Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Tonicity in Animals00:59

Tonicity in Animals

The tonicity of a solution determines if a cell gains or loses water in that solution. The tonicity depends on the permeability of the cell membrane for different solutes and the concentration of nonpenetrating solutes in the solution within and outside of the cell. If a semipermeable membrane hinders the passage of some solutes but allows water to follow its concentration gradient, water moves from the side with low osmolarity (i.e., less solute) to the side with higher osmolarity (i.e.,...
Tonicity in Animals01:16

Tonicity in Animals

Tonicity describes the amount of solute in a solution. The measure of the tonicity of a solution, or the total amount of solutes dissolved in a specific amount of solution, is called its osmolarity. Three terms—hypotonic, isotonic, and hypertonic—are used to relate the osmolarity of a cell to the osmolarity of the extracellular fluid that contains the cells. In a hypotonic solution, such as tap water, the extracellular fluid has a lower concentration of solutes than the fluid inside the cell,...
Viscosity01:17

Viscosity

When water is poured into a glass, it falls freely and quickly, whereas if honey or maple syrup is poured over a pancake, it flows slowly and sticks to the surface of the container. This difference in the flow of different kinds of liquids arises due to the fluid friction between the liquid layers and the liquid and the surrounding material. This property of fluids is called fluid viscosity. In this example, water has a lower viscosity than honey and maple syrup.
The SI unit of viscosity is...
Viscosity01:27

Viscosity

Viscosity is a property of fluids that measures their resistance to flow. It is influenced by factors such as the surface area of contact, the gradient of flow speed, and the fluid's viscosity constant, called the coefficient of viscosity. The coefficient of viscosity, also known as dynamic viscosity, is denoted by the symbol η. It determines the proportionality between the viscous force and the gradient of flow speed.Newton's law of viscosity states that the viscous force on a faster-moving...
Viscosity of Fluid01:19

Viscosity of Fluid

Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

THE PRODUCTION OF VOLATILE FATTY ACIDS BY BACTERIA OF THE DYSENTERY GROUP.

The Journal of general physiology·2009
Same author

THE VALUE OF MILK POWDER AGAR IN THE BACTERIOLOGICAL LABORATORY.

American journal of public health (New York, N.Y. : 1912)·1923
Same author

THE BROMINE CONTENT OF PUGET SOUND NEREOCYSTIS (GIANT KELP).

Science (New York, N.Y.)·1916
Same journal

Conformational changes upon pore blocker removal reveal conductive states of TMEM16A.

The Journal of general physiology·2026
Same journal

On the mechanism of hypomagnesemia with treatment-resistant seizures caused by variants of the Na+,K+-ATPase α1 subunit (ATP1A1).

The Journal of general physiology·2026
Same journal

Label-free real-time imaging of mitochondrial matrix volume changes and permeability transition in living cells.

The Journal of general physiology·2026
Same journal

Differential regulation of β1-dependent voltage shifts and kinetic modulation by an extracellular glutamate in NaV1.6 VSDIV.

The Journal of general physiology·2026
Same journal

Mechanistic insights into DCPIB inhibition of VRAC: Electrostatic control and binding plasticity.

The Journal of general physiology·2026
Same journal

An epilepsy-associated KV3.1 potassium channel variant acts via dominant-positive effect.

The Journal of general physiology·2026
See all related articles

Related Experiment Video

Updated: Jun 19, 2026

Challenges in Rheological Characterization of Highly Concentrated Suspensions — A Case Study for Screen-printing Silver Pastes
08:42

Challenges in Rheological Characterization of Highly Concentrated Suspensions — A Case Study for Screen-printing Silver Pastes

Published on: April 10, 2017

CASEIN VISCOSITY STUDIES.

H F Zoller1

  • 1Research Laboratories of the Dairy Division, Bureau of Animal Industry, United States Department of Agriculture, Washington.

The Journal of General Physiology
|October 30, 2009
PubMed
Summary
This summary is machine-generated.

Maximum casein viscosity in alkaline solutions occurs around pH 9.1-9.25, with ammonia yielding the highest viscosity. Heating casein solutions increases their viscosity, while alkaline hydrolysis at pH 10.0-10.5 causes casein to degrade.

More Related Videos

Molecular Entanglement and Electrospinnability of Biopolymers
07:59

Molecular Entanglement and Electrospinnability of Biopolymers

Published on: September 3, 2014

Biological Preparation and Mechanical Technique for Determining Viscoelastic Properties of Zonular Fibers
06:39

Biological Preparation and Mechanical Technique for Determining Viscoelastic Properties of Zonular Fibers

Published on: December 16, 2021

Related Experiment Videos

Last Updated: Jun 19, 2026

Challenges in Rheological Characterization of Highly Concentrated Suspensions — A Case Study for Screen-printing Silver Pastes
08:42

Challenges in Rheological Characterization of Highly Concentrated Suspensions — A Case Study for Screen-printing Silver Pastes

Published on: April 10, 2017

Molecular Entanglement and Electrospinnability of Biopolymers
07:59

Molecular Entanglement and Electrospinnability of Biopolymers

Published on: September 3, 2014

Biological Preparation and Mechanical Technique for Determining Viscoelastic Properties of Zonular Fibers
06:39

Biological Preparation and Mechanical Technique for Determining Viscoelastic Properties of Zonular Fibers

Published on: December 16, 2021

Area of Science:

  • Biochemistry
  • Physical Chemistry
  • Food Science

Background:

  • Casein, a major milk protein, exhibits complex behavior when dissolved in alkaline solutions.
  • Understanding casein's solution properties is crucial for food processing and biochemical applications.

Purpose of the Study:

  • To investigate the relationship between pH, alkali type, and casein solution viscosity.
  • To determine the optimal conditions for maximum casein viscosity.
  • To elucidate the mechanisms behind viscosity changes, including alkaline hydrolysis and thermal effects.

Main Methods:

  • Preparation of casein solutions using various alkali hydroxides (NaOH, KOH, LiOH, NH4OH) and salts (carbonates, phosphates, etc.).
  • Measurement of solution viscosity across a range of pH values.
  • Analysis of casein degradation products under alkaline hydrolysis conditions.

Main Results:

  • Maximum viscosity for casein solutions in most alkalies was observed between pH 9.1 and 9.25.
  • Ammonia solutions exhibited the highest viscosity.
  • Casein solutions prepared from heated casein (≥60°C) showed significantly higher viscosity.
  • Alkaline hydrolysis, initiating at pH 10.0-10.5, led to casein cleavage and decreased viscosity.

Conclusions:

  • The pH range of 9.1-9.25 is optimal for achieving maximum viscosity in casein solutions with various alkalis.
  • Ammonia is particularly effective in increasing casein solution viscosity.
  • Thermal processing of casein enhances its viscosity in alkaline media.
  • Alkaline hydrolysis is a key factor in the degradation of casein structure and viscosity reduction at higher pH levels.