Reasons to avoid using a pressure cooker like the Instant Pot for making bone broths and stocks. Three safe, truly inert alternatives to consider instead. 
A common question for those who use an Instant Pot is whether it is safe for making bone broth or meat stock.
In my view, it is best to avoid pressure cookers for these types of dishes for two reasons, which I explore individually below.
Instant Pot for Making Broth
Stainless steel pots and pans and stainless steel lined appliances like the Instant Pot are fine to use for cooking with the exception of acidic foods.
Most people don’t consider bone broth to be acidic, but it most definitely is! Consider that if you make it the traditional way, apple cider vinegar is added at the start.
Stainless steel is often touted as an inert alternative to cookwares with questionable, dangerous non-stick coatings like Teflon that can pollute our air and our food.
However, even high-grade stainless steel (400 series) is far from being completely safe. Specifically, the metal ions from nickel, chromium, and molybdenum can end up in your food as well.
Metals in Stainless Steel
How much leaching is actually happening when you cook with stainless steel? It appears under certain circumstances a substantial amount!
According to the Journal of Agricultural and Food Chemistry:
After a simulated cooking process, samples were analyzed by ICP-MS for Ni [Nickel] and Cr [Chromium]. After six hours of cooking, Ni and Cr concentrations in tomato sauce increased up to 26- and 7-fold respectively, depending on the grade of stainless steel. Longer cooking durations resulted in additional increases in metal leaching, where Ni concentrations increased 34 fold and Cr increased approximately 35 fold from sauces cooked without stainless steel.
Cooking with new stainless steel resulted in the largest increases. Metal leaching decreases with sequential cooking cycles and stabilized after the sixth cooking cycle, though significant metal contributions to foods were still observed. The tenth cooking cycle, resulted in an average of 88 μg [micrograms] of Ni and 86 μg of Cr leached per 126 g serving of tomato sauce. Stainless steel cookware can be an overlooked source of nickel and chromium, where the contribution is dependent on stainless steel grade, cooking time, and cookware usage.
This leaching of heavy metals into food from stainless steel can continue even after years of use.
Cheap grade stainless steel would, of course, be even riskier.
For longer cooking and acidic foods, such as tomato-based sauces or slow simmering of bone broths and stocks, use alternate cookware! I use a Vita-Clay slow cooker, which is apparently more durable than the break-prone Instant Pots too!
MSG and Lost Nutrients from Instant Pot?
Another reason to consider avoiding pressure cookers for making bone broth is the potential for the creation of excessive amounts of glutamate.
While glutamate is not true MSG (which is its factory created mirror image), it will trigger a similar reaction in MSG-sensitive individuals.
Disclaimer: The glutamine levels in pressure cooker bone broth are as yet unknown.
In addition, how pressure cooking affects the nutrients in bone broth is also up in the air.
Here’s what Kaayla Daniel Ph.D., co-author of Nourishing Broth has to say about the effect of a pressure cooker on the nutrients in bone broth:
Pressure cookers seem to help achieve the gelatin we value so much. In terms of nutritional value, we have not done comparison testing of pressure cooker broth vs stockpot vs slow cooker. We’d love to do lab testing for a long lists of nutrients, but that gets very expensive very fast. If you know anyone who’d like to give us about $20,000 for a small study, we’d like to move forward with that testing. In the meantime, I see no reason for you to stop using your pressure cooker. However, we do question pressure cooking for 5 hours. I think most recipes say 1 hour though I’ve seen some recipes that recommend up to 3 hours.
3 Safe Options to the Instant Pot
In my view, the risk of heavy metals from Instant Pot bone broth combined with the potential for excessive glutamate and lost nutrients is a one, two, three strikes you’re OUT!
The best alternatives to the Instant Pot as well as stainless steel stockpots/crockpots for making bone broth are:
- Certified toxin-free clay pots (such as the Vita-Clay)
- Certified lead-free glass
- Old fashioned, ceramic coated stockpots
What About Nickel Free Stainless Steel?
What about the development of nickel-free stainless steel stockpots? These are fine to consider, but while safer than nickel ions in your food, chromium and molybdenum leaching remains an issue with these products.
One Hour Instant Pot Broth
One final point that is important to make.
Is the Instant Pot the only way you will ever make bone broth due to its speed and convenience? If so, then I would advise continuing to make it despite the risks.
Instant Pot bone broth is better than no broth! However, keep the cooking time as short as possible. No more than one hour would be best.
