Cheese: The GMO food die-hard GMO opponents love (and oppose a label for)


Slammed by critics, Chipotle has been forced to back track on its non GMO claims. Its beef, pork and chicken are sourced from farm animals fed with GMO grain. And all of its calorie-packed sodas are sweetened with GMO sugar.

But it has yet to come clean on its most controversial GMO ingredient: all of its cheese is genetically modified. That’s right. The clotting agent used to curdle the milk into cheese is genetically engineered. So much for Chipotle’s bragging claim of transparency.

In fact, almost all the hard cheeses made in the United States, and in much of the West, use a genetically engineered protein that is made from genetically engineered yeast and bacteria. That includes cheese made in Vermont, which has passed a mandatory GMO labeling bill–that curiously exempts its iconic Vermont cheese from carrying a GMO label. So much for the consumer’s ‘right to know.’

Critics of GMOs almost never acknowledge the fact that almost all hard cheeses are GMOs. In cheese production, coagulants called rennet are used to clot milk. The primary enzyme in rennet driving the clotting process is called chymosin, which acts on milk proteins like casein and makes milk curdle.

Traditionally, rennet is obtained from the fourth stomach lining of an unweaned calf. Calves have a higher amount of rennet in their stomachs compared to adults as they use it to digest milk, their main source of food. The rennet extracted from the stomach linings is usually a mixture of chymosin, pepsin (another enzyme) and other proteins.

Beginning in the 1960s, the price of rennet, a byproduct of the veal industry, rose and became less stable as the animal rights movement grew. Demand for cheese also soared, and cheese-makers began looking for alternative sources of rennet from plants and microbes.

Some plants and microbes naturally produce enzymes that have coagulating properties like rennet. However, rennet from these sources tend to produce other side reactions in cheese production, leading to undesirable results in taste.

So how did biotechnology come to play a role? In the late 1980s, scientists figured out how to transfer a single gene from bovine cells that codes for chymosin into microbes, giving microbes the ability to produce chymosin. These genetically modified microbes are allowed to multiply and cultivated in a fermentation process while they produce and release chymosin into the culture liquid. The chymosin can then be separated and purified. Chymosin produced using this method is termed fermentation-produced chymosin, or FPC.

FPC was given Generally Regarded As Safe (GRAS) status by the Food and Drug Administration in 1990 after 28 months of review. The FDA found that FPC was substantially equivalent to rennet produced from calves, thus it needed no special labeling or indication of its source or method of production. FPC is actually more pure than calf rennet, as it does not contain other proteins from the calf stomach lining that cannot be separated from calf rennet during production. “The real advantage is that it is probably a much cheaper way of producing this substance than to grow calves,” said William Grigg, an FDA employee.

Today ninety percent of the cheese in the United States is made using FPC. In the past two decades, FPC has been considered the ideal milk-clotting enzyme. FPC has been regarded as suitable for meeting vegetarian, kosher and halal requirements. However, some vegetarians consider FPC to be derived from animals as the microbes were genetically modified using bovine genetic material. In response, scientists began synthesizing the gene needed to produce a synthetic form of FPC that does not have any genetic material from animals.

GMO concerns about FPC are few compared to those directed at genetically modified crops. Recent campaigns in Vermont, a major cheese-producing state that just passed a GMO-labeling law did not address the use of FPC to make cheese; dairy products are simply exempt. FPC is not allowed in organic cheese based on the certification rules in the United States, Europe and Canada, providing an option for consumers who wish to avoid FPC.

FPC is an important but little-known success of biotechnology. Cheese-makers still use animal rennet, but to a large extent, FPC has removed the need for animal rennet in the production of cheese.

Jon Entine, executive director of the Genetic Literacy Project, is a senior fellow at the World Food Center Institute for Food and Agricultural Literacy, University of California, Davis. Follow @JonEntine on Twitter

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  • First Officer

    Interesting. Organic cheese requires the deaths of calves.

    • Maggotpunk

      Unless it’s derived from vegetable sources.

      • hyperzombie

        What vegetable source?

      • First Officer

        “… However, rennet from these sources tend to produce other side reactions in cheese production, leading to undesirable results in taste.” – from the article.

        • Maggotpunk

          You get a point for a non-sequitur. Congrats.

        • ZPT205

          The sentence immediately prior to the one (s)he quoted: “Some plants and microbes naturally produce enzymes that have coagulating properties like rennet. “

    • Schuyler Erlich

      That was my first thought as well.

  • mem_somerville

    Oh, it’s much worse–did you know that cheese-making fungi swap genes?

    I have tried to raise this with the EU, this unapproved cross-species gene swapping. I didn’t get much interest.

