90% of North American cheese contains this secret ingredient!

The SECRET ingredient in your cheese! | Butternutrition.com
Do you know what’s in your cheese? Chances are you’re not privy to the secret ingredient that is NOT required to be listed on the label but is found in over 90% of North American cheese!

If you’re frustrated by this you’re not alone. You probably already know about that most dairy cows in the United States are fed GMO feed, but is there another GMO derived ingredient that could be contaminating even the grass-fed farm cheeses? The answer is sadly YES. Finding high quality GMO free cheeses is getting harder.

“What this means is that most cheese in North America is made from vegetarian-friendly but animal-origin, GMO-derived FPC rennet.” –American Cheese Society

All about rennet

Chymosin is the active enzyme found in rennet that is used as a coagulant in cheese-making. A coagulant is used to separate the milk into curds and whey, as well as break down the protein casein in milk.

There are 5 types of coagulants in cheese-making:

  1.  Animal rennet (most expensive, up to 2x times cost of alternatives)
  2.  Microbial rennet (mold derived rennet, hard to find, now replaced by FPC GMO rennet)
  3. FPC-Fermentation Produced Chymosin rennet (GMO)
  4. Vegetable rennet (hard to source)
  5. Citric acid or vinegar (often sourced from GMO corn)

Why is GMO FPC rennet used?

The answer is as simple as supply and demand. According to GMO Compass, “the demand for cheese cannot be met with traditional rennet. Therefore, diverse rennet substitutes are in use.” The FPC GMO rennet provides an inexpensive option in unlimited supply.

How can you tell if it’s in your cheese? It’s hard.

Companies are not legally bound to disclosing the type of rennet used on the label.

“FPC rennet is a genetically modified organism (GMO). According to the culture companies, 90% of North American cheese is made with FPC rennet. But ingredient labels do not distinguish between this type of microbial rennet and the original non-GMO type. And the fact that use of FPC-type microbial rennet is not labeled a GMO leaves those who oppose GMOs in the dark when it comes to choosing cheese.” –American Cheese society

What about imported cheeses from European countries that ban GMO’s and hence FPC is banned? According to this source, cheesemakers won’t use FPC for products distributed in GMO banned countries, but they will use it in products imported to the US!

According to The Non-GMO Project,  “If a cheese has our seal on it, the consumer can be assured that it does not have [bioengineered] chymosin.”  From my research, it appears that at this point “FPC is not permitted in USDA Organic Cheese.” (source), but that is being challenged.

What cheeses are safe?

The cleanest cheeses are those made with animal rennet, such as parmesan and those traditionally made without rennet such as ricotta and mascarpone. However if you need to be sure I suggest contacting the manufacturer, as citric acid and white vinegar can also be made from GMO corn.

“When the label says “enzymes,” it is likely that they are using one of the new products; lots of people are having serious intestinal reactions to commercial cheeses. Real animal rennet is still safe, as far as I know.” Ray Peat, PhD

This is sadly another example of how our current food system is dependent on GMOs. I prefer to vote with my fork whenever I can for the issues that matter—and GMOs is one of them!

What do you think? Does this concern you?

Pin it:
The SECRET ingredient in your cheese! | Butternutrition.com

Central Co-op. Rennet. 2013. Retrieved September 20, 2013 from http://centralcoop.coop/index.php?page=rennet
GMO Compass. Chymosin. 2010. Retrieved September 20, 2013 from http://www.gmo-compass.org/eng/database/enzymes/83.chymosin.html
Fifth Town Artisan Cheese. The Importance of Knowing Your Rennet. 2008. Retrieved September 20, 2013 from http://www.fifthtown.ca/artisan_cheese/editorial/the_importance_of_knowing_your_rennet/
Microsoft Office. Cheese  Clipart. Used with permission from Microsoft.
The Vegetarian Group Blog. Microbial Rennets and Fermentation Produced Chymosin (FPC): How Vegetarian Are They. 2012. Retrieved September 20, 2013 from http://www.vrg.org/blog/2012/08/21/microbial-rennets-and-fermentation-produced-chymosin-fpc-how-vegetarian-are-they/
Wikipedia. Rennet. 2013. Retrieved September 20, 2013 from http://en.wikipedia.org/wiki/Rennet

