There’s no getting around it: Eggs are tricky to cook. The white and the yolk behave differently when subjected to heat. Because they contain different proportions of proteins, fats, and water, they coagulate and set at different temperatures, and they have different final textures. Plus, there’s the simple fact that the white of the egg is on the outside—closer to the shell and the heat source—and therefore cooks faster than the yolk.
At America’s Test Kitchen, we’ve devised countless ways to make egg cookery easier, from the quick timing of eggs poached in salted water with vinegar to hard “boiling” eggs in a steamer basket. But bringing sous vide into the equation changes things. Cooking eggs in a low-temperature water bath with a sous vide circulator allows you to cook with a precision absent from traditional methods. And with eggs in particular, this makes a huge difference.
Egg whites begin to thicken at 150 degrees Fahrenheit/65.5 degrees Celsius and fully set at 158°F/70°C, while the yolk begins to thicken at 145°F/62.8°C and fully sets at 180°F/82°C. “An egg soft-cooked at 60°C (140°F) is barely jelled throughout; at 62.8°C (145°F), the yolk is actually firmer than the surrounding white,” writes food scientist Harold McGee in the introduction to chef Thomas Keller’s Under Pressure, the first English-language sous vide cookbook. “Sous vide cooking has opened up new realms of texture and flavor that weren’t discernible before and that still aren’t fully understood.”
Because, really, egg cookery isn’t just about temperature. It’s also about time (see chart, this page). Sous vide cooking allows you, the home cook, to play with time in a way that’s impossible with traditional cooking methods, giving you the ability to decide exactly what texture you want, no need for winging it or guesswork.
However you like your eggs, one thing is clear: Each temperature degree difference is distinctive in sous vide cooking. “I can look at an egg at any point that’s been cooked low temperature,” says Dave Arnold, founder of the Museum of Food and Drink and author of Liquid Intelligence, “and tell you in this range exactly how hot or cold it was.” Arnold calls an egg cooked at 145°F/63°C for about an hour an “in-betweener egg”—not totally set but still creamy (perfect for serving on toast). Meanwhile, Dr. Michael Eades, co-creator of the SousVide Supreme water oven calls an egg cooked at 147°F/64°C for 55 minutes the “perfect custard egg”—a “soft white and a custardy, custardy yolk.” When developing our own recipe for Soft-Poached Eggs, we decided to go for a more traditional texture, one without any liquidy white. Our eggs are more like those you would expect to get for breakfast from the diner down the street. To achieve that, we cook our eggs for a far shorter time (12 minutes) at a higher temperature (167°F/75°C). (Bonus: Cook our sous vide Soft-Poached Eggs at the same time as our sous vide Hollandaise, and win brunch for a crowd.)
Eggs are perhaps the poster child for innovative sous vide cooking, but there is so much more you can do with this technique—even just in the breakfast realm.
Behold: sous vide Yogurt. After bringing milk up to 185°F/85°C, cooling it, and mixing it with a starter, we cook our yogurt in Mason jars in a low-temperature water bath for anywhere from 5 to 24 hours (depending on your preference for pucker). Using sous vide removes the need to babysit or monitor the temperature of the yogurt as it incubates—hands off! Sous vide also allows for easy homemade Ricotta, and even Crème Fraîche.
Want something a little more out there? Try your hand at our Runny Egg Yolk Sauce if you want the experience of a perfect runny yolk on your pasta, your salad, or your burger at literally any time—ready to go, straight from the fridge.
YIELD MAKES 1 TO 16 EGGS
Sous Vide Temperature 167°F/75°C
Sous Vide Time 12 minutes
Active Cooking Time 20 minutes
To Make Ahead Eggs can be rapidly chilled in ice bath for 10 minutes (see this page) and then refrigerated for up to 5 days. To reheat, lower eggs into water bath set to 140°F/60°C and cook until heated through, at least 15 minutes or up to 60 minutes. Crack into bowls as directed.