    • Eric Bjerregaard

      “I didn’t get much interest” I’m guessing that was no surprise.

  • Maggotpunk

    Since the GMO is removed during the process of the cheesemaking the cheese really isn’t GMO. That’s like saying the oxygen produced by a GMO tree is GMO oxygen, which it clearly isn’t. To get non-gmo certification the product can not have originally derived from any GMO even if the end product doesn’t have any GMO in it.

    So regardless of the propaganda, the cheese isn’t GMO, but it is amusing that the scientifically illiterate pro-GMO crowd has to go to such desperate measures.

    • There is no pro-GMO crowd here, just pro-science. As for your statement, there is no GMOs present in processed oils or in many GMO products. The fact is there is NO definition for GMO as it’s a made up term to describe dozens of different processes, functions and end points. If you want to talk about illiteracy, look in the mirror. That’s the point: It’s more ideology then anything else; it’s certainly not about science.

      • Jeremy Rawley

        EVERYTHING is “GMO” whether you like it or not. We humans have always loved screwing with nature and we made all the really big changes ages ago.

      • Maggotpunk

        A standard definition was set up and agreed to by the international community at the Cartagena Protocol for Biosafety. Funny how someone so “illiterate” was able to know that but you weren’t able to. Guess all the anti-science GMO crowd has is insults when they don’t have facts on their side.

        As for your claim about processed oils, the genetic markers for the transgenic organism is present in the oils which is seen in the altered acid levels in the end product, compared to the levels seen in the non-GMO product.

        I know, science, turn away while you can.

        • That’s just a silly argument, avoiding the reality that anti-GMO/anti-science activists use ideology and not science. Scientists do not agree on what GMOs are. Or haven’t you read documents from the National Academy of Sciences or the World Health Organisation or the European Commission? Or are they on your banned list as too scientific? In fact making GMOs is a complicated process and there is no logical/scientific reason to contend that Vermont GMO cheese is any different than many other GMO processed products. It’s a distinction without a difference. There is no traces of GMOs in “GMO Cheerios” either. There are no GMO markers in many products (including many oils by the way)–so if that’s your definition, you’re just flat out wrong.

          • Maggotpunk

            Ignoring the facts presented before you, typical of the anti-science crowd.

          • Eric Johnson

            The facts are simple. The oils do not contain GMO materials even if made with GMOs. A change in the molecular weight distribution may be caused by a GMO process, but that is not sufficient to claim it is a GMO material. All oils have a distribution of components that varies naturally. I the same thing by mixing individual components in the lab. No GMOs involved. Theree is no way to create a conclusive test method in this case.

          • Maggotpunk

            Yes, the facts are simple, that’s why I already produced the scientific research which contradicts your claim.
            Detection of GM soy in crude oil:

            And then detection in refined oil:

            As you say, the facts are simple.

          • Wackes Seppi

            So you can detect something even in
            refined oil, with great difficulty though if I interpreted the
            summary correctly.

            What is this « something »?
            DNA fragments from the RR gene.

            So what?

          • Maggotpunk

            Funny thing about the WHO, apparently they do have a definition of GMOs, they also reference the CPB. Then again, I’m illiterate so someone clearly more brilliant than I am already knows all this:

          • That’s the point maggot. Every organization has its own definition. Proved the point. Now go back to the Poliburo and get your next talking point.

          • Maggotpunk

            Actually, that wasn’t your point. For someone so literate you can’t even understand your own claims. You’d think with all the money your corporate benefactors have they could have hired someone with a bit more scientific literacy.

          • GaelanClark

            Yeah, what?….you wrote “The fact is there is NO definition for GMO as it’s a made up term to describe dozens of different processes, functions and end points.”…and now you go on and describe a definition all the while decrying that you “Proved the point.”
            What point? That your pecky little fingers click too fast or that you are wrong?
            One way or the other, both of those assertions are true.

            So, can you write what you mean? Maggot’s got you beat so far even though it seems you think you’ve “Proved” something.

          • Wackes Seppi

            Funny definition by the WHO! Well, if
            you consider it a definition, in a FAQ page and with the word
            « can »:

            « Genetically modified organisms
            (GMOs) can be defined as organisms (i.e. plants, animals or
            microorganisms) in which the genetic material (DNA) has been altered
            in a way that does not occur naturally by mating and/or natural
            recombination. »

            So natural mutations are GMOs…

            Since all modern tomatoes have genes
            introduced through wide crosses with wild relatives, they are all

          • polka

            Learn English grammar or be seen as uneducated. You repeatedly fail to agree nouns and verbs. Reading your comments is taxing, e.g. “There is no traces…”, “there is no GMOs”, etc. Also, you are a terrible Mod — aggressive, argumentative, insulting. You should resign your post, as your belligerence and combativeness harm discussion.

