Storing and Using Expressed Milk

Learning how to store and use expressed milk will ensure you reap the benefits of expressing. Following simple guidelines will ensure you never have to worry whether breastmilk is still usable or not.

Storing Your Expressed Milk
Guidelines for Storing Milk
Transporting Your Milk
Thawing and Heating Expressed Milk

Storing Your Expressed Milk

You should handle milk with care but not too much fuss. The same immune properties in your milk that protect your baby also protect the milk from bacteria while it sits on the refrigerator's shelf.

Freezing destroys some of the immune properties in human milk, so it's best if your baby is given fresh milk: milk that has been expressed and refrigerated. Make sure you label each container with the date you have expressed it, so you can use the oldest milk first and avoid wasting any.

There is different research, which states different things about the loss of milk properties with different types of storing plastic bags, glass or plastic hard containers. If your baby is getting a lot of his nourishment directly at the breast, you don't need to be as concerned about nutrient loss through freezing or contact with storage containers. Hard sided containers provide the best protection for nutrients and immunities, and sterisation is no longer considered necessary. However, convenience is a factor to consider, as your time is a valuable part of this equation. Here are some factors to consider:

• Plastic bags take up less room in the freezer and cooler you may be using to transport milk.
  
• Plastic bags are one-use items, so there is no washing up involved. You'll save time and have one fewer chore to worry about.
  
• Be sure to store your milk in "freezer" storage bags, which are less likely to leak.
  
• Plastic bags are associated with a higher incidence of sour-tasting or soapy-tasting (but not spoiled) milk.
  
• Plastic bags can be purchased that fit directly onto a pump. They have built in closures and are easier to seal.
  
• Bags containing human milk should be placed inside another container in the refrigerator or freezer. This makes for better protection and easier handling.
  
• If you lay the bags down in a container in the freezer, you'll get flatter packages that will thaw more quickly. (But be sure they are sealed well, or you'll end up with a leaky mess).
  
• Always leave some space at the top of the bag or container for expansion.

Guidelines for Storing Milk

The table below is a quick guide to how long breastmilk can be stored, depending on where you store it.

To Save or to Dump Expressed Milk

The table below lays out some simple rules of thumb when you are in doubt as to what you should do with breastmilk in some situations.

Transporting Your Milk

Research shows that bacteria do not grow readily in human milk and that it can be kept safely at room temperature or 4-6 hours (or more—see box above). You don’t need to worry if you can’t rush your milk to the refrigerator right after you express. But it still makes sense to refrigerate the milk as soon as possible and to keep it cool when taking it home or to the caregiver’s place. An insulated container works well, too.

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Thawing and Heating Stored Milk

Heat can destroy human milk’s enzymes, immune properties and other valuable components, so it requires gentle care before it is served to baby. Follow these guidelines:

• Defrost milk by holding the container under warm running water. Or, for a larger container, place it in a bowl of warm water. After the water cools, replace it with more warm water until the milk is thawed and warmed to body temperature.
  
• Do not heat expressed milk on the cooker or microwave. It’s too easy to overheat or heat unevenly. Do not boil it.
  
• Human milk, like any milk that is not processed tends to separate when stored. The cream rises to the top. Swirl the bottle gently to mix the layers.
  
• Human milk has a thin, bluish look to it, quite different from either cow’s milk or infant formula. Your baby’s caregiver may need reassuring that the colour is normal.
  
• On rare occasions mothers report that their milk “spoils” or has a soapy smell within hours and that baby rejects it even when it is stored in a hard container. This is thought to be caused by higher levels of enzymes (especially lipase) in some mother’s milk. What happens is that the fat cells are being prematurely broken down by the lipase, causing a strong odour. In such cases, scalding the milk (just short of boiling) seems to stop the process. Do this only if the baby repeatedly refuses the milk, since heat destroys valuable enzymes. Note that sometimes the baby may just need to get used to the taste.