Cooking For Geeks Part 14

Try tasting "anti-sugar" in caramel sauce (see Caramel Sauce Caramel Sauce in in Chapter4 Chapter4). Add a small quant.i.ty of Domino Super Envision to one bowl of caramel sauce, leaving a second bowl of caramel unmodified for comparison's sake. The taste of the burnt compounds in the caramel sauce will be stronger in the adulterated bowl, because the sweet sensations won't be masking them.

With lactisole, what was once perishable can be ma.s.s manufactured without the same worries about spoilage by increasing the amount of sugar and then canceling out the additional perceived sweetness. Some jams and jellies, for example, need a certain level of sugar to remain shelf-stable. Super Envision also shows up in products such as salad dressings, in which sweetness from stabilizers or thickeners would be undesirable, and in some ma.s.s-manufactured breads. Pizza dough, when baked, is more visually appealing if it turns golden brown. Adding sugar is an easy way to get a browning reaction, but sweet pizza dough isn't so appealing.

For a list of industrial-style recipes-cereal coatings, instant chocolate milk mix, marshmallows, meringue toppings-see Domino's Envision Applications page at http://www.dominospecialtyingredients.com/recipes/envision_more.html.

Savory French MeringuesWithout sugar, meringues-well, egg whites-bake into a dry brittle foam that resembles Cheetos (but without the flavor): it's extremely crunchy and, without any flavorings, not particularly pleasant. When sugar is added, the meringue turns into something light, slightly chewy, and delightful.Try the following experiment to understand how sugar helps stabilize meringues and how lactisole masks the sweetness.Start by separating six egg whites into a bowl and whipping to stiff peaks. Using a scale, weigh out into three small gla.s.s or metal bowls:Standard meringues - 50g whisked egg white - 20g granulated sugar Meringues sans sugar - 50g whisked egg white Meringues with "anti-sugar"

- 50g whisked egg white - 20g granulated sugar - 1g Domino Super Envision Transfer each batch into a piping bag. (A plastic bag with a small cut in the corner works well.) Pipe onto a Silpat or a cookie sheet lined with parchment paper.NoteAdd in chopped nuts, dried fruit, and/or chocolate chips to extend it. Try dipping the baked meringue in tempered chocolate as well.Bake the meringues in an oven set to 200F / 95C for several hours, until dry. (Trying this in the evening? You can set your oven to ~300F / 150C, pop the cookies in, and then turn the oven off and come back the next morning.)NoteDon't try baking meringues directly on the cookie sheet. Proteins are very sticky and will bind to it, making it hard to remove them without breaking them. Because it's flexible, the Silpat or parchment paper can easily be peeled off the back of the cooked meringues.You can see the difference instantly in the "meringue" made without sugar: the egg white doesn't flow as smoothly out of the piping bag. The standard and anti-sugar meringues have the same texture, but the taste of the standard one is, as expected, sweet. The anti-sugar one tastes pretty much like nothing, as egg white doesn't carry a strong flavor of its own.[image]Meringues sans sugar.[image]Standard meringues.[image]Anti-sugar meringues.

Meat Glue: Transglutaminase One of the more unexpected food additives is transglutaminase transglutaminase, a protein that has the ability to bond glutamine with compounds such as lysine, both of which are present in animal tissue. In plain English, transglutaminase is "glue" for proteins.

Transglutaminase isn't used to change the texture of foods or to modify sensations of flavor. Rather, the food industry uses it re-form sc.r.a.p meats into large pieces (McNuggets!). You didn't actually think that gorgeous hunk of ham at the deli counter was one piece of meat, did you? From the rare boneless pig?

Transglutaminase is also used to thicken milk and yogurts by making their proteins longer in the same way that adding longer polysaccharides in gelling applications makes things thicker. Additionally, it is used to firm up pastas, to make breads more elastic (able to stretch without tearing), and to improve gluten-free breads for those with celiac disease.

For food hackers, though, the compelling opportunities for transglutaminase reside primarily in meat-binding applications. Food hackers have, of course, seized the opportunity to use it to make Frankenstein meats (all in the name of fun). You can "glue" white fish to red fish, make a t.u.r.ducken (a turkey-duck-chicken dish) that holds together, and make a heatstable aspic, relying on transglutaminase instead of heat-sensitive gelatins or aspics.

The recipes that follow will give you some starting ideas, but really the concept of "meat welding" can apply to any meats that you want to stay together, including fish and poultry. You can glue scallops together in a long chain, wrap chicken around fillings (binding the chicken to the other end of itself), and wrap bacon around scallops.

The reaction occurs at room temperature and takes around two hours to set, so plan ahead. Use about 1% transglutaminase for the total weight of your food. You can sprinkle it dry on the food item or create a slurry (2 parts water to 1 part transglutaminase) and brush it onto the surfaces to be glued. Once adhered together, let the join rest for at least two hours; otherwise, you will shear and break the bonds as they're setting.

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Chicken and steak bonded together with transglutaminase. Mmm, Doublemeat Palace!

Keep in mind that, because you're you're made of protein, you should take care to not get it on your skin or inhale the powder. Unlike real glue, transglutaminase is actually a chemical catalyst that literally bonds the two sides together at a molecular level. Gloves and a respirator mask are good insurance. Since transglutaminase is a protein itself and has the same structures as the amino acids it binds, it's also capable of binding to itself. After a few hours at room temperature, though, it loses its enzymatic properties, so it's not a huge deal if you spill a bit on your work surface. Once opened, store it in your freezer to slow the rate of the binding reaction. made of protein, you should take care to not get it on your skin or inhale the powder. Unlike real glue, transglutaminase is actually a chemical catalyst that literally bonds the two sides together at a molecular level. Gloves and a respirator mask are good insurance. Since transglutaminase is a protein itself and has the same structures as the amino acids it binds, it's also capable of binding to itself. After a few hours at room temperature, though, it loses its enzymatic properties, so it's not a huge deal if you spill a bit on your work surface. Once opened, store it in your freezer to slow the rate of the binding reaction.

