Casein, Caseinates, and Milk Protein Concentrates 175micelles by transglutaminase produces
nanogel particles, which also may serve as
delivery vehicles in food systems (Huppertz
and de Kruif 2008 ).
Individual caseins and casein - derived
peptides are gaining increasing attention due
to their potential role in the developing
market of physiologically functional foods,
or nutraceuticals. Physiologically, casein -
derived peptides have been implicated in the
nervous, cardiovascular, digestive, and
immune systems (Hartmann and Meisel
2007 , Silva and Malcata 2005 ). Casein phos-
phopeptides, CMP, and caseinomorphines
are the best studied casein - derived bioactive
peptides (Kilara and Panyam 2003 , Silva and
Malcata 2005 ). Many of the products are
commercially available in limited quantities
and have been used as dietary supplements
in functional foods and as pharmaceutical
preparations. However, the postulated health
benefi ts and the molecular mechanisms
underlying their bioactivities in vivo are
equivocal.
The versatility of casein - based ingredients
and the potential to further differentiate them
by improved separation and process modifi -
cation procedures ensures that casein - based
ingredients will continue to have a place as
valued ingredients in the food industry.References
Aimutis , W.R. 1995. “ Dairy protein usage in processed
and imitation cheese. ” Food Technology Europe
2 : 30 – 34.
Alvarez , E.M. , Risso , P.H. , Canales , M.A.M. , Pirs ,
M.S. , and Gatti , C.A. 2008. “ Hydrodynamic
properties — structure relationship for sodium casein-
ate in presence of calcium. ” Colloids and Sur-
faces A — Physicochemical and Engineering Aspects
327 : 51 – 56.
Anon 1991. “ Milk based ingredients. Composition, char-
acteristics and applications of milk protein concen-
trates. ” Food Marketing and Technology 5 : 23 – 24.
Barbano , D. 2004. “ Milk protein products — what are
they and what role do they play in lactose reduced
(low “ carb ” ) foods? ” Department of Agricultural
and Applied Economics, University of Wisconsin ,
Madison.teins by heat - induced proteolysis (Guo et al.
1989 ).
Milk protein concentrates are very stable
to heat treatment, as observed by a compari-
son of protein emulsions (5% protein:5% fat)
stabilized by MPC 80, sodium caseinate, or
calcium caseinate heated at 130 ° C (266 ° F)
for 13 minutes. The emulsions stabilized by
sodium caseinate or MPC 80 were stable,
whereas those made with calcium caseinate
were destabilized. In addition, the milk
protein concentrates that had the highest
protein load on the surface of emulsion drop-
lets were most stable to creaming on storage
(Zwijgers 1992 ).
The Future
Casein - based products have traditionally
been used for their ability to contribute to the
physical and sensory properties of foods.
There are emerging opportunities to increase
the use of casein - based products for nutrition
and functional foods.
An attractive value - added application of
micellar casein is its use in shelf - stable, high -
quality nutrition beverages (Barbano 2004 ).
Micellar casein provides the mouth feel of
milk with approximately 2% fat without the
calories. An example is a low - fat, lactose -
free nutrition beverage with excellent fl avor
that is produced using micellar casein.
Milk proteins and casein - based products
are fi nding applications as encapsulating
matrices for the delivery of bioactive ingre-
dients through foods. When used in combi-
nation, or conjugated, with carbohydrates,
casein - based products have the potential for
site - specifi c delivery of oils and oil - soluble
bioactives to the gastrointestinal tract (Head
et al. 2005 ).
The casein micelle is a natural nano -
capsule. Hence, it may be harnessed to
deliver various food ingredients including
vitamins (Semo et al. 2007 ) and bioactives
(Sahu et al. 2008 ). Cross linking of the casein