III. Products
Cheese
Cheese is yet another product of milk fermentation that requires factors in addition to the traditional production of lactic acid. The coagulation of casein due to lactic acid production and the subsequent drop in pH and the addition of rennet, an enzyme derived from the lining of the stomachs of calves, form the curd of cheese Without rennet, a soft cheese such as cottage cheese or cream cheese would result.
http://www.public.iastate.edu/~cfford/101Milk.htm Yeasts, molds, and bacteria are all involved in the processes that produce different cheeses, and their locations on or in the curd are what results in many cheese types. The table below shows the bacteria involved in different cheeses:
Species
Major known function
Product
Flavor & eye formation
Swiss cheese family
Lactobacillus bugaricus
Lactobacillus lactis
Lactobacillus helveticus
Acid and flavor
Bulgarian buttermilk, yogurt, kefir, koumiss, Swiss, Emmental, and Italian cheeses
Lactobacillus acidophilus
Acid
Acidophilus, buttermilk
Streptococcus thermophilus
Acid
Emmental, Cheddar, and Italian cheeses, and yogurt
Streptococcus diacetilactis
Acid
Sour cream, ripe cream, butter, cheese, buttermilk and starter cultures.
Streptococcus lactis
Streptococcus cremoris
Acid
Cultured buttermilk, sour cream, cottage cheese, all types of foreign and domestic cheeses, and starter cultures.
Streptococcus durans
Streptococcus faecalis
Acid and flavor
Soft Italian, cheddar, and some Swiss cheeses.
Leuconostoc citrovorum
Leuconostoc dextranicum
Flavor
Cultured buttermilk, sour cream, cottage cheese, ripened cream butter, and starter cultures.
http://www.science-projects.com/dairybacteria.htm
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