The Best Bottle Sterilizer
A bottle sterilizer isn’t a mandatory purchase. In fact, we feel comfortable saying you don’t need one! Our research showed even experts disagree—some say bottles should be sterilized before the first use, others say they should be sterilized in the baby’s first six months, and others say not to bother at all. If your doctor recommends your baby’s bottles be sterilized or you have your heart set on sterilized bottles, we found the best all-around electric bottle sterilizer is Munchkin Steam Guard Electric Sterilizer. This sterilizer is easy to use, reliable, inexpensive, lightweight, durable and handles bottles of all shapes and sizes.
This article was originally published in March 2015. It has been updated to reflect current products and additional recommendations in October 2017.
Ask a set of parents if they sterilized their baby’s bottles, and you’ll get an array of answers. The ones who did are quick to defend their decision, and the ones who didn’t wonder if they should have. Even though the American Academy of Pediatrics says “sterilizing water, bottles, and artificial nipples is not necessary if the water supply is safe and if refrigeration is available,” there’s still a lot of debate over how to do it and for how long.
Older generations insist that putting bottles in a pot of boiling water is the best way to go. Today’s parents may choose an electric sterilizer, a microwave sterilizer, a sterilizer bag, or just use the dishwasher. There are even concerns over the possible dangers of heating plastic bottles and the release of Bisphenol A (BPA).
We scrutinized six electric bottle sterilizers and four microwave sterilizers over the course of more than 20 hours after narrowing them down from a pool of about 15. We poured over online reviews, considered opinions from experts, put the products into real-world testing, and asked parents and medical professionals for their opinions. We also spoke to experts about the need for bottle sterilizers in the first place, and how they should work.
who should buy A Bottle Sterilizer?
Parents with newborns and babies in the bottle-feeding years are the best candidates for bottle sterilizers. You should definitely buy a bottle sterilizer if you live in an area with a questionable water source, have unreliable access to a clean environment, or if you don’t want to use the boiling-water method. In some cases, special-needs and premature babies are also candidates for bottle sterilization because they may be susceptible to infection-causing germs. Parents should always follow their physician’s recommendations regarding sterilization, but many doctors tend to be cautious when it comes to fragile newborns. Even with that, sterilizing often doesn’t go on for more than a couple of months.
Bottle sterilizers are designed to be used for bottles and accessory parts including nipples. But if you consider that there’s nothing special about the shape of a bottle, sterilizers can have life well beyond the bottle years. They can be used for breast-pump parts, sippy cups, toddler plates and home-nebulizer equipment.
What makes a good bottle sterilizer?
Before the late 1890s, nearly one third of all infants who were bottle fed died in before they were one, leaving medical science baffled about the cause. It wasn’t until microbiologists of the time developed the germ theory that cleanliness and sterilization became the norm. Even with this knowledge, many parents still made formula in large batches and left them unrefrigerated. (Or sadly were sold “swill milk” by irresponsible dairies). This, along with questionable water supplies, led to bacterial contamination. That’s when the boiling method of sterilization became commonplace: bottles were placed in a pot of boiling water for 15 minutes or more.
By the 1950s, studies showed that American parents knew enough about aseptic techniques and the nation’s water supply was so sanitary that bottles could be used safely if they were clean with hot tap water and soap. But by then, sterilization had become so ingrained in the American psyche that it was difficult to let go of the old ways.
“No one recommends ‘sterilizing’ bottles any more. Processes traditionally used at home don’t sterilize anyway, and baby’s mouths are not sterile,” said Dr. Roy Benaroch, a Georgia pediatrician, author and blogger. “Water that’s safe enough for adults to drink is safe enough for babies to drink.”
Even as the American Academy of Pediatrics currently recommends that bottles and nipples only be cleaned with soap and hot water (or run through a dishwasher), some parents and pediatricians are hanging on to the old rules. The topic has become so polarizing that many doctors, while saying it’s not necessary to sterilize, recommend that parents go with their gut because it can’t hurt.