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- Instructions for use.Create a slurry of water and transglutaminase and brush it onto the surfaces that you want to join. Press them together and wrap with plastic wrap. Store in fridge for two hours or longer.

NoteTry vacuum-packing the food. This will improve the fit between the two pieces of meat.

- Uses.Protein binder. Used by the food industry to take sc.r.a.ps of meats and form them into a larger shape, such as deli-style sliced turkey, and to thicken dairy products such as yogurt.

- Origin.Manufactured using the bacteria Streptomyces mobaraensis Streptomyces mobaraensis. The main producer of transglutaminase is a j.a.panese company, Ajinomoto, which sells it under the name Activa. (This is the same company that originally formed to manufacture and sell MSG.) - Chemistry.Transglutaminase is an enzyme that binds the amino acid glutamine with a variety of primary amines. Any place where glutamine and a suitable amine are present, transglutaminase can be used to crosslink the two. Transglutaminase is itself digestible (it's a protein) and the enzymatic reaction ceases after a few hours, so there's no danger of it "gluing" your insides together (once it has set, that is, which would happen during cooking anyway). Transglutaminase acts as a catalyst on glutamine and lysine, causing the atoms composing the two groups to line up so that they form covalent bonds.

NoteA covalent bond is one in which two atoms share an electron, resulting in a lower energy state. Electrons are "lazy" in the sense that they prefer states that take less energy to maintain.

To visualize the reaction, imagine spreading apart the fingers of your left and right hands and touching the tips together, left thumb to right thumb, left pinky to right pinky, etc. Without some amount of coordination, getting the atomic "fingers" to line up just doesn't happen. Transglutaminase helps by providing the necessary atomic-level guidance for the two groups to touch. And once they touch, they can form covalent bonds and stick. Continuing the finger a.n.a.logy, it's a bit like having superglue on your fingers: once they are lined up and are touched together, they stay together.

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Before interaction, strands of proteins with glutamine and lysine groups are unattached (left); after interaction, the glutamine and lysine groups are covalently bonded wherever transglutaminase has a chance to catalyze. Note that transglutaminase itself does not remain as part of the bond after the reaction.

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While you can pull apart items joined with transglutaminase, the individual meats themselves may be weaker than the join.

Technical notes Concentration ~0.5% to 1% of meat weight.

Notes Cold-set for at least two hours-that is, apply to meat and let rest in fridge for two hours. Reaction time is correlated with temperature, so it takes longer to set at colder temperatures.

Temperature Heat-stable once set.

Bacon-Wrapped ScallopsIt's cool to see bacon-wrapped scallops where the bacon just sticks to the scallop. It's also a good example of how to work with transglutaminase.In a small bowl, mix roughly 2 parts water to 1 part transglutaminase to create a slurry.On a small plate that will fit in your fridge, lay out: - 8 scallops as large and as cylindrical as possible, patted dry - 8 slices bacon, cut in half so that they can wrap around a scallop one time Using a brush, coat one side of each piece of bacon with the slurry. Place a scallop on the bacon and roll the bacon around the scallop. Repeat for each scallop and transfer to the fridge for at least two hours to allow the transglutaminase to set.After resting, the bacon should be well adhered to the scallops.Preheat your oven to 400F / 200C.Place the scallops in a hot frying pan lightly coated with oil or a small amount of b.u.t.ter, with one of the "exposed" ends down. This will cause a Maillard reaction and develop a nice layer of flavor on the scallops. After a minute or so, flip the scallops over so that the other exposed side is in contact with the pan and immediately transfer your frying pan to the oven.Finish in the oven for about five to eight minutes, until the bacon is done and the scallops are cooked.Note - Use only an oven-safe frying pan in your oven. Some commercial frying pans have silicone handles-typically blue-that are oven-safe.[image]Use a brush to coat one side of a strip of bacon with transglutaminase. (If you don't already have a pastry brush, consider getting one made with plastic bristles, because that type will not leave strands behind.)[image]Carefully roll the bacon around the scallop. The transglutaminase will not bond instantly, so you will need to pinch and press the items together. Let set for two hours in the fridge.[image]Pan sear the scallops on high heat, flip to sear on both sides, and transfer to the oven to finish.[image]A cross-sectional slice of the finished product shows the joined surface of the bacon and the scallop. (Shown on top of a leaf of bok choy.) Shrimp Roll-upSince transglutaminase binds proteins at the molecular level, you can also use it as a binder to form ground meats into a solid form (Spam!). Imagine taking wood glue and, instead of gluing two boards together, using the glue to re-form a piece of wood from sawdust. Yes, just like particleboard or chipboard. The next recipe demonstrates this concept.Puree with an immersion blender or food processor: - 175g shrimp, raw, peeled, and deveined - 50g water - 10g transglutaminase Transfer the puree to the center of a large sheet of parchment paper. Using a spatula, fan out the puree so that it's flat enough to place a second piece of parchment paper on top of it. Using a rolling pin, roll the puree out to a thickness of 1/8 / 0.3 cm, just as you would for a pie crust dough. Transfer the "sandwiched" puree to the fridge and let rest for a minimum two hours, preferably overnight.In a large pot, bring salted water to a rolling boil.Fill a large bowl with ice water.Using a sharp chef's knife, cut a portion of the sandwiched puree down to a size that will fit in your pot. Carefully slip the sheet into the boiling water. The parchment paper should detach from the shrimp puree; this is expected. After 30 seconds to a minute, use a spider (or slotted spoon and tongs, if you're careful) to fish out the shrimp sheet from the boiling water, and transfer it to the ice water bath to stop the cooking process.You should now have a "sheet" of shrimp that you can slice into noodles or use as a wrap around food items. To make shrimp noodles, slice the shrimp sheet into thin slices, which can then be floated in seafood broth or tossed with seared tofu, sesame seeds, sauteed green onions, and soy sauce. Or, try making "reverse sushi," using the shrimp sheet as the wrapper for the rice in place of the customary nori seaweed wrapper.[image]You can use rubber bands on the edges of your rolling pin to achieve a consistent thickness. This photo shows the shrimp and transglutaminase puree sandwiched in parchment paper.[image]A spider is a handy tool for fetching delicate items from boiling water. Note that the shrimp noodles and parchment paper have separated in the boiling water.

