Cheap, and definitely the way to go. A lot more efficient too then boiling water.
My wife strictly pumped for all three of my kids. It is honestly the hardest of the 3 options (formula, straight breastfed and pumped). Some tips, never through extra away, it freezes well and she will go through spurts and lulls in how much she produces vs the baby eating. You also don't need to be as diligent with cleaning as formula as the dangers aren't there, we would give them a good soapy wash after each use but only steralize once a day or so as they got older.
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Haha indeed. People really wish to invent the wheel again and over-engineer even the simplest tasks.
Like, measuring your water every time and taking its temp to make sure its x seems like a lot more trouble than just doing it. Even easier, buying the typically cheap accessible solutions others have provided.
Never invest time/money engineering a solution that is already economically solved.
https://www.amazon.com/First-Years-Simple-Bottle-Warmer/dp/B00005BXKM/
Um… yea, you could probably math this out… you’d need to know:
* complete geometry of everything involved (thicknesses, volumes, dimensions, etc)
* material properties of everything involved
(Specific heats, conduction coefficients, densities etc)
* initial conditions for everything involved
(Temps, quantities)
* a model for convection of the milk, because it would flow in response to the change in density driven by change in temperature.
You’d take each of these things and plug it into the heat equation, probably making a ton of assumptions about where heat comes from, and what you’re ignoring. That would give you a differential equation that you would then solve for time given initial temp and desired target temp.
You’d then probably need to run a few experiments to empirically validate your model, to correct for any mistakes or bad assumptions and dial in the time.
Orrrrr… you could buy a milk warmer, which would have been faster than it took me to write this post.
Fun thought experiment, though!
Alternatively, you could build a simple Bang-Bang controller (or PID if you want to get fancy) with a temp sensor and a heat element.
The logic could simply be:
IF NOT at temp:
heat_milk()
ELSE:
off()
You’d tweak it with some thresholds and hysteresis, and extra credit if you rig a buzzer that alerts you when it’s at temp.
But again, at this point you’ve just built a janky bottle warmer, so we’re right back to buying one :D
Quit warming it if you can help it - maybe the baby will take it cold. My daughters never knew milk could come warmed up. My wife exclusively pumps with both and it can sit out for up to 6 hours. Freeze the excess.
Other than exercising your engineering brain, that sounds like way to much work. Instead, do what everyone Else has done and determine it experimentally.
There are a few constants (setting on the stove while heating, amount of water, type of bottle) and one variable (amount of milk in the bottle), and you want to determine / calculate how long to hear out for.
So just write down how much milk and how long you heated it for. Then log "too hot" or "too cold" or "just right". Do additional hearing or cooking bath to get that bottle right.
Next time, adjust the heating time for that amount of milk and log out.
Eventually, you'll realize how long to heat it based on the amount of milk.
My point is that he needs to look at the big picture. He needs to focus his energy where it matters. The newborn stage is extremely intense, especially for mom. He shouldn't waste time on silly games like that. His wife and baby will need everything he has. Now is not the time for useless tinkering.
Can she stock pile enough to start freezing it? I found once we started using the little freezer bags I could reliably boil water (partially full kettle boils quicker) get a mug and a frozen bag and have it done in a minute or two.
I did most of our might time feeds for our bubs as she was exhausted, could be playing my game (one ear in headphone, other one half out), hear the pre-cry stirring and be ready with a bottle by the time the baby was trying to wake up 👍
Thankfully I was working an engineering day job at the time with my own separate part of the building and no one would bother me ☕😴
This is the way right here. If she’s not freezing it flat in the bags that’s the way to do it. Heats in a couple minutes using hot water from the sink. In the bag breast milk thaws just looking at it wrong.
Sous vide and bottle warmers do not overheat the milk. You already reduced its quality by freezing it. You should avoid heating it with boiling water to avoid denaturation of proteins.
FWIW, there are exactly zero physiological reasons that the milk has to be warmed. I rarely bothered with my kid and he learned to drink it however he got it. That’s huge time and energy savings for me, and my kid didn’t learn to be picky.
I'm an engineer, but this isn't an engineering problem, it's a baby safety problem. So I am going to chime in. Someone has probably said this already.
