Header graphic for print
Marler Blog Providing Commentary on Food Poisoning Outbreaks & Litigation

The Raw Milk Beat Goes On: A Look at the Literature and the 60-Day Raw Milk Cheese Aging Rule – UPDATE

It is great that the New York Times and Washington Post is following up on the research that I did several months ago. Since that post, I have updated (there have been a few more outbreaks and/or recalls). Here is the final that you can download.

Screen shot 2011-02-06 at 9.46.11 AM.png

  • aed939

    It would be good to see some evidence-based guidelines for raw milk cheese. I would like to see some standards based on a combination of factors such as acidity, moisture content, salt content, age, and testing or other conditions that are more sophisticated than just a 60-day rule. I know Quebec is doing some of this that enables raw milk cheese for less than 60 days age. So some formula or sliding scale combination would be good. Another option which I think is less preferred, is to develop safety standards for each type of cheese. This can limit creativity, so I would prefer standards across the board based on physical conditions universally applied across the board.

  • http://www.thecompletepatient.com David Gumpert

    What makes your approach so disappointing, Bill, is that you’ve gone and done some serious research to put this paper together. But then you fail to follow through in any kind of constructive way, except to pat yourself on the back, as if you were responsible for The New York Times and Washington Post putting out articles that are essentially trial balloons for the FDA to trash the minimum 60-day raw milk aging requirement. You refuse, for example, to suggest a logical followup study to compare the results for 2010 illnesses you document, to previous years.
    Actually, it’s not that difficult a study. I just did most of it–going back and examining 33 years of data on illnesses from raw milk cheese– in a few hours, and I report on it on my blog. http://www.thecompletepatient.com/journal/2011/2/6/the-one-question-the-fda-and-its-media-and-legal-apologists.html
    The reason my study didn’t take long is that there are very few illnesses to report from raw milk cheese. For your readers who don’t want to read my entire analysis, I’ll summarize, that over a 33-year period, 1973-2005, there were an average of two illnesses from raw milk cheese each year.
    As your paper suggests, there is little evidence of undue risk from raw milk cheeses. Indeed, there seems almost no risk. Yet you refuse to call the FDA to task to do the kind of basic assessment that should be undertaken before trashing this rule, and in the process likely putting dozens or maybe hundreds of raw cheese producers out of business…as well as depriving consumers of a safe, tasty and highly nutritious food. Why do you fail to push for the FDA to tell the whole story?
    David Gumpert
    author: The Raw Milk Revolution: Behind America’s Emerging Battle Over Food Rights

  • http://www.marlerclark.com/wmarler.htm Bill Marler

    David, I was responsible for the articles – I just was pointing out how lazy the media is. And, I am glad to see that you tout your own blog and book while complaining that I am doing what I do to pat myself on the back or for PR – pot calling the kettle black I am afraid.

  • Doc Mudd; shilling for common sense & the scientific method

    Remorse. I regret wasting the few mouse clicks to follow up on Mr. Gumpert’s “analysis”. The findings? Oh, there have been some poisonings over the years and those continue today, but so what, who cares?
    “…my study didn’t take long…” crows Mr. Gumpert, and I believe him about that much. His insistence that FDA should require endless study of the same simple dataset, should become mired in analysis paralysis, puts the eccentric spin on his rant. Perhaps, reasons Mr. Gumpert, if FDA stares at the record of poisonings long enough and intensely enough (as Mr. Gumpert & friends have) the numbers will all appear to fade into a meaningless smudge, no longer representing injured consumers.
    Every now and again one encounters a “study” that truly puts the ‘anal’ in analysis. Congratulations, Mr. Gumpert, once again you’ve outdone yourself as a analyst.
    Thank you, Mr. Marler for doggedly reporting the facts and keeping important food safety news from being swept under the carpet. Keep fighting the good fight.

