This Important Food Safety Instruction is often Missing in Cookbooks

This Important Food Safety Instruction is Often Missing in Cookbooks

May 30, 2017

I love cooking: the smells, the spices, the science... Making food and water safer to consume stacks right up there with the use of tools and fire as the oldest human experiments.

Turkey and Meat ThermometerEvery recipe is an exercise in biochemistry and every cooking tool or appliance was designed to take advantage of the principles of physics and engineering. Plus, whatever comes out of the kitchen is markedly tastier and safer to eat than what comes out of the lab.

The science of cooking at home is also a thousand times easier to access than what goes on in a lab. You can find all the reactants you need at the supermarket and all of the tools at any department store. Further, cookbooks and the Internet can teach you how to create every delicious dish ever conceived. 

These cookbooks, however, do not always provide the best food safety information. In fact, according to a new study from North Carolina State University, very few provide complete and accurate information on how to safely cook meat, seafood and eggs.

Ben Chapman, NC State agriculture professor and lead author of the study, read almost 1,500 recipes from 29 New York Times Bestselling cookbooks and found that fewer than 10 percent listed the correct method of ensuring those ingredients were cooked properly. The research was published in the British Food Journal.

According to the U.S. Department of Agriculture, cooking meat to a specific internal temperature for a specific amount of time is the only way to ensure that any contaminants, like salmonella or listeria, are destroyed. You can find those guidelines here.

Chapman and the researchers, however, found that only eight percent of the recipes they studied included any information about temperature, and a quarter of those had incorrect temperatures or resting times listed.

Stuffed Chicken BreastInstead, many recipes used other measures of doneness. In fact, 99.7 percent of the recipes, including those with temperature directions, included “subjective indicators” of doneness.

Most common among those was listing an amount of time that a piece of meat needed to cook, like cooking a steak for three minutes per side or a stuffed turkey breast for 25 minutes in the oven. Cooking time appeared in 44 percent of the recipes, but according to Katrina Levine, the paper’s lead author, cooking time is notoriously unreliable as each oven is different and the temperature of the meat going into the oven can dramatically affect how long it takes to cook.

Other recipes included the color or texture of the meat, like a fish recipe that calls for cooking until it "turns white and flakes." And if you read enough cookbooks, the phrase “until the juices run clear” is bound to cross your path.

Part of the reason so few recipes contain proper temperature instructions, could be that some recipes call for meat, fish and eggs to be undercooked intentionally. For example the USDA guideline for eggs is to cook until both the “yolk and white are firm.” By that guideline, every soft-poached, over-easy and sunny-side-up egg is in violation. Tartare, ceviche, carpaccio and sushi break the rules too.

That said, 10 minutes of recipe hunting on the Internet will show you a chicken or pork recipe without stating the proper temperature. Chapman, who has done similar research on burger restaurants, says that the temperature guidelines are the best way to keep food safe. So as we take advantage of the convenience of cooking in our own kitchens, this study shows that does not always guarantee the safest food, even if it does make the tastiest.

—Daniel Lane

Daniel Lane covers science, medicine, engineering and the environment in North Carolina.

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