Why This Recipe Works Eggs are perhaps the poster child for sous vide cooking: The technique can produce eggs with unique texture; the method is hands-off; and the recipe is easily scalable. Typically, sous vide eggs are cooked at a low temperature (around 145°F/63°C) for at least an hour. This will give you a yolk that is slightly thickened but still runny and a barely set white. We found the white to be too loose when cooked in this temperature range, most of it running off when we cracked into the eggs. Some recipes call for cracking “63-degree eggs” such as these into simmering water to better set the whites. We wanted to ditch that extra step and still produce a perfectly poached egg, so we opted to cook at a higher temperature for a shorter time to set more of the white. This method produced a traditional poached egg—right out of the shell! And with the ability to make these eggs ahead of time—just reheat them in a 140°F/60°C water bath for anywhere from 15 to 60 minutes—this recipe is perfect for the brunch crowd. Be sure to use large eggs that have no cracks and are cold from the refrigerator. Fresher eggs have tighter egg whites and are better suited for this recipe. Serve with crusty bread or toast. Or for a crowd in Eggs Benedict.
1–16 large eggs, chilled
Salt and pepper
1 Using sous vide circulator, bring water to 167°F/75°C in 7-quart container. Using slotted spoon, gently lower eggs into prepared water bath, cover, and cook for 12 minutes.
2 Meanwhile, fill large bowl halfway with ice and water. Using slotted spoon, transfer eggs to ice bath and let sit until cool enough to touch, about 1 minute. To serve, crack eggs into individual bowls and season with salt and pepper to taste.
YIELD MAKES 1 TO 18 EGGS
Sous Vide Temperature 194°F/90°C
Sous Vide Time 20 minutes
Active Cooking Time 20 minutes, plus chilling time
To Make Ahead Eggs can be rapidly chilled in ice bath for 15 minutes (see this page) and then refrigerated for up to 5 days. They can be stored in their shells and peeled as needed.
Why This Recipe Works Hard-cooked eggs are a breeze to make with a sous vide circulator. Our goal: Hard-cooked eggs that were easy to peel, with a set but not fudgy yolk. We found that cooking eggs in very hot water (194°F/90°C) rapidly denatured the outermost egg white proteins, causing them to form a solid gel that shrank and pulled away from the membrane. This translated to easy-peeling hard-cooked eggs with set but not overcooked yolks. (When we tested cooking eggs at lower temperatures for longer time periods, the egg whites stuck to the shell membrane, making peeling a frustrating task. And once we got those eggs peeled, their yolks were fudgy instead of firm.) Using sous vide to hard-cook eggs makes scaling the recipe up or down simple; the method and timing is the same for 1 to 18 eggs. So whether you’re cooking a snack for yourself or preparing a large batch of deviled eggs for a party, this recipe has got you covered.
1–18 large eggs
1 Using sous vide circulator, bring water to 194°F/90°C in 7-quart container. Using slotted spoon, gently lower eggs into prepared water bath, cover, and cook for 20 minutes.
2 Meanwhile, fill large bowl halfway with ice and water. Using slotted spoon, transfer eggs to ice bath and let sit until chilled, about 15 minutes. Peel before serving.
YIELD SERVES 6
Sous Vide Temperature 167°F/75°C
Sous Vide Time 12 minutes
Active Cooking Time 35 minutes
To Make Ahead Soft-Poached Eggs can be rapidly chilled in ice bath for 10 minutes (see this page) and then refrigerated for up to 5 days. To reheat, lower eggs into water bath set to 140°F/60°C and cook until heated through, at least 15 minutes or up to 60 minutes.
Why This Recipe Works Eggs Benedict is easy enough for a restaurant to pull off, but even seasoned cooks grow anxious at the idea of tackling this multicomponent dish at home, especially when you want to prepare it for a crowd. Enter sous vide. Making our Soft-Poached Eggs with a sous vide circulator ensures perfectly cooked eggs every time. We developed our recipe for sous vide Hollandaise at the same temperature as our Soft-Poached Eggs (167°F/75°C) so that they can be made at the same time, in the same water bath. Presto! Add Canadian bacon and some quickly toasted English muffins, and you’ve got the brunch crowd covered. (Note: While our Soft-Poached Eggs can be made ahead, the Hollandaise cannot.)