  • http://www.davidgumpert.com David Gumpert

    Bill,
    Let’s forget for the moment about who’s promoting what or whom. What’s your assessment of the historical data about the public health threat of raw milk cheese? Does the record of illnesses from raw milk cheese over the last 60-plus years justify adjusting the 60-day aging rule so as to make raw milk cheese less accessible?
    David

  • http://www.marlerclark.com/wmarler.htm Bill Marler

    My point about the 60 day paper was to show that there really was no basis in reality in the 60 day rule, and that 60 days aging did not make raw milk cheese safe per se. I certainly thought it did, and I think most consumers did as well and some raw milk producers. Again, I am just trying to point out that food safety is important and beliefs need to be challenged. I am not sure what the right rule might be. Hopefully Bill Anderson can enlighten us.
    I think what you mean re CDC numbers is how many illnesses or deaths in any food product is acceptable – cheese, raw milk, hamburger or fugu – in relation to your level of risk or acceptance of your illness or other consumer’s illnesses? For me, perhaps zero is not attainable, but you have to understand my experiences with my clients over 20 years. I think we should do everything to reduce risk and simply not accept the numbers as acceptable.

  • http://www.thecompletepatient.com David Gumpert

    Appreciate the response. Just to clarify on your comment, “re CDC numbers is how many illnesses or deaths in any food product is acceptable – cheese, raw milk, hamburger or fugu – in relation to your level of risk or acceptance of your illness or other consumer’s illnesses? For me, perhaps zero is not attainable, but you have to understand my experiences with my clients over 20 years.”
    I wasn’t trying to suggest any number is “acceptable” (as Doc Mudd suggests as well) but rather asking whether the history of illness from raw milk cheeses constitutes a public health hazard worthy of a major change in the dairy regulations.
    You didn’t say if you thought the 60-day rule on raw cheese should be changed, though your posts have suggested you are sympathetic to the FDA’s inclination to change it. Are you?
    David

  • http://www.marlerclark.com/wmarler.htm Bill Marler

    Sorry if I misunderstood you on the risk issue. It seemed in the past that you used low numbers of ill as an excuse that things just are not that big of a deal. I must have misunderstood.
    On the 60 day rule. Honestly, before the Bravo outbreak, I thought the 60 day rule on raw milk cheeses meant something, and I think many consumers and producers did as well. From what I read and posted, the 60 day rule was and is completely arbitrary.
    David, I do not know if 30, 60 or 90 days makes sense. From what I have read, it is far more about how the raw milk cheese is made and the care that is taken in its manufacture – eg, Young Bill’s comments on certified WI cheese makers. The same is true for pasteurized cheeses and post pasteurization contamination.
    I think picking any date is arbitrary from what I have read and understood. I think picking any date is just a method of standardizing a point in time that might create less risk, but I would bet that all depends on the inputs and the care in manufacture.
    Does this answer your question?

  • http://www.thecompletepatient.com David Gumpert

    I should have known better than to ask a lawyer a yes-no question. :-)

  • http://www.marlerclark.com/wmarler.htm Bill Marler

    I’m sorry, did I not answer your question?

  • Doc Mudd; evil corp shill, etc.

    The pertinent “yes-no question” :
    Is the ’60 day rule’ adequate in every instance to protect the safety of consumers?
    _____ Yes
    __X__ No
    The correct response is “No”.
    No partial credit will be given for a response of “Yes”, or “Yes, except…blah, blah, blah”

  • Bill Anderson

    There are so many variables that affect the safety of cheese (regardless of raw or pasteurized).
    The most important thing for a cheese maker to understand is the pH/acid curve. This affects both food safety and quality.
    David is right here — cheese is a very safe food. Most outbreaks associated with cheese occur because of post-production contamination. Listeria, even if it is present in raw milk, is a very poor competitor with lactic-acid producing bacteria and will almost never survive the cheese making process.
    This is the reason that raw milk cheese is safer than pasteurized, because of the robust positive bacterial pressure present in raw milk cheese. Listeria cannot compete. Whereas in pasteurized milk cheeses which are reconstituted with a few monoculture strains, there is no where near the positive bacterial pressure as a raw milk cheese, and a pasteurized milk cheese is much more susesptible to listeria growth if it is contaminated post-production.
    I’ll say it again — cheese can have low levels of listeria and staph aureus and still be very safe. It is when the conditions are created that allow these organisms to grow to dangerous levels that they become a foodborne illness risk. The job of the cheese maker is to create the conditions which inhibit the growth of these organisms and promote the growth of the good guys (lactic-acid producing bacteria).
    Also, some varieties of cheese actually become MORE hospitable to listeria growth as they become older, because the pH begins to rise back to neutral. Changing to a “90-day” rule as FDA may propose, will only further increase the risk in these varieties of chese.

