Colostrum, often called “liquid gold,” is the initial milk produced by the body, typically beginning in late pregnancy and continuing for the first few days after birth. This unique substance is exceptionally rich in antibodies, growth factors, proteins, and essential nutrients. It plays a crucial role in providing a protective foundation for newborns, supporting their early health and development. Understanding how to properly preserve this valuable substance is important for parents.
What is Colostrum and Why Freeze It?
Colostrum acts as a natural defense system, offering significant advantages for a newborn’s well-being. It is packed with white blood cells and antibodies, such as immunoglobulin A, which help strengthen the baby’s developing immune system against infections. This concentrated milk also aids in establishing a healthy gut by coating the intestines and promotes the clearing of meconium, the baby’s first stool, which can help reduce the risk of jaundice. Its low-fat, high-protein composition makes it easily digestible for a new infant’s delicate system.
Parents might choose to express and freeze colostrum for several reasons. This practice can be beneficial if there are concerns about the baby’s ability to latch immediately after birth or in anticipation of a temporary low milk supply. Freezing colostrum also creates an emergency supply for premature infants, babies with low birth weight, or those who may require early supplementation, such as infants whose mothers have gestational diabetes, to help stabilize blood sugar levels. Collecting colostrum as early as 37 weeks of pregnancy allows for preparation.
Recommended Freezing Durations
The duration colostrum can be safely stored in a freezer depends on the type of freezer and its consistent temperature. For optimal quality, colostrum stored in a deep freezer, which maintains a consistent temperature of 0°F (-18°C) or colder, is recommended for up to 6 months. While some guidelines suggest it can be kept for up to 12 months in a deep freezer, using it within 6 months is preferred to preserve its unique properties.
For freezer compartments within a refrigerator, colostrum can be stored for a shorter period. These freezers often maintain less consistent temperatures than standalone deep freezers. Colostrum stored in these compartments is recommended for use within 3 to 6 months.
Maintaining a stable freezer temperature is important for preserving the quality of colostrum over time. It is advisable to store colostrum at the back of the freezer rather than in the door, as the temperature in the door fluctuates more frequently with opening and closing. Although freezing helps preserve colostrum, some degradation of nutrient content or protective components may occur with extended storage.
Best Practices for Freezing and Thawing
Proper handling of colostrum before and after freezing helps maintain its quality and safety. When preparing colostrum for freezing, use sterile syringes or clean, food-grade containers made of BPA-free plastic or glass with tight-fitting lids. Freezing colostrum in small, usable portions (e.g., 1-5 ml or 2-4 ounces) helps avoid waste, and remember to leave about an inch of space at the top for expansion as it freezes. Each container should be clearly labeled with the date and time of expression.
Once expressed, it is best to freeze colostrum as soon as possible if it won’t be used within a few days, which helps prevent bacterial growth and preserves its quality. When adding freshly expressed colostrum to an already frozen supply, ensure the new milk is first chilled to the same temperature.
Safe thawing methods are essential to protect the integrity of the colostrum. The preferred method is to thaw it slowly in the refrigerator overnight. Alternatively, colostrum can be thawed more quickly by holding the container under cool or lukewarm running water, or by placing it in a bowl of warm water. Never use a microwave to thaw or warm colostrum, as this can destroy beneficial nutrients and create dangerous hot spots. Thawed colostrum should never be refrozen.
Once thawed in the refrigerator, colostrum should be used within 24 hours of being fully thawed. If colostrum is brought to room temperature or warmed, it should be used within 1 to 2 hours. Any thawed colostrum remaining after these recommended timeframes should be discarded. If a baby has partially consumed a bottle of thawed colostrum, any leftover milk in that bottle should be discarded after one to two hours to ensure safety.