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

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Milk and dairy products in human nutrition
5.2.3 Lactose
Lactose, a disaccharide formed from glucose and galactose, is the principal carbohydrate
in milk; cow milk contains approximately 5 g of lactose/100 g. As well
as providing energy, lactose (along with milk oligosaccharides) supports growth,
aids in softening of stools and enhances water, sodium and calcium absorption
(Hernández-Ledesma, Ramos and Gómez-Ruiz, 2011). As discussed in Chapter 4,
lactose intolerance, which is caused by insufficient amounts or activity of lactase in
the human intestine, can result in varying degrees of abdominal discomfort, bloating,
diarrhoea and flatulence (Wilt et al., 2010).
5.2.4 Dairy ingredients
In recent decades, technological and research advances have enabled the dairy industry
to extract and modify dairy components into ingredients. A wide array of dairy
ingredients is commercially available. Such ingredients are predominantly used in
dairy foods. They are also found in bakery products, beverages, confectionery, dressings,
sauces, cereals and sports beverages. Edible lactose is often used in foods such
as bread, confectionaries and infant formula, as well as in non-food applications such
as animal feed and fermentation-culture media. Casein-derived peptides have been
used in pharmaceutical preparations and as dietary supplements (Nagpal et al., 2012).
Dairy ingredients can be used as processing aids in the manufacture of food. As
defined by CODEX Alimentarius, a “processing aid means any substance or material,
not including apparatus or utensils and not consumed as a food ingredient by
itself, intentionally used in the processing of raw materials, foods or its ingredients,
to fulfil a certain technological purpose during treatment or processing and which
may result in the non-intentional but unavoidable presence of residues or derivatives
in the final product”. (FAO and WHO, 2010b). However, caution must be
taken in labelling the final product as trace dairy ingredients may be present in the
final product. This is significant for components such as cow-milk protein that can
cause an adverse allergic reaction in susceptible consumers. It is imperative that any
associated risks with a dairy component are fully understood and communicated
to the consumer. In order to achieve a high level of protection for food-allergic
consumers, allergens such as cow-milk protein should be indicated on the label of
food products and alcoholic beverages such as wine; cow milk and/or its derivatives
may be used as processing aids in wine-making and traces may remain in the final
product (Kirschner et al., 2009). Recently, the EFSA released a scientific opinion
from the International Organisation of Vine and Wine (OIV) related to the use of
casein, caseinates and milk products as clarification processing aids 47 during the
manufacture of wine, which concluded that wines fined using these substances
may trigger an adverse reaction in susceptible individuals and the casein detection
techniques as proposed by OIV were insufficient to eliminate the risk (EFSA, 2011).
47 Clarification or fining of wines serves to remove insoluble and colloidal substances and astringent
compounds such as tannins from wine. Fining/clarification agents/aids that are commonly used
include casein from cow milk, fish gelatin and albumin and lysozyme (extracted from hens’ eggs)
(Kirschner et al., 2009).