1 Adjust oven rack to middle position and heat oven to 300°F/149°C. Place 1 slice Canadian bacon on each toasted muffin half and arrange on baking sheet; keep warm in oven.
2 Arrange 1 poached egg on top of each slice of bacon. Spoon 2 tablespoons (30 grams) hollandaise over each egg and serve immediately, passing remaining hollandaise separately.
YIELD MAKES 12 EGGS
Sous Vide Temperature 194°F/90°C
Sous Vide Time 20 minutes
Active Cooking Time 40 minutes, plus chilling time
To Make Ahead Hard-Cooked Eggs can be rapidly chilled in ice bath for 15 minutes (see this page) and then refrigerated for up to 5 days. They can be stored in their shells and peeled as needed.
Why This Recipe Works The best deviled eggs start with the best hard-cooked eggs. We use our sous vide circulator to make great hard-cooked eggs every time, plus the technique gives us the ability to make from just 1 egg to a whopping 18 (!) eggs without changing the recipe or cooking time. To make sure the eggs were both easy to peel and perfectly cooked, we opted to cook them in a water bath heated to 194°F/90°C. This higher-temperature cooking denatured the outermost egg white proteins, causing them to shrink away from the shell membrane. As a result, the shells easily slipped off of the cooked eggs. Fresh herbs, cider vinegar, Dijon, Worcestershire sauce, and cayenne elevated the flavor of the filling. This recipe can be doubled. If you prefer, use a pastry bag fitted with a large plain or large star tip to fill the egg halves.
3 tablespoons (38 grams) mayonnaise
1 tablespoon (4 grams) minced fresh parsley, plus 12 small whole parsley leaves for garnishing
1 teaspoon (5 grams) cider vinegar
1 teaspoon (5 grams) Dijon mustard
¼ teaspoon (1 gram) Worcestershire sauce
Pinch cayenne pepper
1 Peel eggs and halve lengthwise with paring knife. Transfer yolks to bowl; arrange whites on serving platter. Mash yolks with fork until no large lumps remain. Add mayonnaise and use rubber spatula to smear mixture against side of bowl until thick, smooth paste forms, 1 to 2 minutes. Add minced parsley, vinegar, mustard, Worcestershire, and cayenne and mix until fully incorporated.
2 Transfer yolk mixture to 1-quart zipper-lock freezer bag. Press mixture into 1 corner and twist top of bag. Using scissors, snip ½ inch off filled corner. Squeezing bag, distribute yolk mixture evenly among egg white halves. Garnish with parsley leaves and serve.
YIELD SERVES 4 TO 6
Sous Vide Temperature 194°F/90°C
Sous Vide Time 20 minutes
Active Cooking Time 25 minutes, plus chilling time
To Make Ahead Hard-Cooked Eggs can be rapidly chilled in ice bath for 15 minutes (see this page) and then refrigerated for up to 5 days. They can be stored in their shells and peeled as needed. Salad can be refrigerated for up to 1 day.
Why This Recipe Works For a creamy, flavorful egg salad with perfectly cooked eggs and just the right amount of crunch, we followed a few simple steps. First, we relied on our Hard-Cooked Eggs, which are cooked sous vide to yield creamy yolks, tender whites, and no green ring every single time. We chopped the eggs and then combined them with mayonnaise (our tasters dismissed cottage cheese, sour cream, and cream cheese), lemon juice, Dijon mustard, red onion, celery, and parsley. Be sure to use red onion; yellow onion will be too harsh.
