BLBS102-c11 BLBS102-Simpson March 21, 2012 13:9 Trim: 276mm X 219mm Printer Name: Yet to Come
230 Part 2: Biotechnology and Enzymologydevelopment differs; most of it takes place in the press, but the
principles remain the same (Kosikowski and Mistry 1997).
The development of proper acid in a curd mass controls the
microbial flora. Sufficient lactic acid produced at optimum rates
favors lactic acid bacteria and discriminates against spoilage
or food poisoning bacteria such as coliforms, clostridia, and
coagulase-positive staphylococci. But its presence does more
than that, for it transforms the chemistry of the curd to provide
the strong bonding that is necessary for a smooth, integrated
cheese mass.
As discussed earlier, chymosin action on milk results in curd
mass involving dicalcium paracasein. Dicalcium paracasein is
not readily soluble, stretchable, or possessive of a distinguished
appearance. However, if sufficient lactic acid is generated, this
compound changes. The developing lactic acid solubilizes con-
siderable calcium, creating a new compound, monocalcium
paracasein. The change occurs relatively quickly, but there is
still a time requirement. For example, a Cheddar cheese curd
mass, salted prior to pressing, may show an 8:2 ratio of dical-
cium paracasein to monocalcium paracasein; after 24 hours in
the press, it is reversed, 2:8. Monocalcium paracasein has in-
teresting properties. It is soluble in warm 5% salt solution, it
can be stretched and pulled when warmed, and it has a live,
glistening appearance. The buildup of monocalcium paracasein
makes a ripened cheese pliable and elastic. Then, as more lactic
acid continues to strip off calcium, some of the monocalcium
paracasein changes to free paracasein as follows:Dicalcium paracasein+lactic acid
→monocalcium paracasein+calcium lactate
Monocalcium paracasein+lactic acid
→free paracasein+calcium lactateFree paracasein is readily attacked by many enzymes, con-
tributing to a well-ripened cheese. The curd mass becomes fully
integrated upon the uniform addition of sodium chloride, the
amount of which varies widely for different cheese types. Salt
directly influences flavor and arrests sharply the acid production
by lactic acid starter bacteria. Also, salt helps remove excess
water from the curd during pressing and lessens the chances
for a weak-bodied cheese. Besides controlling the lactic acid
fermentation, salt partially solubilizes monocalcium paracasein.
Thus, to a natural ripened cheese or to one that is heat processed,
salt helps give a smoothness and plasticity of body that is not
fully attainable in its absence.
Texture of cheese is affected significantly during ripening, es-
pecially during the first 1–2 weeks, according to Lawrence et al.
(1987). During this period, the alpha-s-1-casein is hydrolyzed
to alpha-s-1-I by residual chymosin, making the body softer
and smoother. Further proteolysis during ripening continues to
influence texture.REFERENCES
Andren A. 2003. Rennets and coagulants. In: H Roginski, JW
Fuquay, PF Fox, editors.Encyclopedia of Dairy Sciences. Lon-
don: Academic Press, London, pp. 281–286.Banks JM. 1992. Yield and quality of Cheddar cheese produced
using a fermentation-derived calf chymosin.Milchwissenschaft
47: 153–201.
Barbano DM, Rasmussen RR. 1992. Cheese yield performance of
fermentation-produced chymosin and other milk coagulation.J
Dairy Sci75: 1–12.
Biner VEP, Young D, Law BA. 1989. Comparison of Cheddar
cheese made with a recombinant calf chymosin and with standard
calf rennet.J Dairy Res56: 657–664.
Brown GD. 1971. Microbial enzymes in the production of Cottage
cheese. MS Thesis. Ithaca NY: Cornell University.
Collin J-C. et al. 2003. Detection of fermentation produced chy-
mosin. In: Bulletin 380. Brussels Belgium: Int Dairy Fed.
pp. 21–24.
Dalgleish DG. 1992. Chapter 16. The enzymatic coagulation of
milk. In: PF Fox (ed.)Advanced Dairy Chemistry. Vol 1, Proteins.
Essex England: Elsevier Sci Publ Ltd.
Duxbury DD. 1990. Cheese enzyme is first rDNA technology de-
rived food ingredients granted GRAS approved by FDA. Food
Proc (June): 46.
Edwards JL. 1969. Bitterness and proteolysis in Cheddar cheese
made with animal, microbial, or vegetable rennet enzymes. PhD
Thesis. Ithaca NY: Cornell University.
Esteves CLC, Lucey JA. 2002. Rheological properties of milk gels
made with coagulants of plant origin and chymosin.Int Dairy J
12: 427–434.
Ferron-Baumy C. et al. 1991. Coagulation presure du lait et des ́
retentats d’ultrafiltration. Effets de divers traitements thermiques. ́
Lait71: 423–434.
Farntiam MG, inventor. 1964, September 27. Cheese modifying
enzyme product. U.S. patent 3,531,329.
Foltmann B. 1993. General and molecular aspects of rennets. In: PF
Fox (ed.)Cheese: Chemistry, Physics and MicrobiologyVol. 1,
2nd edition. New York: Chapman and Hall, pp. 37–68.
Fox PF. et al. 1993. Biochemistry of cheese ripening. In: PF Fox
(ed.)Cheese: Chemistry, Physics and Microbiology, 2nd edition,
vol. 1. New York: Chapman and Hall.
Green ML. 1977. Review of progress of dairy science: Milk coag-
ulants.J Dairy Res44: 159–188.
Green ML. et al. 1985. Cheddar cheesemaking with recombinant
calf chymosin synthesized in Escherichia.J Dairy Res52: 281.
Hicks CL, O’Leary J, Bucy J. 1988. Use of recombinant chymosin
in the manufacture of Cheddar and Colby cheeses.J Dairy Sci
71: 1127–1131.
Horne DS. 1998. Casein interactions: Casting light on the black
boxes, the structure in dairy products.Int Dairy J8: 171–177.
IDF. 1992. Fermentation produced enzymes and accelerated ripen-
ing in cheesemaking. Bulletin No. 269. Brussels Belgium: Int
Dairy Fed.
Kosikowski FV, Mistry VV. 1997.Cheese and Fermented Milk
Foods. Vol 1, Origins and Principles. Great Falls, Virginia: FV
Kosikowski.
Lawrence RC. et al. 1987. Texture development during cheese ripen-
ing.J Dairy Sci70: 1748–1760.
Ledford RA. et al. 1966. Residual casein fractions in ripened cheese
determined by polyacrylamide-gel electrophoresis.J Dairy Sci
49: 1098–1101.
Lomholt SB, Qvist KB. 1999. Gel firming rate of rennet curd as a
function of rennet concentration.Int Dairy J9: 417–418.