When it comes to sterilizing, it’s also important to recognize the role of the common plastic additive Bisphenol A (BPA), an estrogen-mimicking industrial chemical. In 2012, the U.S. Food and Drug Administration banned the chemical in baby bottles and cups because of a possible link to developmental disorders. The FDA recommends never putting hot or boiling liquid into BPA-containing bottles because the heat may cause the BPA to leach into the liquid. At the same time, it’s probably a wise move to use a BPA-free microwave sterilizer. To be on the safe side, never use plastic bottles or a microwave sterilizer made before 2012.
The topic has become so polarizing that many doctors, while saying it’s not necessary to sterilize, recommend that parents go with their gut because it can’t hurt.
If you’re set on sterilizing and are confident that your bottles are BPA free, it’s time to look to either a microwave or electric sterilizer. Luckily, most aren’t that expensive.
On the top of the scale, an electric sterilizer can cost more than $100. Most, however, are in the $30 to $50 range. Some parents like the electric models because they’re sturdy and self-contained, while others swear by the microwave design for the convenience factor. Of course, you could always use the old pot-of-boiling-water method (put the bottles in a large covered pot of boiling water for at least 15 minutes), but it’s fraught with problems. That includes the time it takes to boil a large pot of water (what new mom has that kind of time?) and the chance for a serious accident.
Today, there are at least 15 electric and microwave models on the market. Like anything else, the more expensive the model, the more bells and whistles. But we’ve found more features don’t typically make a better product.
The few things that are required for bottles to be sterilized using the steam method (there are other methods that we’ll get to later) is high heat, moisture and time. Moist heat over 212 degrees kills most bacteria within minutes. Most, if not all, bottle sterilizers, either electric or microwave, are made to achieve this temperature.
Best Electric Sterilizer Features
The best electric bottle sterilizers have the following features:
- Compact—The perfect bottle sterilizer is compact enough to take up only a small amount of counter space but roomy enough to fit all sizes of baby bottles. For parents with limited counter space, this is especially important because the sterilizer will likely stay on a countertop for the duration of use. At the same time, the compact sterilizer must be big enough to handle some of the wide and tall bottles on the market (such as Dr. Brown’s Natural Flow and the Munchkin Latch.) If you have to lay your bottles in the sterilizer, water could collect in them and defeat the purpose of what you’re trying to accomplish.
- Ease of use—Some of the more popular sterilizer brands come with several parts that must be put together and taken apart for each use. This complicates the process because there’s a risk of breaking or losing an important component. Also, what parent wants to be fumbling with assembly at 4 a.m.? The best product is simplistic, with only a few moving pieces and parts.
- Reasonable price—Electric bottle sterilizers prices range from the astronomical (Wabi Baby retails for about $140) to reasonable (Munchkin Steam Guard Electric Sterilizer retails for less than $20). The average price for an electric sterilizers is about $50. No parent should pay more than $50 for a bottle sterilizer. Remember, it’s just a simple machine that creates steam from boiling water. (And one that, frankly, we’re not entirely sure you must have.)
- Quick cycling — For most machines, the amount of time it takes to sterilize is directly related to the amount of water put in the machine. The more water, the longer the cycle. There’s also a (wisely) recommended period of time that the bottles should sit in the machine after the cycle is complete. (Forget to do this and you could wind up with a nasty steam burn.) All that said, most machines have automatic shut-offs despite the amount of water. Some machines take up to 12 minutes to cycle through, while other can take as little as 6 minutes. When you add the 10 minutes rest time after the cycle, the total time could be as much as 22 minutes for some machines. That’s 22 minutes of torture for any parent listening to a hungry, crying baby.
- Versatile — Any bottle sterilizer should serve as a multi-function machine. In the infant years, it should hold bottles, nipples, caps and the like. It should also hold breast-pump parts including tubes and breastshields. Later, it should be able to hold toddler tableware, including plastic spoons and forks. It can also be used to sterilize nebulizer parts.
Smaller details of features, like an end-of-cycle beep and cool-to-touch body, differentiates good sterilizers from great ones. However, these are just wish-list items and aren’t required for the top model. Features like tongs, especially the ones we found included with most brands, are typically useless.
