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Ep. 77- Milk Storage Guidelines: A closer look

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This is Maureen Farrell and Heather O’Neal and this is The Milk Minute. We’re midwives and lactation professionals bringing you the most up-to-date evidence for all things lactation. So you can feel more confident about feeding your baby, body positivity, relationships, and mental health. Plus, we laugh a little or a lot along the way. So join us for another episode.

Okay. You want to start with a joke? I do want to start with a joke. I mean, why shouldn’t we start every episode with a joke? All right, tell me your joke. So this is a shout out to Martha at work, who was one of the funniest people I’ve ever met and also is my friend that does not know how to whisper.

So when she’s talking shit on residents on the unit it’s very funny because I’m like, Martha, you’re not quiet. Definitely heard you. So anyway, the other day she says, Hey, I got a joke for you. I know you’re going to love this one. And I said, great.

And she goes, so there’s a little boy. And he goes up to his grandpa and he says, grandpa, what’s that called when one person is sleeping on top of the other person? You know. And his grandpa goes well, all right. I’m just not going to beat around the bush. I think he’s old enough to know. And he goes, it’s called sex. And he goes, oh, okay. The next day a little boy comes up to his grandpa and he says, Hey, grandpa remember yesterday, when I asked you what it was called when one person sleeps on top of the other person? And grandpa says yes. And he goes, well, it’s called bunk beds. And mommy wants to talk to you.

Sounds like every conversation I have with my son, right. Oh, okay. Let’s talk about racism then, or let’s talk about sex or what, and he’s just like, mom, it was just a simple question. It’s not what I was asking. Yeah. Let’s not get too deep, mom. Don’t worry. I’m not quite damaged yet. Speaking of which, oh my gosh.

Yesterday, so my son just turned six and we were like hanging out in bed and watching a movie with the baby and I called him baby, which like I do all the time and he just dead pan looks at me, mom. I am not a baby. Oh, well, I guess we’ll just mark it down in the baby book.

Well, when Heidi was potty training, which is still happening, yes. When we were tackling step one of potty training, which was peeing in the potty, we read that, something about crap. Oh, crap. Everybody poops? Now it’s called Oh, crap! Potty training. Yeah, whatever. It told us not to call Heidi a baby anymore. And that we’re supposed to help her move towards her identity of being a big girl and big girls pee in the potty.

Whatever. So we stopped calling her baby, but then she heard my dad call me baby. And she said, you’re not pop pop’s, baby. And my dad goes, Heather will always be pop pop’s baby. And now Heidi called me pop pop’s baby for like a week.

You pop pop’s baby? I said, yeah. And her new thing this week is she goes, are you Heather or mommy? And I said, I’m both. And she goes, you Heather AND mommy? And I said, yes. And she, her little brain was just like calculating, calculating, trying to figure that one out. Yeah. One of my friend’s kids called my other friend, mom for like two years cause he didn’t get her name was not mom. But her son called her mom, so he was like, oh, you’re mom like your name is mom, like, like mine. Mom, every mom, someone shouts mom on the playground and all the moms go, what? It’s very confusing for children. We don’t have identities. We’re just one amorphous mom. Yeah.

Anyway, should we jump right into the content? Yeah. Do you guys want to know what we’re talking about today? Or you just want to hear us keep bullshitting? Well, I will let you know today we’re going to talk about milk storage guidelines, which feels real controversial, sometimes. Constroversial, controversial.

It’s like being constipated with medical information that’s also controversial. So before Heather starts criticizing the way I’m speaking, let’s pull a listener question. This listener question is from one of our patrons. Hurray. Yeah. This is from Lisa and Lisa’s great. And she’s asking why is my six-month-old growling and grunting?

He does it while nursing and wiggling all around. And sometimes when he’s not nursing, am I really raising a bear cub? Lisa, we hate to tell you this, but yes, you are raising a bear cub. Yes. Yes. So, but at that age more than anything, especially if you’re like he’s growling and grunting not just while nursing or not just while in this position.

It’s, it’s literally probably vocal experimentation. Oh yeah. Their voices are changing and they’re getting used to hearing their own voice. And that’s one of the biggest beginning phases of language development is like, oh, this is my voice. And I have control of it and then comes to the constant screaming for fun.

Yeah. They’re like, I can make a noise on purpose. Even my five-month-old. Now she’ll be nursing and she’s *squealing noises*.

And like boob in mouth let’s just see which octaves we can use. With a younger baby, if we’re grunting, while nursing, we’re probably having some gas pain. Yep. They do that. Maybe also with a six-month-old, but more likely they’re just like, wait. I can talk. Yeah. Yeah. The grunting and growling is specific for each different baby.

