Pathogens, Bacteria and Salmonella
One large safety concern with sous vide that has been studied in great detail deals with the propagation of bacteria at various temperatures, especially salmonella. Salmonella only thrive in a certain range of temperatures, from about 40ºF / 4ºC to 130ºF / 54ºC, often referred to as the “danger zone”.
This danger zone is why we refrigerate our foods until an hour or so before we are ready to cook them. It is also why we cook our foods to specific temperatures before we eat them.
The biggest misconception about bacteria and the danger zone is that any food in the temperature range is not safe and as soon as you move above 130ºF / 54ºC the food instantly becomes safe. The truth is that the bacteria begin to die in direct relation to the temperature they are exposed to.
The best way to visualize this is to think about how we humans react to heat. We do fine in climates where the temperature is below 100ºF / 38ºC. However, once it begins to climb around 110ºF / 43ºC or 120ºF / 49ºC you begin to hear about deaths in the news due to heat stroke. If the temperature were to raise to 200ºF / 93ºC stepping outside for more than a few seconds would kill you.
Bacteria behave in the exact same way. They begin to die at around 130ºF / 54ºC to 135ºF / 57ºC and 165ºF / 74ºC just about instantly kills them. You can see this in the chart below, based on the USDA safety data
[13]
. At 136°F / 57.7ºC it takes about 63 minutes for your food to be safe and at 146°F / 63.3ºC it only takes 7 minutes to become safe.
This concept is why the USDA recommends that chicken is cooked to 165ºF / 73.8ºC, because at that temperature it takes only a few seconds for enough bacteria to die to achieve acceptable safety levels. In comparison, at 136ºF / 57.7ºC it takes 63.3 minutes at that temperature to achieve the same safety level, something that is virtually impossible using traditional cooking methods. Using sous vide makes it possible to heat chicken and other meats to an internal temperature of as low as 130ºF / 54ºC and hold it there long enough to kill the bacteria.
Please remember that this is assuming that your thermometer is exact and the water temperature is completely steady. I recommend always cooking foods at a little higher than the minimum temperature and a little longer than the minimum cooking time in order to account for any variance in temperature your equipment causes.
For more explanations of how this works you can reference the excellent guides by Douglas Baldwin or Serious Eats mentioned in our Resources chapter.
Plastic Safety
Another main concern of sous vide is cooking in plastic and whether or not this is a dangerous practice. Many scientists and chefs believe that cooking in food grade plastic at these low temperatures does not pose any risk. The temperature is about equivalent to leaving a bottle of water in your car, or in a semi during transport, in summer.
However, I find it hard to believe that we know everything about how plastic reacts to heat, water, our bodies, and the environment. As such, I encourage you to read up on the safety of plastic in sous vide and plastic in general and come to your own conclusions about the safety of using these techniques or consuming products packaged or shipped in plastic.
A
CHIOTE
B
EEF WITH
J
ALAPENO
P
OLENTA
Pre-Bath Time: 15 Minutes
Cooking Time: 1 to 2 Days
Finishing Time: 30 Minutes
Temperature: 131°F / 55°C
Serves: 4 to 6
Pre-Bath Ingredients
For the Roast
2-3 pounds chuck roast
3 tablespoons achiote paste
Pepper
Finishing Ingredients
For the Polenta
2 tablespoons butter
2 jalapenos, diced
¼ cup milk
2 cups chicken stock
Water as per the directions on the polenta package
1 ⅓ cups quick cooking polenta
2 tablespoon chopped fresh cilantro
Salt and pepper
Achiote is a richly flavored paste from Central and South America made from annatto seeds mixed with other spices such as coriander, oregano, cumin, and garlic. You can find it on the international aisle of many grocery stores. We pair it with a creamy polenta with jalapenos in it but you could also use mashed potatoes if you prefer.
Pre-Bath
Coat the roast evenly with the achiote paste then pepper it. Add the roast to the sous vide pouch then seal.
At this point you can store the pouch in the refrigerator for up to 2 days, freeze it for up to 6 months, or cook it right away.
Cooking
Preheat the water bath to 131°F / 55°C.
Place the pouch in the water bath for 1 to 2 days.
Finishing
Preheat a grill to high heat or a pan to medium-high heat.
Heat a pot over medium-high heat. Add the butter and melt. Add the jalapeno and cook for a few minutes until it softens. Add the milk, chicken stock, and enough water to bring the volume of liquid to the amount called for by the directions on the polenta package. Bring the liquid to a boil and then whisk in the polenta and cook, stirring, until it thickens. Remove from the heat.