Best Microwave Sterilizer Features
- Fit—While microwave sterilizers don’t create storage hassles like their electric counterparts, they have their own set of challenges. They need to be big enough to hold a variety of bottles and accessories, but small enough to fit into most microwaves. With a wide variety of microwave sizes on the market, this makes finding the perfect fit challenging. For some parents, that might mean trial and error (read: more cost and hassle).
- Durability—The inherent problem with microwaving plastic is that it becomes soft and flexible. This is a problem when you’re removing a blazing hot sterilizer with steaming water and hot bottles from a microwave. According to the Consumer Products Safety Commission, sterilizers (in the same category with bottle warmers) caused an estimated 1,800 injuries in 2012 that required emergency room treatment. The best product in this category will be sturdy and strong.
- Ease of Use—A good microwave sterilizer will not have too many pieces and parts to assemble. Again, no one wants to have to assemble a bottle sterilizer with a hungry baby on the prowl.
- Reasonable price—On average, a microwave sterilizer should cost about $25. It’s a simple product that performs the most basic of tasks—boiling water.
How we tested
After thoroughly researching all of the possible bottle sterilizers on the market, reading countless reviews and talking to medical professionals, we narrowed the selection down to five electric and four microwave sterilizer designs based on the previously determined parameters. Each product was used according to the manufacturer’s instructions included with the product. Each used the manufacturer’s predetermined amount of tap water (the test water was hard) with new baby bottles and accessories.
They were all put to the test using the following bottles:
- Munchkin Latch (stage 1) – 4 and 8 oz
- Dr. Brown’s Natural Flow standard (level 1 nipple)- 8 oz
- Dr. Brown’s Natural Flow wide neck (level 1 nipple) – 8 oz
- Hospital-issue Volu-Feed disposable nursers – 2 oz
- Hospital-issue Emfamil standard-flow soft nipples
While the electric sterilizers were working, we jiggled them, touched them while hot (not recommended) and kept an eagle eye to see how and where the steam escaped. Once completed, we noted how much water was left in each and the ease of drying and storage.
For the microwave variety, we moved them in and out of different microwave sizes to determine the fit and the safety of moving scalding hot water. The main microwave used was 1200 watts with 1.3 cubic feet of space. We tried to bend the hot sterilizers to see how malleable the plastic became and placed them in cold water to see the reaction. We noted the amount and areas of steam escape and the fit of the components.
- Dimensions: 12 x 10 x 10 inches
- Weight: 3.9 pounds
- Capacity: up to 9 bottles
- Cycle Time: 6 minutes
After weeks of research and testing, we are confident to report that Munchkin Steam Guard Electric Sterilizer is the best on the market for most parents because it is easy to use, inexpensive, reliable, lightweight, handles bottles of all shapes and sizes, and is uncomplicated. The lid had snap closures on each side for an added layer of protection from an accidental spill.
The Munchkin Steam Guard Electric does what all bottle sterilizer models do: it heats water to create steam that kills microorganisms. But it does it without any unnecessary complications. It’s a very basic model that is flexible enough to fit bottles from most manufacturers and has enough space to handle all bottle accessories (like nipples and caps) as well as other items that might need to be sterilized (like toddler spoons or pacifiers). The multi-level rack ensures that bottles of all sizes fit, and the safety locks prevent the machine from popping open unexpectedly. The large capacity allows up to 9 bottles at a time, which is a three- or four-bottle capacity larger than others.
While you won’t find it to be particularly flashy, it gets the job done efficiently and effectively. What more do you need? At a relatively low cost, it’s priced right, too; it’s cheaper than most electric bottle sterilizers.
It might have been nice to have a drying feature, but most reasonably priced sterilizers don’t have that at this point. It would also be nice if the bottle holder had indentations so the bottles wouldn’t be so wobbly on the holder and bigger tongs for the parent who might want to use them (the ones included are pretty worthless).
Who else likes it?
