Milk-and-Dairy-Products-in-Human-Nutrition-FAO

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Milk and dairy products in human nutrition
3.3.8 Casein
Casein (0917): The main protein constituent of milk. Casein is obtained from
skimmed milk by precipitation (curdling) with acids or rennet.
The CODEX standard for edible casein products (FAO and WHO, 2010k)
specifies acceptable composition of rennet casein, acid casein and caseinates.
Caseins are low in sulphur amino acids, which limits their biological value (Fox and
McSweeney, 1998).
3.3.9 Milk products from milk from underutilized species
With the exception of some fermented milks and milk powder made from mare
milk, most of the milk products presented in the preceding sections are made from
milk from common dairy animals (cow, sheep, goat and buffalo). Data on milk
products from milk from underutilized species are less common in literature, and
are outlined below.
Reindeer milk
Reindeer milk is important in the summer diet of herders, dried in curd form, or
made into cheese, butter and sour cream. The fat content increases significantly as
lactation progresses (see Section 3.2.3). The milk from the first part of the lactation
is drunk, milk from mid-lactation is used for cheese-making and milk from late
lactation is churned to produce butter (Holand, Gjøstein and Nieminen, 2006).
Yak milk
Mongolian people use yak milk to produce a range of food products, including the
fermented milk products kurut (Section 3.3.3) and koumiss, yoghurt, fresh cheese
and two types of butter, one of which is used for daily consumption. The other,
consisting of protein and fat, is called “white butter” and is used as food during
the winter in mixtures with sugar and other products (Indra and Magash, 2002).
Yak cheese (a hard, Swiss-style Gruyére cheese) is produced in Nepal, Mongolia,
Bhutan, India and Pakistan (FAO, 2003), with the yak cheese industry being of
significant importance for rural income and employment in Nepal.
Camel milk
Although most camel milk is consumed raw or in the form of fermented milk, commercial
farms supply fresh pasteurized milk in Saudi Arabia (Mehaia et al., 1995).
Bactrian camel milk is used for making cheese, butter and yoghurt in Mongolia
(Jirimutu et al., 2010). Studies on dromedary camel milk report that camel milk is
less favourable for cheese-making than cow, sheep and goat milk because it does not
produce a curd but rather produces flakes that lack firmness (Mehaia, 1997; Bornaz
et al., 2009). Dromedary camel milk has been shown to be suitable for buttermaking,
despite the belief among many camel-rearing societies that butter cannot
be made from camel milk (Streiff and Bachmann, 1989). The authors note that camel
cream has different churning properties to cream from cow milk and attribute these
differences to the high melting point of camel fat and small size of camel milk fat
globules. Bedouin in the Negev desert make ice cream from camel milk (Guliye,
Yagil and DeB Hovell, 2000), which is sold to tourists.