Stories like this really interest me, so a special thanks to Jody Lanard who sent it along. It’s about those gloves they wear while making you a sandwich at the deli or a fast food joint. You know the ones. The disposable plastic kind. Disposable so you can change them often and throw them away. The kind that prevent the hands of the person behind the counter making direct contact with the food. Those gloves.
From the Journal of Food Protection Volume 68, Number 1 p. 187-190, a paper by Lynch et al.:
A study was conducted to determine whether the levels of selected microorganisms differed on foods handled by gloved and bare hands at fast food restaurants. Three hundred seventy-one plain flour tortillas were purchased from fast food restaurants and analyzed for Staphylococcus aureus, Escherichia coli, Klebsiella sp., coliform bacteria, and heterotrophic plate count bacteria. Approximately 46% of the samples were handled by workers wearing gloves compared with 52% of samples with bare hand contact. Coliform bacteria were found in 9.6% of samples handled by gloved workers and 4.4% of samples handled by bare hands, although this difference was not statistically significant. The distribution of heterotrophic plate count bacteria, a general measure of hygiene, was also higher in samples handled by gloved workers in one restaurant chain. The presence of E. coli, Klebsiella sp., and S. aureus was detected in one, two, and eight samples, respectively, and there were no significant differences between samples handled by gloved or bare hands. Neither direct contact of the tortilla with the food preparation surface nor gender of the worker affected the level of any organism tested. The observed tendency of food workers to wear the same pair of gloves for extended periods and complacency might account for the apparent failure of gloves to reduce or prevent bacterial contamination. The results further suggest that glove use might be counterproductive because workers might wash their hands less frequently when gloved. (Abstract)
Here is some speculation on my part. Gloves protect the food when the organism is resident on the operator’s hands, for example, from a sore with Staphylococcus growing on it. One would think that gloves would also protect from contamination by unwashed hands, and maybe they do, but these data don’t show it. But hands are also able to carry pathogens from one source to another, pathogens from raw meat, say, bugs not normally resident on human hands. In those cases, bare hands might be better because they are a biological medium with many natural antimicrobial defenses built in. It is worth noting that some data suggest that H5N1 only lasts minutes on a human hand but for days on an inanimate hard surface in the environment.
This is another case where what makes sense intuitively might not really make much difference or might even be counterproductive. But some advice seems to be pretty good, even though I haven’t followed it. A couple of years ago I read a paper about the food safety practices of street vendors. You know the ones. You’re really hungry and it smells wonderful. When I lived in Manhattan I used to eat at them all the time (of course as Mrs. R. will be quick to point out, I’ve also gotten food poisoning a number of times). There are 4000 with licenses in Manhattan and who knows how many unlicensed ones. So I was especially interested in an article I found in Public Health Reports, “Safety of vendor-prepared foods: evaluation of 10 processing mobile food vendors in Manhattan” by Burt et al. (volume 118, pp 470-476, 2003). What these folks did was hang out around ten different carts and watch them unobtrusively for 20 minutes at a time. More than half the vendors handled the food with bare hands, just under half with bare or gloved hands that were visibly dirty, seven of ten stored cooked meat products at unsafe temperatures on non-heating or non-cooking portions of the cart during the observation period, and in four of ten carts raw foods were handled in ways that allowed them to contaminate prepared food being served. Several instances of bare or gloved hands coming in contact with the server’s mucous membranes with subsequent contact with the food were also seen.
For decades Mrs. R. has been telling me not to buy food from these vendors, advice she got from her mother (which made it suspect in my eyes, of course). And the stuff always looks so good, even better now than it used to. When I lived in Manhattan in the days of yore there wasn’t much variety: hot dogs, chestnuts, pretzels. Now it runs the culinary spectrum that includes curried meat dishes and rice, chowders, middle-eastern kabobs (“cooked” in front of you), various kinds of vegetarian dishes and much more. These foods are prepared and served away from running water, sanitary facilities, proper storage, efficient means of refrigeration and the usual kitchen appliances.If you add to this personnel untrained in proper food hygiene and a municipal inspectorate stretched thin by budget cuts, you have a recipe for numerous small scale disasters. You know the kind. First you’re afraid you’re going to die. Then you’re afraid you won’t.
Sometimes you should listen to your mother-in-law.