Sterilising baby equipment, and baby bottles in particular, dates back to the late 17th and early 18th century when there was a very high infant mortality rate for babies who were fed with cow’s milk. However, archeological findings indicate that feeding infants cow’s or goat’s milk has been a practice used for thousands of years. Substituting animal milk for human breast milk was most often the practice when the mother died or was too sick to feed her baby and a wet nurse was not available.

The industrial revolution, in the late 1800s and early 1900s, brought an increase in infants who were bottle fed because women had to leave their babies for extended periods of time in order to go to work in the factories. Meanwhile, science was making strides in improving the safety of the bottle-feeding practice. In 1867, a German scientist developed the first baby formula; and in the late 1800s, when the practice of pasteurizing milk was perfected, bottle feeding also increased as mothers could rely on sterile condensed milk.

Although the milk itself was sterile, public water supplies contained contaminants that were harmful to babies. So, the water used to wash the feeding supplies introduced contaminants into the baby’s bottle any way. And, if a dry formula was used the water used to mix it contained a host of bacteria. Common practice was to mix a batch of formula and let it sit out until needed. Unfortunately, since the water was contaminated, bacteria would breed in the unrefrigerated bottles of formula.

When physicians and parents became aware of the dangers of using public water supplies, it becoming common to sterilise the water, bottles and nipples before using them to feed infants and babies. Feeding equipment was typically sterilised by boiling in water for 10 to 15 minutes to kill any bacteria or other impurities.

By the 1950s, city water supplies were being carefully monitored and the water became safe to use without fear of bacterial contamination. Despite scientific studies done in the 1950s that indicated that infants could be fed safely using clean–but not sterilised–bottles and nipples, and the formula could be safely mixed with tap water, the practice of sterilisation of baby feeding supplies was firmly ingrained as a necessary practice.

Although submersing feeding supplies into boiling water is still probably the most popular option, technology and scientific advancements have led to the development of a variety of sterilisation devices. The most common are electric and microwave sterilisers. The electric steam steriliser has space inside for the bottles, nipples, rings, and caps. It works by filling it with water and turning it on. Within a few minutes the feeding equipment is sterilised and remains that way for quite some time as long as the device isn’t opened. Microwave steam sterilisers are virtually the same, except for instead of plugging them in, they are placed into the microwave for a set amount of time. One thing to keep in mind with this type of steriliser is that all of the feeding paraphanalia to be sterilised needs to be microwave safe.

There are also other types of sterilisers available, including disposable sterilising bags to which a sterilisation tablet and water are added. This sterilisation method is very convenient for traveling since it’s not necessary to take a sanitizing unit with you. Cold water sterilisers consist of a container, holding rack and a lid. To use, it is filled with a sterilising solution and the feeding items are completely immersed.

While a number of devices have been developed over the years to make sterilisation easier, heat is still the method of choice just as it was in the early 1900s. The difference is that in addition to submersing bottles and other baby supplies in boiling water, we can now also harness the power of steam to accomplish the same result.