On Food And Cooking Part 19

Cooked sausages are heated as part of their production, and can be bought and eaten without further cooking for several days, or longer if they've been partly dried or smoked. But they're often cooked again just before eating. They can be made from the usual mixture of meat and fat, or from a number of other materials that thicken on cooking. The French white sausage, boudin blanc, boudin blanc, is made from various white meats bound together with milk, eggs, bread crumbs, or flour, while the black is made from various white meats bound together with milk, eggs, bread crumbs, or flour, while the black boudin noir boudin noir contains no meat at all: it's around one-third pork fat, one-third onions, apples, or chestnuts, and one-third pork blood, which coagulates during poaching to help provide a solid matrix. Liver sausage is made by cooking a blend of finely ground liver and fat. Manufacturers often use soy protein and nonfat milk solids to help thicken and retain moisture. contains no meat at all: it's around one-third pork fat, one-third onions, apples, or chestnuts, and one-third pork blood, which coagulates during poaching to help provide a solid matrix. Liver sausage is made by cooking a blend of finely ground liver and fat. Manufacturers often use soy protein and nonfat milk solids to help thicken and retain moisture.

Emulsified Sausages Emulsified sausages are a special kind of cooked sausage, best known in the form of frankfurters or wieners and so called for their presumed origins in Germany (Frankfurt) or Austria (Wien). Italian mortadella ("bologna") is similar. These sausages have a very fine-textured, h.o.m.ogeneous, tender interior, and a relatively mild flavor. They're made by combining pork, beef, or poultry with fat, salt, nitrite, flavorings, and usually additional water, and shearing the ingredients together in a large blender until they form a smooth "batter," which is similar to an emulsified sauce like mayonnaise (p. 625): the fat is evenly dispersed in small droplets, which are surrounded and stabilized by fragments of the muscle cells and by salt-dissolved muscle proteins. The temperature during blending is critical: if it rises above 60F/16C in a pork batter, 70F/21C in beef, the emulsion will be unstable and leak fat. The batter is then extruded into a casing and cooked to about 160F/70C. Heat coagulates the meat proteins and turns the batter into a cohesive, solid ma.s.s from which the casing can be removed. Due to their relatively high water content, around 5055%, emulsified sausages are perishable and must be refrigerated. Emulsified sausages are a special kind of cooked sausage, best known in the form of frankfurters or wieners and so called for their presumed origins in Germany (Frankfurt) or Austria (Wien). Italian mortadella ("bologna") is similar. These sausages have a very fine-textured, h.o.m.ogeneous, tender interior, and a relatively mild flavor. They're made by combining pork, beef, or poultry with fat, salt, nitrite, flavorings, and usually additional water, and shearing the ingredients together in a large blender until they form a smooth "batter," which is similar to an emulsified sauce like mayonnaise (p. 625): the fat is evenly dispersed in small droplets, which are surrounded and stabilized by fragments of the muscle cells and by salt-dissolved muscle proteins. The temperature during blending is critical: if it rises above 60F/16C in a pork batter, 70F/21C in beef, the emulsion will be unstable and leak fat. The batter is then extruded into a casing and cooked to about 160F/70C. Heat coagulates the meat proteins and turns the batter into a cohesive, solid ma.s.s from which the casing can be removed. Due to their relatively high water content, around 5055%, emulsified sausages are perishable and must be refrigerated.

Sausage Ingredients: Fat and Casings The fat for sausage making is generally pork fat from under the skin of the animal's back. Pork fat has the advantage of being relatively neutral in flavor, and back fat in particular has just the right consistency: hard enough not to melt and separate as the meat is ground or stored at warm room temperatures, but soft enough that it's not granular and pasty when eaten cool. Belly fat is softer than ideal, kidney fat and beef and lamb fat harder; poultry fats are too soft. In standard nonemulsified sausages, the 30%+ fat content helps separate the meat fragments and provides tenderness and moistness. The coa.r.s.er the meat fragments, the lower the surface area that fat must lubricate, and so the less fat required for an appealing texture (as little as 15%). The fat for sausage making is generally pork fat from under the skin of the animal's back. Pork fat has the advantage of being relatively neutral in flavor, and back fat in particular has just the right consistency: hard enough not to melt and separate as the meat is ground or stored at warm room temperatures, but soft enough that it's not granular and pasty when eaten cool. Belly fat is softer than ideal, kidney fat and beef and lamb fat harder; poultry fats are too soft. In standard nonemulsified sausages, the 30%+ fat content helps separate the meat fragments and provides tenderness and moistness. The coa.r.s.er the meat fragments, the lower the surface area that fat must lubricate, and so the less fat required for an appealing texture (as little as 15%).