Both my kids made different kinds of noises. You know, my daughter was more of like a, like a screamer. Yeah. Lyra’s doing this squealy thing, but like, I don’t think Griffin has ever done in his life. Yeah. My son is more like business, you know, he was like, I’m going to eat this boob. And then I got to go, like I got baby stuff to do.

So he didn’t really like spend a lot of time singing or messing around. He just was kind of like I’m eating, I’m done. Yeah. Lyra hangs on. She’ll like, you know, do her whole, like gulpy thing that you guys all hear when my let down is a lot. And then she just hangs on doing nothing. And then just starts like, *creaking noises* then you’re like. Like a creaking door.

So we’re just singing. She becomes haunted after 20 minutes of nursing. Yeah. It’s I mean, it’s almost Halloween. Griffin is so excited that Lyra is going to be six months old before Halloween because she can have candy, right? Oh, God. He’s like, I’ll share my Halloween candy with my sister. That’s so cute. And you’re like, no. Anyway, she can eat some pumpkin.

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Heather, we’re here to talk about human milk storage guidelines. I’m kind of delaying it because it’s just, it seems stressful and. Oh no, I’m excited. Okay. Yeah, let’s go. Okay. So I’m excited because I think I found a little bit of clarity. Oh, my God. Are you serious? Well you’ll see. Okay. So you guys probably already know if you have looked at milk storage guidelines in more than one place you’re like already confused.

And if you’ve talked to more than one medical professional about milk storage guidelines, they’ve probably given you different advice and perpetuated the confusion. And to add onto that, like every single pump manufacturer, just like throws some random shit out there on their website about how to take care of their specific pump and also here’s how you store your milk.

They have no authority there. Yeah. And it’s not even varying by minutes. It’s like hours, days. It’s a lot. It’s a lot. So I went through a couple of different like big healthcare organization guidelines to start with. And then I went to the Academy of Breastfeeding Medicine’s Protocol Number Eight, which is what we’re really gonna mostly focus on today. Because frankly, when you go to places like the AAP or the WHO, like you’ll see the guidelines, but that’s it. They don’t list their sources.

 They’re like, these are for parents, not for clinicians. So parents apparently don’t care what we’re doing and where we got it. Let’s just make it simple and easy to follow, which I understand. But also like totally is a disservice to all of you guys out there who are intelligent, like well reasoning people who can make complex decisions, you know?

How often are those updated and who’s in charge of updating them? And, you know, like if a new awesome scientific paper comes out, that would really change the storage guidelines, how many years is it going to be before those are updated? Right? And even this, this Protocol Number Eight was revised in 2017.

So it’s there are a couple things that were out of date, but for the most part, I mean, it’s pretty good. And what I like about this protocol is it’s not just like how long to store your milk. It’s kind of everything surrounding milk expression and what guidelines we should use for safety around that. And what makes sense, hopefully.

Right. And I mean, as far as I could tell it was evidence-based, you know, there are like 50 articles cited and I did go through and read a number of them when I was like, wait, what the heck is this one about? And this is ABM. Yes. Okay. Breastfeeding medicine and their protocols are written for clinicians.

Not for parents, which I appreciate and parents can access them too. Hooray! So to be clear, this is for storage information for home use for full term infants. Yeah. If you’re nursing a premature baby, you pretty much need to do what they told you to do in the NICU. That’s going to be your best bet. You know what the first rule is, Heather?

I hope it’s wash your hands. It is, it is literally like, I don’t know why this isn’t just at the top of every like little PDF or magnet you put on the fridge. Wash your damn hands. Don’t go poop and then pump and store your milk for four days. Because the ha like everything I was reading, every article I went through, the base bacteria account had a huge impact on the shelf life and safety of the food.

Duh. Yeah. You can only ask so much of your milk outside of your body, right? You can’t just be like, well, I just wiped my butt and now there’s fecal matter in this milk, but it’s good for 8 hours on the counter. And the reality is, yeah, it’s probably fine for a couple hours, but if you really want to get the most out of all of these guidelines, the cleaner you are at the onset of this whole process, the, the, like, you know, more lenient you can be with these guidelines.

Great. Okay. So wash your hands. Now real studies have shown that human milk containing less foreign bacteria at the time of expression shows less bacterial growth in storage, and actually has a higher protein content after storage. So cool. Bacteria is like not eating your milk but cleaning your breasts is not necessary.

Thanks Montgomery glands. Oh, yeah. Good Montgomery glands are the little bumps on your areola. When people try to pop them, don’t, pop them, please. First, I’m looking at you. If you’re a picker, you need to pick something else because those little bumps on your areola are glands that secrete wonderful, wonderful lubrication for your nipples. Keeps them moisturized.

And it also has properties that keep your nipple clean for you, right. And frankly, like you’re not just like rubbing your bare breasts on every surface you encounter throughout the day. But like you do that with your hands. Let’s just be real.