  • Minkpuppy

    I think the FDA would be foolish to make a rule based on 60 or 90 day aging alone. The standard should be set based on pH levels and other factors that make the cheese inhospitable to pathogen growth of any kind regardless of how long the cheese is aged. Aging time should be a standard of identity for the cheese, not a safety standard.
    Similar issues cropped up several years ago in fermented sausages and E. coli. Ultimately, the FSIS safety standards became based on water activity and dropping the pH of the sausage rapidly and maintaining pH at a level that would prevent the growth of E. coli 0157:H7 and other pathogens. The establishments must show through supporting documentation and validation studies that their water activity and pH levels are sufficient to control the pathogen and set their critical limits accordingly. The aging time became irrelevant from a safety standpoint but is still in place as part of the standards of identity for these products.

  • http://www.thecompletepatient.com David Gumpert

    Bill, to follow up belatedly on my Q and your answer, I asked the Q the way I did–should the FDA change the 60-day aging rule–for a reason. The FDA, given its antipathy toward raw milk in general, is unlikely to come up with rules that allow raw milk cheeses to be more easily available. Thus, once it begis fooling with the rules, they will almost certainly be to the detriment of consumers and producers of raw milk cheeses. So, while there is much wisdom in your response, it’s difficult to imagine them being codified in such a wise way.

  • http://www.marlerclark.com/wmarler.htm Bill Marler

    I tend to agree with you. I think any day rule is arbitrary. However, I’m not sure how a standard can be set given all the variables.

  • Bill Anderson

    I disagree with MinkPuppy.
    It is entirey possible to produce safe raw milk cheese that has a very slow acidification, and in the which pH begins to rise again as it ripens. One of the finest raw mik cheeses made in the U.S. is produced this way. The key rests in the milk itself. It is very very clean milk.
    Modern breeds of dairy cattle, who are bred for high production in a modern industrial ag setting, are less suited for raw milk production, and their milk (if it is to be used for raw milk cheese) will require a far steeper acidification curve to exclude organisms like Staph Aureus and E. Coli.
    However, trying to impose this kind of pH requirement on all cheeses will automatically exclude some of the very best varieties of cheese such as Mont D’or, Taleggio, and Robiola. When these varieties of cheese are made with milk from heritage breeds (bred for hardiness under more rustic farming conditions — aka pasture grazing — and for the richness of their milk as opposed to milk volume) they are very safe cheeses, despite the meager acidification.
    Bill M. is right about the complexity of the issue. Might I suggest the European AOC organizations as a model for dealing with this issue — AOC are voluntary regional standards that apply to a specific type of cheese. The AOC organization represents the producers, and negotiates the hygene and testing standards with the health authorities to meet the specific idiosyncrasies of their variety of raw mik cheese.
    You can’t seperate the agricultural practices from all of this, when you are talking about raw milk cheese. “One size fits all” is a recipe for disaster, but that is unfortunately what FDA is probably going to suggest.

  • Minkpuppy

    Bill A,

    I think you missed my point. If the acidity , or water activity or whatever of the product is what determines it’s safety, length of aging is irrelevant. Use the aging as a standard of identity but not the sole requirement to determine safety.

    If I understand you correctly, acidity is inhibiting the growth of the pathogens. It is possible to have slow acidification and still inhibit the pathogen if the acidity level is even slightly unfriendly to the bug in question. If you have to age it longer or shorter to reach your pH goal, so be it. But don’t tack a rule on there that says “Must be aged 120 days” and assume it’s good to go. You still have to prove that the acidification process has reached a sufficient point that pathogen outgrowth will not occur regardless of the breed of cow or type of milk that is used. You also have to be diligent in monitoring that acidification process so you can cut it off before the pH rises again to a level that allows growth.

    My guess is that there’s something fundamentally different about the chemical composition of the heritage breed milk you describe such as fat, sugar and protein content etc. that make it less likely for stuff to grow (in other words, it’s not good eating for bacteria). Even then, heritage breed doesn’t mean much if they’re crapping in the milk bucket. Still have to have good sanitation practices.

