Acidic and Heat Processing of Egg Yolk Dispersions

Egg yolk is a multifunctional ingredient widely used in many food products, wherein proteins are the dominant component contributing to this functionality. However, the potential risk of foodborne illness associated with egg use forces us to ensure that foodstuffs based on egg yolk are managed in a safe and sanitary manner. Lowering the pH under a certain value by adding acids could serve this purpose, but it can also greatly modify the rheological and functional properties of egg yolk. This research aims to assess the influence of citric acid on the rheological properties and microstructure of chicken egg yolk dispersions and their heat-set gels. The dispersions were prepared from fresh hen’s eggs yolks by adding water or citric acid to obtain a technical yolk (45 wt.% in solids) at the desired pH value. Viscoelastic measurements were carried out using a control stress rheometer, and microstructure was evaluated by cryo-scanning electronic microscopy (CryoSEM). An evolution of the viscoelastic properties of egg yolk dispersions from fluid to gel behavior was observed as the pH decreased until 2 but showing a predominantly fluid behavior at pH 3. The profile of viscoelastic properties along the thermal cycle applied is modified to a great extent, also showing a strong dependence on pH. Thus, the sol–gel transition can be modulated by the pH value.

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Egg yolk gels: Sol-gel transition and mechanical properties as affected by oleuropein enrichment

Food Hydrocolloids ◽

10.1016/j.foodhyd.2018.06.023 ◽

2018 ◽

Vol 84 ◽

pp. 435-440 ◽

Cited By ~ 5

Author(s):

Carla D. Di Mattia ◽

Giampiero Sacchetti ◽

Lilia Neri ◽

Veronica Giacintucci ◽

Valerio Cerolini ◽

...

Keyword(s):

Mechanical Properties ◽

Sol Gel ◽

Egg Yolk ◽

Sol Gel Transition ◽

Gel Transition

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Role of viscoelasticity in the tube model of airway reopening. II. Non-Newtonian gels and airway simulation

Journal of Applied Physiology ◽

10.1152/jappl.1996.80.5.1649 ◽

1996 ◽

Vol 80 (5) ◽

pp. 1649-1659 ◽

Cited By ~ 12

Author(s):

S. H. Hsu ◽

K. P. Strohl ◽

M. A. Haxhiu ◽

A. M. Jamieson

Keyword(s):

Viscoelastic Properties ◽

Flow Instability ◽

Sol Gel ◽

Tube Model ◽

Airway Reopening ◽

Pharyngeal Airway ◽

Airway Tube ◽

Sol Gel Transition ◽

Gel Transition

The influence of viscoelastic gels as lining fluids on the pressure-velocity relationships in an airway tube model (Gaver et al. J. Appl. Physiol. 69: 74-85, 1990) was examined. A flow instability was observed due to the occurrence of a sol-gel transition in the viscoelastic properties under flow conditions. We further report measurements of the viscoelastic properties of airway secretions. Airway secretions are gels under small strains and have a yield stress of 4-7 dyn/cm2. Secretions from the pharyngeal airway show lower elasticity than secretions from the trachea. The airway reopening process is simulated using a Weibel lung geometry by incorporating the constitutive equations from the model gel studies and utilizing the rheological data on airway secretions. In these simulations, a "popping-open" phenomenon arises from a flow instability in airway generations 8-14 when the rheological properties of the lining fluids are assumed to be similar to those of pharyngeal secretions. On the basis of these studies, the elasticity of airway secretions plays an important role in airway reopening.

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Preparation of Lanthanum Molybdate Powers by Sol-Gel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.412.121 ◽

2011 ◽

Vol 412 ◽

pp. 121-124

Author(s):

Zhao Yang Fei ◽

Jiang Hong Gong

Keyword(s):

Citric Acid ◽

Aging Time ◽

Sintering Temperature ◽

Ph Value ◽

Raw Materials ◽

Sol Gel ◽

Ammonium Molybdate ◽

Lanthanum Nitrate ◽

Lanthanum Molybdate

Lanthanum molybdate powders were prepared by sol-gel using lanthanum nitrate, ammonium molybdate, citric acid as the main raw materials. The prepared powders were characterized by XRD, SEM, BET and other methods. It is concluded that the best sintering temperature was 550°C, the aging time was 1h and the best ph value was 1.5.

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Scaling Behaviour of the Viscoelastic Properties of a Biopolymer System Near the Gel Point

MRS Proceedings ◽

10.1557/proc-177-199 ◽

1989 ◽

Vol 177 ◽

Cited By ~ 1

Author(s):

M. A. V. Axelos ◽

M. Kolb

Keyword(s):

Steady State ◽

Percolation Theory ◽

Viscoelastic Properties ◽

Sol Gel ◽

Oscillatory Shear ◽

Gel Point ◽

Rheological Measurements ◽

Scaling Behaviour ◽

Sol Gel Transition ◽

Gel Transition

ABSTRACTRheological measurements have been performed on pectin-calcium systems close to the sol-gel transition. Two different experimental setups - steady state and oscillatory shear measurements - show scaling of the viscoelastic properties. The results of both types of measurements are consistent with each other and with scalar percolation theory.

