Presence of fecal coliforms does not mean “there’s poop here”, but for aspiring poop-hunters is there an alternative?

Image created by Austin Bouck. Dear god let there be no egregious mistakes…

Recently a podcast I often listen to has discussed several articles with a similar note in their conclusions.

Nearly half of the 90 beverages from soda fountain machines in one area in Virginia tested positive for coliform bacteria — which could indicate possible fecal contamination

The study, conducted over six months at six licensed day-care centers in California, found high levels of coliform contamination, particularly in kitchen areas and on the hands of day-care workers. Coliform bacteria are transmitted through feces.

But recent reports reveal that the coffee or tea you’re sipping  – and even the cash you used to pay for it –  also carry bacteria found in feces.

Seven out of 10 samples of Costa ice were found to be contaminated with bacteria found in faeces.

40 percent of office coffee mugs contain coliform bacteria, which can be found in feces.

I don’t need to rehash arguments that have already been made here. Fecal coliform is a group of organisms historically used to identify whether drinking water could be contaminated with sewage or fecal material. Because it’s still a valid test to determine if water has been contaminated (they don’t survive forever in clean water, so if they’re present it’s because there’s a likely a failure in the system), the CDC and tons of state regulations still falsely state that these organisms are only found in fecal material.

Part of the issue is that coliforms as an indicator in general were extrapolated to environmental samples and food. NACMCF summarized the most recent scientific conclusion:

…whether coliforms, fecal coliforms, Enterobacteriaceae or E. coli. Kornacki and others (Kornacki et al., 2013) provide an historical evaluation of these criteria for foods and their utility based on current knowledge. None of these criteria accurately and consistently reflect fecal contamination of raw and processed foods nor are they useful or reliable as index organisms predicting the presence of pathogens.

The Kornacki reference is from the Compendium of methods for the Microbiological Examination of foods, which while expensive is an excellent reference for any food micro lab:

The debunking of the coliform=feces absolute conclusion was well covered by Doyle and Erickson in 2006, and more recently some thoughts were posted by barfblog.

But I’m writing this post today because I have a follow up question,

How exactly would someone actually test for fecal material?

Apparently, this is actually a problem in forensics, as an article published as recently as 2013 stated”no sensitive and simple fecal identification method using molecular biological techniques has been reported.” (Nakanishi et al., 2013). Here were the methods I was able to find with a cursory review of the literature.

1. Direct (macro) observation

A.k.a, the stain on the tighty-whities. Feces can be identified from it’s characteristic green-brown color from bile digestion and characteristic odor…this detection method isn’t really worth going into and I apologize for the mental image/odor.

2. Microscopy

Now we’re getting sciencey. Fecal material is a hodgepodge of various microscopic indicators. An experienced eye would be able to find bacteria (the bulk of the dry weight), but also undigested food particles and cellulose cell walls from plant material. Some epithelial and mucousal cells from the GI tract would also be visible. Interestingly, one way to determine if the fecal material was from a person or animal would be to look for excess hair in the sample, either from digesting prey or from grooming. The hair has to go somewhere, and I’m really curious if you would see a difference in hair mass between bearded and clean shaven men…

3. Chemical Indicators

Urobilinogen is a byproduct of bilirubin metabolism, and will be found in animals which consume meat and/or are otherwise digesting blood.  This appears to be a fairly classic test to discriminate fecal material from other bodily fluids like sweat or saliva and can be performed on site using a fluorescence indicator solution. Unfortunately, urobilinogen can also be found in urine since it is also returned to the kidneys for excretion.

4. Microbiological Profile

Well, crap. Here we come full circle. The most recent research on this subject seems to be using newer sequencing techniques to identify the unique organisms in the microbiome of feces. The goal is to find specific organisms or genes that would allow forensic scientists to discriminate between fecal material and other bodily fluids.