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  1. says

    I make a non GMO Goat milk caramel and I am having a hard time marketing it. My soap is also non GMO and not one person seems to understand how important it is to use non GMO soap. Your skin is the larges organ of your body and what you put on it is in your blood stream in 26 SECONDS. Thank you for posting this. Maybe it will open some people eyes to start searching for non GMO products

    • says

      Unfortunately people in my area don’t care much for health either. You may want to start selling on Etsy, or market to a more health conscious town. You could also have a small sign up with some GMO facts so they can see the importance! I sell all natural toothpaste on Etsy, but it’s not a popular product in my town!

    • Kandi says

      Never even thought about GMO soap, but that brings up a good point! It is bad enough many of us put chemicals on skin, but we really don’t think about our skin that much! I will be looking to see if my local markets have it available.

    • SaanenMom says

      My goats are fed local, non-GMO grains and I use oils, fats and butters that I try to get that are non-GMO. I do sell my soaps as “Natural” and have no trouble selling a 5 – 5.5 oz bar for $5. Any higher than that, they don’t sell. It doesn’t matter if the people are paying attention to what they eat or put on their body, our economy is NOT improving and people just can’t spend that kind of money ($7.50/gal unpasteurized milk) regularly. My soaps have been selling well, but the price can’t go up any, while my milk sales are slowing. My “job” as my husband’s caregiver keeps the goats afloat.

      • Tami says

        The whole conversation is about GMOs. They’re bad. She’s making a point that putting on your skin is just as bad as ingesting a GMO ingredient. A fact in which most people are ignorant.

      • SUSAN says

        DR Mercola talks about GMO soaps, shampoos, lotions, deodorant etc. GMOs Have paraban and other toxic ingredients in them. Dr Esinsteen, Dr Robert Scott Bell talks about it too. All on facebook or just research them. Your body is the biggest organ so it absorbs all this.

  2. says

    I get my cheese from Beyond Organic and am incredibly impressed with the quality. It is USDA certified organic, truly raw (aged 60 days), from cows that are raised STRICTLY on organic greens and of course raised without hormones, antibiotics, vaccines, etc. It is also from cows that do not have the A1 beta casein (“devil in the milk”) found in 99.9% of commercial dairy and even most raw organic grass-fed dairy. Pretty much all “raw” cheese you find in stores is still heated just below normal pasteurization, denaturing the proteins and killing the essential enzymes and probiotics. Just 1 oz of this cheese has 7 g. of predigested protein, 10 g. of healthy fat, probiotic, CLA, 200+ mg. Calcium, vit K2, and K7.

    Note: I will saw that because I am so passionate about healthy, nutrient-dense, organic foods, I have proudly partnered with Beyond Organic to be able to share their organic beverages, foods and skin care because they are products I use and believe in. You can become a Preferred Customer and become part of an exclusive buying club by purchasing these products at discounted prices to enhance your own healthy lifestyle or you can even share your passion for healthy living with others by becoming a Mission Marketer and supplement your income at the same time.
    Disclaimer: I will receive a commission if you purchase any products from my Beyond Organic website or enroll as a Mission Marketer through my website. I sincerely appreciate your support!

  3. Darcie says

    As a corn intolerant person, I’m unfortunately already aware of this rennet produced by fermentation. I can’t eat any of these cheeses, which is really sad. I miss cheese!!
    You’re concerned with GMO-free cheese, yet you mention soft cheeses being safer. Did you know that white vinegar and most citric acid used in food production is made from corn? As most of the corn used this way is GMO, I wouldn’t really consider these cheeses safe without checking the sources.

      • Darcie says

        This comment as a reply to mine makes no sense. Why would I want vegan cheese if I’m allergic to corn? I have to look specifically for cheeses made with animal rennet. :/

  4. says

    Shelburne Farms makes a non-GMO animal rennet grass-fed low temp cheddar. We switched, so some of the older cheeses still have it. Call for clarity.

  5. says

    As a former cheeseseller (and avid eater), this is disappointing. Personally, I fare well with any cheeses and tend to buy rather high-quality ones. It’s good to know that many of the imported cheeses, which almost always have animal rennet, are GMO free.