          • Rob Bright

            Yes, Jon Entine is unabashedly pro GE/GMO. His talking points mimic almost word for word Monsanto’s talking points. He has nothing ‘scientific’ to say to help the discussion on GMOs and should probably just be ignored. (You can lead a human to knowledge, but you can’t make him think…)

          • Jon Albiez

            Where did Monsanto enter the argument? Whenever I see the word “Monsanto” in an anti-GM argument it’s usually followed by catchphrases such as “sheeple”. Heck, Monsanto isn’t even the largest proponent of GM technology! (DuPont claims that title)

            With current scientific evidence, there is no known evidence of harm from GM food or organisms. Could that change in the future? Hell yes. Anyone following the scientific method, when presented with clear, Repeatable evidence that’s rigorously cross checked by peers will change their views.

            Works both ways as well. Tobacco was thought to be safe, we all know it isn’t now. Saccharin was thought to cause bladder cancer until further testing revealed that was the case in creatures with alkaline urine such as rats – not humans. Science is dynamic like that.

          • Mike

            The tobacco industry fought tooth and nail to not have to label cigarettes. Just like Monsanto, Dupont, Bayer are spending millions to stop the labeling of GMO foods. If Science food is so good why are the not proudly waving the GMO banner? Like “Lite” and “Natural” they could say hey “GMO” and let us choose.

          • Rob Bright
        • Lynn A Kuntz

          Actually, not sure you know that much about lipid science, or you missed this “it is possible to monitor the GMO content at the first stage of processing crude oil.” Commercial oil goes through several steps, typically refining, deodorizing and blaeching. I suspect the first is pretty important to this conversation. If you do find any evidence it is or is not in thefinished oil, I’d love to know as I’ve asked that before and had differing replies.

          • Kevin Folta

            That’s always my point– the final product is refined away from any DNA, which is in aqueous fractions and does not associate with lipids. Can you detect something with PCR and 40 cycles? Maybe, but there is nothing there except for picograms of DNA. It really illuminates the point that you need to look at the product, not the process. The antiGMs are so bent on the process that they can’t see past it.

      • Rob Bright

        Jon Entine (aka Entoman) is definitely pro-GMO, and definitely not pro-science (unless you consider pro-industry science to be pro-science.) He is a shill for GE technology and active on many pro-GMO pages and sites. He is a troll for biotech and should be ignored. He has nothing useful to say and certainly does not rely on independent, evidence based science.

    • You mean like sugar from GM beets or oil from GM soybeans?

      • Maggotpunk


        • Neil

          Why not?

          edit: Oh, I see your reasoning below

    • JonathanNathan

      OK dude, what is the concern with GMO foods? As far as I can tell, it seems predicated on this notion that anything GMO is automatically dangerous in some way.

      • Maggotpunk

        I’m not grasping the relevance of your reply to my comment.

        • JonathanNathan

          You don’t like GMO foods. I’m just curious what your rationale is.

          • Maggotpunk

            Go troll someone else.

          • JonathanNathan

            Really. Asking you to explain your rationale is trolling.

          • First Officer

            TAS, Troll Accusation Syndrome, strikes again !

          • Rick McCallister

            If you can’t explain your concern, then why would anyone care what you have to say?

          • gmoeater

            Maggot, you use ‘troll” a lot.
            How about “respond” ?
            (if you’re serious about avoiding ad hominims, that is….. hmmmmm….. what you do says more you than what you say.)
            I’m sorry you’re so down on yourself, and that you see yourself as a maggot and a punk. So sorry.

    • gmoeater

      Uh, maggot …. you’ve just made an argument AGAINST labeling. The labeling measures ALL require sugar, made from genetically engineered sugar beets, to be labeled, tho the end product has NO ge material in it.
      Propaganda goes both ways, punk. (odd thing to call yourself, maggot punk; low self esteem issues much?)

      • Maggotpunk

        I really don’t know what’s more pathetic, that you’re trolling a year old post or that you have to resort to ad hominems. It just proves, once again, that the anti-science/pro-GMO crowd has nothing to offer. much like the article which things the DNA of cattle changes because they eat animal feed.

        BTW, the article is commenting on cheese, not sugar. Try reading the article, and my comment, before replying to either.

        • Eric Bjerregaard

          So, who just incorrectly answered a post on a year old article? The maggot of error.

        • gmoeater

          Maggot, the point is about your blindness to the end product in cheese, and slamming “gmos” in sugar. (Did I not make that clear to the readers? Others got what I was getting at.)

