The immune system is the one in charge of defending our bodies from any infection. Since day one, breast milk or formula helps your little one start to develop this system, and the process continues until they are one year old. That’s why it is important to keep in mind the precautions and recommendations of how to prepare, sterilize, and preserve the milk that you use to feed your baby.

First, it’s very important to clean the area where you prepare your baby’s bottle. Appropriate sterilization is vital to avoid the risk of microbial contamination and the early spoiling of breast milk or formula. Clean and disinfect all surfaces that are in touch with the bottle and other products that are going to be in contact with your baby. Always wash your hands with soap and water before preparing anything your little one will ingest.

Once you prepare the bottle, you should use it immediately or properly store it. We recommend using the formula within the first two hours after the preparation. This is due to the fact that the prepared formula may spoil if it’s left more than two hours at room temperature.

Also, it’s recommended you use the prepared formula within one hour after starting to feed your baby. The combination of saliva and formula can favor the production of bacteria, so it’s best to use it during this window of time or throw out the formula that your baby did not finish. Also note that if you prepare the bottle and use it later, the formula must be kept in a cool and closed space, away from vehicles, the garage, or outdoor spaces.

If you don’t use the prepared formula within the first two hours, you should refrigerate it immediately. The refrigerator needs to be at a maximum temperature of 5 °C (41 °F) to prevent or delay bacterial growth. We also recommend that before storing a bottle, you put it under cold water. As the last recommendation, make sure to use the formula within the next 24 hours after refrigerating it.

If you correctly stored it and the recommended time hasn’t passed, you don’t need to reheat the milk or formula before feeding your little one. However, if you decide to do it, warm the bottle under warm running water. You shouldn’t use the microwave since it heats the food unevenly and your baby might burn their mouth or throat because of this. Once you heat the bottle, check the temperature putting some drops on the back of your hand.

It’s important to follow these recommendations to properly store and preserve baby formula. That way, you’ll avoid any risk of consuming spoiled food, but, most importantly, you’ll strengthen your baby’s immune system.


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