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biodiversity explorer

the web of life in southern Africa

Food and drink biodiversity:

Dairy products 



The milk we use daily comes from dairy cows, which have been selectively bred for high milk production from Bos primigenius (Cattle).


Acidophilus milk

Milk fermented with cultures of Lactobacillus acidophilus, used to improve gut functioning by modifying the bacterial flora in the intestine.


Traditional buttermilk

The liquid left behind from churning butter from cream. Traditionally, the cream was obtained from skimming it off milk and after a few days of accumulating cream, it was churned into butter. By this time, the cream had fermented slightly, so traditional buttermilk is likely to have undergone fermentation by lactic acid bacteria.


Cultured buttermilk

The buttermilk bought in stores is made from pasteurized, homogenized, low-fat milk that has been inoculated with Lactococcis lactis and Leuconostoc citrovorum bacteria, thus simulating traditionally produced buttermilk but with a final product that has a thicker consistency.



A popular fermented, slightly alcoholic, milk drink in Eastern Europe, Northern Europe and Russia. It is the result of fermentation of milk with kefir grains the latter containing fermenting bacteria and yeasts. Kefir grains grow during fermentation and are passed on from one kefir producer to another - so you can't produce them easily from scratch. Kefir is produced commercially by fermentation of milk with bacterial and yeast cultures.


Soured milk

Milk that has coagulated through the addition of an acid such as citric acid or acetic acid. Soured milk can also be produced through bacterial fermentation with cultured buttermilk and acidophilus milk being forms of this. Milk that has gone sour by itself is likely to contain toxins from fermentation by the wrong bacteria and should not be consumed.



Yoghurt is usually made by first heating milk to about 80C to kill undesirable bacteria and to break down milk proteins so that they set together rather than forming curds. It is cooled to a temperature of 45C and a culture (a small sample of yoghurt made previously will do) of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria is then added. The milk is left for 4-7 hours, maintained at 45C, during which time fermentation takes place. Other bacterial strains are sometimes added during or after the culturing process.




Butterfat is contained in cream in the form of tiny globules surrounded by phospholipid membranes. The process of churning the cream breaks these membranes, resulting in the  butterfat globules coagulating to form butter, and the remainder of the cream forming buttermilk (see above). The butter is more flavoursome if it is produced from fermented cream because fermentation introduces important aromatic compounds, especially diacetyl, which has a strong buttery flavour. Modern butter production usually involves taking fresh pasteurised cream and adding Lactococcus and Leuconostoc bacteria, which induces fermentation. It can also be produced from fresh cream and then adding flavourants.


Clarified butter

Produced by heating butter to its melting point and then cooling it; this results in the butter separating into three fractions: the top layer of whey proteins forms a skin and is removed; the middle layer consists of pure butterfat, which is poured off to produce clarified butter, and what remains is a mixture of water and casein proteins at the bottom.



Soft, unripened cheeses

Cottage cheese

The bacterium Lactococcus lactis is used in the early stages of production and Leuconostoc cremoris in the later stages.

Cream cheese

Produced through fermentation of cream by four different species of bacteria: Lactococcus lactis, Lactococcus diacetylactis, Streptococcus thermophilus and Lactobacillus bulgaricus.

Mozzarella cheese

Streptococcus thermophilus and Lactobacillus bulgaricus are the 2 species of bacteria used in the fermentation of milk to produce this cheese.


Soft, ripened cheeses

Brie cheese (origin: France)



Camembert cheese (origin: France)


Semisoft cheeses

Blue cheese (origin: France)


Roquefort cheese (origin: France)


Hard, ripened cheeses

Cheddar cheese (origin: UK)  
Edam cheese (origin: Netherlands)  
Gouda cheese (origin: Netherlands)  
Swiss cheese (origin: Switzerland)  

Very hard, ripened cheeses

Parmesan cheese (origin: Italy)