Here’s the thing though, none of the research identifies coliforms as a group of interest. It’s too broad and unhelpful! Rather than traditional “fecal bacteria”, the Bacteriodes genus has been identified as the predominant organism group in feces. Specific organisms identified were B. uniformis, B. vulgatus, and B. thetaiotaomicron. However, the state of California has specifically identified these organisms thriving in marshlands, yet still attribute them directly to feces. It would seem that again we can infer that fecal material is likely to contain these organisms, but it seems improper to assume that the presence of the organisms means that fecal material was the source.

I’d love to hear from some forensic scientists on what I got right and wrong here. From what I can tell from the literature it seems like there isn’t as much forensic interest in fecal material. The authors referenced how it is hard to isolate DNA due to interference from bile enzymes and microorganisms, which would reduce its value as evidence.

It seems like at this time a definitive test for “there is poop on this plate/ice/food/hand” doesn’t exist.

Much to the chagrin of PCRM, who would like us to declare the invisible feces on our meat.

Maybe we can just stop making the correlation between feces and food hygiene and instead focus on pathogen detection/prevention/pervasiveness as a means to evaluate foods on the market. While we talk about the fecal-oral route a lot, we’ve known for a long time that pathogens can be found almost anywhere if you start looking, so let’s look for them instead of fecal coliform clickbait (which this post totally is).



Resources for fecal identification forensics:

Drexler, Judith Z., et al. “Marsh Soils as Potential Sinks for Bacteroides Fecal Indicator Bacteria, Waccamaw National Wildlife Refuge, Georgetown, SC, USA.” Water, Air, & Soil Pollution 225.2 (2014): 1861.

Forensic Resources.Serology – Blood and other Bodily Fluids.

James, Stuart H., Jon J. Nordby, and Suzanne Bell, eds. Forensic science: an introduction to scientific and investigative techniques. CRC press, 2002.

Li, Richard. Forensic biology. CRC Press, 2015.

Nakanishi, Hiroaki, et al. “Identification of feces by detection of Bacteroides genes.” Forensic Science International: Genetics7.1 (2013): 176-179.

Virkler, Kelly, and Igor K. Lednev. “Analysis of body fluids for forensic purposes: from laboratory testing to non-destructive rapid confirmatory identification at a crime scene.” Forensic Science International 188.1 (2009): 1-17.

Zou, Kai-Nan, et al. “Identification of vaginal fluid, saliva, and feces using microbial signatures in a Han Chinese population.” Journal of forensic and legal medicine 43 (2016): 126-131.

Fur, Farm, and Fork awarded IFSQN Member of the Month

Me and the other person with the NPR donation mug can stare each other down now.

I’m proud to be awarded Member of the Month for March, 2017 over at the International Food Safety and Quality Network, a community of food professionals sharing knowledge about food safety, equipment, certifications, and support.

From their about page:

The IFSQN was founded in 2003 to provide food safety practitioners with an online platform for sharing knowledge and information and to enable collaboration on the effective implementation, operation and continual improvement of food safety management systems. Twelve years on this remains our primary goal. As food safety regulations continue to develop and third party food safety certification standards are mandated globally the importance of the IFSQN has never been greater.

The IFSQN website attracts well over 1,500 unique visitors every day and we also distribute the popular Food Safety Talk newsletter to over 25,000 subscribers each and every week.

Our discussion forums are unique and unrivaled anywhere in the world; with over 40,000 members creating an archive of over 80,000 posts as well as 1’000’s of files and documents to assist members old and new.

Each year we run the popular Food Safety Live online conference which brings together thousands of food safety practitioners for a free day of learning and in January 2015 we began running weekly complimentary educational webinars for our members.

If you work in food check it out, the forum archive has an amazing array of topics, and there are some very talented people on there helping out for free purely to help other manufacturers produce safe food. It’s like VIN for food professionals, and that’s pretty awesome.