  6. Val Criswell says

    As a Real Foodie (I own a Real Food retail store) and hobbyist cheesemaker, I can’t believe this is a topic. I’ve used both Chymosin and Animal Rennet. The amounts you use in a batch of cheese are similar. The ratio is only a drop or two per gallon of milk. I’m a regular reader of your blog and enjoy the posts greatly. However, the petty nature of this is misleading and unrealistic. I find it hard to believe that anyone who understands the reality here is THAT puristic to care.

    • Val Criswell says

      I want to temper my reply above. I talk with women all the time who want to know how they can eat and serve their families better food. Since we’re all on a path and we don’t go from A directly to Z, its important to meet folks where they are and help them find the next step.

      Many of the women I talk to feel overwhelm and condemnation because they can’t find the time/energy/money to eat/serve at 100% Real Food level. I tell them to set priorities, and move to the next step. A post like this is counter-productive to those women.

      Now for folks who have allergy concerns, that’s a different perspective but the perspective given here is that grassfed cheeses are contaminated with GMOs which IMO, a few drops per gallon of milk is puristic and unrealistic.

      Just wanted to post with details for clarity… I’m not a hater or basher. :)

      • Robin says

        It isn’t necessarily about being puristic but voting with our dollars. Sure one drop in a couple gallons might seem minuscule, but when looking at how much rennet is needed to produce cheese for the American market, that is when it is not minuscule. Many of us strictly oppose GMO’s and by not supporting any product that contains it, we are lessening the demand which will in turn hopefully depress production.

    • Catherine says

      Hi Val,

      I have a background working in the food & cheese industry as well, which is how I learned about the “new rennet” years ago. While it may seem “puristic,” that’s not really what I’m after. More and more people are having reactions (digestive & otherwise) to dairy products, and all these industrial changes to tradition ways makes a difference, and I think the public should be aware of even the “petty” unknowings of the industry. Also I want people to know that they should experiment with different kinds of dairy to see if the cleaner kinds work for them.

      Thanks for reading and contributing!

      • Kandi says

        I enjoyed your post, and I agree that the public needs to be made very aware of how the industrial food operations work all the way down to the pettiest minute details. It is not puristic as Val had said. I myself want to know what it is I am consuming and how safe it may or may not be so that I may make an educated decision on whether or not I want to continue to consume a product. I love cheese though I have never made it, I think I might have to take a turn at it to see how I do. Thanks for the inspiration!

      • Emily says

        Is there any evidence in peer-reviewed literature that people have varying reactions to cheeses made with differing rennets?

    • Darcie says

      I care which ingredients are used, as I get allergic reactions to some rennets. Yes, even a drop or two per gallon. Trace ingredients make a difference, and if you’re trying to sell food to others, this is something you should already know.

    • Jen says

      This comment is disheartening. It’s like saying you won’t mind losing a few fingers because it’s just a minute part of your body. Lame.

  7. SaanenMom says

    Hoegger Goat Supply sells vegetable rennet as well as animal rennet: http://hoeggerfarmyard.com/xcart/Cultures-Rennet-Color/

    I would presume from what you said, that vegetable rennet is non-GMO. I get the 2oz and keep it the fridge, it lasts forever. I don’t make much cheese as I can only sell raw milk cheese and I HATE cooking. I do however make wonderful goat milk soaps, which I “cook” in the oven 😉

  8. Shawn says

    I’ve been researching cheese production recently and came across your website, one question, from what I’ve read so far the chymosin used in FPC rennet is not GM or GE. http://en.wikipedia.org/wiki/Chymosin
    “The genetically-modified microorganism is killed after fermentation and chymosin isolated from the fermentation broth, so that the Fermentation-Produced Chymosin (FPC) used by cheese producers does not contain any GM component or ingredient.”
    I know it’s wikipedia, and not all information their is accurate, but what do you think?

    • Catherine says

      I came across that in my research too, but regardless the FPC rennet is GMO derived, which is worth knowing.

      To me, it doesn’t matter if it is “technically” a GMO or comes from a GMO. It is the same in my mind, and by many in the food industry.

      Thanks for sharing!