    To me, the cheese-making process will need guidelines somewhat like the compliance guidelines issued by FSIS. Appendix A and B are used by processors who are producing cooked products. The time temperature tables tell the processor how long to hold the meat at the internal product temperature listed on the chart to ensure that the pathogens meet the 6.5 to 7.0 log reduction in Salmonella (it’s also sufficient to kill other nasties). The processor chooses his/her critical limit from that chart and supports the decision with his cooking and cooling records. This allows for variation in prep techiniques for different types of meat products. Some products require low heat-longer time while others can be cooked to a high temperature quickly.

    It gets trickier with fermented meats but food science research was able to show that a minimum water activity and pH level needed to be reached for a safe product. How the meat processor reaches that goal is up to him/her. FSIS isn’t in the business of telling them how to make the sausage, it just wants them to make sure they hit minimum log reduction levels or inhibit the growth when they do it. Various processing aids like citric acid, phosphates, nitrates, sulfites etc and sodium content affect the water activity and pH as well and are accounted for in research commonly cited in meat HACCP plans.

    Why not a similar compliance guideline for aging and pH in cheese? Guidelines can be developed for the various different types of cheese you mentioned so it’s not a one fits all type solution. And they’re guidelines, not regulations which means they can’t hold it against you if your process still accomplishes the goal in a different manner. That’s where I see the problem–I know of FDA inspectors that have pet peeves about certain processes and will create hell for the plants that use those processes. That attitude has to be squashed.

    If FDA does HACCP like FSIS (and it probably won’t because they will most likely bastardize it in an even worse fashion), the processor can use diary science research data to figure in any other factors that affect pathogen growth and use that to support the cheesemaking process.

    Traditional methods can still be used as long as you show scientifically that your process is working to control the pathogens. ALL cheesemakers and dairy processors have to step up and insist on the posting of proposed rules and guidlines for comment.

    That being said, we need to eliminate this whole FDA-FSIS dual jurisdiction crap and let one inspector handle it all for those plants. Preferably, the inspector will be there more often than once every 10 years.

  • Bill Anderson

    Most soft-ripened and semi-soft ripened cheese reach about pH 8.0 at peak ripeness, and will hold out at that pH for a long time.
    This is what I mean when I say they become more dangerous as they become older.
    The pH curve of this type of cheese is a bell curve of sorts. The pH goes down to about 4.7 (sometimes over the course of several days or even weeks), and then begins to rise again.
    The really important pathogen control isn’t even the pH, though. That has more to do with product quality, flavor, and mouthfeel. The important pathogen controls are good hygene and sanitation, and robust positive bacterial pressure.

  • Minkpuppy

    Bill A.
    Hygiene and sanitation seems to be a big factor in the recent cheese recalls. The conditions in the reports make this old crusty meat inspector cringe. I recall one report where the workers were wearing their chore clothes (Iikely fecal-contaminated) to handle the cheeses without changing or at least putting on a smock or apron.
    I hate walking in to meat plants that aren’t properly maintained or cleaned. It makes a lot of work for me. I have to walk a fine line between making sure I document enough but don’t document so much that I overwhelm the plant or trigger a suspension unless it’s truly warranted.
    Would inoculations with positive bacteria help with the cheeses? I know sausage makers who use bacterial cultures to help ferment summer sausage and to me it’s the best tasting summer sausage in the world. :-)

  • Bill Anderson

    Absolutely. Positive bacterial pressure is the name of the game.
    A good cheese making room should SMELL like fermented milk, because the lactic-acid producing bacteria are so dominant.
    A cheese curing room shold smell like mold, yeast, and bacteria. There are literally hundreds if not thousands of beneficial varieties of molds, yeasts, and bacterias that grow on the surface of cheese.
    This is THE most effective way to control listeria. Listeria is a saprotrophic organism. It feeds on dead organic matter. The way to exclude listeria is to have LIVING FOOD!
    As far as E. Coli goes, that’s more a matter of hygene in milk collection and milk/cheese handling. Yes, I agree, its not a good idea to be handling milk and cheese when you are soiled with manure. Its not, however, neccessarily a bad idea to be covered in whey and milk… you are carrying the cheese culture around with you!