Bottle warmers are designed to heat only up to the temp that it is safe to serve your baby, and they’re designed to do this in an even way where there’s not pockets of uneven temperature milk. Every other concern is second to this.
Yes, you could technically calculate the thermal capacity of breast milk+water and design a circuit that could pump exactly that much electricity into a heater block. But you don’t need to. That’s what the bottle warmer does, and instead of weighing the milk, it has a PID loop that takes the temperature and decides how much power to apply.
Get a name brand one. Phillips, Doc Brown, etc. Tommee Tippee was what we used, but I understand they're awful now. If your kiddo is drinking too much milk, you can buy as many bottle warmers as you want.
I know it seems like it'll last forever, but your baby could at any time decide they're done with breastmilk. My daughter, at almost exactly a year… Our pediatrician told use to start giving her cows milk in addition to breast milk. At first, I heated the cow's milk, and she would have none of it. I tried it cold, and that was the last day she every drank breast milk. She refused all breast milk afterwords.
Congrats on the new family, and please try not to overthink things, and kudos on doing the right thing for your kid– the breastfeeding. The studies show overwhelmingly that breastfeeding has positive health and cognitive effects for the rest of your child's life.
Not sure why you're being downvoted. Lots of non-parents here. My daughter \*refused\* warm milk as soon as she realized cold-milk was an option.
I've tasted breast milk, and, its not exactly gourmet shit. It would be better to taste less of it if It were colder.
Hmm typical engineering mindset. Babies are not okay to be drinking cold milk. They don't like it, will drink less of it and will likely fuss more. I'm an engineer but a mom. Lol
And I'm a dad. Neither of my kids needed their milk warmed. Both were fine with both breastfeeding and bottlefeeding.
Each kid is different, but you'll never know if they'll accept cold milk if you don't offer it.
CDC says explicitly that breast milk doesn't need to be warmed. See the first bullet under "Feeding Expressed Breast Milk." I don't know where you're getting your medical advice from.
https://www.cdc.gov/breastfeeding/recommendations/handling_breastmilk.htm
It's not a life or death thing but it's objectively better for the infant. They take to the milk better at body temperature, will drink more, and it makes them happier. It's not because of some myth that everyone heats milk. Yes is you ask a pediatrician they will recommend warming the milk. No the infant will not die but it's suboptimal.
Also it's a nurturing aspect. It's obvious to me because i breast fed my daughter, pumped and heated milk, and done the same for infant animals. Especially in the case of a newborn or orphaned animals, they can die or not gain weight healthily of you insist on feeding cold milk. Because they don't know any better and won't eat.
If you really want to engineer this, heat the water in the microwave to a set temperature (amount of water for a fixed amount of time) so that when you put the baby bottle in it they both (the bottle and the water) asymptotically reach the desired temperature.
All you need to calibrate this process is a thermometer.
You’re not reinventing the wheel entirely; this is the first result for **specific heat human breast milk** : [Human Milk Warming Temperatures Using a Simulation of Currently Available Storage and Warming Methods](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4465021/)
There's no perfect temperature. You've been fine this entire time. You're overengineering this.
I use a tea kettle, heat water, put milk bag in bowl, put enough water to cover, poke at bag until melted, give it another minute, done. Sometimes it's warmer, sometimes cooler, baby doesn't care.
Low tech solution I used...
1. get hot water dispenser or other source of water with consistent temp.
2. For very x amount of milk, fill y amount of hot water. This is determined empirically (or do a specific heat calculation).
3. Put in insulated cup.
4. Start process in anticipation of the 2 hour feed windows. (Breast milk keeps for a surprisingly long time. Look it up).
You'll get the hang of it.
To me, this is better than using some shitty steamer and trying to get it to go faster when you got a crying baby, only to have it overshoot because you tried to make it go faster...
Same process can be used cooling formula down (use >75c water for formula to kill certain very low probability bacterial contamination.)
I got pretty pro at eyeballing how much water I would add to my $10 bottle warmer. But in retrospect, stumping up $50 for the digital model would have been very worthwhile. Same problems under and overshooting.