I get a sweet new mug, courtesy of Safefood 360 ™ as my “trophy”. Will display proudly next to my “Where your hairnet” trophy.

Anatomy of a “Serving”

NFPIs it how much you’re expected to eat? How much you should eat? Pardon me, but if I want to eat an entire bag of potato chips, that’s exactly what I’m going to do.

I say this as the guy who helps create nutrition facts panels for food products for a living. I have read, reread, proof read, and colored red hundreds of these little tables in my time, and believe it or not, people aren’t lining up at parties to hear my thrilling stories.

I know!

Right now you’re thinking, “But Austin, I remember back in 2008 the FDA called 2,584 adults from the US to ask them questions about their diet. And 24% of the respondents said they had no idea if serving sizes were determined by government rules or by manufacturers.”

Your oddly specific observation would be correct, and I should have at least ¼ of the room hovering around me in rapt attention, waiting for me to clarify this confusing point. Time has shown however that everyone is clearly too intimidated to approach and ask the simple questions, even when I’m subtly firing off labeling trivia from the empty cracker box carelessly left by the cheese platter, or establishing my mastery of the dance floor.

Fact: Every party has a dance floor, here’s the label. dance floor Well let’s clear this up right now while I’ve got you at home/work/somewhere, on your computer/phone/tablet (scary that I know where you are, isn’t it?). Who determines serving sizes, manufacturers or the government?

Answer: The government!…ish.

Well that was unsatisfying, but it’s the most accurate answer I can give. Essentially what happens is that our government, via the FDA and FSIS (Food Safety Inspection Service), determine how serving sizes are to be calculated and presented, but also leave manufacturers options in specific situations.

So how are serving sizes determined?

Step 1, what are you eating?

he first step companies need to take when determining serving size is to determine what type of product they are selling. Back in 1993 when they had to decide all of this stuff, FDA determined that they could use data collected in the NHANES dietary surveys conducted in 1978 and 1988 to set these standards. These were nationwide surveys that collected all sorts of data, including nutritional intake and food frequency data. With this information, FDA created “Reference Amounts Customarily Consumed,” or RACC, for different categories of food.

The first step is easy, find the category that a food falls into, and look up the RACC used to determine the serving size in 21 CFR 101.12 (for non-meat items). For example, if I was making mashed potatoes, my category would be “Potatoes and Sweet Potatoes/Yams: Mashed, candied, stuffed, or with sauce” and my RACC would be 140 grams.

Step 2, how can someone measure it out?

Here’s where the variation begins! You might just want to use that 140 grams we saw above; however, not everyone has a scale in their kitchen, and let’s see you try to guess how much mashed potato makes up 140 grams. Can you think of the last time you weighed your food, much less with metric weights (provided you live in the U.S.)?

So at this juncture, the government instructs manufacturers to determine what the closest “common household measurement” to one RACC of your product is. So if we take 140g of our potatoes and see that that’s about 2/3 of a cup, our serving size becomes 2/3 of a cup!


Imagine we made a new, super fluffy mashed potato with more butter, and 140 grams of these potatoes actually wind up closer to ¾ of a cup. This means that even though both potato products were based on a RACC of 140g, they might have two completely different serving sizes, and the manufacturer arrived at each using the same government reference amount!

So there you have it, two serving sizes created based on a government standard, but completely different once observed on the store shelf. How could there be even more variation?

Single Serving

Ah, right. For many products, if the entire container contains less or near 200% of the RACC amount, then there are different rules to play by. In most cases, the product will be considered a single serving, but in others, manufacturers have the choice to label them as one or two servings. This is why you see different types of labeling in small containers such as ice cream, muffins, soda, and other “single serving” containers that appear significantly larger than the usual RACC amount.