Bottle sterilizers are not the kind of baby gear that get a lot of consideration—not like play yards or strollers, anyway—and Munchkin isn’t a brand that typically garners a lot of attention. But when it comes to the Steam Guard, its fans swear by it. They loved the reasonable price, versatility and ease of cleaning.
Amazon.com customers said it was sturdy, reliable and reasonably priced. “It was not a massive time consumer and I was pleased with the outcome. There is nothing overwhelming about its setup for first time parents (yay!). And with the time saved, maybe a little rest might be possible,” one Amazon customer said. Others lauded its versatility (it’s compatible with lots of brands of bottles) and the reasonable price.
The best Microwave Sterilizer
Munchkin Steam Guard Microwave Sterilizer
Our choice for the best microwave-based design is also from Munchkin. The Steam Guard Microwave is inexpensive, lightweight, sturdy and handles a variety of bottle shapes and sizes. The easy-to-snap side closures give an added level of safety from spilling steaming hot water from the countertop to microwave.
The Munchkin Microwave is easy to use: all you do is put in 7 ounces of water, assemble the bottles, pop on the lid and microwave for a set period. Even better, it fits bottles from a variety of brands. Yes, I’m sure the manufacturer would love for you to use only Munchkin products in it. But what parent hasn’t gone through a billion different brands of bottle before figuring out which is best? Chances are the bottles you start out with from your baby registry aren’t the ones you’ll end up with at 6 months old. The microwave-based Steam Guard is compact enough to fit into most ovens, but roomy enough to fit breast-pump and other accessories.
The Munchkin Microwave truly is a bare-bones model, but it’s a workhorse. At a ver low cost it’s a steal, especially when you consider it comes with two bottle brushes.
While it would be nice if it had a special compartment for smaller items, it’s not a necessity. And the tongs, like its electric sibling, are simply a waste of time. They’re too small and stiff to grip anything. I’m wondering why Munchkin bothers with them.
We considered and tested many alternatives for electric and microwave sterilizers. In picking our top choice, we acknowledge that others have fine qualities that can be helpful to some parents:
- Philips AVENT 3-in-1 Electric Steam Sterilizer —We really wanted to like this product because AVENT has been a leader in so many baby products. But this sterilizer has too many pieces and parts to put together, making the assembly confusing and increasing the chance of breaking or losing a piece. It does have a nice accessory basket that can go from the dishwasher to the sterilizer with ease, but if you’re already putting your baby bottles in the dishwasher, why do you want to sterilize? It seems a bit counterintuitive. It has a slim design but the many parts make it easily tippable, increasing the chance for injury.
- Dr. Brown’s Deluxe Electric Bottle Steam Sterilizer System—It takes some measure of skill to get all of the bottles and accessories to fit with ease into this sterilizer. While the Dr. Brown’s products may fit comfortably, any other brand will be a tight squeeze. With a nearly 12 minute cycle, and the necessary 10 minute cooling period, this electric sterilizer has the longest cycle of any tested. Far too long for any anxious parent. While it does feel more sturdy than other brands, it’s also big at 34-inches in circumference.
- Cuisinart CS-6 Baby Bottle Sterilizer—While the Cuisinart is taller than some of its competitors, it doesn’t offer features like the other brands such as an indicator when the cycle is completed. Some parents have complained that it doesn’t fit some bottles, like Dr. Brown’s, but we didn’t have that problem. It didn’t have an included accessory basket or tongs. The outside of the unit also got very hot to the touch after the cycle, unlike other brands.
- Playtex Smart Steam —This sterilizer also falls into the want-to-love category. When you take it out of the box, it seems so perfect. It’s sturdy, roomy and has a nice accessory basket. But that’s where the love ends. The water compartment is impossible to fill because the fill line is nearly invisible. The side snaps are too difficult to open and close and the overall size is not conducive to fitting all sized bottles. Probably the most problematic of the issues with the Smart Steam was the bottle placement. Instead of inserting bottles upside down so excess liquid would run off, its recommended that bottles be placed upright. That means all the condensation collects inside the bottles.
