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This worthy admonition understates its
cause. A more precise directive would be
that employees must wash their hands
correctly and thoroughly for 30 s or more,
use a nailbrush, and avoid touching faucet
handles, soap dispensers, and doorknobs.
Most of the bacteria found in
a kitchen are harmless. In fact, most
fecal contamination is harmless,
too. That’s why we can live in
a society “bathed in feces” and
survive. But every now and then
a pathogenic contaminant shows
up in the kitchen. Thorough and
consistent hygiene measures
prevent that infrequent visitor from
becoming widespread and causing
an outbreak of foodborne illness.
Sometimes crowded conditions
prevent you from using separate
kitchen space to carry out delicate
processing and handling procedures
that invite contamination. In
that case, isolate the procedures in
time instead. Don’t separate
cooked meat into portions right
next to another chef who’s butchering
raw meat, for example; pick
another time to do your portioning.
important when you are handling plant foods as it
is when you are preparing meat and seafood,
despite perceptions to the contrary.
Gloves can aid proper hand hygiene, but to use
them effectively you need to recognize their
limitations as well as their advantages. The main
advantage of gloves is very simple: people generally
take them off before they go to the bathroom.
That alone can make them worthwhile. Gloves
also keep food out of contact with bacteria in
pores or fissures in the skin, under the fingernails,
and in other areas that are hard to clean even with
proper hand washing.
But gloves aren’t a panacea. Wearing gloves over
filthy hands does very little good, because pathogens
on your hands can easily contaminate them
when you’re putting them on or taking them off.
You need to maintain proper hand hygiene even
when you’re wearing gloves.
You also need to change your gloves after every
trip to the bathroom and every task that involves
food products that could host contaminants. Yes,
that means the number and expense of gloves can
really add up, but no restaurant should be stingy in
handing them out. Issuing one or two pairs per
cook for an entire day is ineffective and creates
a situation that is ripe for hygiene problems. Dirty
gloves will quickly cross-contaminate other
kitchen surfaces, just as dirty hands would.
Be aware also of the surfaces most likely to be
contaminated, such as doorknobsparticularly the
knob or handle of the restroom door. It’s a good bet
someone who used the restroom before you didn’t
wash up perfectly, or at all, and that knob or handle
is the first place that person’s dirty hands landed.
Thus, the best hand washing job can be undone if
you grab the doorknob next; use a paper towel to
open the door, and discard it immediately after.
The same goes for water faucet handles: people
usually touch them before they wash their hands,
so they’re often filthy with microbes. That’s one
reason automatic faucets were invented. Faucets
with foot or knee pedals accomplish the same end.
Automatic soap dispensers are also a good idea.
Crowded kitchens with few sinks might also
benefit from alcohol sanitizers installed at every
workstation. This practice is becoming increasingly
common, but again, it’s important to understand
its limitations. Alcohol, for example, isn’t
always effective against viruses, such as the highly
infectious norovirus, one of the leading causes of
outbreaks of foodborne illness.
Kitchen Hygiene
Nothing in a kitchen stays sterile for very long.
Nearly everything is covered in bacteria, even if it
looks clean. According to Tierno, in fact, the two
dirtiest items in a typical house are both found in
the kitchen: the sink and the sponge. With so
many microbes in so many places, preventing
cross-contamination is a cook’s constant concern.
Another common hygiene offender in a kitchen
is the side towel. Many kitchens keep the same
towel hanging near a workstation all day. That one
towel wipes down counters, hands, and equipment
and soon accumulates a disgusting buildup of
food, bacteria, and yes, feces. No one would reuse
a dirty diaper without cleaning it, yet a side towel,
at the microscopic level, is just as revolting. The
difference is that we can’t see the teeming masses
of germs on a towel, so we imagine that it’s clean.
Side towels and dish towels should be used as
nothing more than potholders. Change them
regularly and launder them frequently. For wiping
hands and other surfaces, restaurant chefs and
home cooks alike should switch to disposable
paper towels. Although they’re more expensive,
they’re also far more hygienic.
Use a hygiene strategy for everything in the
kitchen, not just hands and towels. Clean all
cooking implements, equipment, and surfaces
thoroughly and regularly: knives, pots, pans,
spoons, spatulas, blenders, cutting boards, counters,
and storage containers are just a few examples.
A hot, sanitizing dishwasher is good for most small
kitchen tools and containers or household utensils,
dishes, and pans. Be sure that the dishwasher’s
temperature is high enough and that it does not
run out of cleaning solution or detergent.
For many kitchen surfaces and tools, a dilute
chlorine solution makes a great sanitizer. Household
bleaches such as Clorox are 5.25% solutions,
or 52,500 parts per million (ppm). Mix one
tablespoon of Clorox per gallon of water (about
4 ml of bleach per l of water) to yield a solution
that is roughly 200 ppm.
Make sure the bleach solution comes into
contact with every surface of every container or
utensil for at least two minutes. That may mean
T H E TECHNOLOG Y OF
The Telltale Glow
How can you tell if you’ve washed your hands well enough?
One of the best ways is to cover your hands with lotions or
powders that fluoresce under ultraviolet (UV) light but are
otherwise invisible. Apply the lotion or powder, wash your
hands as you normally would, and then check them with
a UV light. You may be amazed to find that your presumably
thorough hand washing leaves quite a bit of the UV lotion or
powder—and, therefore, many kinds of potential contaminants—on
your hands. Indeed, the primary value of this
exercise is to show people that their customary handwashing
routine isn’t as good as they think.
UV powder is also useful for tracking cross-contamination
in a kitchen. Dust some on whole eggs, for example, then
handle the eggs the way you normally would. Then check
around the kitchen with a UV light. Any place the powder
turns up is a place that Salmonella from the egg shells could
also be lurking.
A top biomedical researcher told us the story of a memorable
study he took part in while a medic in the US Navy.
During a routine on-ship physical exam, Navy doctors
swabbed some UV powder around the rectums of sailors
without telling them what it was. The next day the doctors
scanned the ship and its inhabitants with UV light. They
found traces of UV powder everywhere: on handrails and
doorknobs as well as all over the sailors’ faces. The results
literally illuminated the perils of poor hand washing.
A hand washed meticulously (below) shows no signs of UV
powder, whereas a hand lightly washed (left) clearly fluoresces
where the powder remains on the fingers and around the nails.
200 VOLUME 1 · HISTORY AND FUNDAMENTALS
FOOD SAFETY 201