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Effect of dimethylsulfoxide on the viscoelastic properties and sol–gel transition of cellulose/ionic liquid solutions

RSC Advances ◽

10.1039/c4ra14911d ◽

2015 ◽

Vol 5 (11) ◽

pp. 8318-8322 ◽

Cited By ~ 10

Author(s):

H. Saba ◽

Y. Yongbo ◽

W. Jianning ◽

X. Xiaolin ◽

W. Kaijian ◽

...

Keyword(s):

Ionic Liquid ◽

Viscoelastic Properties ◽

Sol Gel ◽

Liquid Solutions ◽

Sol Gel Transition ◽

Rheological Experiments ◽

Gel Transition

Viscoelastic properties of cellulose solutions with 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and dimethylsulfoxide (DMSO) as solvents were studied by rheological experiments.

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Comparison of chicken-egg yolk and duck-egg yolk in tris-citric acid as extender to maintain the quality of post-thawing Bali bull semen

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/788/1/012148 ◽

2021 ◽

Vol 788 (1) ◽

pp. 012148

Author(s):

K Khatimah ◽

M Yusuf ◽

R F Utami ◽

A L Toleng ◽

Masturi ◽

...

Keyword(s):

Citric Acid ◽

Egg Yolk ◽

Chicken Egg ◽

Bull Semen ◽

Duck Egg ◽

Chicken Egg Yolk

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Viscoelastic Properties for Sol-Gel Transition

Rheology ◽

10.5772/36550 ◽

2012 ◽

Cited By ~ 4

Author(s):

Yutaka Tanaka

Keyword(s):

Viscoelastic Properties ◽

Sol Gel ◽

Sol Gel Transition ◽

Gel Transition

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Preparation and Characterization of BaTiO3 Powders by Sol-Gel and BaTiO3 Ferroelectric Films by Electrophoretic Deposition Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.280-283.617 ◽

2007 ◽

Vol 280-283 ◽

pp. 617-622

Author(s):

Ya Lu Ma ◽

Hong Long Zhu ◽

Jian Lin Li

Keyword(s):

Electrophoretic Deposition ◽

Ph Value ◽

Sol Gel ◽

Transition Process ◽

Deposition Technique ◽

Ferroelectric Films ◽

Electrical Field Strength ◽

Powder Concentration ◽

Sol Gel Transition ◽

Gel Transition

The clear and transparent sols of BaTi acetate were prepared from tetrabutyltitanate, barium acetate aqueous solution, ethanol and acetic acid. The BaTi acetate sols were transferred into gels by sol-gel process, and the gels were dried and calcined to nanostructured BaTiO3 powders. Pure barium titanate powders added in mixtures of acetone and iodine and water or acetylacetone (Acac) and ethanol (EtOH) as suspension systems, the aim of this study was to use the electrophoretic deposition technique (EPD) to fabrication the BaTiO3 ferroelectric films with high dielectric constant. During sol-gel transition process, it is found that the initial PH value of sol affected not only the sol-gel transition, but also the particles size of the final calcined BaTiO3 powders. The effects of the EPD process parameters such as the suspension, powder concentration, electrical field strength on the specific EPD deposited weight were investigated. The films sintered at 1050°C for 2h were crystallized into the tetragonal phase at room temperature, which were sufficiently dense and had uniform microstructure and excellent dielectric properties.

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Effects of pH Value and Water Content of Sol on TiO2 Photocatalytic Activity Prepared by SAS

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.864 ◽

2013 ◽

Vol 774-776 ◽

pp. 864-867

Author(s):

Zai Feng Shi ◽

Su Min Zhang ◽

Su Guo

Keyword(s):

Methylene Blue ◽

Particle Size ◽

Photocatalytic Activity ◽

Citric Acid ◽

Water Content ◽

Mass Fraction ◽

Ph Value ◽

Sol Gel ◽

Raw Material ◽

Effects Of Ph

To investigate the effects of sol pH value and water content on photocatalytic activity of TiO2 prepared with sol-gel auto-igniting synthesis (SAS) method, TiO(NO3)2 was prepared with TiCl4 as raw material and used as precursor of TiO2. By changing sol pH value and water content, different TiO2 powders were prepared and characterized with XRD, SEM and photodegradation of methylene blue (MB). Results indicated that TiO2 presented the highest photocatalytic activity while sol pH value and mass fraction of water were adjusted to 7 and 50% respectively while the mole ratio of n (TiCl4): n (citric acid): n (ammonium nitrate) was fixed as 1: 1: 3. The TiO2 powders were confirmed as loose and porous anatase type with particle size of 15 nm by SEM and XRD.

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