Sausage casings were traditionally various parts of the animal digestive tube. Today, most "natural" casings are the thin connective-tissue layers of hog or sheep intestine, stripped of their inner lining and outer muscular layers by heat and pressure, partly dried and packed in salt until they're filled. (Beef casings include some muscle.) There are also manufactured sausage containers made from animal collagen, plant cellulose, and paper.

Cooking Fresh Sausages Since their fragmented interior guarantees a certain kind of tenderness, sausages are often cooked very casually. But they benefit from being heated as carefully as other fresh meats. Five centuries ago, Platina remarked on the need to cook liver sausage gently (see box, p. 169), and said that another sausage was called Since their fragmented interior guarantees a certain kind of tenderness, sausages are often cooked very casually. But they benefit from being heated as carefully as other fresh meats. Five centuries ago, Platina remarked on the need to cook liver sausage gently (see box, p. 169), and said that another sausage was called mortadella mortadella "because it is surely more pleasant a little raw than overcooked." Fresh sausages should be thoroughly cooked to kill microbes, but no hotter than well-done meat, or 160F/70C. Gentle cooking prevents the interior from reaching the boil, at which point the skin will burst and leak moisture and flavor, and which hardens the texture. Intentionally piercing the skin will release moisture throughout the cooking, but provides insurance against more disfiguring splitting toward the end. "because it is surely more pleasant a little raw than overcooked." Fresh sausages should be thoroughly cooked to kill microbes, but no hotter than well-done meat, or 160F/70C. Gentle cooking prevents the interior from reaching the boil, at which point the skin will burst and leak moisture and flavor, and which hardens the texture. Intentionally piercing the skin will release moisture throughout the cooking, but provides insurance against more disfiguring splitting toward the end.

Pates and Terrines Most medieval European cookbooks offer several recipes for meat pies, in which chopped meat and fat are cooked inside a pastry crust or in a well-greased earthenware pot. Over the centuries, French cooks refined this preparation, while in other countries it survived in rustic forms. And so England has pasties and patties, France the pate and the terrine. These last two terms are largely synonymous, though today "pate" usually suggests a fairly uniform and fine-textured mixture based on liver, "terrine" a coa.r.s.er, often patterned one. Pates and terrines thus span a wonderful range, from coa.r.s.e, rustic ma.s.sings of pork innards and head in the French pate de campagne, to luxurious layerings of brandy-scented foie gras and truffles.

Modern pates and terrines often contain little fat, but traditional mixes were based on a meat to fat ratio of around 2 to 1 to give a rich, melt-in-the-mouth consistency. Pork and veal, an immature meat with relatively little tough connective tissue and an abundant producer of gelatin, are the usual main ingredients. They are ground together with the fat - usually pork for its ideal consistency - to mix protein and fat intimately. Hand chopping is less likely to heat the mixture or damage intact fat cells, which would cause more liquid fat to separate from the mix during cooking. The mix is seasoned more strongly than many foods both because it's rich in flavor-binding proteins and fats, and because it's generally served cool, which reduces the aroma. The mix is placed in a mold, covered, and cooked gently in a water bath until the juices run clear and the internal temperature reaches 160F/70C. (Terrines of foie gras are often cooked to a much lower temperature, perhaps 120F/55C, especially if intact lobes are layered together; they come out rosy pink.) The proteins have coagulated into a solid matrix, trapping much of the fat in place. The pate is then topped with a weight to compact it, and refrigerated for several days to firm and allow the flavors to blend. The cooked mixture keeps for about a week.