Liquid Smoke: Distilled Smoke Vapor Smoking-burning wood chips and directing either the hot or cold smoke vapors to come in contact with items such as meats-is a method for curing and preserving foods. Smoking also deposits a number of flavors onto the food that are generated as byproducts of the chemical reactions that occur when wood is combusted. The commercial food industry uses liquid smoke to infuse smoke flavor into foods that are traditionally smoked, such as bacon, and into foods for which the flavor is enhanced by smoke essence, such as "smoked" tofu.

The simplest way of creating a smoked flavor in your cooking-besides actually smoking it-is to include ingredients that are already smoked and contain those chemical compounds. You can infuse smoke flavors into your dish by adding spices such as chipotle peppers or smoked paprika, or by using dry rubs with smoked teas such as Lapsang Souchong. Tobacco, too, can be used to similar effect; some novel restaurant dishes include components like tobacco-infused creme anglaise. However, including smoked ingredients will also bring along the other flavors of the substance being used. Some dishes can use smoked salts, for example, but for many applications, this will contribute too much salt. This is where liquid smoke comes in.

A cook can use liquid smoke to highlight the smoky "toasted" flavors of foods, especially those that have similar molecular compounds to smoke, such as coffee, peanut b.u.t.ter, or Scotch whisky. You can also use it to impart smoke flavor in those situations where grilling isn't an option-say, on the 27th floor of your apartment complex.

NoteWhen buying liquid smoke, look for an ingredient list that reads "smoke, water." Try to avoid products that have mola.s.ses or other additives.

Some of the more unusual uses allow for bringing smoked flavor to foods that can't normally be tossed onto a wood-burning grill, such as tofu, ice cream, or liquids (along with some sandalwood incense and Chanel N5, if you're Maggie from Northern Exposure) Northern Exposure). b.u.t.ter also has some of the same phenols as smoke; try adding it to b.u.t.ter for table service with bread.

The big long evil list of nasty chemicals and ingredients that one would expect to see on a liquid smoke bottle? "Water, smoke." In and of itself, liquid smoke is not artificial. It does not undergo any chemical modifications or refining steps that alter or change the compounds that would have been present in traditional smoking.

In theory, some of the mutagenic compounds (those that cause cancer) normally present in traditionally smoked foods are present in much smaller quant.i.ties in liquid smoke, meaning that liquid smoke might actually be somewhat safer for you than traditionally smoked foods. However, be aware that liquid smoke will have some amount of mutagenic compounds present. As a subst.i.tute for smoking foods, it should be as safe as traditional smoking, but you probably shouldn't douse a teaspoon of it on your morning eggs every day until further research is done.

In addition to the following two recipes, consider revisiting the Salmon Gravlax recipe from earlier in this chapter (see Salmon Gravlax Salmon Gravlax) and adding liquid smoke to give it a cold-smoked flavor.

S'mores Ice CreamThis recipe uses liquid smoke to impart the toasted flavor of campfire-roasted marshmallows. The concept was inspired by a demo by Kent Kirshenbaum of NYU's Experimental Cuisine Collective.You'll need a standard ice cream mixer, or you can go all-out geek and either make your own (see DIY Lego Ice Cream Maker DIY Lego Ice Cream Maker in in Chapter3 Chapter3) or use liquid nitrogen or dry ice. For the latter options, see the instructions in Making ice cream Making ice cream in in Chapter7 Chapter7.To create the base, combine in a mixing bowl: - 2 cups (475g) whole milk - 1 cup (238g) heavy cream - cup (75g) sugar - cup (75g) chocolate syrup - cup (25g) medium-sized marshmallows - 15 drops (0.75g) liquid smoke Proceed with the directions for your chosen method of making ice cream. Once the ice cream has set, stir in: - 1 cup (60g) graham crackers, toasted and chopped into pieces Serve with hot fudge or chocolate syrup-whipped cream, cherries, and nuts optional.[image]Oven-Cooked Barbeque RibsIn a large baking pan (9 13 / 23 cm 33 cm), place: - 2 pounds (1kg) pork baby back ribs, excess fat trimmed off In a small bowl, create a dry rub by mixing: - 1 tablespoon (15g) salt - 1 tablespoon (15g) brown sugar - 1 tablespoon (9g) c.u.min seed - 1 tablespoon (9g) mustard seed - 20 drops (1g) liquid smoke Cover ribs with spice mix. Cover baking pan with foil and bake at 300F / 150C for two hours.In a small bowl, create a sauce by mixing: - 4 tablespoons (60g) ketchup - 1 tablespoon (15g) soy sauce - 1 tablespoon (15g) brown sugar - 1 teaspoon (5g) Worcestershire sauce Remove foil from baking pan and coat ribs with sauce. Bake for 45 minutes, or until done.Note - Experiment with other savory spices in the dry rub, such as chilies, garlic, or paprika. Also, try adding items such as onions, garlic, or Tabasco to the sauce.