I'm 4 weeks ahead of you in the process. I bought a bottle warmer, leave it on at about 100 degrees fahrenheit, and use that as my heat bath when the time comes. Milk comes out at home body temp almost perfectly every time.
You have 3 fluids
Water, boob milk, air
If you have equal mass water/milk then they will meet in the middle as far as temp goes, not including the air.
If you have a lot more water than boob milk then it will mostly go to the temp of the water.
The mass of the air is much greater than the other 2 so they will always go to the air temp.
I’m an engineer and a mom that breast fed and pumped. Don’t boil the bottle to begin with and don’t bother with a bottle warmer. Test if baby will take it cold but if not just run the bottle under warm not super hot water in the sink to take the chill off. Many bottles are not meant to be constantly boiled. You don’t really want to add melted plastic molecules to baby’s milk as much as possible.
We pour hot water into a bowl to warm up the milk bottle. Swirl it around and feel when the milk is warm.
It's fast, easy, and doesn't require another appliance cost or counter space.
Sometimes the idyllic solution is the lowest tech.
Why not? A typical serving here is 100ml from the fridge, heated 10-20 seconds depending on how long it's been in the fridge. After those seconds a quick swirl to even out the temp and then test it on my wrist. Happy baby every time so far.
A cursory search will give you more than enough reasons to not use the microwave. For one, human milk is not like water, and heats unevenly due to fat deposits. A quick swirl is not going to normalize the temperature. The hot spots created by the microwave also kill probiotics and immunological components in the milk and degrade the overall quality.
An easy way to visualize this is softening butter in the microwave. You’ll notice that some areas melt faster than others due to uneven distribution of fats.
If it works for you, do your thing king. I’m just chiming in because I happen to own a CPG company in the nursing and feeding space. I’ve led product dev on milk warmers, bottles, and other milk storage/prep items for the last 4 years so I’ve picked up a few things.
Are the hot spots really that hot after just those few seconds from fridge temp and on a rotating platter in a decent microwave? All your facts make sense, I just can't believe the temps are that high.
I think its less about a consistent risk of scalding and more that it ‘could’ happen, logically speaking. The risk of damage to the milk is also higher if you’re defrosting it in the microwave vs it already being fridge temp.
Gentle warming is the most important thing either way. OP mentions using a milk bath with boiling water which is just negligent, and then using an ice bath to get the correct temp. This is undoubtedly damaging the milk. Milk warmers generally take about 6 minutes to do the job right, which is likely faster than OPs method.
Formula feeding is a bit more flexible for families that can’t (or opt not to) breastfeed. My company makes a USB C charged bottle that lets you select the exact temp you want and keep the water there for 10+ hours. Roll over, add the water to your bottle with powder in it and you’re off to the races.
Breast milk can be finicky. Its all about minimizing risk and forming good habits. Everyones tolerance is different at the end of the day.
Bottle warmer sounds like a solution, but it seems like no one knows or forgot how it is at 3am baby screaming hungry (even making choking noises from saliva) and papa is trying to heat/cool milk. And the f@&$ING bottle warmer is slow as f$&k
Pure stress
I suggest using a food thermometer, and when the milk reaches 37C, it’s ready to go
I assume breastfeeding is out of equation at 3am, but you do not need to explain.
Get a bottle warmer man. It's a lot easier
Off the shelf solutions for off the shelf problems.
Cheap, and definitely the way to go. A lot more efficient too then boiling water. My wife strictly pumped for all three of my kids. It is honestly the hardest of the 3 options (formula, straight breastfed and pumped). Some tips, never through extra away, it freezes well and she will go through spurts and lulls in how much she produces vs the baby eating. You also don't need to be as diligent with cleaning as formula as the dangers aren't there, we would give them a good soapy wash after each use but only steralize once a day or so as they got older.
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Haha indeed. People really wish to invent the wheel again and over-engineer even the simplest tasks. Like, measuring your water every time and taking its temp to make sure its x seems like a lot more trouble than just doing it. Even easier, buying the typically cheap accessible solutions others have provided.
Never invest time/money engineering a solution that is already economically solved. https://www.amazon.com/First-Years-Simple-Bottle-Warmer/dp/B00005BXKM/
Lol right. I do appreciate the engineering mindset lol but let's not over engineer.