          I may be pathetic in your eyes, which is perfectly ok with me; or “trolling” (huh?) — but I have high self-esteem. You have some issues, as I pointed out, reflected in what you call yourself. Luckily, there are good, inexpensive therapists around to help you with your self-esteem issues.

    • FosterBoondoggle

      “the GMO is removed during the process of the cheesemaking”

      You’re referring to the fact that chymosin is extracted from the GM bacterial “broth”, right? How exactly is this different from extracting sugar from GM beets, cornstarch or HFCS from GM corn or, say, TVP from GM soy? The end product is a refined, though not 100% pure extract. Or are you claiming that, for some reason, chymosin can be extracted with zero contaminants while sugar from GE beets must necessarily be contaminated? Can you please spell this out?


      • Maggotpunk

        I’m amazed so many people instantly became interested in a post that’s over a year old. Apparently anti-science/GMO kooks travel in packs. Since the responses don’t appear to be valid inquiries I direct you to the largest manufacturer of enzymes who, like myself, acknowledge the enzymes aren’t classified as GMOs.

        Since I tend to defer to the actual scientists and am labeled anti-science I’m sure they’d appreciate commentary from the people here about how they are anti-science as well and will probably tire from responding to the same questions by attention starved internet trolls who spend their lonely hours searching for year old threads to post on.

  • From my understanding there is a non-GMO, non-animal version through a strain of Rhizomucor miehei.

    • That’s true but it’s not used nearly as much.

  • MikeB

    Kinda like insulin (Humulin).

    GMOs B cool!

  • disqus_zXLbNfw1Yi

    If they force labeling I’ll know which foods to boycott – the non-GMO foods!

    • gmoeater

      Bwaaa haaaa – me too! Very helpful to avoid sleazy food companies that label “non-gmo”! I found popcorn the other day in a “health” food store that said “non GMO.” I told the manager that, um, there IS no gmo popcorn to make a distinction with. She said, “Oh, those lables mean squat.” She’s right.

  • Tsandi Crew

    Too bad people here can’t state a supported, sourced fact with links to their sources without claiming everyone else is stupid.

  • Mike

    This is totally different than crossing slime bacteria with corn so they can spray Roundup on the corn. There could be good things done with BT but crossing in order to spay pesticides on a plant is different. Everyone, before buying this sites “pro gmo” spin go watch the movies
    “Food Inc.” and “Seeds of Death” to hear the other side of this topic.

    • gmoeater

      Oh, right. The “Reefer Madness” of movies, both of ’em. Other side, maybe; scientific, don’t think so.

    • First Officer

      You’re right. They should stick to Atrazine !

  • srgwriter

    Funny, in the mid 90s I started noticing that my system did not handle cheese as well. Wonder if this could be a reason. Obviously, these things will affect everyone differently, so my issue may not be someone elses.

    • Doug

      Hmm, I wonder if you got older at that time? Oh, of course you did, and everyone does. As you get older many different foods become harder to digest in particular oily foods.
      You probably only eat Velveeta anyhow.

      • srgwriter

        never eat that garbage. Uggh.

  • deedee

    I already avoid “organic” foods:

    • gmoeater

      Me too! Expensive, higher e.coli rates, and over-hyped.
      A local “health” food store has signs bragging that organic has “cancer-fighting antioxidents” that non-organic doesn’t have. They ought to be slammed by the BBB for claiming that.

  • Dan Lokemoen

    Well, since people who oppose GMO’s eat this without complaint, that proves that all GMO food is safe. (eyeroll)

    • gmoeater

      Nope. It proves they’re hypocrites, is all.

    • First Officer

      As safe as non-GMO foods!

  • gmoeater

    The exemption for gmo cheese was in Colorado’s initiative, too (which got soundly pounded into defeat by educated voters). The sponsors kept saying, when asked about this hypocracy, “Well, it’s a start.”

    A bad piece of legislation is bad public policy. It’s not “a start,” it’s a piece of junk.

    My gmo-hating friends just glaze over when I tell them that 90% of cheese sold has genetically engineered chymosin in it. Truth is inconvenient, sometimes.

  • Mickey Bitsko

    Very informative. Thanks.

  • You_Can_Block_Me_But_I’ll_Get

    Oh how I love bitch slapping hipsters with reality.

    Get a clue idiots! Things are done for a REASON in this world. You cant just make up sheet as you go along!

  • BGZ123

    Perhaps the most absurd objection to GMOs I have seen. And a major improvement to using calf stomachs! Please rethink your concerns, people. GMOs can be enormously beneficial.

  • nataly tejeda

    honestly i dont know .