- Dr. Brown’s Microwave Steam Sterilizer—It seems ridiculous that Dr. Brown’s would make a bottle sterilizer that barely fits its own bottles. Sure, Dr. Brown’s 8-ounce standard bottles fit when they’re propped on their side, but with just a few bottles in the sterilizer, that’s all that fits. And if you decide to try any other brand bottle in the Dr. Brown’s sterilizer, you might be out of luck. They may or may not fit.
- Phillips AVENT Microwave Steam Sterilizer—The AVENT microwave might be a good model if you plan to use AVENT bottles exclusively and never switch to any other brand. AVENT makes it perfectly clear in the instruction booklet that it didn’t plan for any other bottle brands to be used in its steamer. Even if that wasn’t a factor, the AVENT microwave seems flimsy and easily overturned. It doesn’t have any latching feature like other comparable models
- Medela Quick Clean Micro-Steam Bags – While microwave steam bags are great for certain occasions, like work, they don’t offer the same capacity and flexibility like other microwave sterilizers. Still, parents rave about the Quick Clean’s impressive seal that doesn’t randomly pop open during heating like other brands. They love the small price (each bag can be used nearly two dozen times) and ease of use (all it takes is two ounces of water and a microwave).
Care, Use, Maintenance, and Repair
The biggest complaint about the Munchkin Steam Guard electric model is the sediment build up on the bottom. In fact, if you look at other electric sterilizer brands and models, its the biggest complaint overall. What most people fail to realize, either because of laziness or just being too tired (a new parent thing), is that all electric sterilizers must undergo periodic maintenance.
First and foremost, the items you put in the sterilizer, be it bottles, nipples, breast-pump parts or toys, must be cleaned before they go in. A stunning number of parents have complained that their bottles didn’t come out clean after a sterilization cycle. This isn’t a bottle cleaner and isn’t supposed to take the place of a good hand wash with hot water and soap.
Secondly, all sterilizers, both electric and microwave, must be emptied and dried after each use. Not only can leaving the water sit create a health hazard but it can also easily rust metal parts. And finally, most manufacturers recommend that sterilizers be cleaned after every few cycles because of the inevitable gunk that will develop. This descaling and decalcification cycle is easy enough with just vinegar and water. (The same as you’d do with a coffee carafe or humidifier.)
It’s also important to read the instructions. Yes, yes, it seems pointless at times read instruction about something as easy as sterilizer. But each sterilizer has very specific directions about the amount of water to put in. Too much water and the bottles won’t get sterilized properly. Too little water and your run the risk of ruining your machine (and creating a fire hazard complete with melted plastic).
what to look forward to
In the coming years, it’s easy to see that parents are going to be on the lookout for products that do more with less. There is likely to be more of a call for bottle sterilizers that use ultraviolet light instead of water, reducing the inherent problems with steam (potential for injuries, wet bottles, possible increase in germs). While there are some UV-sterilizers market, none seem to be made for sterilizing a large amount of bottles at the same time.
If parents are to stay with steam sterilizers, they’re likely going to demand machines with drying features. The residual drippy wet mess that comes as a result of steam sterilization is the fatal flaw in the process. Most parents don’t know what to make of it: should they dry the bottles by hand after the cycle and risk infecting them with germs again? Or should they wait the several hours it takes for them to dry?
- Should You Sterilize Your Baby’s Bottles?, WebMD.com
- Stevens, Emily, A History of Infant Feeding, Spring 2009
- Barakat, Zena, Ask Well: How to Clean Baby Bottles., December 18, 2013
- Basics on Processing & Sterilizing, University of Rochester Medical Center.
- BPA: Reducing Your Exposure, U.S. Food and Drug Administration
- Tavernise, Sabrina, F.D.A. Makes It Official: BPA Can’t Be Used in Baby Bottles and Cups, July 17, 2012
- Towle, Dana, et al, Baby bottle steam sterilizers disinfect home nebulizers inoculated with bacterial respiratory pathogen, Dec. 26, 2012
- Injuries and Deaths Associated with Nursery Products Among Children Younger than Age Five, Consumer Product Safety Commission
- timlewisnm, lined up bottles 04.05.09, Flickr, April 5th, 2009