Making Liquid SmokeThe smells that we a.s.sociate with that smoky, barbeque goodness result solely from the chemical reactions that occur during pyrolyzation (burning) of wood. The flavor that you think of as "smoky" does not come from a chemical interaction between the food and the smoke. This lucky quirk means that the chemicals in smoke can be isolated, so the stage of generating smoke flavor can be separated from the step of applying that flavor to food.You can make your own liquid smoke for about $20 worth of supplies and a few hours of your time. For day-to-day uses, you're way better off buying liquid smoke from the grocery store, but it's rewarding to see how straightforward it is to make, and the process touches on some elementary chemistry techniques as well.Liquid smoke is made by heating wood chips to a temperature high enough for the lignins in wood to burn, condensing the resulting smoke, and then dissolving it in water. The water-soluble components of smoke remain dissolved in the water, while the non-water-soluble components either precipitate out or form an oil layer that is then discarded. The resulting product is an amber-tinted liquid that you can brush onto meats or mix in with your ingredients.What actually happens when you burn wood? Wood is primarily made of cellulose, hemicellulose, and lignin, which during burning convert to several hundred different chemical compounds. The aromatic molecules that provide smoke flavoring are generated by the lignin, which breaks down at around 752F / 400C. Cellulose and hemicellulose break down at lower temperatures (480570F / 250300C), but they generate compounds that both detract from the flavor and are mutagenic. This is why, when grilling, you should make sure you have a hot fire, which will guarantee that the lignins, and not just the celluloses, break down.Making your own liquid smoke can be a little tricky because of the high heat required to properly burn the lignins and the difficulty in correctly capturing the resulting lignin-based compounds, not to mention the need for proper chemistry lab equipment for creating a closed system and heating it safely.[image]Kent Kirshenbaum demonstrates making liquid smoke during a talk at NYU's Experimental Cuisine Collective (see http://www.experimentalcuisine.org). Here, he burns hickory chips using a propane blowtorch. The smoke is then piped through a water flask (on right), which traps the water-soluble particulate in suspension.Start by placing wood chips-either hickory or cedar-into a vessel that can be sealed (to create a closed system) and heated with a burner or blow torch. Run a line from the closed system into a container of water, so as to filter the smoke vapor through the water. Heat the vessel, making sure to get it hot enough for the lignins to burn. Because the "tasty molecules" of the smoke are water soluble, the water will end up capturing those flavors, becoming your liquid smoke. Discard any solids that precipitate out or oils that separate and float to the top. Theoretically, something like this could be done with a pipe on a charcoal grill, with the pipe sealed on one end and copper tubing running from the other end into a water container, but it's definitely not up to lab safety protocols.If you do manage to make your own liquid smoke-it does make for a fun experiment-you'll probably find that it's a lot more work than it's worth. Still, understanding that liquid smoke is nothing more than smoke particles captured in water removes most of the mystery about what's in the bottle at your grocery store.

Chapter7.Fun with Hardware.

IF YOU'RE ANYTHING LIKE ME, THIS IS THE FIRST CHAPTER YOU'LL FLIP TO WHILE PERUSING THIS BOOK IN THE BOOKSTORE. And, might I add, you have And, might I add, you have excellent excellent taste. taste.

While this chapter is designed such that a foodie-geek can jump right in, really, it does a.s.sume that you're up to speed with pairing flavors, that you understand various cooking and baking techniques, and that you're familiar with some of the chemistry concepts covered in earlier chapters. So, don't judge this book solely by this chapter.

Modern commercial kitchens, probably including the high-end ones in your town, use many tools that consumers rarely encounter but that can help create some absolutely stellar meals. We'll cover a few of the commercial and industrial tools used in preparing foods, and throw in a few, uh, "crazy" (and fun!) things that you can do as well.

Time and temperature really are the two key variables in cooking (see Chapter4 Chapter4). Under normal circ.u.mstances, cooking is performed with these variables at moderate values: roasting potatoes for half an hour at around 350F / 177C, baking pizza at 450F / 230C for 10 minutes, or churning ice cream at 20F / 29C for an hour or so. But what happens when you move one of these variables to an extreme?

Cooking at extreme temperatures isn't as uncommon as it might sound at first. Potatoes, for example, wrapped in foil and roasted in the coals of a campfire are in an environment that reaches well above 800F / 425C. With this in mind, it shouldn't be too much of a stretch to imagine baking thin-crust pizza in 45 seconds at 900F / 480C (the result is amazingly good!). And making ice cream in 30 seconds with liquid nitrogen isn't just fun; this technique actually makes great great ice cream because the water crystals don't have time to form large aggregates, resulting in a smoother texture. ice cream because the water crystals don't have time to form large aggregates, resulting in a smoother texture.

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It's also possible to move cooking times to extreme values. Sous vide Sous vide cooking, the topic of the first half of this chapter, enables this by precisely controlling the temperature of the cooking environment, a water bath, so that it is equal to the target temperature of the cooked food. This allows time to run to extreme values without any risk of overcooking (at least in the conventional sense). cooking, the topic of the first half of this chapter, enables this by precisely controlling the temperature of the cooking environment, a water bath, so that it is equal to the target temperature of the cooked food. This allows time to run to extreme values without any risk of overcooking (at least in the conventional sense).