You’re not like, let me just rub a nipple on this handrail. My nipples are so hard I could poke the elevator button with them. But if you are pressing elevator buttons with your nipples, then maybe you should wash them and take a video and put it on Instagram. Okay. So second, wash your hands. Next, whether you hand express or pump turns out, doesn’t matter for overall bacterial growth in general.

Cool. Yeah. Cool to know. So it’s not like you have to use extra cleaning protocols. Cool thing about this one, we go into some storage container choices. Are you interested? I’m very interested because there’s been some changes in the market. And if you haven’t checked out our Ceres Chill episode, where we interview the founder of Ceres Chill, Lisa Myers.

She’s badass. We love her. And she has been really spearheading the discussion around milk storage guidelines and really pushing to get them updated for parents to have more options that are safe, which we love because progress is great. Yeah. So of course, for whatever reason, there was a ton of research into this and not in other areas that I frankly find more important.

But basically in all the possible containers tested, which among these studies, we had glass, polyethylene, polypropylene, polycarbonate, polyether sulfone and steel. So all those poly ones are plastic, by the way. I didn’t see silicone included just FYI, but among all of those, basically there was always a significant reduction in the percentage of fat and some of them showed increases in total protein or carbohydrate concentrations after storage, which we can conclude is from like enzyme stuff happening in milk.

Yeah. But no matter what, fat is going to stick to the sides. Okay. And there’s nothing we can really do about it. The swirling helps. Yeah, you can try, but you know, like get it off the best you can also it’s just going to be there.

Somebody posted in our Facebook group a tiny little spatula that they bought just for getting in their tiny little bottles. But isn’t it like going to be stuck to the spatula? And then you just like scrape it in. Is it one of those butt spatulas? No, it’s like one of those makeup spatulas like you can buy a set on Amazon (link in the show notes ?), where you can like scrape it off the sides and it’s super tiny. So it’ll like get in the nipple too.

I had to Google, butt spatula not too long ago, because it was like, my friend was asking for recommendations for her like registry and someone was like the butt spatula. And I was like, what is the butt spatula? It’s, it’s a little silicone spatula you put diaper cream on baby’s butt with, so you’re not like in there with your finger.

Oh my God. That would have been very helpful. Now that we’re all done having babies. I’ll get you a butt spatula for your birthday. But like, then you’d miss out on that opportunity to lick your finger two hours later, you got peanut butter on it.

And you’re like, oh, Desitin. Yeah. Even though you washed your hands, that stuff will not come off. But that’s the point of Desitin right? Is that it’s just like a whole new skin, right? Get a butt spatula. Cool. Anyway, or a milk spatula. So we’re talking about milk storage though. The, the interesting thing was at least one of the studies showed that using polyethylene plastic had a significant drop in some of the immunoglobulins and the bactericidal effects of milk when compared to glass.

Do you have an example of one of those? Is that like the Playtex bags? Yeah. I actually need to look up if like, which ones each brand is made of, but I didn’t really care too right now, but yeah, it’s like using the Medela bags or whatever, versus using a glass jar. And you know, some of the steel container showed a decrease in the cell count and viability as compared to the glass as well.

 But honestly, like not all of the results were super consistent. We don’t know if the methods in expression were all the same in those studies. So there’s a lot of like, how much does this matter? How much control do we have over this? The conclusion is like maybe glass is the preferable choice, but basically every container tested, showed a reduction in fat content and some cell viability.

And that’s important to know if you have a baby that’s really struggling with weight gain, you know, and you’re pumping exclusively, you know. That, so that’s not a deal breaker for pumping by any means, but it’s just something to note. And, you know, honestly, like there was some you know, I’ll mention this later, but there was some mention of caloric content actually reducing over time in storage, which may be one of the missing pieces that we, we kind of haven’t thought about much when people are like, wow, I can’t keep up with my baby’s intake when I’m pumping at work.

Like maybe that milk is actually just a little bit calorically less. Yeah. It it’s interesting that we’re really only just jumping into research on this. And frankly, a lot of the studies cited were already like 15 years old and there’s been no new study done. Guys if I had time to get my PhD, I would do it. Someday.

Yeah. But regardless of what container you choose no judgment. If it’s a reusable container, we’re going to treat it like our pumps as far as cleaning. So. This one, just get ready, sit back. You’re going to like this. Pumps and reusable storage containers should be washed and hot, soapy water or in a dishwasher. Air dried or dried with paper towels and they don’t need to be sterilized.

What? They don’t need to be sterilized for a healthy full-term infant. Why? Boom. I’ll get into that. Okay. So I read that and I was like, hold on, let me look at that little number and go to the footnote and the source because hello, rabbit hole. This was fun. So this led me to an article published in the Journal of Hospital Infections.