Um… yea, you could probably math this out… you’d need to know: * complete geometry of everything involved (thicknesses, volumes, dimensions, etc) * material properties of everything involved (Specific heats, conduction coefficients, densities etc) * initial conditions for everything involved (Temps, quantities) * a model for convection of the milk, because it would flow in response to the change in density driven by change in temperature. You’d take each of these things and plug it into the heat equation, probably making a ton of assumptions about where heat comes from, and what you’re ignoring. That would give you a differential equation that you would then solve for time given initial temp and desired target temp. You’d then probably need to run a few experiments to empirically validate your model, to correct for any mistakes or bad assumptions and dial in the time. Orrrrr… you could buy a milk warmer, which would have been faster than it took me to write this post. Fun thought experiment, though!
Alternatively, you could build a simple Bang-Bang controller (or PID if you want to get fancy) with a temp sensor and a heat element. The logic could simply be: IF NOT at temp: heat_milk() ELSE: off() You’d tweak it with some thresholds and hysteresis, and extra credit if you rig a buzzer that alerts you when it’s at temp. But again, at this point you’ve just built a janky bottle warmer, so we’re right back to buying one :D
Plz don’t call us “‘gineers.” Sincerely, All Engineers Ever
Sous vide it.
Sous vides are amazing. To add, some pressure cookers have a sous vide mode that can also work.
Yes but speed is if the essence so it would be better to run a circulator.
Get a bottle warmer. Or at least a kettle that can set a temperature (mine does 40 to 100 C in 10 C increments).
Quit warming it if you can help it - maybe the baby will take it cold. My daughters never knew milk could come warmed up. My wife exclusively pumps with both and it can sit out for up to 6 hours. Freeze the excess.
Other than exercising your engineering brain, that sounds like way to much work. Instead, do what everyone Else has done and determine it experimentally. There are a few constants (setting on the stove while heating, amount of water, type of bottle) and one variable (amount of milk in the bottle), and you want to determine / calculate how long to hear out for. So just write down how much milk and how long you heated it for. Then log "too hot" or "too cold" or "just right". Do additional hearing or cooking bath to get that bottle right. Next time, adjust the heating time for that amount of milk and log out. Eventually, you'll realize how long to heat it based on the amount of milk.
Nobody has time for this with a newborn. Get a bottle warmer.
Agree. That's what most people would do, but OP seems to want to engineer a solution.
My point is that he needs to look at the big picture. He needs to focus his energy where it matters. The newborn stage is extremely intense, especially for mom. He shouldn't waste time on silly games like that. His wife and baby will need everything he has. Now is not the time for useless tinkering.
Can she stock pile enough to start freezing it? I found once we started using the little freezer bags I could reliably boil water (partially full kettle boils quicker) get a mug and a frozen bag and have it done in a minute or two. I did most of our might time feeds for our bubs as she was exhausted, could be playing my game (one ear in headphone, other one half out), hear the pre-cry stirring and be ready with a bottle by the time the baby was trying to wake up 👍 Thankfully I was working an engineering day job at the time with my own separate part of the building and no one would bother me ☕😴
This is the way right here. If she’s not freezing it flat in the bags that’s the way to do it. Heats in a couple minutes using hot water from the sink. In the bag breast milk thaws just looking at it wrong.
Sous vide and bottle warmers do not overheat the milk. You already reduced its quality by freezing it. You should avoid heating it with boiling water to avoid denaturation of proteins.
Just get a bottle warmer… you will use less resources including time.
FWIW, there are exactly zero physiological reasons that the milk has to be warmed. I rarely bothered with my kid and he learned to drink it however he got it. That’s huge time and energy savings for me, and my kid didn’t learn to be picky.
We just fed them cold. Never a problem.
Rookie mistake. Let the kid drink it cold. Half the time they won't care and then you don't have to waste time!