Take the beef out of the water bath and remove it from the pouch. Pat it dry with a paper towel or dish cloth. Quickly sear the roast for 1 to 2 minutes per side, until just browned, then remove from the heat.
Portion the beef and serve it on top of the polenta.
C
ORNED
B
EEF
R
EUBENS
Pre-Bath Time: 10 Minutes
Cooking Time: 1 to 3 Days
Finishing Time: 30 Minutes
Temperature: 135°F / 57°C
Serves: 4
Pre-Bath Ingredients
2-3 pounds cured, uncooked corned beef
Finishing Ingredients
8 slices rye bread
8 slices swiss cheese
About 1 cup thousand island dressing
High quality Dijon mustard
1 cup sauerkraut
Corned beef cooked with sous vide results in meat with great texture and tenderness. It is also juicier and more flavorful than many corned beefs.
In this recipe we call for it to be cooked at 135°F / 57ºC which was the temperature we liked best. However, our test with the corned beef cooked at 146°F / 63.3ºC was also very good. It was drier than the 135°F / 57ºC meat but a bit more tender. Either temperature will result in fantastic corned beef.
Sometimes the corned beef will turn out too salty. If that is the case place it in a ziplock bag with some warm water and place back in the water bath. Over time the water in the bag will draw out the salt from the corned beef.
Pre-Bath
Place the corned beef in a sous vide pouch with any included spices then seal.
At this point you can store the pouch in the refrigerator for up to 2 days, freeze it for up to 6 months, or cook it right away.
Cooking
Preheat the water bath to 135°F / 57°C.
Place the pouch in the water bath for 1 to 3 days.
Finishing
Heat a pan over medium-high heat.
Remove the corned beef from the water bath and pat dry. Quickly sear it in the pan until just browned, about 1 to 2 minutes per side. Remove from the heat and slice into thin strips.
Brush one side of the bread slices with olive oil and toast until browned. Place the cheese on the un-toasted side of the bread and toast in a toaster oven or an oven with the broiler on until the cheese melts.
Add the thousand island dressing to four of the slices and the mustard to the other four. Pile the corned beef on the slices with mustard and top with the sauerkraut. Place the two halves together and serve.
B
OURBON
G
LAZED
P
ORK
T
ENDERLOIN
Pre-Bath Time: 15 Minutes
Cooking Time: 3 to 6 Hours
Finishing Time: 45 Minutes
Temperature: 135°F / 57.5°C
Serves: 4
Pre-Bath Ingredients
For the Pork
1-2 pounds pork tenderloin
1 teaspoon dried sage
1 teaspoon allspice
½ teaspoon ginger
Pepper
Finishing Ingredients
For the Glaze
1 cup bourbon whiskey
½ cup brown sugar
½ cup ketchup
2 teaspoons Worcester sauce
1 teaspoon liquid smoke
¼ cup apple juice
1 tablespoon lemon juice
1 teaspoon minced garlic
½ teaspoon cayenne pepper
¼ teaspoon dry mustard
Salt and pepper
This simple recipe takes a sometimes bland pork tenderloin and adds layers of flavor with the glaze. I usually sear the pork when it is just out of the refrigerator or at room temperature. This allows me more time to develop the glaze on it.
To save time you can also skip the step of reducing the sauce and just use it after you combine all the ingredients but the flavors will not be as strong.
Pre-Bath
Mix the spices together in a bowl. Pepper the pork tenderloin, sprinkle with the spices, then place in the sous vide pouches and seal.
At this point you can store the pouch in the refrigerator for up to 2 days, freeze it for up to 6 months, or cook it right away.
Cooking
Preheat the water bath to 135°F / 57.2°C. Place the sous vide pouches in the water bath and cook for 3 to 6 hours.
Remove the pouches and place in a ½ ice - ½ water bath until chilled. You can store the pouches in the refrigerator for around 2 days or freeze them for up to 6 months.
Finishing
Preheat a grill to high heat or the broiler in the oven.
To prepare the glaze mix together all of the ingredients in a pot over medium-high heat and bring to a simmer, stirring occasionally. Cook for about 30 minutes, until it thickens some.
Take the pork out of the pouches and pat dry. Sear on the grill until grill marks form on the first side, a couple of minutes. Brush the glaze on the side facing up and turn the tenderloin. Repeat several times until it is coated with the glaze, cooking about 30 to 60 seconds per turn.
Remove from the heat, brush once more with the glaze, slice into ½” rounds and serve.
S
T.
L
OUIS
S
TYLE
R
IBS