Didn’t know that existed. It’s probably fascinating and terrifying, but it’ll make everyone do a home birth anyway. So they have this working group analyze like all of the available literature from hospitals and then additionally created a survey in UK neonatal units. So they concluded basically that given proper instructions, it’s totally sufficient for parents to clean pumping and storage equipment, just with washing in hot soapy water rinsing and drying.

This applies only to single pumping units being used by a single lactating parent, not the shared hospital units. Those they said should be sterilized between uses, between peoples. Does it matter how long you plan to store the milk?

No, essentially excluding for special medical circumstances from, with the babies, the chance of infection in their neonate and the, the bacteria content of the milk and everything. It was all the same. Whether or not people fucking boil those pump parts or not. Oh, well, good. Yeah. So you just got 15 minutes of your day back.

And honestly, like I have been thinking about that. I never boil my pump parts guys. Like I did it once when I opened the packet and it’s been four months. She’s fine. I mean, I was just thinking like, literally what is going to change between me using this water that is so hot, hot it scalds my skin, because we have a very hot water heater and this like ridiculously, you know, I use like Dawn on my pump parts, maybe I shouldn’t, you know, and scrubbing the shit out of them. Like what’s going to change then if I boil it after that? Yeah. Interesting though, they then said if for some reason you can’t get to soap, like say we’re in an emergency situation, you can boil alternatively.

And they said don’t use chemical cleaners like chemical disinfectants that you just like dip and dry because it leaves a bunch of residue. Yeah, that makes sense. Yeah. So enjoy your freedom, everybody. Did we talk about this in our, How to Clean and Manage Pump Parts? And we said, we told people to boil it because that’s the guidelines like everywhere else.

Well, the pumping parts are probably different than the storage right? No, I mean, it’s all the same. How is it all the same? If they’re reusable storage containers that you’re using and pumping parts. They lump them all into one. If you’re just using the one-time bags, they’re already come sterile. The pumping parts themselves have so many little areas that. So that is why the guidelines tell you to also boil is because they assume you’re not going to sufficiently clean.

So this recommendation is saying like, if you give parents the right instruction. Oh, right. And so that is like the crux point of why these guidelines vary and why the CDC guidelines kind of suck so much is because they’re assuming the worst adherence to the guideline, which I understand. I understand.

Absolutely. But it doesn’t give you any information then to make a decision that actually works for you or is even the safest for you. And it also just contributes to that anxiety that you have as like a intelligent contributing member of society that doesn’t have problems following any other rules, but the ones that they give you in breastfeeding seem complicated.

Like when, when women that were in WIC programs were polled in the beginning, what affected their decision to breastfeed or formula feed? They reported that they chose to formula feed based on the WIC presentations of each type of method, because the breastfeeding one was presented in a way that sounded complicated.

Wow. So they were like, oh shit, we, we better change how we’re presenting this to people. It’s like, okay, if you’re formula feeding, here’s the rules and this much, and this amount at this time and mix it this way. Breastfeeding, it’s like, sit down, girl, we got to talk. It’s going to be a long road. There’s a lot of rules that are very arbitrary.

And you won’t know which ones apply to you until you listen to this podcast. An interesting side note, actually, one of the, like professional breastfeeding education and courses I took suggested that in order to like combat that, that when parents choose to formula feed, we show them like this video, I think the who made it, that was very much like here are the exact guidelines for how to make formula. Which by the way, like to make it quote, like totally safely, is fucking hard.

You know, like sterilize your little scoop and put it down and don’t touch it. It’s like canning food, you know. You’ve got like a sterile setup in front of you and all of your tools and you pick it up with the tong and it’s a lot. And I don’t necessarily agree with like causing unnecessary anxiety for formula feeding parents either.

But it was like definitely an interesting exercise to kind of turn that on its head. And be like, actually the guidelines suck for everybody. Feeding your kid is just hard. The easiest way to feed your kid, as it turns out is to not store your milk and to just feed them directly from the boob, but America and, you know, working and all that.

Okay. So now I’m actually going to get into the big question everyone has like Heather, if I left my milk out for 4.1 hours, is it still safe? The CDC says no. I say yes. Me too. And here’s why, because that is BS. Yeah. So we’re going to start, like, we’re going to move down temperature gradients, right?

Warmest first and also most variable is room temp. This protocol defines room temperature as between 50- and 85-degrees Fahrenheit, which is like really big or between 10 and 29 degrees Celsius, which we don’t use in the US. This is for our EU friends. Yeah. Anyway, I don’t know what that means. I assume, you know, no reference point for that, but I assume it’s the same gradient.

Anyway. So their guidelines say that like some limited studies suggest that, of course the shelf life of breast milk at this very large variation of temperature varies due to the actual temperature and due to the cleanliness while collecting milk. Right. So essentially if you are a little bit slapdash and maybe you didn’t wash your hands and maybe your pump parts aren’t super clean and it’s 85 degrees in your house, four hours is a reasonable limit to assume it’s safe.

