4%, swelling capacity by up to 107.7%, water-holding capacity by up to 16.1%, oil-holding capacity by up to 162.1%, and total water extractable proteins of whole cowpea by up to 39.7%. Reduced intensity of protein bands in SDS-PAGE was also observed. This indicated high pressure and high shear stress during Microfluidization induced fundamental structural changes of cowpea proteins. Under the present experimental conditions, the Microfluidization process had no apparent effects on both particle size and structure of cowpea starch granules present in the flours.

  • effect of microfluidisation on antioxidant properties of corn bran
    Food Chemistry, 2014
    Co-Authors: Julia Raddatz, Zhanxiang Zhou, Tao Wang, Guibing Chen
    Abstract:

    The microfluidisation process was used to reduce the particle size and loosen the tight microstructure of corn bran. This process significantly increased corn bran’s antioxidant activity exhibited through a surface reaction phenomenon and the extractability of phenolic compounds after alkaline and acid hydrolysis. For corn bran microfluidised through an 87 μm interaction chamber for 5 passes, the two most largely increased phenolic acids released after alkaline hydrolysis were p-coumaric acid (51.1%) and ferulic acid (45.1%). On the other hand, high shear stress during microfluidisation caused partial dispersion or dissolution of free phenolic compounds in water which was lost after the process. It was also found that bran residues after alkaline and acid hydrolysis still exhibited strong antioxidant activity via a surface reaction phenomenon, probably indicating the conventional method based on solvent extraction and relatively mild alkaline and/or acid hydrolysis underestimates the total phenolic content and antioxidant activity of corn bran.

  • effects of Microfluidization on microstructure and physicochemical properties of corn bran
    Journal of Cereal Science, 2013
    Co-Authors: Julia Raddatz, Tao Wang, Guibing Chen
    Abstract:

    Abstract Corn bran was treated by the Microfluidization process and the resulting changes in its microstructure and physicochemical properties were examined. The results showed that the Microfluidization process could effectively decrease particle size of corn bran and loosen microstructure of the bran matrix. This led to a significant decrease in bulk density and increases in specific surface area. The swelling capacity, water-holding capacity, oil-holding capacity, and cation-exchange capacity increased by 140%, 90%, 140%, and 90%, respectively, after a total of 8 passes through the IC200 and IC87 chambers. In addition, microscopic analysis revealed a gradual disintegration of original cell wall structure and the dissociation of different bran tissues as the extent of Microfluidization treatment increased. Findings of this study highlighted the great potential of the Microfluidization process in producing a high-quality fiber ingredient from corn bran.

  • Effects of Microfluidization process on physicochemical properties of wheat bran
    Food Research International, 2012
    Co-Authors: Tao Wang, Zhanxiang Zhou, Guibing Chen
    Abstract:

    Abstract Wheat bran is a very important dietary fiber source which is widely used in the food industry in order to produce fiber enriched foods. Previous reports have demonstrated that physicochemical properties of insoluble dietary fibers determine their physiological effects when they are consumed, indicating modification of these properties may improve the fibers' physiological properties. In this study, the Microfluidization process was used to treat wheat bran and its effects on the bran's physicochemical properties were examined. The results showed that Microfluidization process could effectively decrease particle size and bulk density, and substantially increase specific surface area, water-holding capacity, swelling capacity, oil-holding capacity and cation-exchange capacity. Confocal micrographs showed that the process could also separate the structural components of wheat bran. These results suggested that Microfluidization process would provide an effective method to modify physicochemical properties of wheat bran and probably other cereal brans.