Thank you for this. I’ve switched to using my IP over my crockpot for some of the issues others mentioned in the comments and due to time and space. I’ve never gone over 50 min when making broth or stock and I definitely get a gel that I never got in the crockpot or on the stove. My MiL has a VitaClay but has never done broth in it due to it being too small and the time shut off. She works outside the home and restarting it isn’t an option. I’ll have to look into things for possible future changes but I appreciated the information. I’ll also be watching for the metal issues and checking into the ceramic pot someone else metioned for the IP.
This is so timely for me! After waiting for years, I was ready to buy an IP today.
The information about the VitaClay sizes is confusing. They say the VM7800-5C is 6 quarts. The measurements inside the pot are visible. Close to the top of the pot it’s marked as both 4.5 litres and also as just a bit more than 3 cups. 4.5 litres equals roughly 4.5 quarts, not 6 quarts. And 4.5 quarts is 18 cups, not 3 cups. I’ve noticed this mistake in the quarts-to-cups conversions with many of their other models as well. It leaves me wondering a bit about how well made the cooker is, if they repeatedly got this simple conversion wrong. But I’ll probably still give it a try.
Sarah, I thought i watched a video with your VM7800-5C in the background (although now i can’t find it). What volume will it hold? Thank you!
More questions (sorry!). If you don’t mind me asking: how many times has the clay pot in your VM7800-5C cracked, how long have you had it, and how often do you use it? After reading reviews, it seems replacing the clay pot when/if it cracks might just be part of the cost of using this cooker (but worth it).
I own 4 Vita-clays of various sizes and have used them for almost 5 years. I’ve NEVER had one break or crack. Note that those reviews you are reading are likely astroturfed by competitors. I don’t believe most reviews online, truth be told.
I think the difference might be what the pots hold in total (to the rim) versus how full you actually fill them with food (you don’t go all the way to the top).
Mason jars are similarly confusing.
If not stainless steel then what kind/brand of other cooking pans and pots for smooth top electric stove. Is the Cuisinart green gourmet skillet a safe choice?
I haven’t examined that particular model.
The Instant Pot is not ‘break prone’. I have owned three and only the oldest ‘broke’ after six years of extensive use.
You should be asking Instant Pot if it uses the best stainless steel, not just saying that something shouldn’t be made in it because of the ‘leeching’ of nickel and other metals that are not good for anyone.
Please re-read the article … even the highest grade surgical steel is leach prone according to the research. This is why medical equipment companies are coming out with nickel-free options.
What about cast iron? I use my insta pot to cook chicken. I also cook stock in my instapot, but as a slow cooker not as a pressure cooker. I would guess that is better than pressure cooker chicken stock.
Though knowing your thoughts on cast iron would help. I could find a pot to cook stock in.
Thanks for all the info!
Cast iron is fine if enameled. Plain cast iron presents an iron overload issue that for some, can be extremely serious. https://www.thehealthyhomeeconomist.com/the-health-hazards-of-cast-iron-pans/
My Vita Clay cooker only cooks up to 4 hours max. setting… do you have a model that cooks longer Sarah for longer broth cooking times? I think I may have cracked my clay pot once by continuing with successive 4 hours boiling cycles on it…had to buy a new one. I love it though. Thanks!
My model goes to 9 hours. It is simple to just reset if you wish to go longer.
What is a good alternative for doing large amounts for large families?
You can use a large stockpot (they come in 16 quart sizes), but be sure they are enameled.
If one uses an Instant Pot for broth and is concerned about stainless, they can buy a ceramic replacement pot for the Instant Pot. It’s $20 on amazon.
You mean I can buy a ceramic insert and pressure cook in it!! 🙂 I am an instant pot nut because its so easy and convenient for me to work with. Is ceramic safe or do I need to look for a special ceramic? are there toxin free ceramic cooking pots?
Hello;
Shoot. I can’t do slow cooker bone broths because I have Mast Cell Activation Disorder. So meat products that are cooked longer and not fresh are an issue for me and they become fiber in histamine the longer they are cooked. I
msg sensitive and haven’t had that reaction to the glutamate with bone broths cooked in the instant pot.
🙁 I’m sad now…
Did you read the end of the article? I have a suggestion there for those in your situation.
I too am histamine intolerant and cook my broths in an instapot. They turn out great and are filled with gelatin. There is no other way to enjoy the nutritious and gut healing benefits without doing it this way if you have histamine issues. ?
so you making stock in a stainless pot? I thought we wanted to avoid that? so confused.
I make stock in a Vita-Clay slow cooker (see picture in the post).