But if you wash your hands and your pump parts are clean and maybe your house is like 65 degrees instead of 85, then study suggests we’re looking more like eight hours. Yeah, that makes sense to me. I mean, I love it when common sense wins. Yeah. And it’s logical and I kind of wish we would like; this is what we’re doing.

I’m giving you the tools to make this decision on your own. Yeah, because your, your house changes. Your situation changes day to day. If you’re pumping in a car and then you have to you know, and you’re at a soccer meet and you’ve got dirt everywhere, and you’re just doing the best you can, but you have to pump, and then you have nowhere to put it, but in your car for the next two hours, you know, that’s something to consider.

Maybe like use it sooner. Yeah. It doesn’t mean throw it out. It doesn’t mean, oh, I guess you’re going to just have to use it for a milk bath. Which is the answer now, apparently for all the milk. Have you seen that in the group? Should we just do an episode on mike baths? I’ve been thinking it, but then I’m like, what would we say? Milk baths are getting a serious PR push right now and I’m not sure why.

I mean, it sounds like sure. Yeah. Also like what? It cures everything, it’s kind of as if I were saying, like, why don’t you bathe in kitten milk? Uh, ew. That just did something to me. That’s disgusting. It just seems like such an extravagant thing. Like, like it’s so hard to milk a human, and now we’re going to take a bath in it. Well, I was going to throw it out, but why not bathe in it?

No, definitely give your kids milk baths. It’s not dangerous, guys. It just seems like hilarious to me. Just don’t throw away good milk to do it. That’s the big thing. Like, I, we have seen a lot of Facebook posts like, oh no, my milk is now 12 months and one day old. So I’m going to make a milk bath with a hundred ounces of milk.

Like what just happened? Did I intervene soon enough to stop? Oh no, there’s a picture. Oh shit. Ah, okay. Yeah. So anyway, essentially, like, you know, just, just think about it. Is this your cleanest milk expression? Is it a cooler room or did Heather turn off the air so that our recording was better and now I’ve left it out in an 85-degree room?

You’re welcome. It’s alright I’ve got it in the chiller. Okay. So speaking of the chiller, we’re talking about ice packs next. Also very variable. Yeah. Yes I, okay. I’m sorry. Go ahead. I will interject. Tell me. Here’s the other thing that’s been floating around our group. Your milk is good until the last ice crystal has melted for 24 hours.

And it’s like, what is up with this last ice crystal? I have, I do have a slight clarification on that, but like, not as clear as I, yeah. Okay. Like everyone is just hanging by the last ice crystal. Like I found my freezer open again because Griffin closed it with the Roomba cord for the charger in it, and I opened it and there was just little like snow everywhere, you know? And I was like, ah, but everything was still frozen. It was just like frosty. Yeah. Okay. Also if it wasn’t, I would’ve been like shit, shut that freezer. Cause, well, my system too, I keep the law. Like I have like 80 ounces in the deep freeze. That’s my, like, I’m going to be in a four-day birth stash.

Cause that happens. I hope you’re not at a four-day birth. No, same, but like, you know, it’s a, it’s a possibility. And then in the little freezer attached to my fridge, I keep like 12 ounces, you know? Yep. At most, because like, we’re not going to use more in a day of me being at work. Right. And that’s also the fridge that like somebody always leaves open anyway.

Smart. I don’t even date that milk. cause I’m like it’s going to get used this week. And if it doesn’t, I’ll throw on the date of Monday and put it in the freezer. There you go. Anyway, ice packs. What the heck? What temperature are ice packs at guys? What size is your cooler? How much ice is in it? This is really variable.

Like sometimes you open a cooler and you’re like, this is not even colder than this room. So this particular paper said that basically we’re looking at around 60 degrees Fahrenheit or 15 degrees Celsius. It’s not that cold. It’s like a cold room. So they’re giving you a lot of leeway. Like this is kind of worst-case scenario, your cooler’s keeping it like just a little colder than your room.

So are we talking about you’ve freshly pumped it and you’re putting it in a cooler because my understanding is the recommendation is it’s fine on ice packs in a cooler for 24 hours? Right. And that’s where this comes from is at that temperature at about 60 degrees Fahrenheit. Okay. So, but isn’t your refrigerator 40?

 So it’s warmer than your fridge. Okay. Yeah, I mean, and because they’re acknowledging that, like you put an ice pack in, maybe the cooler is 30 degrees and then 10 hours later, it’s 50 and then 10 hours later, it’s 60 you know, like ice packs melt. Is it a lunchbox cooler, right? Is it a Yeti? So this said a small cooler with ice packs.