    • Emily says

      This is correct, you’re not eating the organism just a byproduct it makes. Avoiding microbial rennet in favor of veal derived rennet makes no sense …just arbitrarily defining a food as “bad” based on a severe bias against biotech

  9. says

    It is true that it only takes a couple drops (about 1/16 teaspoon per gallon, depending on the type of cheese and strength of the rennet) but I try to avoid GMO’s altogether. I make all of our cheese (both soft and hard) from our 100% grass fed cow’s milk. I am very passionate about the ingredients in my dairy products and the diet that my cow eats. I use double strength organic vegetable rennet from New England Cheese-Making supply house.
    (Found here: http://www.cheesemaking.com/OrganicVegetableRennet.html )
    I have been very happy with the results from this particular rennet, even during extended aging periods (2 years or more). I am also very pleased with the philosophy of this company as they work very hard to provide truly pure ingredients (they even sell citric acid that is fermented so as to avoid hydrolization which produces MSG) and are very honest about their ingredients. If you’re trying to make non-GMO dairy products at home, I would check out this company first.

  10. Jason says

    Are we sure we prefer animal-derived rennet? It is derived as a by-product of making veal which is pretty rough from an animal rights standpoint.

    “Natural calf rennet is extracted from the inner mucosa of the fourth stomach chamber (the abomasum) of slaughtered young, unweaned calves. These stomachs are a by-product of veal production” http://en.wikipedia.org/wiki/Rennet

    GMO rennet is the same enzyme and the production process doesn’t hurt anything but the microbes that make it. I think eating animal rennet makes the world worse than eating GMO rennet.


  11. cliffageloff says

    There is no inherent danger in cheese made from FPC GMO rennet. Exactly what is “in” it that someone should not eat?

  12. kygal2009 says

    Yes, I am concerned. I need to stay away from animal rennet of any kind because I am a vegetarian. I also try to avoid GMO foods, so I am pretty much screwed unless I drive for over an hour to a specialty store such as Whole Foods, Trader Joe’s or Good Foods, etc.

  13. kygal2009 says

    GMO rennet is made from animal chromosomes. So, it is a form of animal rennet. I will commit to finding cheese made from vegetable rennet. I will have to go to stores like Whole Foods, Trader Joe’s, Good Foods, etc.

  14. Steve Levine says

    If the genetic modified cheese and dairy ingredients have nothing to do with increased usage of glyphosate, and if my purchase of the does not financially benefit Monsanto, I am less concerned. My avoidance of GMOs has less to do with human health, and more to do with environmental damage, species loss, and the arrogance of Monsanto.

  15. Emily says

    This is just silly. You would rather have cheese made by from a sliced open baby cow stomach than from a bacteria that was engineered to save the cow? You’re not even eating the bacteria, just the byproduct. Doesn’t even contain any of the GM bacteria DNA. This is a perfect example of a GMO you were already eating-with no issue- and solved a great Ag/food even ethical issue of killing infant animals and yet now you don’t like it because of a 3 letter label? If you’re going to be this strict your diet is looking more and more like orthorexia. Eat pizza at your kids birthday party. Eat cheese. Eat food. Be happy. Life is TOO SHORT .

    More info here: http://io9.com/you-can-thank-genetic-engineering-for-your-delicious-ch-1701156684

    • Mark says

      You are wasting your time. Reason and knowledge had no part in arguing these people into their opinions and so it can have no part in arguing them out. For them, being anti GMO is like a religion and is impervious to reason. They are like anti-vaxers and creationist. The difference is that you have a whole industry (organic food) stoking there irrational and unsubstantiated fears so that it can make more money.

    • Mark says

      Anti-GMO zealots cannot be reasoned with. It has become a sort of religion to them, impervious to facts and reason.
      And don’t think that appeals to their humanity will help either. So suckling calves have to die for them. Big deal. Because of their thus far successful effort to block GMO Golden Rice, 100s of thousands of children are needlessly going blind and dying from vitamin A deficiency every year. Leaders of there movement have actually sought to block famine relief efforts because food shipments would contain GMOs. Better that the starving die than risk the horror of GMOs. All of this without one documented case of a GMO harming anyone.

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