digest milk slows down, then completely disappears. In western cultures children

continue to drink milk after weaned, so their bodies keep producing lactase. There

are also genetic differences in adult lactase production among different peoples.

In people whose bodies don’t produce enough lactase, drinking milk causes

digestive problems. They have lactose intolerance.

In fermented milk and processed milk products, the fermenting bacteria use up the

lactose as their food—people with lactose intolerance have no digestive problems

with these low or no-lactose dairy foods. They can also drink acidophilus milk to

reduce digestive difficulties. Acidophilus is a bacteria (Lactobacillus acidophilus)

that processors add to the milk that can digest lactose. This bacteria stays inactive

in cold milk, but wakes up when you get them in your warm body. It doesn’t

change the flavor of the milk. The live culture in yogurt also digest lactose. Now

enzymes are available that people with lactose intolerance can take that digest

lactose for them.

Milk and its Products

Milk

Pasteurizing milk has been an industry-wide standard in the U.S. since the 1940s.

Pasteurized milk offers many advantages, even though the full, rich, sturdy flavor of fresh raw

milk suffers. It is against the law in almost all of the U.S. to sell raw milk or transport it across

state lines. The milk producers must pasteurize, ultra-pasteurize or ultra-high-temperature

process milk before they sell it. Raw milk is high in bacteria that reduce its useable shelflife to

half or a third compared to pasteurized milk. Even if it is free of bacteria, the active enzymes in

raw milk would rapidly spoil it and produce sharp off flavors.

To pasteurize milk, the processor heats it slowly without boiling (boiled milk develops an

unnatural cooked flavor). It takes 15 seconds to pasteurize milk at 160°F (72°C), 30 minutes at

44°F (63°C). Pasteurization destroys all pathogenic bacteria, yeasts and molds. But it destroys

only 95 to 99 percent of nonpathogenic bacteria, so it is not as sterile as when it left the cow’s

udder. In practice that means the bacteria count is harmlessly low, but if the kids leave the carton

out on the kitchen counter overnight, those few bacteria grow into a real problem. Pasteurization

also deactivates those milk enzymes that cause rapid spoiling.

Homogenization is another process all U.S. milk undergoes to keep the tiny fat particles

from congregating at the surface (they are the lightest, so slowly they rise), that would turn into

heavy cream. The homogenizing process is simple. The processor pumps the milk through tiny

orifices under high pressure to reduce the size of the fat globule from very small to microscopic

(

less than 2 millimicrons). This makes it physically impossible for them to clump together and

rise to the surface.

A relatively new process allows you to store milk without refrigerating it. In ultra-

pasteurization, they flash-heat milk to 280°F (139°C) for 2 to 4 seconds. Ultrahigh-temperature

UHT) processing is the same, but the processor also packages the milk in sterilized, sealed

(

paper cartons for a shelflife of many months without refrigeration. It comes in handy for

Serious Kitchen Play