Okay, because we basically don’t have a lot of study. I think there was like one study with small, like, like those little Medela coolers that come with the things like that. So, but if you have like a bad-ass Yeti cooler, you know, and it’s keeping it at a chill, like 35. You’ve got four days. Right.

And if someone’s not opening it and closing it repeatedly and letting air out, if you just pump, put it in there and zip it and fly with it somewhere and you don’t open it for 24 hours and it’s a really good cooler, it really might be still at 40 degrees. Yeah. And you know, like, this is where the question we get a lot, like I’m moving across the country and I have like 500 ounces of milk and we’re just like, whoa, don’t freak out.

Don’t throw your milk out, shove it in a cooler duct tape it shut. You’re going to be okay. Right. Yeah. So. It should be safe for about at least 24 hours at the temperature. If it’s lower, it’s going to be longer. So if you forgot your milk in a cooler with an ice pack and it’s like 40 degrees at night in your car, like, don’t worry about it.

Put it in your fridge. It’s okay. Should the title of this episode be Milk Storage Guidelines: Do What Makes Sense. It’s okay. I feel like I just need to, like, we need to take a collective deep breath.

Channel Lisa Myers here. Remember “breastmilk is not fragile”. Yes. It’s not fragile or fragile. Fragile. Flagellated add an extra syllable. No, but we do. We have to remember it’s not fragile. And remember a little bit of common sense, right? If you open your cooler and you’re like, that is a room temp, solid room, temperature, 72, you know assess how long it’s been in there, you know, think through like, Hmm.

Was it actually very cold when I put it in? Are we looking at kind of room temp? Yeah, you can always do a taste test. Smell it. It’s okay. And if you’re going to do a taste test, pour it into a spoon and then taste it. Don’t put your mouth bacteria in it and then try to store it. If you, if you taste it with your mouth and you’re like, yep, still good.

And then throw that in the fridge. Now it might not be anymore, you know? And also, I just want to say before you throw it out, just like take a breath. Because I’ve had a lot of people, you know, come to me crying and they’re like, well, I already threw it out. You know, you know what, instead, if you find it thawed or you find it in your car, put a big old X in Sharpie on that bag.

Throw it in the freezer, you know, come, come back to it after you’ve had a chance to calm down and assess what really happened and what the like real situation might be here. Okay. We’re moving colder now. Right? I’m taking you down to temperature gradient today. It’s getting warm in here.

Refrigeration. Okay. We do have like more than one study on this. Great. Time to celebrate. Well refrigerators are easier to regulate the temperature of then a cooler so I’m sure more researchers were like that sounds good. Thank you. Okay. So we’re looking at approximately four degrees Celsius or 39 and a half degrees Fahrenheit, ish.

So, what we’ve seen from study is that the bactericidal, or like a bacteria fighting ability of breast milk does decline somewhere around 72 hours of storage, just so you know. And studies have shown that milk expressed with low levels of bacteria at the onset are going to still be safe, possibly up to eight days in the fridge.

But depending on the front of the fridge or the back of the fridge or the door. We’re looking at about 40 degrees Fahrenheit. So how cold is your fridge? A lot of people can adjust that, right? Sometimes things freeze in the back of my fridge if I’m not careful about what I’m shoving in there. If your fridge is too full, it will not circulate evenly.

Yeah. So again, like, this is why we’re going to see the CDC say four days, right. Because four days is kind of going to be the time that, like that milk that is expressed in our worst-case scenario is going to go bad, right? Like you got dirty hands on a dirty pump and it’s in the door and, you know, little Timmy’s open it every five minutes.

I want to snacks. Mom, where’s the snacks? Timmy, that little asshole. You know, some kid dropped it out of the fridge anyway, but like that’s why those guidelines vary. Yeah. But if you think about it like that, that’s the CDC actually sounding pretty relaxed about it. You know, like they are traditionally a more uptight recommendation, you know, but if they’re saying like, even with little Timmy and your warmer refrigerator, that’s not circulating and it being four days and you pooped right before you frickin pumped. We’re still good at four days. It’s like, man, right. Then, then I totally believe that eight days in the back of the fridge with clean hands and no Timmy is going to be just fine. Yeah. Interestingly then as we get into these longer storage periods, we’re going to also start looking at milk composition changes.

Cause that’s a big deal. Or it might be if we studied it more. Yes. Some very limited study has suggested that. Of course. We’re going to look at lipase, everybody Episode 73 Lipase. Just go check it out. Some limited study has suggested for the most part lipase activity and lipid levels, aren’t going to be stable around like 96 hours.

But beyond that, we really start to see that increase in lipase activity and the lipids change. Lactoferrin which is a protein, those levels are going to be stable about four to five days. And immunologic factors are stable at least two days. So, okay. Freezing. The not great thing about this is we basically only have studies up to nine months for freezing milk.