¼ cup (50 grams) mayonnaise
2 tablespoons (24 grams) minced red onion
1 tablespoon (4 grams) minced fresh parsley
½ celery rib (40 grams), minced
2 teaspoons (10 grams) Dijon mustard
2 teaspoons (10 grams) lemon juice
Salt and pepper
1 Peel and chop eggs.
2 Mix eggs with remaining ingredients in bowl and season with salt and pepper to taste. Serve.
YIELD MAKES 1⅓ CUPS (260 GRAMS)
Sous Vide Temperature 167°F/75°C
Sous Vide Time 12 to 30 minutes
Active Cooking Time 25 minutes
To Make Ahead We don’t recommend making this recipe in advance.
Why This Recipe Works Hollandaise, one of the five mother sauces of French cuisine, is a brunch classic—and it can be a mother to make. It is an egg-emulsified butter sauce that is similar to mayonnaise in many respects, but must be kept warm to keep the butter fluid. There are a lot of ways to make hollandaise; the most traditional preparations involve a lot of time and temperature-sensitive whisking, double boilers, and stress that could ruin your mellow Sunday brunch vibe. Fret not, we’ve got you covered with this easy sous vide hollandaise. We started by making a quick reduction with white wine vinegar and shallots, which we then combined with egg yolks, butter, water, lemon juice, and salt in a zipper-lock bag. The short 12-minute sous vide bath at 167°F is conveniently the same time and temperature that we use to cook our Soft-Poached Eggs. Pulling off show-stopping brunch dishes like Eggs Benedict just got a whole lot easier.
3 tablespoons (40 grams) white wine vinegar
1 large shallot (30 grams), sliced thin
10 tablespoons (140 grams) unsalted butter
5 large egg yolks (85 grams), lightly beaten
¼ cup (55 grams) water
2 teaspoons (10 grams) lemon juice
½ teaspoon (3 grams) salt
1 Using sous vide circulator, bring water to 167°F/75°C in 7-quart container. In small saucepan, combine vinegar and shallot and bring to boil over high heat. Cook until vinegar is reduced by half, about 1 minute. Strain mixture through fine-mesh strainer set over small bowl, pressing on shallots to extract as much liquid as possible. Discard shallots.
2 Combine vinegar reduction, butter, egg yolks, water, lemon juice, and salt in 1-quart zipper-lock freezer bag. Seal bag, pressing out as much air as possible. Gently lower bag into prepared water bath until mixture is fully submerged, and then clip top corner of bag to side of water bath container, allowing remaining air bubbles to rise to top of bag. Reopen 1 corner of zipper, release remaining air bubbles, and reseal bag. Cover and cook for at least 12 minutes or up to 30 minutes.
3 Transfer mixture to blender and process until smooth, about 1 minute, scraping down sides of blender jar as needed. Serve immediately.
Variation
Add 2 sprigs (2 grams) fresh tarragon to saucepan with vinegar and shallots in step 1. Discard with shallots after straining reduction. Stir in 2 tablespoons (8 grams) minced fresh tarragon before serving.
YIELD MAKES ABOUT 1 CUP (200 GRAMS)
Sous Vide Temperature 149°F/65°C
Sous Vide Time 32 minutes
Active Cooking Time 20 minutes, plus chilling time
To Make Ahead Sauce can be refrigerated for up to 1 week.
Why This Recipe Works Chefs are obsessed with emulsions because they combine something that is already delicious—rich fat—with a water-based ingredient to create something even more satisfying (think mayonnaise, butter, and cream—all emulsions). And egg yolks are one of nature’s top-notch emulsions—a creamy mixture of water, protein, and fat (a full 34 percent!). We love a good runny egg yolk, and this recipe gives us the convenience of pasteurized, perfectly thickened yolks always ready to drizzle on toast, a burger, pasta carbonara, you name it. This recipe safely achieves pasteurization (144°F/62.2°C for at least 6 minutes) and then continues to heat the yolks to create a sauce with the ideal runny texture. Store-bought, in-shell, pasteurized eggs can also be used without any changes to the recipe. The cooking time depends on the number of yolks, so this recipe cannot be scaled up or down without making adjustments. Don’t discard the whites—save them to make recipes such as angel food cake or meringue cookies. You can also freeze them for later use.