As eaten, not as sold

Ah, and this is critical. When you ask someone how much cake they eat, they typically don’t respond with, “about 1/3 of a box of cake mix”. RACC values are based on products as they are consumed. However, serving sizes are based on products as they are sold. The reasoning? Because it would be bizarre to buy a bag of flour and see “two slices of bread” for a serving size. This makes more sense for some products than others, but ultimately serving sizes for products that require further preparation are the amount of packaged product it takes to make about 1 RACC of product as eaten. And remember, this must be rounded off at a common household measure!

Final thoughts

As we realize that our beloved nutrition facts panel is now old enough to drink (enforcement began in ’94), we look back and start to wonder if that data from the 70’s and 80’s used to determine RACC values still holds water. I can’t think of anyone who eats ½ cup of ice cream in a sitting, nor leaves the potato chip bag untouched after their first 10-20 chips.

But how about we think about RACC values in a different way. These values were never intended to be an expectation, but simply a way to bring nutrition information into context using consumer data. The thousands of calories in a 20 lb. bag of rice don’t have a lot of context when I eat it one bowl at a time, but that’s also not to say that I’ll never eat an obscene amount of rice in one sitting just because I’m starving.

Instead think of it this way, if these values are simply references to what we customarily consume at a time, we’ve got a great tool on our hands. I wouldn’t expect you to eat only ½ cup of ice cream, but have you noticed that many ice cream scoops happen to portion about ½ cup of ice cream at a time? And while I’ve been known to turn a bag of kettle fried chips into a meal, I still eat them one handful at a time, which just so happens to contain approximately 10-15 chips.

If only some sort of reference was available so that I could tell about how many calories I ate with each handful…

To learn more about how serving sizes are determined for all food products, check out the labeling and nutrition documents on the FDA website, this PowerPoint provided by the FSIS, or the Guide to Federal Food Labeling Requirements for Meat, Poultry, and Egg Products. Check out what consumer opinions of labels are looking like since 2008 in the FDA’s consumer research.

Choinière C. & Lando A. (2008). 2008 Health and Diet Survey, DOI:

Conrad J. Choinière, & Amy Lando (2008). 2008 Health and Diet Survey FDA Consumer Behavior Research Foos Safety Surveys (FSS)

Reference: Guide to cat colors and patterns

Whew, sorry for the delay in posts, I’m still working on that personal project that shall be revealed soon. In lieu of a research post this week, I thought I’d share a resource I’m using.

This Guide to Cat Colors created by deviant artist majnouna is an extremely detailed and easy to read chart describing the coloration terms and standards of the Cat Fancier’s Association. I’m using it to create standards for color that I’m using as one of the variables for my proposed research I’m hoping to get going by the end of this month. You can even buy it as a poster!

Regular posting to resume next week, thank you for your patience!

Reference: University of Illinois lactation biology website

In searching for information on mastitis, I came across this treasure trove of information. It was too good for me not to post here. It’s got great summaries, information, and a large collection of case studies. I almost wish the site itself was a book I could keep on the shelf, but for now I’ll just add it to my favorites. I want to recommend the page covering mastitis treatment and control for some light reading. It gives a really quick dirty rundown on industry methods and research. I was especially interested in the attempts to make vaccines, specifically ones for Staphylococcus Aureus, which can cause chronic infections that force dairy farmers to cull cows.

If you want to learn more about lactation biology, or are a student studying milk production, you need to visit this site and use it as a resource. Thank you to Dr. Walton Hurley for making your teaching materials available to everyone.


The Craigslist Hermaphrodite Chicken

That caught your attention, didn’t it? I’ve been watching Craigslist every day because I want to add two more chickens to my flock and if anyone puts them on there for free you’ve got to nab them quick. I haven’t had much luck since spring ended on nabbing free layers (roosters are a dime a dozen), but I came across this posting that made my jaw drop. Here’s the text for when the post is taken down.

Ameraucana chicken (albany)

Date: 2011-06-20, 5:54PM PDT
Reply to: [Errors when replying to ads?]


