When full screening is not available, donor health status is unknown, or to reduce the potential risks of exposure to HIV and/or other pathogens, breastmilk can be pasteurized at home.
- Holder pasteurization
Holder pasteurization is considered the standard for human and cow’s milk pasteurization. It has been shown to inactivate pathogens while maintaining adequate nutritious properties. However, given its longer time-temperature curves, this method damages more of the antimicrobial factors of breastmilk than would flash pasteurization.
This method of pasteurization can be done by parents or caregivers on the stove top, or with a home pasteurizer kit for human milk. Some mothers may decide they want to buy commercial grade pasteurizers which are also available.
For an explanation on how to perform Holder on the stove top, please go here.
- Flash-heating (FH)
Flash-heating is a low-tech method of pasteurizing breastmilk that was developed for HIV postitive mothers in developing countries who had no safe or affordable alternatives for feeding their infants.1
For an explanation on how to perform the Flash-heat method of pasteurization, please go here.
For more information on the different pasteurization methods see this section.
Cooling down heat-treated milk
Cooked foods have a ‘danger zone,’ a temperature range from 60ºC/140ºF to 4ºC/39ºF where bacteria like to grow. It is therefore important to cool milk down quickly after it has been heated. Cooling the container in ice water is the quickest way to cool milk. Depending on the amount of milk, cooling it in the refrigerator is generally not recommended as the milk will cool unevenly, leaving some milk too warm for too long. Please know that not all glass is suited for heating and rapid cooling.
Reusing heat-treated milk In this study, the researchers discuss that after cooling “flash-heat was successful in completely eliminating bacteria in the majority of samples, and prevented substantial growth for up to 8 h when stored at room temperature.”
To date, the safety of reheating previously heat-treated milk has not, to our knowledge, been studied. It should be noted that most literature speaks in terms of heating expressed milk for feeding but that mothers generally warm the (thawed) milk under running warm water or set it in a container in warm water for a short while to get the chill out of it. Gently warming should not be considered heat-treating. For optimal properties of breastmilk, reheating (warming) milk should not be done directly in a pan on the stove top nor in a container set in boiling water on the stove top (which would be heat-treating it unnecessarily).
Heat-treated milk can possibly be refrigerated or frozen following common food safety protocols. We suggest, however, that after a first feeding, milk that was heat-treated not be refrigerated and reheated again as anti-bacteriological properties can decline with increased handling.
- Please see ‘Human Immunodeficiency Virus (HIV)’ and ‘HIV and the global context of infant feeding’ for more information. [↩]
- See: ‘Heat Treatment of Expressed Breast Milk Is a Feasible Option for Feeding HIV-Exposed, Uninfected Children after 6 Months of Age in Rural Zimbabwe’, ‘Flash-Heat Inactivation of HIV-1 in Human Milk’, ‘Inactivation of Cell-Associated and Cell-Free HIV-1 by Flash-Heat Treatment of Breast Milk’ [↩]