12 large (200 grams) egg yolks
¼ teaspoon (2 grams) salt
1 Using sous vide circulator, bring water to 149°F/65°C in 7-quart container. Using spatula or ladle, push yolks through fine-mesh strainer into medium bowl; gently whisk yolks and salt until just smooth (do not overwhisk).
2 Pour mixture into 1-quart zipper-lock freezer bag. Seal bag, pressing out as much air as possible. Gently lower bag into prepared water bath until mixture is fully submerged, and then clip top corner of bag to side of water bath container, allowing remaining air bubbles to rise to top of bag. Reopen 1 corner of zipper, release remaining air bubbles, and reseal bag. Cover and cook for 32 minutes.
3 Meanwhile, fill large bowl halfway with ice and water. Transfer bag to ice bath and let sit until chilled, about 10 minutes. Transfer sauce to airtight container or squeeze bottle and refrigerate.
YIELD MAKES 4 CUPS (965 GRAMS)
Sous Vide Temperature 110°F /43°C
Sous Vide Time 5 to 24 hours
Active Cooking Time 1 hour, plus chilling time
To Make Ahead Yogurt can be refrigerated for up to 1 week; stir to recombine before serving.
Why This Recipe Works Making yogurt at home is a pretty simple process with delicious results, and it requires just two ingredients: milk and a starter (for this recipe we used a small amount of store-bought yogurt with live cultures). The live cultures—namely Lactobacillus bulgaricus and Streptococcus thermophilus—are beneficial bacteria that give yogurt the flavor (tangy) and texture (thick) that we love. It doesn’t hurt that these cultures are purportedly very good for you, too. First, we heated milk to 185°F/85°C to kill unwanted microorganisms and denature the proteins in the milk. This protein reconfiguration allowed the cultured milk to transform into creamy yogurt rather than separate into curds and whey. We learned that it was important to resist the urge to stir the milk during this heating process. As the proteins denature, they become loose strands eager to tangle with each other; stirring led to small lumps in the end product. We then cooled the milk to 110°F/43.5°C to create a friendly environment for the starter culture and to prevent curdling. We stirred in the yogurt starter, put the mixture into jars, and finally placed the jars in a water bath to incubate. The beauty of using a sous vide circulator for this process was that we could precisely hold our yogurt in the culturing temperature sweet spot without any babysitting. Five hours later, we were rewarded with delicious, tangy homemade yogurt. We found we could leave it for as long as 24 hours; the longer the incubation time, the greater the pucker. The success of this recipe hinges on using yogurt that contains live and active cultures. You will need two 16-ounce Mason jars for this recipe. Be careful not to overtighten the jars before placing them in the prepared water bath; that can cause the glass to crack. This recipe can be doubled.
3¾ cups (845 grams) whole milk
¼ cup (60 grams) plain yogurt with live and active cultures
1 Using sous vide circulator, bring water to 110°F/43.5°C in 7-quart container. Heat milk in large saucepan over medium-low heat, without stirring, until milk registers 185°F/85°C. Strain milk through fine-mesh strainer into 8-cup liquid measuring cup. Let cool until milk registers 110°F/43.5°C, stirring occasionally to prevent skin from forming, about 30 minutes.
2 Combine yogurt and ½ cup (120 grams) cooled milk in small bowl. Gently stir yogurt mixture into remaining cooled milk, and then transfer to two 16-ounce Mason jars and seal; do not overtighten lid. Place jars in prepared water bath, cover, and cook for at least 5 hours or up to 24 hours. Let yogurt cool at room temperature for 15 minutes. Transfer to refrigerator and let sit until fully chilled, about 3 hours. Stir yogurt to recombine before serving.
Variations
Line fine-mesh strainer with double layer of coffee filters and set over large bowl. Transfer completely cooled yogurt to prepared strainer, cover, and refrigerate until 2 cups (450 grams) of liquid have drained into bowl, 7 to 8 hours. Discard drained liquid.