Beyond sous vide, other techniques can be used to produce new culinary creations-or at least, to return an iota of sanity to the life of the commercial chef by making some preparations vastly easier than they are with traditional methods. Filtration makes easy work of creating stocks, clear juices, and consommes. Cream whippers can "whip" air into liquids, allowing for the quick creation of not just whipped creams, but also mousses, foams, and even cakes. And for extreme temperature variations, we'll take a look at blowtorches and high-heat ovens on the hot side and liquid nitrogen and dry ice on the cold side. We'll talk about all of this in the second half of this chapter.

Unfortunately, many of these techniques involve tools that you're unlikely to find at your nearest shopping mall. Expect to do some online sleuthing or to break out the wire cutters and soldering iron, and be willing to try, try, and try again. This chapter is all about experimentation. As with the modern food additives section in Chapter6 Chapter6, the "recipes" here are really only simple examples to give you a sense of where to start with your experiments. Use your creativity and imagination to create your own dishes!

Brownies in an OrangeUsing food as a serving bowl is nothing new: stew in a bread bowl, sliced fruit in half a cantaloupe, and now, brownies in an orange.[image]Cut the top off and trim out the center.[image]Fill with brownie mix (guilty pleasure).[image]Bake until a toothpick inserted 1 / 2.5 cm deep comes out clean. Dust with powdered sugar.

Sous Vide Cooking With a name like "sous vide," this cooking technique sounds foreign, and for good reason: the French chef George Pralus introduced it to the culinary world in the 1970s. While foreign in origin, it is certainly not complicated or mysterious. At its simplest, sous vide cooking is about immersing a food item into a precisely temperature-controlled water bath, where the temperature is the same as the target temperature of the food being cooked. Translation? Ultra-low-temperature poaching. And since the temperature of the water bath isn't hotter than the final target temperature, the food can't overcook. Sous vide cooking essentially locks the variable of temperature in the "time * temperature" formula.

The temperature of the water bath is chosen to trigger chemical reactions (e.g., denaturing, hydrolysis) in some compounds in the food while leaving other compounds in their native state. It is one of the biggest culinary revolutions to hit the commercial cooking scene in the past few decades, but has appeared in the U.S. only recently. If I could pick only one new cooking method out of this entire book for you to try, sous vide would be it, hands down. The reason sous vide is so, well, amazing is that foods cooked this way have no gradient of doneness and the a.s.sociated overcooked outer portion. Instead, the entire piece of food has a uniform temperature and uniform doneness.

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Foods cooked sous vide have no temperature gradient, meaning that the entire portion of food is cooked to a consistent level of doneness.

The name sous vide (meaning "under vacuum") refers to the step in the cooking process where foods are placed in a vacuum-pack plastic bag and sealed. Using a vacuum bag-a plastic bag that is sealed after all the air in it has been removed-allows the water in the bath to transfer heat into the food while preventing the water from coming into direct contact with it. This means the water does not chemically interact with the food: the flavors of the food remain stronger, because the water is unable to dissolve and carry away any compounds in the food. (Sous vide is a funny name; I think it should have been called "water bath cooking," because the actual heat source is usually a bath of water. Bain-marie was already taken, I suppose. Still, as with the name "molecular gastronomy," once something gets popularized, it tends to stick.) [image]

The steak tip on the left was cooked sous vide at 140F / 60C; the one on the right was pan-seared. Note that the sous vide steak has no "bull's eye" shape-that is, it's consistently medium-rare, center to edge, while the seared steak is well-done on the outside and rare in the middle.

Sous vide cooking doesn't have to be done with a sealed bag in water. A few items don't need to be packed at all. Eggs, for example, are already sealed (ignoring the microscopic pores), and when using this technique for secondary applications like preheating vegetables such as bok choy for steaming, there's no benefit to sealing the food in plastic.

You can also use other fluids instead of water: oil, for example, or even melted b.u.t.ter. And because meats don't absorb fat the same way that they can water, when using one of these as the liquid medium some applications can skip sealing. This can be extremely useful for those foods that might be difficult to seal. Chef Thomas Keller, for example, has a recipe for poaching lobster tails in a bath of b.u.t.ter and water (beurre monte, melted b.u.t.ter with water whisked in, which has a higher burning temperature than b.u.t.ter alone).

Temperature-controlled air would technically work as well, but the rate of heat transfer is much, much slower than for water-roughly 23 times slower. Given the low temperatures involved, something like chicken in a 140F / 60C "air bath" would take so long to come up to temperature that bacterial growth would be a serious concern. Using a liquid such as water ensures that heat can penetrate the food via conduction-liquid touching plastic touching food-rather quickly. Water is cheap and easy to use, so you'll almost always see it called for, but some chefs do occasionally use other liquids.

The cla.s.sic example given to explain how sous vide cooking works is cooking an egg. Since different egg proteins denature and coagulate at slightly different temperatures (most are in the range of 144158F / 6270C), holding an egg at various temperatures within that range will result in varying consistency of egg white and yolk. (Refer back to the discussion of egg proteins setting at different temperatures in 144F / 62C: Eggs Begin to Set 144F / 62C: Eggs Begin to Set in in Chapter4 Chapter4.) [image]

To some, a "perfect" soft-cooked egg should have a slightly runny, custard-like yolk and a mostly set white. Cooking an egg in water brought to a boil can result in an overcooked end result, because the temperature of the egg ramps up to boiling point until it is pulled out. In sous vide, the temperature of the egg reaches only the ideal temperature of the cooked egg, so it cannot overcook.

By immersing the egg in a water bath held at that temperature you ensure that the egg cannot get any hotter, so in theory, those proteins that set at a higher temperature will remain in their native form. In reality, most chemical reactions in cooking aren't specific to a particular temperature, but are dependent on time-at-temperature. In practice, though, this simple model is accurate enough to explain how sous vide cooking works.