Why? Who’s going to pay for that? Apparently is the question. But for the most part, the gist of these studies is that for up to three months, breast milk is going to be super safe and still nutritious. But after that, we start to see a pretty steep decline in lactoferrin and vitamin C and fats and proteins and all of that.

And this is in the freezer or a deep freezer? Any freezer. Okay. Yeah, we’re looking at about negative 18 Celsius or zero Fahrenheit. Which like my deep freezer is colder than zero, but my fridge freezers about zero. Okay. Yeah, but like for the most part, most of the macronutrients are going to be stable enough that like we’re comfortable feeding them to a baby up to nine months in storage.

Here’s the thing. We don’t have studies that go further than nine months and here’s the thing, does it matter because three months in baby land is a long time. Because I mean, if your baby’s three months old and you’re freezing stuff three months from now, they’re starting solid food. Right. But the bigger concern in that was cited here is like, then what are the implications for donated milk and, you know, babies that probably have some medical stuff going on if they’re getting donated milk. But for you in home use with your baby, don’t worry about it. That makes sense. Yeah.

Refreezing. Hot topic. Yeah. Guess what? This is where the ice crystal comes in. We don’t know. So the bacterial growth and the loss of antibacterial activity in thawed milk varies particularly based on the technique of thawing, the duration of how long it takes to thaw, the amount of bacteria in the milk at the time of expression. Again, how many times have I said that? Which is why you need to wash your hands. So basically ABM has declined to make a recommendation about refreezing milk.

Yeah. That’s very hard to study and I get that. Personally I have refrozen milk and then used it and I’m like, you know what, we’re just putting an X on it. I’m using it next time we feed the baby. Yeah, that way it doesn’t get lost. I mean, I guess again, do what makes sense. And you know, if it’s been accidentally thawed over, that means to me that the thawing has been a longer process, so maybe it’s been slowly thawing for 24 hours because somebody cracked their refrigerator door or the freezer door.

So in that case, I’m more likely to just shut the freezer door and be like, you’re probably fine. And here’s the thing with that last ice crystal magic. The only logical way I can make that make sense is that if there are still literal frozen crystals in there, it has to be a certain cold temperature.

You know, there’s not going to be ice crystals in 50-degree milk. It has to be at least 32, right? Yeah. Or like. You know, maybe most of the milk is at 33 and then like little, little pocket is 31. It’s still totally fine. Right. And when it’s that cold, the bacteria, good and bad, is moving really slowly. Yeah. Like it’s not moving fast enough to make a difference.

It goes from 32 and 33 and that’s like, wake up, wake up, eat and poop and take over the good one. Colonize. Anyway, insert infographic by Maureen about milk battling bacteria. My to do list gets longer. The last part of storing milk is mixing milk of different temperatures. I have an update because this paper from 2017 from ABM is now out of date on that.

The update is that we have seen several organizations, including the AAP change their guidelines based on new research that tells us that the overall bacteria count in milk is not changed when you mix warm and cold expressed milk together. And in fact, what does change that bacteria count is more containers used.

Yes. Yes. And this is exactly what we said in our episode with Lisa, where this right here is the number one reason that people waste milk or throw milk away. And you don’t need to do that anymore. So this is not just, you know, us telling you this. This is actually a public service announcement and they really should put this everywhere.

Every single medical professional that’s dealing with breastfeeding families should have a poster that says this because this is a huge deal. So say you have one ounce that you’ve collected in the haakaa already in the refrigerator and then your baby oversleeps. And you’re like, I’ll just pump. So you pump and it’s two ounces. So now you have to make a decision. Do I cool it down and then combine it and then lose all of that good fat on one side and the other side? You know, and then also it’s just like, is the bacteria. And then you’re like, I don’t know. So you freeze one ounce and then you freeze the two ounces and then it’s a pain when you try to send it to daycare.

Simplify your life, decrease your anxiety, put it all in one container in the refrigerator together. Mix the different temperatures together. And when you have enough volume, freeze it. For one feeding. Hooray! Or get that new Milkstache that Lisa made (enter promo code MILKMINUTE 15 FOR 15% off) that freezes your milk into tiny little half ounce cubes in a silicone tray that fit in both wide mouth bottles and skinny neck bottles so you can very accurately put together the exact amount that you need for each feeding, which is great. And again, lets you mix different temperatures, which is fantastic.

Okay, so where do we go from here? I don’t know. I’m getting kind of thirsty talking about all this milk storage. Well, before we go and drink some water, I’m going to say where we go from here is some people need to pay for more research.

Yeah. So, you know, if you know anybody with lots of money, they like to throw around for scientific research, breast milk is where it needs to go. We need more consistency in research as to how milk is expressed. You know, what storage containers, how long, hygiene protocols, you know, that kind of stuff is hard.