Pates and Terrines: Early RecipesAs these medieval recipes demonstrate, even early pates were made in pots and dishes without the pastry that originally gave them their name.Pastez de beufTake good young beef, and remove all fat. Cut the lean into pieces and boil, and afterwards take to the pastry cook to be chopped, and fatten it with beef marrow.- Le Menagier de Paris, Le Menagier de Paris, ca. 1390 ca. 1390Pastilli di carneTake as much lean meat as you want and cut it up fine with small knives. Mix veal fat and spices into this meat. Wrap in crusts and bake in an oven.... This can even be made in a well-greased dish without a crust.- Maestro Martino, ca. 1450 Preserved Meats The preservation of meat from biological spoilage has been a major challenge throughout human history. The earliest methods, which go back at least 4,000 years, were physical and chemical treatments that make meat inhospitable to microbes. Drying meat in the sun and wind or by the fire removes enough water to halt bacterial growth. A smoky fire deposits cell-killing chemicals on the meat surface. Heavy salting - with partly evaporated seawater, or rock salt, or the ashes of salt-concentrating plants - also draws vital moisture from cells. Moderate salting permits the growth of a few hardy and harmless microbes that help exclude harmful ones. Out of these crude methods to stave off spoilage have come some of our most complex and interesting foods, the dry-cured hams and fermented sausages.

The Industrial Revolution brought a new approach: preserve meat not by changing the meat itself, but by controlling its environment. Canning encloses cooked meat in a sterile container hermetically sealed against the entry of microbes. Mechanical refrigeration and freezing keep meat cold enough to slow microbial growth or suspend it altogether. And irradiation of prepackaged meat kills any microbes in the package while leaving the meat itself relatively unchanged.

Dried Meats: Jerky Microbes need water to survive and grow, so one simple and ancient preservation technique has been to dry meat, originally by exposing it to the wind and sun. Nowadays, meat is dried by briefly salting it to inhibit surface microbes and then heating it in low-temperature convection ovens to remove at least two-thirds of its weight and 75% of its moisture (more than 10% moisture may allow Penicillium Penicillium and and Aspergillus Aspergillus molds to grow). Because its flavor has been concentrated and its texture is interesting, dried meat remains popular. Modern examples include American jerky, Latin American molds to grow). Because its flavor has been concentrated and its texture is interesting, dried meat remains popular. Modern examples include American jerky, Latin American carne seca, carne seca, Norwegian Norwegian fenalr fenalr and southern African and southern African biltong, biltong, whose textures can range from chewy to brittle. Two refined versions are Italian whose textures can range from chewy to brittle. Two refined versions are Italian bresaola bresaola and Swiss and Swiss Buendnerfleisch, Buendnerfleisch, which are beef salted and sometimes flavored with wine and herbs before a slow, cool drying period of up to several months. They're served in paper-thin slices. which are beef salted and sometimes flavored with wine and herbs before a slow, cool drying period of up to several months. They're served in paper-thin slices.

Freeze-Drying Freeze-drying is the technique originally used by Andean peoples to make Freeze-drying is the technique originally used by Andean peoples to make charqui charqui; they took advantage of the thin dry air to evaporate moisture from meat during sunny days and sublimate it from ice crystals during freezing nights. The result was an uncooked, honeycombed tissue that would readily reabsorb water during later cooking. In the industrial version, the meat is rapidly frozen under vacuum, then mildly heated to sublimate its water. Because this kind of desiccation doesn't cause cooking and compaction of the tissue, relatively thick pieces can be dried and reconst.i.tuted.

Salted Meats: Hams, Bacon, Corned Beef Like drying, salting preserves meat by depriving bacteria and molds of water. The addition of salt - sodium chloride - to meat creates such a high concentration of dissolved sodium and chloride ions outside the microbes that water inside their cells is drawn out, salt is drawn in, and their cellular machinery is disrupted. The microbes either die or slow down drastically. The muscle cells too are partly dehydrated and absorb salt. Traditional cured meats, made by dry-salting or brining large cuts for several days, are about 60% moisture and 57% salt by weight. The resulting hams (from pig legs), bacon (from pig sides), corned beef ("corn" coming from the English word for grains, including salt grains), and similar products keep uncooked for many months.

Useful Impurities: Nitrates and Nitrites Sodium chloride is not the only salt with an important role in salt-curing. The others were unpredictable mineral impurities in the rock, sea, and vegetable salts originally used for curing. One of these, pota.s.sium nitrate (KNO Sodium chloride is not the only salt with an important role in salt-curing. The others were unpredictable mineral impurities in the rock, sea, and vegetable salts originally used for curing. One of these, pota.s.sium nitrate (KNO3), was discovered during the Middle Ages and named saltpeter saltpeter because it was found as a salt-like crystalline outgrowth on rocks. In the 16th or 17th century, it was found to brighten meat color and improve its flavor, safety, and storage life. Around 1900, German chemists discovered that during the cure certain salt-tolerant bacteria transform a small portion of the nitrate into nitrite (NO because it was found as a salt-like crystalline outgrowth on rocks. In the 16th or 17th century, it was found to brighten meat color and improve its flavor, safety, and storage life. Around 1900, German chemists discovered that during the cure certain salt-tolerant bacteria transform a small portion of the nitrate into nitrite (NO2), and that nitrite rather than nitrate is the true active ingredient. Once this was known, producers could eliminate saltpeter from the curing mixture and replace it with much smaller doses of pure nitrite. This is now the rule except in the production of traditional dry-cured hams and bacons, where prolonged ripening benefits from the ongoing bacterial production of nitrite from nitrate.