For a "perfect" soft-cooked egg, try cooking it sous vide at 146F / 63C for one hour. Because eggs contain many proteins that set at slightly different temperatures, you can experiment by adjusting the temperature up or down a few degrees to suit your personal preferences.

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Cooking eggs in a sous vide bath at 144.5F / 62.5C.

For other foods, consider the compounds they contain, determine the temperatures at which the compounds undergo their different transformations, and pick a temperature high enough to trigger the reactions you do want, yet low enough not to trigger the ones you don't.

NoteTip: after cooking an egg sous vide, crack open and drop the egg (without sh.e.l.l!) into a pot of just-boiled water. Then fetch the egg out immediately. The hot water will rapid-set the outside of the egg for better appearance and easier handling.

Sous vide cooking isn't a magic bullet, though. For one thing, the textures of some foods break down when held at temperature for any extended period of time. Some types of fish will break down due to enzymatic reactions that normally occur at such a slow rate that they are not noticeable in traditional cooking methods. Sous vide also doesn't reach the temperatures at which Maillard reactions or caramelization occur; meats cooked sous vide are commonly pan seared or even blowtorched briefly after cooking to introduce the flavors brought about by these browning reactions. The largest drawback, however, is the requirement to pay serious attention to food safety issues and pasteurization.

NotePasteurization reduces bacterial levels to a point where food can be considered reasonably safe. If it is stored improperly after pasteurization, bacteria can reproduce above safe levels. reduces bacterial levels to a point where food can be considered reasonably safe. If it is stored improperly after pasteurization, bacteria can reproduce above safe levels.Sterilization completely eliminates the target bacteria. completely eliminates the target bacteria.

Foodborne Illness and Sous Vide Cooking Sous vide cooking, when done properly, can safely create amazingly tender chicken, a perfect soft-cooked egg, or a succulent steak. However, it's also possible to set up a perfect breeding ground for bacteria if the food is mishandled. The heat involved in sous vide cooking is very low, so if you start with, say, a very large piece of frozen meat, it will take a long time to come up to temperature and will spend too much time in the breeding ranges of common foodborne pathogens.

With sous vide cooking, it is possible to cook meats to a point where they are texturally done-proteins denatured-but have not had sufficient time at heat for bacteria and parasites to be rendered nonviable. For these reasons, sous vide cooking has run afoul of some restaurant health inspectors: without proper procedures and clear guidelines, pathogens such as listeria and botulism are valid concerns when the food is mishandled. These concerns can be addressed with a clear understanding of where the risks are and what factors mitigate them. With the popularity of sous vide cooking on the rise, health inspectors are creating new guidelines, and depending upon where you live, they might already be comfortable blessing restaurants that have demonstrated proper handling procedures.

With low-temperature cooking, it's possible to violate the "40140F / 460C danger zone" rule (see Foodborne Illness and Staying Safe Foodborne Illness and Staying Safe in in Chapter4 Chapter4) and its derivative rule: - Thou shalt pasteurize all potentially contaminated foods.

In the FDA's Bad Bug Book Bad Bug Book, the highest survival temperature listed for a foodborne pathogen at the time of this writing is 131F / 55C, for Bacillus cereus Bacillus cereus, which is relatively uncommon (you're 50 times more likely to get ill from salmonella) and, while unpleasant, has caused no known fatalities. The next highest survival temperature listed by the FDA is 122F / 50C, which gives you an idea of how much of an outlier B. cereus B. cereus is. is.

Why is the danger zone a problem for dishes cooked sous vide, even at temperatures high enough to kill bacteria? The issue is that food cooked sous vide takes longer to come up to temperature than food cooked via other methods, and during that time heat-stable toxins can form. A number of foodborne illnesses are brought about by toxins and spores produced by bacteria. Even if the bacteria are killed, there could be sufficient time for them to produce enough toxins to be harmful in overly large cuts of meat. To be safe, make sure that the core temperature of your food product reaches temperature within two hours. To be safe, make sure that the core temperature of your food product reaches temperature within two hours.

The temperatures in the danger zone rule build in a safety cushion, and for a broad, simple rule for all consumers, this is a good thing. If you are going to violate the temperature rules-e.g., cooking fish to only a rare temperature-be aware that you risk contracting a foodborne illness. For sous vide dishes that go from fridge to plate in less than two hours and and where the danger zone rule is violated, the risks are equivalent to eating the raw item. If you are comfortable eating beef tartar or raw tuna in sushi, foods cooked sous vide are no worse when properly handled. Still, if you are cooking for someone who is in an "at-risk" group, you should avoid serving these foods just as you would avoid serving raw or undercooked items, especially as you can prepare a number of dishes sous vide that pasteurize the food and taste fantastic. where the danger zone rule is violated, the risks are equivalent to eating the raw item. If you are comfortable eating beef tartar or raw tuna in sushi, foods cooked sous vide are no worse when properly handled. Still, if you are cooking for someone who is in an "at-risk" group, you should avoid serving these foods just as you would avoid serving raw or undercooked items, especially as you can prepare a number of dishes sous vide that pasteurize the food and taste fantastic.

Sous vide cooking methods can be grouped into two general categories: cook-hold and cook-chill. In cook-hold, cook-hold, the food is heated up and held at that temperature until it is served. In the food is heated up and held at that temperature until it is served. In cook-chill cook-chill, the food is heated up, cooked, then rapidly rapidly chilled in the fridge or freezer for later use. (Use an ice-water bath to shock the food.) With the cook-chill approach, a greater amount of c.u.mulative time is spent in the danger zone: first while the food is being heated, then while it's being chilled, and then while it's being heated again. Since it's the c.u.mulative time in the danger zone that is of concern, I find it easier to use the cook-hold method, so that I simply don't have to worry about the c.u.mulative time. chilled in the fridge or freezer for later use. (Use an ice-water bath to shock the food.) With the cook-chill approach, a greater amount of c.u.mulative time is spent in the danger zone: first while the food is being heated, then while it's being chilled, and then while it's being heated again. Since it's the c.u.mulative time in the danger zone that is of concern, I find it easier to use the cook-hold method, so that I simply don't have to worry about the c.u.mulative time.