Like some of the papers I’m like cool, good conclusion, but we don’t even know if people wash their hands before they pumped. Right. Yeah. Like control for those variables and actually study it, how people are using it in real life. So like, oh, you’re using your husband’s 35-year-old lunchbox to cart your frozen milk back and forth.

Let’s talk about that with the dinosaur ice pack. Not saying it’s not going to work, I’m just saying. We need to know that. Yeah. Yeah. And we need to study the effects then frankly, of stored human milk versus fresh when we feed them to infants, not necessarily for the healthy term infant, but for our preterm infants and medically unwell babies that we’re feeding donated milk to.

And really the basis of all of this and why it’s so important to us is from like a moral standpoint, this research is going to make the lives of breastfeeding parents easier and make breastfeeding more sustainable for people that work outside of the home that require pumping. Because if we don’t, it’s just continually going to be one of those things that’s not fair. You know, it’s like, why does it have to be so effing hard? I mean, seriously, as of 2017, there is exactly one study investigating human milk after six months of freeze.

Like what, you know, and we like, and we know basic principles. Like food stored at certain temperatures is indefinitely good because bacteria can’t grow. Okay. We’ve got that principle then how do we actually apply it to feeding our babies? Right? And like, if your baby’s over a year old and you have milk still left in the freezer, you don’t have to throw it out because it’s been 12 months.

Right. You know, you shouldn’t have to, and it’s still valuable for your babies. So it’s not like the most nutritious milk you could possibly have anymore. Doesn’t matter. You’ve got a one-year-old who’s eating solid food. It’s still going to be something that they can have, you know? Right. And I just want to say the, I think the biggest thing that we need to happen is people need to agree on what unsafe milk actually is because that agreement doesn’t exist.

What it looks like, what it smells like and what the hard times are. Right. We have some studies that describe the degree of milk contamination over time, but none of them have a threshold for bacteria growth. And at which we should decide, like let’s not consume that milk because guess what? The baby’s got this GI system, that’s very acidic.

That’s gonna eat up any bacteria, which is why, like you can nurse on a breast that has an infection. Right. I mean, yeah, we just, we don’t have also like any definition of what adequate milk quality would be after freezing too. Like, you know, we have a couple of studies, but nobody has decided like, Hey, at this many parts per billion of bacteria, maybe we shouldn’t feed this to babies anymore.

Or like at this percentage of loss of macronutrients, this isn’t going to be sufficient for a primary food source anymore. And when we have babies that are relying entirely on frozen milk, we should know that. Which happens a lot, I think? And also how often is that happening? Like, we really need to know how many people are pumping and freezing regularly and how many babies are getting strictly freezer milk, because that’s not something that we know either. There’s so much unknown and lack of reporting and lack of caring to ask.

Yeah. So PhD listeners out there, if you wanted ideas for studies, there you go. And of course, if you want to support our podcast so we can outsource more stuff, so I can go get my PhD and do this research, you can get us and become a VIP at Boom Shaka Laka.

We need to give an award.

Have you ever been diapering your baby and just imagine all the diapers from that day alone being in the landfill? Doesn’t it make you feel a little bit guilty? Like actually every day. Yeah. And also, I just want to mention, I remember standing in the diaper aisle at the grocery store, wondering which diaper I should switch to next for my child’s persistent diaper rash.

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We have a very special award this week for our friend Caroline Brown Johnson. She is a member of the Breastfeeding for Busy Moms Group and she posted the best picture of her and her wedding dress breastfeeding her baby. And she says five minutes before walking down the aisle had to share with you ladies, eight months strong.

Ah, hell yeah. Way to go. I’m giving you the bad-ass bride award. The bad-ass breastfeeding bride award cause that’s awesome. Also way to choose a dress like you could pull a boob out of. Yeah, she’s got this gorgeous lace overlay with like a thicker strap. It looks like it’s probably a deeper v-neck, which I love. And also I used to work at a bridal shop, in case you didn’t know that about me.

Don’t worry about it. I have many different lives. I hear you. And she just slipped that strap down and is breastfeeding her sweet baby and her eyelashes are on point. Yeah, it’s all on point. Happy matrimony and happy eight months Caroline. You rock. All right. Well, thank you so much for listening to another episode of the Milk Minute Podcast and educating yourself on breastfeeding.

The way we change this big system that isn’t set up for breastfeeding parents is by educating ourselves and sharing with our children and our friends. Now, if you found some value in the episode, we produce for you this week, please go to, and show us your support with a small donation, which will grant you access to cool members only. Thanks everybody. This episode was edited and produced by Cherie Louise Turner, music by Lindsey Brett Carothers and Christian Higgins, transcript by Tiffany Goetz and social media management by Heather and Maureen. Thanks everybody. Bye-bye.

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