True hermaphrodite chicken
Bought at the state fair last year as the first place lavender ameraucana pullet

later laid a too large egg that damaged an ovary.. which became a testical…1 in 1000 chance
began to grow cox comb and spur buds.
still lays a nice greenish blue egg now and then but thinks she is a rooster which she now is also.(can fertilize other hens but not itself)
A chicken no one else you know will have! Beautiful coloring, again she won first in her class at state fair last summer.

Nice and my kids will miss very much but our primary rooster wins out. though they get along great and s/he’s a great conversation piece I can’t afford an extra chicken that doesn’t pull the weight it was meant for.

Bought for more but will sell for $20
email if interested
pic from when brought home from fair last sept. also the only chicken not afraid of dogs. will just peck at their noses till they back off

  • Location: albany
  • it’s NOT ok to contact this poster with services or other commercial interests


Yeah. I figured this guy was off his rocker. But, as I don’t really know all that much about chickens, I shot an email to my reproduction professor from last term, Dr. Fred Menino.

“Hi Dr. Menino,

I came across this craigslist ad that seems…like questionable information. I can’t see how any hermaphrodidic chicken would actually be a result of a “damaged ovary” and spontaneously become a fertile testicle. Espicially considering the other ovary is essentially non existant and he claims it still lays eggs. Are any of the claims made here possible in any way? Or is this guy completely off his rocker? I’d appreciate the insight or hopefully give you a laugh.”

He got back to me very quickly, and kind of blew me away.

“HA!!! Hi Austin!!! Good to hear from you!!!

This is like something you would read in the National Enquirer….BUT, believe it or not, there is a physiologic basis for some of the things this poultry entrepreneur is talking about!!! There is a phenomenon known as the “ambisexual versatility of the bird”…..I attached a link. I used to talk about it in ANS 316 but the poultry classes pick this up (I think?!) so I dropped it from my class.

Anyway, birds are weird………if you do certain manipulations to a hen (genetically female), you can alter her phenotype: 1) if you remove the left ovary before 20 days of age, the right ovary will develop into a functional testis and produce androgens and sperm. The hen develops rooster-like qualities but there’s no male ductwork leading to the cloaca!!! 2) if you remove the left ovary between 20 days of age and sexual maturity (18-20 weeks of age), the right ovary will develop into an “ovatestis”, an organ which has both follicles and seminiferous  tubules!! 3) lastly, if you remove the left ovary after sexual maturity (18-20 weeks of age), the right ovary will develop into a functional ovary, however, it will lack the oviduct to connect to the cloaca.

The question with this guy’s chicken is:  if the damage to the left ovary occurred before sexual maturity and an ovatestis developed, could sperm and/or eggs, as he suggests, be shed into the rudimentary oviduct that would be present?? I guess anything’s possible….maybe I should buy it and do a necropsy to see what the heck is going on??!!!!

Take care,


I had half a mind to take him up on that offer and buy the bird just to study it and assist in that necropsy. I wonder how the poster would feel about that, maybe I would leave that part out. This bird is just weird, super cool, but weird. The very idea of a sexual genotype producing a viable opposite phenotype is remarkable, and kind of breaks a lot of rules biologically. Though I’m sure there are dozens of similar or stranger things like this in the animal kingdom, but outside of weird marine life, I’ve never heard of anything like this before.

Here’s a wild sci-fi thought though, what if we could someday manipulate this so that we could breed chickens that are self-fertilizing, and would only produce gametes with XX so that we could create a self-cloning layer breed. Then we wouldn’t have to destroy all the useless males produced in our industry layer breeds! There would be a dangerous loss of genetic diversity within the stock, and they would be extra susceptible to being wiped out by disease or anything tailored to them, but the idea is exciting. No doubt they’ve tried it somewhere along the line. The real marketing question though, is that while animal rights groups would be (hopefully) satiated with no longer having to destroy male layer chicks, would the public accept and purchase eggs from genetically manipulated hermaphroditic birds?