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THE EFFECT OF RENNIN UPON CASEIN : I. THE SOLUBILITY OF PARACASEIN IN SODIUM HYDROXIDE
1Department of Physical Chemistry, Laboratories of Physiology, Harvard Medical School, Boston.
The Journal of General Physiology
|October 30, 2009
Summary
Paracasein, a modified casein, shows distinct physicochemical properties. Its base-binding capacity is 1.5 times greater than casein, differentiating it through scientific analysis.
Area of Science:
- Biochemistry
- Protein Chemistry
Background:
- Casein is a primary protein in milk.
- Understanding casein modifications is crucial for dairy science and food technology.
Purpose of the Study:
- To characterize paracasein, a modified form of casein.
- To investigate the physicochemical differences between paracasein and casein.
Main Methods:
- Preparation and purification of paracasein.
- Solubility studies of paracasein and casein in water and NaOH solutions at varying temperatures.
- Determination of base-binding capacity and equivalent combining weights.
Main Results:
- Purified paracasein exhibited solubility in water similar to casein at low temperatures.
- Paracasein demonstrated a significantly higher base-binding capacity (1.5 times greater) than casein.
- The equivalent combining weights ratio of paracasein to casein was approximately 2:3, suggesting identical temperature coefficients for NaOH solubility.
Conclusions:
- Paracasein is a distinct modification of casein.
- Physicochemical properties, particularly base-binding capacity, differentiate paracasein from casein.
- These findings provide a basis for identifying and utilizing paracasein in scientific and industrial applications.
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