Editing Casein (section)

====Protein supplements====
An attractive property of the casein molecule is its ability to form a gel or clot in the stomach, which makes it very efficient in nutrient supply. The clot is able to provide a sustained slow release of amino acids into the blood stream, sometimes lasting for several hours. This also happens when milk is consumed by an animal: the stomach proteases cause it to form a gel. Cheesemaking using [[rennet]] (see above) replicates this behavior.<ref>{{cite journal | vauthors = Boirie Y, Dangin M, Gachon P, Vasson MP, Maubois JL, Beaufrère B | title = Slow and fast dietary proteins differently modulate postprandial protein accretion | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 94 | issue = 26 | pages = 14930–14935 | date = December 1997 | pmid = 9405716 | pmc = 25140 | doi = 10.1073/pnas.94.26.14930 | doi-access = free | bibcode = 1997PNAS...9414930B }}</ref>

Casein is also a relatively abundant source of protein. One form (without the delayed-gelling property) is ''hydrolyzed casein'', whereby it is [[hydrolysis|hydrolyzed]] by a [[protease]] such as [[trypsin]]. This could result in quicker digestion or direct gel formation. Hydrolyzed forms are noted to taste bitter and such supplements are often refused by infants and lab animals in favor of intact casein.<ref>{{cite journal | vauthors = Field KL, Kimball BA, Mennella JA, Beauchamp GK, Bachmanov AA | title = Avoidance of hydrolyzed casein by mice | journal = Physiology & Behavior | volume = 93 | issue = 1–2 | pages = 189–199 | date = January 2008 | pmid = 17900635 | pmc = 2254509 | doi = 10.1016/j.physbeh.2007.08.010 }}</ref>