Fruit-on-the-Bottom Yogurt Cups
This recipe will work with any variety of your favorite jam or preserves.
Substitute eight 4-ounce jars for 16-ounce jars. Dollop 1 tablespoon (20 grams) jam or preserves into each jar before transferring yogurt mixture to jars in step 2. Carefully pour off any liquid that has settled on top of yogurt before serving.
YIELD MAKES 2 CUPS (400 GRAMS)
Sous Vide Temperature 190°F/88°C
Sous Vide Time 30 minutes
Active Cooking Time 1 hour, plus chilling time
To Make Ahead Ricotta can be refrigerated for up to 5 days; stir to recombine before using.
Why This Recipe Works For those interested in making their own cheese, homemade ricotta is a great entry-level recipe. Ricotta is Italian for “twice cooked,” a reference to the traditional ricotta-making process of reheating whey, or the liquid left over from the production of other cheese, and then adding acid to coagulate the milk proteins. This method is called acid-heat coagulation. For our recipe, we started with whole milk and used distilled white vinegar for the acid. Distilled white vinegar, unlike lemon juice (the other common choice), is neutral in flavor and always contains 5 percent acidity. Heating the milk to 190°F/88°C denatured the whey proteins, allowing them to interact and coagulate with their casein counterparts. Using the sous vide technique for this process eliminated the risk of scorched pots and ruined batches of ricotta, a common problem when making it on a stovetop. Once the curds had formed, all that was left to do was strain them through cheesecloth. Cheese making has never been easier. Be sure to use whole milk; milk with other fat percentages will not work as well for this recipe.
8 cups (1.8 kilograms) whole milk
5 tablespoons (75 grams) distilled white vinegar
1 teaspoon (6 grams) salt
1 Using sous vide circulator, bring water to 190°F/88°C in 7-quart container.
2 Whisk together milk, vinegar, and salt in large bowl. Pour mixture into 1-gallon zipper-lock freezer bag. Seal bag, pressing out as much air as possible. Gently lower bag into prepared water bath until mixture is fully submerged, and then clip top corner of bag to side of water bath container, allowing remaining air bubbles to rise to top of bag. Reopen 1 corner of zipper, release remaining air bubbles, and reseal bag. Cover and cook until milk mixture fully separates into solid curds and translucent whey, about 30 minutes. If curds have not separated, cook for additional 10 minutes.
3 Remove bag from water bath and let milk mixture cool for 10 minutes. Meanwhile, set colander over large bowl and line with double layer of cheesecloth. Gently pour cooled milk mixture into prepared colander. Let drain, stirring occasionally, until whey has drained from edges of cheese but center is still very moist, about 30 minutes. Discard drained whey. Gently transfer cheese to now-empty bowl. Stir well to break up large curds and incorporate remaining whey. Cover and refrigerate until fully chilled, about 2 hours.
YIELD MAKES 1 CUP (265 GRAMS)
Sous Vide Temperature 96°F/36°C
Sous Vide Time 12 to 24 hours
Active Cooking Time 20 minutes, plus chilling time
To Make Ahead Crème fraîche can be refrigerated for up to 1 month.
