I have a confession: I love to cook. It's a combination of art and science, and you can eat the final product! My favorite aspect of cooking is food science and learning the processes that take raw ingredients and turn them into food, and I read a lot about modern and next gen cooking techniques. That's how I learned about and started using sous-vide.
Sous-vide is a cooking method like baking, broiling, or grilling. Food is placed into a vaccum-sealed bag and usually submersed in a water bath. The water is kept at a precise temperature using some type of heater/thermostat combination and the food is cooked by heat diffusion through the bag. The food cooked this way is not soggy, the flavors are sealed with the food, and extremely specific temperatures can be used. Most sous-vide is done with meat. Steaks can be cooked to a perfect medium-rare just by setting the temperature to the correct degree. And because the water, and therefore the food, never exceeds that temperature and no moisture is lost, food can be left in it for days without overcooking. The problem is most sous-vide cooking takes place between 120F to 150F; in the bacterial danger zone.
The theory behind preparing food safely is bacteria don't have a thermometer that kills them only if a certain temperature is reached. There are charts, graphs, and computer models that predict the death rate of certain food-borne pathogens, and the rate is a curve. Cooking chicken to 165F kills salmonella in a few seconds, but it take several minutes to completely kill at 150F. So theoretically, as long as you let food sit in the water bath long enough, it will pasteurize it and be as safe as conventional cooking, while being juicer and more tender.
However, most models for recommended cooking times do extend into the low temperatures that sous-vide uses. Many publications exist, but few actually link scientific or regulatory reports for the cooking times. Here is a page from a popular sous-vide immersion circulator company that lists times and temperatures, but the only source is a link to the FDA homepage. Most cooking times are based on the old models for high temperature, so the temperatures are not approved by food agencies. But the Institute of Food Research in the UK and the USDA/FDA have both begun programs to update the current models to include low temperature cooking.
I personally don't have a problem with sous-vide and have made several meals at home without any problems using the times provided from other chefs, as have many other people. I will continue to use sous-vide as an alternative cooking method and use safe food-handling practices when cooking to keep the risk for contamination low.
Douglas Baldwin: A Practical Guide to Sous Vide Cooking
Institute of Food Research Bacterial Growth Model Study pdf
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