For the home chef concerned about food safety (that is is all of you, right?), there is an easy way to remain safe (well, all of you, right?), there is an easy way to remain safe (well, safer safer; it's all about risk mitigation and relative risks). When cooking sous vide, give preference to the cook-hold method, and be aware of the minimum temperatures required for pasteurization. This is an oversimplification, but it's an easy rule to follow. The better boundary guideline is to make sure to get the food above 136F / 58C-the lowest temperature given in the FSIS food guidelines-within a two-hour window and to hold it above that temperature for long enough to pasteurize it.

Note.

- You can hold food above 140F / 60C for as long as you want; it's actually safer than storing food in the fridge.

Pasteurization is not not an instantaneous process. For food to be pasteurized, it an instantaneous process. For food to be pasteurized, it must must be held at the target temperature for a sufficient length of time for the appropriate reduction of bacteria to occur. Consumer guidelines for cooking meats such as poultry specify temperatures of 165F / 74C because at that temperature the bacterial count will be reduced so quickly that there is no need to address the concept of hold time, and slight errors in temperature measurement and thermometer calibration will not be of concern. be held at the target temperature for a sufficient length of time for the appropriate reduction of bacteria to occur. Consumer guidelines for cooking meats such as poultry specify temperatures of 165F / 74C because at that temperature the bacterial count will be reduced so quickly that there is no need to address the concept of hold time, and slight errors in temperature measurement and thermometer calibration will not be of concern.

With meats such as chicken breast, the required hold time at 140F / 60C for enough bacteria to die can be half an hour or more, meaning the food needs to reach 140F / 60C and then sit at that temperature for at least the prescribed amount of time. We'll cover the necessary hold times for different kinds of foods later in this chapter, because the hold times vary depending upon the composition of the food.

Cooking in the...Dishwasher?Invariably, some people raise their eyebrows when I first start to describe sous vide cooking. The idea of cooking in a water bath is just plain foreign at first. But remember: cooking is about the application of heat, regardless of the source of that heat. Sous vide cooking is not the same as boiling food (that'd require the water to be around 212F / 100C). It's not even like simmering or poaching, in which the liquid environment is often hotter than the target temperature. Sous vide is the application of a very low, controlled temperature, in some cases as low as 116F / 47C.Consider a piece of salmon cooked to medium doneness, which is an internal temperature of around 126F / 52C. On the grill, you'd cook the salmon until the core temperature reached 126F / 52C, but by that point, the outer portions of the fish would be hotter. In a water bath at 126F / 52C, the entire piece of fish would reach that temperature-but no higher. A / 20 mm-thick fillet of salmon will cook to medium in about 30 minutes at 126F / 52C.NoteNote that this temperature does not not pasteurize the salmon. Handle it like raw/undercooked fish. pasteurize the salmon. Handle it like raw/undercooked fish.If you're anything like me, at some point, the following thought will occur: wait a second, my tap water is about that hot...hmm... wait a second, my tap water is about that hot...hmm... I've tried it, and it I've tried it, and it does does work: place your fish (sealed in an airtight bag) in a container in your sink, flip open the hot water tap, and keep a slow, constant trickle running. Check the temperature with a thermometer, and set your timer. It's not exactly energy efficient, even at a slow trickle, but it work: place your fish (sealed in an airtight bag) in a container in your sink, flip open the hot water tap, and keep a slow, constant trickle running. Check the temperature with a thermometer, and set your timer. It's not exactly energy efficient, even at a slow trickle, but it does does work, sorta, at least for fish. Foods like chicken and beef require water hotter than what your tap delivers, and even if you did manage to get a stream of 140F / 60C water out of your tap, long cook times (e.g., 24-hour brisket) would make it impractical. work, sorta, at least for fish. Foods like chicken and beef require water hotter than what your tap delivers, and even if you did manage to get a stream of 140F / 60C water out of your tap, long cook times (e.g., 24-hour brisket) would make it impractical.So, the next thought a geek might have would be: wait a sec, did you say 140F / 60C? That's about how hot dishwashers get! wait a sec, did you say 140F / 60C? That's about how hot dishwashers get! Search online for "dishwasher recipes" and yup, it has been done. People have cooked fish and even vegetarian lasagna in their dishwashers. If you try it, just remember to keep the time from fridge to plate at two hours or less, and treat the food as potentially raw or undercooked. Search online for "dishwasher recipes" and yup, it has been done. People have cooked fish and even vegetarian lasagna in their dishwashers. If you try it, just remember to keep the time from fridge to plate at two hours or less, and treat the food as potentially raw or undercooked.[image]

Sous Vide Hardware Sous vide cooking requires very little in the way of hardware: a heater to keep the water bath at temperature, and a vacuum sealer to package foods so that they can be placed in the water bath without coming into direct contact with the water. While the commercial tools can still set you back many hundreds of dollars, a DIY version can easily be made for less than $100, and resealable plastic bags can be used in lieu of a standard vacuum system.

Water heaters One difficulty of sous vide cooking is maintaining a water bath at a precise temperature, +/ 2F / 1C. The early days of sous vide cooking used laboratory equipment designed to hold water baths at the precise temperatures needed for controlling chemical reactions, but as you'd imagine, the lab gear has the drawback of being expensive. We're right on the cusp of a wave of new products targeted at the home chef who wants to cook sous vide, and while the prices might still be out of your reach, they'll surely come down until at some point the "three-in-one rice cooker" (steamer and slow cooker, too!) will become a four-inone rice cooker.