Why This Recipe Works Crème fraîche is a cultured dairy product that is easy to make at home with a sous vide device. Traditionally it is often left to culture—for at least 12 and up to 24 hours—in a warm place. Culturing crème fraîche in a regulated water bath removes the need to manage (or worry about) the temperature of its surroundings during that critical phase. While yogurt is made by culturing milk, crème fraîche starts with heavy cream. For our recipe, we combined a small amount of buttermilk with pasteurized heavy cream, and then we placed this mixture in a warm water bath to culture for 12 hours. We strongly recommend using pasteurized—not ultra-pasteurized—cream for this recipe. Ultra-pasteurized cream is treated at a higher temperature before packaging and thus produces crème fraîche with a more muted flavor. Crème fraîche is a traditional accompaniment for luxurious caviar, or it can be served with fresh berries as an alternative to whipped cream. It’s a favorite cultured dairy product to stir into hot braises and stews because, unlike sour cream or yogurt, crème fraîche won’t curdle. Curdling occurs when cooking heat causes dairy proteins to denature and form clumps. The high butterfat content of crème fraîche (30 to 40 percent versus 18 to 20 percent of sour cream and roughly 4 percent of yogurt) protects against this clumping by keeping the proteins, which coat the many fat globules, further apart. Different brands of buttermilk contain different live and active cultures, which will produce crème fraîche with subtle flavor differences. Make sure to reserve some of the crème fraîche from your first batch to use as a starter instead of buttermilk for your next batch. You will need one 16-ounce Mason jar for this recipe. Be careful not to overtighten the jar before placing it in the prepared water bath; that can cause the glass to crack.
1 cup (235 grams) pasteurized heavy cream
2 tablespoons (30 grams) cultured buttermilk
1 Using sous vide circulator, bring water to 96°F/36°C in 7-quart container.
2 Combine heavy cream and buttermilk in 16-ounce Mason jar and seal; do not overtighten lid. Transfer jar to water bath, cover, and cook for at least 12 hours or up to 24 hours.
3 Transfer jar to refrigerator and let crème fraîche sit until fully chilled and thickened, about 24 hours. Stir to recombine before serving.
Key Points
• Sous vide cooking is very safe thanks to its precision and control
• We cook most food at or above 130°F/54.5°C to reduce risk of harmful bacterial growth
• If cooking below 130°F/54.5°C, we sear meat before putting it in the water bath to kill surface bacteria
• It’s important to rapidly chill foods if you’re planning to keep them in the refrigerator
• Don’t sous vide raw garlic
So you’ve bought a sous vide circulator. You’ve come home from the grocery store with two nice steaks and some high-quality plastic zipper-lock bags. You heat up the water bath to 130°F/54°C. You’re ready to put the steaks in the bags and then into the water bath and walk away for a couple of hours. But then you stop and you think, “Is this really safe?”
Sous vide relies on cooking at low temperatures, often for long periods of time. But when it comes to temperature and time, what is safe?
Food safety is top of our minds, too.
“I believe sous vide is significantly safer than most cooking methods,” says Douglas Baldwin, a mathematician at ChefSteps, a Seattle-based food and technology company. He spent months creating pasteurization charts for his own book, Sous Vide for the Home Cook. “It’s so much more predictable.” But there are a few things you need to pay attention to as you cook.
WHAT IS DANGEROUS?
First, let’s talk about what’s dangerous. A few types of bacteria in particular are responsible for most foodborne illness: Salmonella, Escherichia coli, and Campylobacter jejuni. (If you’re wondering about the safety of cooking in plastic, see this page.) Salmonella, a resilient group of bacteria that is most commonly found in poultry and eggs, is ingested by chickens, and then contaminates their muscle tissue, intestines, and ovaries. Salmonella can migrate into the muscle of chickens, meaning that they are contaminated not just on the surface but also inside the meat. Escherichia coli is a general group of bacteria that reside in the intestines of many animals, including humans. But if ingested, some strains of E. coli can wreak havoc. Campylobacter jejuni is a spiral-shaped bacteria that causes one of the most common diarrheal illnesses in humans in America.
Food pathogens won’t let you know that they are there. Unlike the microorganisms that let you know when the food in your fridge has spoiled, these pathogens can’t be seen, smelled, or tasted. But they can be controlled—with acid, with salt, and even with some spices. But, most important, they can be controlled with temperature.
To “pasteurize” is to heat food to a temperature for a certain amount of time in order to reduce enough of the pathogens to deem it safe. We often pasteurize in sous vide cooking.
In the fridge, bacterial action and reproduction slow way down; we can keep food in there for days or weeks without worrying about pathogens growing. And at the temperatures reached when we boil or bake food, the bacteria are killed. It’s between those low and high temperatures that bacteria are happiest, so that’s where extra care is called for.