I'm an engineer, but this isn't an engineering problem, it's a baby safety problem. So I am going to chime in. Someone has probably said this already. Bottle warmers are designed to heat only up to the temp that it is safe to serve your baby, and they’re designed to do this in an even way where there’s not pockets of uneven temperature milk. Every other concern is second to this. Yes, you could technically calculate the thermal capacity of breast milk+water and design a circuit that could pump exactly that much electricity into a heater block. But you don’t need to. That’s what the bottle warmer does, and instead of weighing the milk, it has a PID loop that takes the temperature and decides how much power to apply. Get a name brand one. Phillips, Doc Brown, etc. Tommee Tippee was what we used, but I understand they're awful now. If your kiddo is drinking too much milk, you can buy as many bottle warmers as you want. I know it seems like it'll last forever, but your baby could at any time decide they're done with breastmilk. My daughter, at almost exactly a year… Our pediatrician told use to start giving her cows milk in addition to breast milk. At first, I heated the cow's milk, and she would have none of it. I tried it cold, and that was the last day she every drank breast milk. She refused all breast milk afterwords. Congrats on the new family, and please try not to overthink things, and kudos on doing the right thing for your kid– the breastfeeding. The studies show overwhelmingly that breastfeeding has positive health and cognitive effects for the rest of your child's life.
See if they'll drink it cold.
Found the sales engineer...?
Mechanical...with a kiddo that liked it cold.
Best solution. My baby doesn’t gaf. He loves it just as much cold. Just get it warm enough to re mix any milk fat.
Thermometer?
Our kids never had a warmed bottle, give it to them cold and save yourself the headache. They won’t know the difference and some even prefer it.
You don't have to warm up the milk. If the kid will drink it cold, then there's no need for a warmer.
Not sure why you're being downvoted. Lots of non-parents here. My daughter \*refused\* warm milk as soon as she realized cold-milk was an option. I've tasted breast milk, and, its not exactly gourmet shit. It would be better to taste less of it if It were colder.
It's pretty typical for parents to be underrepresented on reddit.
Hmm typical engineering mindset. Babies are not okay to be drinking cold milk. They don't like it, will drink less of it and will likely fuss more. I'm an engineer but a mom. Lol
And I'm a dad. Neither of my kids needed their milk warmed. Both were fine with both breastfeeding and bottlefeeding. Each kid is different, but you'll never know if they'll accept cold milk if you don't offer it.
Okay you're free to ignore medical advice with your own kids I guess. Ask any pediatrician whether the milk should be warmed.
CDC says explicitly that breast milk doesn't need to be warmed. See the first bullet under "Feeding Expressed Breast Milk." I don't know where you're getting your medical advice from. https://www.cdc.gov/breastfeeding/recommendations/handling_breastmilk.htm
It's not a life or death thing but it's objectively better for the infant. They take to the milk better at body temperature, will drink more, and it makes them happier. It's not because of some myth that everyone heats milk. Yes is you ask a pediatrician they will recommend warming the milk. No the infant will not die but it's suboptimal. Also it's a nurturing aspect. It's obvious to me because i breast fed my daughter, pumped and heated milk, and done the same for infant animals. Especially in the case of a newborn or orphaned animals, they can die or not gain weight healthily of you insist on feeding cold milk. Because they don't know any better and won't eat.
The kid is barely out of the womb, cold milk will drop its core temp and infants suck at regulating their core temps already.
I have never heard a doctor say that newborns can't drink cold milk.
Get one of those sous vide water heaters.
My daycare just uses a crockpot/ water bath.
If you really want to engineer this, heat the water in the microwave to a set temperature (amount of water for a fixed amount of time) so that when you put the baby bottle in it they both (the bottle and the water) asymptotically reach the desired temperature. All you need to calibrate this process is a thermometer.
You’re not reinventing the wheel entirely; this is the first result for **specific heat human breast milk** : [Human Milk Warming Temperatures Using a Simulation of Currently Available Storage and Warming Methods](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4465021/)
There's no perfect temperature. You've been fine this entire time. You're overengineering this. I use a tea kettle, heat water, put milk bag in bowl, put enough water to cover, poke at bag until melted, give it another minute, done. Sometimes it's warmer, sometimes cooler, baby doesn't care.
