Food Safety

It's time for the annual food safety lecture:

What should be said about food safety to this audience of seasoned home cooks?  Got to say something.  Well, the first two of three bottom lines are that bacteria need temperature and time to grow and give off toxins.  So, keep these numbers in mind:

· The “danger zone” wherein bacteria grow rapidly is 40ºF to 140ºF, with the highest growth rate between 90ºF and 110ºF.
· In four hours of accumulated time, in the higher end of the danger zone, growth of bacteria may occur.

Apply these data to a potato salad scenario for a charity affair and we have the following:
 

Event	Time the mayo is in the Danger Zone
Mayo is taken out of the fridge, mixed with Dijon mustard, diced olives, pickles, onions, lardons of bacon and whatever and set aside.	20 minutes
Potatoes are then peeled, cubed, boiled and set aside.	20 minutes
The eggs are hard boiled and set aside be sliced.	20 minutes
The potatoes and eggs, now cooled a little, are added to the mayo.
The salad—the cooked ingredients are now at about 90ºF—is placed in the fridge to await the trip to the charity event. It never cools to below 70ºF.	60 minutes
The salad is loaded into the car and makes the trip to the charity event where it is placed on the serving table just in time for the buffet—a two-hour affair.	60 minutes
There is a good crowd, but plenty of potato salad for the late arrivals.	120 minutes

Add up the time in the danger zone and we get 5 hours.  The late diners are at some risk from the potato salad!

The third bottom line is “cross contamination”—that is, the transfer of harmful microorganisms from one item of food to another by means of surface contact (knives, boards and hands) or storage and thawing in contact with other food items.  The villains here are pathogenic salmonella and E. coli, which are the source of most frequently reported foodborne infections. The heroes are space, soap, water and cooking temperatures.  Prepare and store raw meat separate from other products. Wash all vegies (Don't believe the "wash and ready" labels). Wash knives, steels, boards and hands with soap and hot water upon completion. Make sure poultry and processed meats (hot dogs and sausages) are cooked to at least 145ºF

Volume One of Myhrvold's Modernist Cuisine (see below) has three hugely informative chapters on the broad subject of Food Safety, all written from an in-depth perspective of solid science vrs. politics, gov't regulators, agenda activists and conventional wisdom. The chapters are titled Microbiology for Cooks, Food Safety and Food and Health. It's 158 pages of informed material supported with great photos and informative graphs. A seriously good read.