Chemistry Reference
In-Depth Information
V. Reduced Lactose and Lactose-Free Dairy
Products
Shakeel-Ur-Rehman
V.1.
Introduction
The malabsorption of lactose by lactose-intolerant individuals, which has
been recognized since the 1950s (Holsinger and Kligerman, 1991), resulted in
the development of lactose-reduced or lactose-free milks, dairy products and
dairy beverages. The availability of lactose-reduced or lactose-free milks
offers an opportunity for the dairy industry to gain new consumers who
would otherwise avoid milk. Two approaches are commercially used to
manufacture lactose-free or lactose-reduced milks and dairy products, i.e.,
treatment with
-
D
-galactosidase and membrane processing. In dairy pro-
ducts like yoghurt and cheese, some of the lactose is converted to lactic acid
by bacterial action and in cheese most of the lactose (
98%) is lost in the
whey. Yoghurt and cheese, therefore, are naturally lactose-modified or
reduced-lactose dairy products. The
-
D
-galactosidase produced by some
lactic acid bacteria during the fermentation of lactose helps in lactose absorp-
tion in the human intestine (Flatz, 1987).
V.2.
Methods for the Manufacture of Lactose-Free
or Lactose-Reduced Milk Products
Three methods are used to reduce/modify or eliminate lactose in milk and
milk products.
Shakeel-Ur-Rehman
3162 E Deerhill Dr. Meridian, ID, 83642, USA.
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