We now know that nitrite does several important things for cured meats. It contributes its own sharp, piquant flavor. It reacts in the meat to form nitric oxide (NO), which r.e.t.a.r.ds the development of rancid flavors in the fat by preemptively binding to the iron atom in myoglobin, thus preventing the iron from causing fat oxidation. The same iron binding produces the characteristic bright pink-red color of cured meat. Finally, nitrite suppresses the growth of various bacteria, most importantly the spores of the oxygen-intolerant bacterium that causes deadly botulism. Clostridium botulinum Clostridium botulinum can grow inside sausages that have been insufficiently or unevenly salted; German scientists first named the poisoning it causes can grow inside sausages that have been insufficiently or unevenly salted; German scientists first named the poisoning it causes Wurstvergiftung, Wurstvergiftung, or sausage disease ( or sausage disease (botulus is Latin for sausage). Nitrite apparently inhibits important bacterial enzymes and interferes with energy production. is Latin for sausage). Nitrite apparently inhibits important bacterial enzymes and interferes with energy production.

Traditional Versions of Cured PorkOf curing hams: This is the way to cure hams in jars or tubs.... Cover the bottom of the jar or tub with salt and put in a ham, skin down. Cover the whole with salt and put another ham on top, and cover this in the same manner. Be careful that meat does not touch meat. So proceed, and when you have packed all the hams, cover the top with salt so that no meat can be seen, and smooth it out even. When the hams have been in salt five days, take them all out with the salt and repack them, putting those which were on top at the bottom....After the twelfth day remove the hams, brush off the salt, and hang them for two days in the wind. On the third day wipe them off clean with a sponge and rub them with oil. Then hang them in smoke for two days, and on the third day rub them with a mixture of vinegar and oil.Then hang them in the meat house, and neither bats nor worms will touch them.- Cato, On Agriculture On Agriculture, 50 BCE BCEBacon, to dry: Cut the Leg with a piece of the Loin (of a young Hog) then with Saltpeter, in fine Pouder and brown Sugar mix'd together, rub it well daily for 2 or 3 days, after which salt it well; so will it look red: let it lye for 6 or 8 Weeks, then hang it up (in a drying-place) to dry.- William Salmon, The Family Dictionary: Or, Household Companion The Family Dictionary: Or, Household Companion, London, 1710 Nitrate and nitrite can react with other food components to form possible cancer-causing nitrosamines. This risk now appears to be small (p. 125). Nevertheless, residual nitrate and nitrite in cured meats is limited to 200 parts per million (0.02%) in the United States, and is usually well below this limit.

Sublime Hams The many months that salted meats keep turned out to transform pig flesh into some of the great foods of the world! First among them are the dry-cured hams, which go back at least to cla.s.sical times. The modern versions, which include Italian prosciutto di Parma, Spanish serrano, French Bayonne, and American country hams, may be aged for a year or more. Though they can be cooked, dry-cured hams are at their best when eaten in paper-thin raw slices. With their vivid, rose-colored translucency, silken texture, and a flavor at once meaty and fruity, they are to fresh pork what long-aged cheeses are to fresh milk: a distillation, an expression of the transforming powers of salt, enzymes, and time. The many months that salted meats keep turned out to transform pig flesh into some of the great foods of the world! First among them are the dry-cured hams, which go back at least to cla.s.sical times. The modern versions, which include Italian prosciutto di Parma, Spanish serrano, French Bayonne, and American country hams, may be aged for a year or more. Though they can be cooked, dry-cured hams are at their best when eaten in paper-thin raw slices. With their vivid, rose-colored translucency, silken texture, and a flavor at once meaty and fruity, they are to fresh pork what long-aged cheeses are to fresh milk: a distillation, an expression of the transforming powers of salt, enzymes, and time.

