MILK
-Milk is a white, opaque liquid mixture secreted by female mammals.
-Milk is to nourish newly born offspring. It is the sole source of nutrition for
babies, so it has to be complete in terms of nourishment.
Milk is composed of water, protein, fat, lactose, vitamins and minerals.
Differences between human milk and bovine milks are important in
understanding milk.
-Human milk has less protein than cow’s milk, so it is more easily digested.
-Human milk contains the “bifudus factor” a substance that promotes the growth
of Lactobacillus bifudus. This harmless bacterium populates the infant’s
digestive tract excreting lactic acid. This acid inhibits the growth of other,
harmful microbes.
-Mother’s milk contains antibodies, which fight against ingestible pathogens such
as polio, salmonella, and coliform bacteria.
Differences in Human milk and Cow milk
Percentage by weight
Water
Fat
Lactose
Vitamins & Minerals
Protein
Of the protein:
Casein
Whey
Human
87%
1.1%
6.8%
0.2%
1.1%
Cow
87%
3.5%
4.9%
0.7%
3.5%
40%
60%
82%
18%
Lactose: only found in milk, forsythia flowers, and a few tropical shrubs.
-A disaccharide made up of glucose and galactose.
-Broken down into monosaccharides by lactase. This peaks in a baby shortly
after birth and declines slowly for the next 3 ½ years.
-If large amounts of lactose are consumed in the absence of lactase, then the
sugar passes through the small intestine without being absorbed and into the
large intestine. Some colonic bacteria ferment lactose producing carbon dioxide
gas that causes real distress. Sugar in the colon also messes up the osmotic
pressure causing water retention, which gives the person a bloated feeling or
even diarrhea.
-Some cultures can digest lactose in adulthood, some cannot.
-Lactose intolerant people can drink up to about 500 mL of milk a day without
severe symptoms.
-People allergic to milk are allergic to the milk protein.
VITAMIN D: (D3) This vitamin is converted in the kidneys into a hormone
(calcitonin) that regulates the absorption of calcium by the small intestines and
kidneys and its incorporation in bone tissue.
-The lack of vitamin D leads to rickets, or softening of the bones.
This vitamin is fat-soluble, not water-soluble.
Milk is fortified with vitamin D to prevent rickets. Adult rickets is called
osteomalacia.
A "vitamin" by definition is a substance regularly required by the body in small
amounts but which the body cannot make and is, therefore, required to be
supplied in the daily diet. Technically the molecular species classified as vitamin
D is not really a vitamin because it can be produced by exposure of the skin to
sunlight. However, for nutritional and public health reasons, vitamin D 3 continues
to be classified officially as a vitamin.
CREAM: The word cream comes from the Greek “chriein”, which means, “to
anoint”. Cream is a form of milk in which the fat globules have become more
concentrated than usual.
Light cream is between 18-30% butterfat
Light whipping cream is between 30-36% butterfat
Heavy whipping cream is between 36-40% butterfat
Whole milk is between 3.2-4.0 % butterfat
Half-and-half is between milk and cream and must be at least 10.5% butterfat
Cream can be whipped into stable foam.
Cream tends not to curdle because it has very few proteins in it.
Reference: On Food and Cooking by Harold McGee, Scribner, NY, 1984.