Related Experiment Video
Updated: Jun 16, 2026
08:01
Synthesis of Monocyte-targeting Peptide Amphiphile Micelles for Imaging of Atherosclerosis
Published on: November 17, 2017
Modification to the renneting functionality of casein micelles caused by nonionic surfactants
G Ion Titapiccolo1, M Corredig, M Alexander
1Department of Food Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Journal of Dairy Science
|January 29, 2010
Summary
Tween 20, a nonionic surfactant, accelerates renneting in skim milk by directly impacting casein micelles, not enzyme activity. This leads to stronger gels with altered micelle size, offering insights into dairy gel structure design.
Area of Science:
- Food Science
- Colloid Science
- Dairy Chemistry
Background:
- Nonionic surfactants like polysorbates are common in dairy but their interaction with milk proteins is unclear.
- Understanding these interactions is crucial for dairy product formulation and processing.
Purpose of the Study:
- To investigate the effect of Tween 20 on casein micelles during rennet-induced gelation of skim milk.
- To elucidate the mechanism of interaction between nonionic surfactants and milk proteins.
Main Methods:
- Studied renneting behavior of skim milk with varying concentrations of Tween 20.
- Analyzed gel properties (elastic modulus, brittleness) and micelle characteristics.
- Varied surfactant size (Tween 20 vs. Tween 80) and protein colloidal state.
Main Results:
- Tween 20 accelerated both phases of skim milk renneting.
- Resulting gels exhibited increased elastic modulus but similar brittleness.
- Surfactant directly affected casein micelles, not rennet enzyme activity.
- Increased surfactant size reduced the impact on gelation point.
- Tween increased micelle size without affecting stability or free casein levels.
Conclusions:
- Nonionic surfactants interact directly with casein micelles, influencing rennet-induced gelation.
- Findings provide a basis for designing specific structures in rennet-induced dairy gels.
- Further research is needed to fully understand the enzymatic cleavage mechanism in the presence of these surfactants.
Related Concept Videos
01:30Micelles
Micelle formation is an intricate process that hinges on the properties of amphiphilic or amphipathic molecules and the conditions of the system in which they are found. Amphiphilic molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, play a critical role in this process.In aqueous environments, these molecules arrange themselves such that their hydrophilic heads are turned towards the water phase, while their hydrophobic tails are oriented away...
01:27Surface Active Agents
Surfactants, named for their behavior at interfaces, positively adsorb at the interfaces of two phases, reducing interfacial tension. Their versatility as emulsifiers, detergents, and foaming agents stems from this ability. Surfactants, often termed amphiphiles, share the property of amphipathy, with molecules having both hydrophilic and hydrophobic portions. The hydrophilic part is called the head, and the hydrophobic part, including an elongated alkyl substituent, forms the tail.Surfactants...
01:18Detergent Purification of Membrane Proteins
Detergents are used to purify the integral proteins of the membrane. The hydrophobic portion of the detergent can replace membrane phospholipids while solubilizing the membrane proteins. When detergent monomers reach a specific concentration in a solution called critical micelle concentration (CMC), they form micelles. Above CMC, the concentration of the detergent monomers remains in equilibrium with the micelle. The number of detergent monomers present in the CMC varies for each detergent, and...
03:22Colloids
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...
01:16Bioavailability Enhancement: Drug Solubility Enhancement
Bioavailability is a critical factor in determining a drug's effectiveness. It refers to the proportion of a drug that enters the circulation when introduced into the body and is, as a result, able to have an active effect. Enhancing bioavailability is essential for drugs with poor solubility, as it can significantly impact their therapeutic efficacy. Various methods are employed to increase the solubility of drugs, thereby enhancing their bioavailability.Micronization and nanonization are...