Industrial circulators. These are lab-grade units that either are designed to be submerged into a container of water (e.g., hotel pans) or are enclosures with built-in containers. PolyScience is the most common manufacturer ( These are lab-grade units that either are designed to be submerged into a container of water (e.g., hotel pans) or are enclosures with built-in containers. PolyScience is the most common manufacturer (http://www.cuisinetechnology.com), with new units costing around $1,000. Grant is also a common maker (http://www.grantsousvide.com). With luck, you can pick up a used unit at an online auction site for considerably less, but be aware that you'll have no idea what chemicals or pathogens a used unit might have been exposed to. If you do go this route, a three-step wash seems to be the standard cleaning regimen suggested: run it in a bath of vinegar, then one of bleach, and finally one of rubbing alcohol.

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Consumer sous vide products. With the popularity of sous vide rising, a number of consumer products have recently been released or are in development that bring the cost of the hardware down to the $400 range, such as the Sous Vide Supreme. While still on the expensive side, as a piece of consumer kitchen equipment, it's not unreasonable, and prices will inevitably fall. Given the versatility and usefulness of the cooking technique, definitely consider looking at this category of products. See With the popularity of sous vide rising, a number of consumer products have recently been released or are in development that bring the cost of the hardware down to the $400 range, such as the Sous Vide Supreme. While still on the expensive side, as a piece of consumer kitchen equipment, it's not unreasonable, and prices will inevitably fall. Given the versatility and usefulness of the cooking technique, definitely consider looking at this category of products. See http://www.cookingforgeeks.com/book/sousvidegear/ for suggestions on current products. for suggestions on current products.

DIY sous vide. Other commercial products supply the "sous vide logic" but are BYOHS (bring your own heat source). Appliances like slow cookers contain the necessary cooking parts already: they hold a reservoir of liquid, have a heating element, and are designed to run for extended periods of time. You can repurpose them for sous vide cooking by adding an external controller that switches the slow cooker on and off to keep it near a target temperature. See the sidebar on making your own sous vide rig for details. Other commercial products supply the "sous vide logic" but are BYOHS (bring your own heat source). Appliances like slow cookers contain the necessary cooking parts already: they hold a reservoir of liquid, have a heating element, and are designed to run for extended periods of time. You can repurpose them for sous vide cooking by adding an external controller that switches the slow cooker on and off to keep it near a target temperature. See the sidebar on making your own sous vide rig for details.

Make Your Own Sous Vide SetupIf you're the type inclined to fiddle with electronics, you can build your own sous vide rig by ordering a few parts online and spending a few hours tinkering.The actual electronics necessary to maintain a water bath at a set temperature are simple enough: a basic slow cooker, a thermocouple, and a simple thermostat controller to switch the heat source on and off.First, the slow cooker. The slow cooker will serve as the brawn, holding the water and providing the heat source. Snag a cheap slow cooker-you need one that will turn back on after losing power. Look for one that has a physical k.n.o.b; the digital ones reset and stay off after power has been cut and then restored. The slow cooker will serve as the brawn, holding the water and providing the heat source. Snag a cheap slow cooker-you need one that will turn back on after losing power. Look for one that has a physical k.n.o.b; the digital ones reset and stay off after power has been cut and then restored.[image]Next, the thermocouple. If you have a standard kitchen probe thermometer (which you really should), the probe-long braided cable, metal probe-is a thermocouple. For a sous vide rig, you'll need a type J thermocouple, which is made of materials that give it good sensitivity in the temperature ranges of sous vide cooking. This should cost around $15 to $20; search online for "type J probe" or search for part 3AEZ9 on on If you have a standard kitchen probe thermometer (which you really should), the probe-long braided cable, metal probe-is a thermocouple. For a sous vide rig, you'll need a type J thermocouple, which is made of materials that give it good sensitivity in the temperature ranges of sous vide cooking. This should cost around $15 to $20; search online for "type J probe" or search for part 3AEZ9 on on http://www.grainger.com.Finally, the temperature controller. Just about any thermocouple-based temperature switch will work; look for one that runs off 12 volts DC, such as Love Industries' TCS-4030, which runs about $75. Snag a 12-volt wall wart (AC/DC power adaptor) while you're at it. Just about any thermocouple-based temperature switch will work; look for one that runs off 12 volts DC, such as Love Industries' TCS-4030, which runs about $75. Snag a 12-volt wall wart (AC/DC power adaptor) while you're at it.Once you have all the parts on hand, it's a relatively straightforward procedure to perform the lobotomy on the slow cooker: hook the thermocouple up to the probe inputs on the switch and connect the 12-volt power supply to the switch, then snip the slow cooker's electrical cord and run one side of it through the switch. Create a small hole in the lid of the slow cooker and poke the thermocouple through. Make sure you use enough water in the slow cooker that the thermocouple makes contact with the water when the lid is on![image]

Vacuum packers Regardless of what type of vacuum packer you use, make sure that the plastic bag you're using is heat-stable.

Commercial in-chamber vacuum sealers. The industrial vacuum sealers create a (mostly) air-free chamber (a true vacuum). Unfortunately, they cost thousands of dollars. Fortunately, you don't need one. While there are a number of handy applications for them ( The industrial vacuum sealers create a (mostly) air-free chamber (a true vacuum). Unfortunately, they cost thousands of dollars. Fortunately, you don't need one. While there are a number of handy applications for them (mmm, watermelon steak), sous vide doesn't require this level of vacuum seal.