The principle of ultrafiltration (UF) is filtration of solutions or
suspensions under pressure through a semipermeable membrane.
The membrane has pores that allow the solvent and small molecules
to pass through and the larger molecules to be retained.
There cannot be any serious doubt about the superiority of breast
milk in the nutrition of the healthy term infant (1-3). However, it
is frequently impossible for preterm infants and very-low-birthweight
infants to be nourished with their own mothers' milk.
Since the turn of the century, the antibacterial activity of milk
has attracted the attention of scientists in human and veterinary
Current recommendations, both in Europe and the United States,
emphasize breast feeding as the regimen of choice for the healthy
term infant (1,2).
Milk is a complex fluid containing cells and membranes as well
as a wide variety of soluble and insoluble components. Among the
latter are the classical nutrients such as proteins and lipids (1).
Although the main theme of this volume includes the composition
of human milk and the specific requirements for different components
of milk for infant nutrition, our interest in milk proteins has
been generated for rather different reasons.
It is well known that human milk will protect infants against
various gastrointestinal infections (1,2). Colostrum and milk contain
several components that are thought to contribute to this protective
This work was undertaken to extend our knowledge of the heat
stability of some of the proteins in human milk believed to serve
protective functions in normal human infants.
Efforts to develop experimentally based feeding protocols using
human milk for very-low-birth-weight (VLBW) infantr reveal two
Although milk banks have been in existence for more than 50
years (1), the past decade has seen a resurgence of interest in their
functions and systems of operation.
Albumin, in human milk protein
powder, 59, 60
Alkaline phosphatase, 97, 98
Amino acid levels
free, whole-blood, 161, 165,
Amylase, in human milk protein
to E. coli, effect of heat on,
The 17 milk banks in France collect about 90,000 liters of milk
per year (1). Since 1947, the heat treatment employed has been
tyndalization (65°C for 20 min carried out three times) in accordance
with the 1954 Department of Health Report (2).
Several epidemiologic studies have indicated that breast feeding
protects infants from bacterial and viral infections and from allergy
(1-6). Recent prospective studies performed by Chandra (7) in an
industrialized country and in a developing one confirm that in both
countries, breast-fed infants have lower morbidity than those artificially
It has been suggested that the growth of very-low-birth-weight
infants fed human milk may be restricted by protein (1) and energy
This chapter concerns some of the observed metabolic effects of
varying the protein and fat content of human milk.
The best food for low-birth-weight (LBW) infants remains controversial.
Because of its immunological properties and nutritional
qualities, human milk is considered the superior food for all neonates.
A principal effect of juxtaposing presentations of in vitro biochemical
experiments and clinical studies was disclosure of the gap
between in vitro observation and the demonstration of a clinical