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Sigma's Non-specific Protease Activity Assay - Casein as a Substrate
Published on: September 17, 2008
THE EFFECT OF RENNIN UPON CASEIN : II. FURTHER CONSIDERATION OF THE PROPERTIES OF PARACASEIN
1Department of Physical Chemistry, Laboratories of Physiology, Harvard Medical School, Boston.
The Journal of General Physiology
|October 30, 2009
Summary
Paracasein is distinct from casein, even when casein is exposed to alkaline conditions or partial hydrolysis. This protein, paracasein, is not simply a modified form of casein.
Area of Science:
- Biochemistry
- Protein Chemistry
Background:
- Casein is a major milk protein with specific solubility properties.
- Understanding casein modifications is crucial for dairy science and food technology.
Purpose of the Study:
- To investigate the properties of paracasein and compare them with casein.
- To determine if paracasein is a derivative of casein.
Main Methods:
- Comparative analysis of casein and paracasein preparations.
- Solubility tests of casein under various alkaline and hydrolysis conditions.
Main Results:
- Casein maintains its solubility in sodium hydroxide (NaOH) even after significant alkali exposure, recovery from hydrolysis, or prolonged storage at its isoelectric point.
- Paracasein exhibits different properties compared to casein treated with excess alkali.
Conclusions:
- Paracasein is not identical to casein modified by alkaline treatment.
- The preparation of paracasein does not involve the partial hydrolysis of casein in the presence of NaOH.
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