Both milk and soy formulas are available in powder, liquid concentrate, or ready-to-feed forms. The choice should depend on whatever the parents find convenient and can afford.
Whatever form is chosen, proper preparation and refrigeration are essential. Opened cans of ready-to-feed and liquid concentrate must be refrigerated and used within the time specified on the can. Once the powder is mixed with water, it should also be refrigerated if it is not used right away. The exact amounts of water recommended on the label must be used. Under-diluted formula can cause problems for the infant's organs and digestive system. Over-diluted formula will not provide adequate nutrition, and the baby may fail to thrive and grow.
Until recently, the American Academy of Pediatrics felt that municipal water supplies were safe enough without boiling the water before mixing with the formula. But because of the contamination of Milwaukee's water with the parasite Cryptosporidium in 1993, "the whole business of boiling water has come up again," says Klish. "The academy is now again recommending boiling water for infant formulas."
Klish advises heating the water until it reaches a rolling boil, continue to boil for one to two minutes, and then let it cool. "That should take care of all the bacteria and parasites that might be in the water," he explains.
The American Academy of Pediatrics does not have any recommendations about bottled water. Klish says bottled water is fine, but it still needs to be boiled. "There's no reason to think that bottled water is any safer than city water," he says.
Bottled water must meet specific FDA quality standards for contaminants. These are set in response to requirements that the Environmental Protection Agency has established for tap water.
A new regulation published in the Nov. 13, 1995, Federal Register sets standard definitions for different types of bottled waters, helping resolve possible confusion about what different terms mean.
The regulation also requires accurate labeling of bottled waters marketed for infants. If a product is labeled "sterile," it must be processed to meet FDA's requirements for commercial sterility. Otherwise, the labeling must indicate that it is not sterile and should be used as directed by a physician or according to infant formula preparation instructions.
What about sterilizing the bottles and nipples? "Dishwashers tend to sterilize bottles and nipples fairly well," says Klish. They can also be sterilized by placing in a pan of boiling water for five minutes.
Warming the formula before feeding isn't necessary for proper nutrition, but most infants prefer the formula at least at room temperature. The best way to warm a bottle of formula is by placing the bottle in a pot of water and heating the pot on the stove.