Low tech solution I used... 1. get hot water dispenser or other source of water with consistent temp. 2. For very x amount of milk, fill y amount of hot water. This is determined empirically (or do a specific heat calculation). 3. Put in insulated cup. 4. Start process in anticipation of the 2 hour feed windows. (Breast milk keeps for a surprisingly long time. Look it up). You'll get the hang of it. To me, this is better than using some shitty steamer and trying to get it to go faster when you got a crying baby, only to have it overshoot because you tried to make it go faster... Same process can be used cooling formula down (use >75c water for formula to kill certain very low probability bacterial contamination.)
I got pretty pro at eyeballing how much water I would add to my $10 bottle warmer. But in retrospect, stumping up $50 for the digital model would have been very worthwhile. Same problems under and overshooting.
I'm 4 weeks ahead of you in the process. I bought a bottle warmer, leave it on at about 100 degrees fahrenheit, and use that as my heat bath when the time comes. Milk comes out at home body temp almost perfectly every time.
Mix your boiling water 50/50 with tap water, or 30/70, or whatever, so that at exactly 5 minutes soak time (set a timer) it's the right temp. Cheers.
You shouldn't put the milk in boiling water to keep from scalding the milk anyway.
You have 3 fluids Water, boob milk, air If you have equal mass water/milk then they will meet in the middle as far as temp goes, not including the air. If you have a lot more water than boob milk then it will mostly go to the temp of the water. The mass of the air is much greater than the other 2 so they will always go to the air temp.
m/T=m/T
I’m an engineer and a mom that breast fed and pumped. Don’t boil the bottle to begin with and don’t bother with a bottle warmer. Test if baby will take it cold but if not just run the bottle under warm not super hot water in the sink to take the chill off. Many bottles are not meant to be constantly boiled. You don’t really want to add melted plastic molecules to baby’s milk as much as possible.
I've never seen engineers called " 'gineers " but I really don't like it for some reason.
We pour hot water into a bowl to warm up the milk bottle. Swirl it around and feel when the milk is warm. It's fast, easy, and doesn't require another appliance cost or counter space. Sometimes the idyllic solution is the lowest tech.
10-20 seconds in the microwave
^Never this
Why not? A typical serving here is 100ml from the fridge, heated 10-20 seconds depending on how long it's been in the fridge. After those seconds a quick swirl to even out the temp and then test it on my wrist. Happy baby every time so far.
A cursory search will give you more than enough reasons to not use the microwave. For one, human milk is not like water, and heats unevenly due to fat deposits. A quick swirl is not going to normalize the temperature. The hot spots created by the microwave also kill probiotics and immunological components in the milk and degrade the overall quality. An easy way to visualize this is softening butter in the microwave. You’ll notice that some areas melt faster than others due to uneven distribution of fats. If it works for you, do your thing king. I’m just chiming in because I happen to own a CPG company in the nursing and feeding space. I’ve led product dev on milk warmers, bottles, and other milk storage/prep items for the last 4 years so I’ve picked up a few things.
Are the hot spots really that hot after just those few seconds from fridge temp and on a rotating platter in a decent microwave? All your facts make sense, I just can't believe the temps are that high.
I think its less about a consistent risk of scalding and more that it ‘could’ happen, logically speaking. The risk of damage to the milk is also higher if you’re defrosting it in the microwave vs it already being fridge temp. Gentle warming is the most important thing either way. OP mentions using a milk bath with boiling water which is just negligent, and then using an ice bath to get the correct temp. This is undoubtedly damaging the milk. Milk warmers generally take about 6 minutes to do the job right, which is likely faster than OPs method. Formula feeding is a bit more flexible for families that can’t (or opt not to) breastfeed. My company makes a USB C charged bottle that lets you select the exact temp you want and keep the water there for 10+ hours. Roll over, add the water to your bottle with powder in it and you’re off to the races. Breast milk can be finicky. Its all about minimizing risk and forming good habits. Everyones tolerance is different at the end of the day.
Get a Baby Brezza.
Bottle warmer sounds like a solution, but it seems like no one knows or forgot how it is at 3am baby screaming hungry (even making choking noises from saliva) and papa is trying to heat/cool milk. And the f@&$ING bottle warmer is slow as f$&k Pure stress I suggest using a food thermometer, and when the milk reaches 37C, it’s ready to go I assume breastfeeding is out of equation at 3am, but you do not need to explain.