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  • Writer's pictureAshleigh Richmond

Formula Preparation Guidelines

Updated: Sep 25, 2023

National and international recommendations for mixing formula differ slightly, and product labels contain a plethora of instructions, adding to the confusion surrounding formula preparation. There are some basic steps that all parents should take in order to mitigate possible health issues associated with formula preparation.

safely feeding formula powder

Cronobacter is a rare but serious infection that can be caused by germs in powdered infant formula. In most cases, it is safe to mix powdered infant formula following manufacturer’s instructions. But if your baby is very young (younger than 3 months old), was born prematurely, or has a weakened immune system, you may want to take extra precautions to protect against Cronobacter.

Powdered formula preparation instructions to help protect your baby from Cronobacter:

  1. Examine formula can stamp to ensure it is not part of a recall, and that it has not expired (once a can of powder formula has been opened, it is good for 30 days). It's a good idea to write the date you open it on the can.

  2. Practice excellent hygiene habits (wash hands for at least 20 seconds, clean and sterilize countertops where formula will be prepared, clean the top of the formula can prior to opening it, sterilize bottles and nipples).

  3. Heat clean water to 158 ̊F/70 ̊C. Be aware that homes built in the US prior to 1986, often used lead in the pipes. Boiling water that contains led concentrates the levels of lead. Any amount of lead is dangerous. If the home tap water is not safe, bottled water should be used. Parents who do not have a thermometer, can bring the water to a boil (water boils at 212 ̊F) and then let it cool no more than 30 minutes. This process will ensure the water is hot enough to kill the bacteria in the powder.

  4. Pour the hot water into the clean bottle.

  5. Add the powder formula right away. Follow the manufacturers direction regarding loose or packed scoops of powder. For level scoops, use a clean straight edge to ensure correct measurements. Never try to use 1⁄2 a scoop.

  6. Once the formula is mixed, cool it quickly for feeding. Prepared formula can be submerged in cold water to placed under cold, running water.

  7. Prepared formula that is not refrigerated must be used within 2 hours. Once feeding begins, the bottle must be discarded after one hour. Formula that is prepared, can be refrigerated up to 24 hours.

It is more convenient for formula-feeding families to make several bottles at one time and refrigerate them. They can be re-heated prior to feeding.

Parents using ready-made formula, only need to sterilize the nipple they are connecting to the ready- made bottles. If transferring the ready-made formula into a bottle, the bottle and nipple should be sterilized. Liquid formula is easier to use, but often costs much more and might not be available.

Parents should educate themselves regarding donor human milk and informal milk sharing. In emergency situation and with formula shortages, these resources can be life-saving.


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