When food sits between 40°F/4°C and 140°F/60°C, it is often said to be in the “danger zone” for bacterial growth. It’s between these temperatures that potentially harmful bacteria can thrive. But what is not often referenced is that danger—and, thus, safety—isn’t just about temperature. It’s also about time. “Most people, when they talk about food safety, they oversimplify,” explains Baldwin.
For example, the FDA recommends cooking chicken breast meat (which is comprised of 5 percent fat) to 165°F/74°C in order to pasteurize it. When the center of the meat reaches that temperature, virtually 100 percent of Salmonella is killed immediately. When brought to 160°F/71°C, it takes 14 seconds to kill the Salmonella. At 155°F/68°C, it takes 50 seconds. At 150°F/65.5°C, our favorite temperature for chicken, it takes 3 minutes. We don’t recommend cooking chicken at 136°F/58°C—it’s a little more like chicken sashimi, really—but you can. It will just take 69 minutes at that temperature to be safe.
With enough time, most food pathogens are killed at 130°F/54.5°C, according to the FDA and Baldwin. For the recipes in this book, this is our magic number. We cook almost everything either at or above that temperature. (When cooking in a water bath set to 130°F/54.5°C, the food will eventually become that temperature as well.) As an extra precaution, if we plan to cook meat below our magic temperature, the first thing we do is sear it in a hot pan in order to kill off any bacteria on the surface before we circulate (see Butter-Basted Rib-Eye Steak, and Peppercorn-Crusted Roast Beef). Of course, nothing is perfect, so if you are immunocompromised or prefer to exercise greater caution for other reasons, please proceed with care. It’s important to note that the risk of eating steak prepared to medium-rare in our sous vide recipes is not any different from the risk of eating steak that is grilled to medium-rare. “For the most part, if your steak is seared, then the bacterial load is safe,” says Baldwin. “That’s why the food code allows you to have seared medium-rare steak.”
Safety for ground meat is different than for whole cuts of meat. While the inside of whole cuts of beef are sterile, harmful bacteria can be present throughout ground meat. (Of course Salmonella in poultry can be present throughout, whether the meat is ground or whole.)
Also important: Even when food is pasteurized, it isn’t safe indefinitely. The food either needs to be eaten immediately, or rapidly chilled and then refrigerated. What does “rapidly chilled” mean? It involves an ice bath (see Introduction). And once the food is in the refrigerator? Don’t leave it there too long. As Dave Arnold, author of Liquid Intelligence and an early sous vide adopter, warns, “If you store it improperly, you can get some microaerobic situations, like listeria can grow on cheese and meat slowly at refrigeration.”
And one final note: We’ve chosen not to circulate any raw garlic in this book. This is because garlic is particularly susceptible to Clostridium botulinum (or botulism), especially in a warm, anaerobic environment (like sous vide). If we don’t cook raw garlic before circulating it, we use granulated garlic powder, or we leave garlic out entirely.
Eggs
As you’ve seen throughout this chapter, egg cookery is a precise and delicate task. In this chart, we show you the importance of temperature for eggs—just one degree can make a world of change when cooking eggs sous vide, especially when held there for 60 minutes, which is the formula for many classic sous-vide egg recipes.
But, of course, these egg recipes are not dependent on temperature alone. Time is equally important. Our perfect hard-cooked egg is created in a water bath set to 194°F/90°C—no higher, no lower. But an egg cooked at 194°F/90°C for any less than 20 minutes would be too runny and raw. An egg cooked at that temperature for longer than 20 minutes would quickly become chalky and dry. We spent a lot of time testing the perfect temperature and time for our soft-poached egg, and we found that 12 minutes at the (relatively) high temperature of 167°F/75°C set the white just enough to be firm yet tender right out of the shell, while the yolk remained runny.
Follow our recipes for guaranteed perfection, but don’t hesitate to do some experimenting of your own, using this chart as a basic guide. It’s time to get cracking!