The Effects of Salt In addition to protecting hams from spoilage as they mature, salt contributes to their appearance and texture. High salt concentrations cause the normally tightly bunched protein filaments in the muscle cells to separate into individual filaments, which are too small to scatter light: so the normally opaque muscle tissue becomes translucent. The same unbunching also weakens the muscle fibers, while at the same time dehydration makes the tissue denser and more concentrated: hence the close but tender texture. In addition to protecting hams from spoilage as they mature, salt contributes to their appearance and texture. High salt concentrations cause the normally tightly bunched protein filaments in the muscle cells to separate into individual filaments, which are too small to scatter light: so the normally opaque muscle tissue becomes translucent. The same unbunching also weakens the muscle fibers, while at the same time dehydration makes the tissue denser and more concentrated: hence the close but tender texture.

The Enigma of Hams Cured Without NitriteThough most traditional long-cured hams are treated with saltpeter to provide a steady supply of nitrite, a few are not. The eminent prosciuttos of Parma and San Daniele are cured with sea salt only, yet somehow still develop the characteristic rosy color of nitrite-stabilized myoglobin. Sea salt does contain nitrate and nitrite impurities, but not enough to affect ham color. Recently, j.a.panese scientists found that the stable red pigment of these hams is not nitrosomyoglobin, and its formation seems a.s.sociated with the presence of particular ripening bacteria (Staphylococcus carnosus and and caseolyticus caseolyticus). And it may be that the absence of nitrite is one of the keys to the exceptional quality of these hams. Nitrite protects meat fats from oxidation and the development of off-flavors. But fat breakdown is also one of the sources of desirable ham flavor, and nitrite-free Parma hams have been found to contain more fruity esters than nitrite-cured Spanish and French hams.

The Alchemy of Dry-Cured Flavor Some of the muscles' biochemical machinery survives intact, in particular the enzymes that break flavorless proteins down into savory peptides and amino acids, which over the course of months may convert a third or more of the meat protein to flavor molecules. The concentration of mouth-filling, meaty glutamic acid rises ten- to twenty-fold, and as in cheese, so much of the amino acid tyrosine is freed that it may form small white crystals. In addition, the unsaturated fats in pig muscle break apart and react to form hundreds of volatile compounds, some of them characteristic of the aroma of melon (a traditional and chemically fitting accompaniment to ham!), apple, citrus, flowers, freshly cut gra.s.s, and b.u.t.ter. Other compounds react with the products of protein breakdown to give nutty, caramel flavors normally found only in cooked meats (concentration compensates for the subcooking temperature). In sum, the flavor of dry-cured ham is astonis.h.i.+ngly complex and evocative. Some of the muscles' biochemical machinery survives intact, in particular the enzymes that break flavorless proteins down into savory peptides and amino acids, which over the course of months may convert a third or more of the meat protein to flavor molecules. The concentration of mouth-filling, meaty glutamic acid rises ten- to twenty-fold, and as in cheese, so much of the amino acid tyrosine is freed that it may form small white crystals. In addition, the unsaturated fats in pig muscle break apart and react to form hundreds of volatile compounds, some of them characteristic of the aroma of melon (a traditional and chemically fitting accompaniment to ham!), apple, citrus, flowers, freshly cut gra.s.s, and b.u.t.ter. Other compounds react with the products of protein breakdown to give nutty, caramel flavors normally found only in cooked meats (concentration compensates for the subcooking temperature). In sum, the flavor of dry-cured ham is astonis.h.i.+ngly complex and evocative.

Modern Wet-Cured Meats Salted meats continue to be popular even in the age of refrigeration, when salting is no longer essential. But because we now salt meats for taste, not to extend storage life, industrial versions are treated with milder cures, and generally must be refrigerated and/or cooked. And they're made very quickly, which means that their flavor is less complex than dry-cured meats. Industrial bacon is made by injecting brine (typically about 15% salt, 10% sugar) into the pork side with arrays of fine needles, or else cutting it into slices, then immersing the slices in a brine for 10 or 15 minutes. In either method the "maturing" period has shrunk to a few hours, and the bacon is packed the same day. Hams are injected with brine, then "tumbled" in large rotating drums for a day to ma.s.sage the brine evenly through the meat and make it more supple, and finally pressed into shape, partly or fully cooked, chilled, and sold with no maturing period. For some boneless "hams," pork pieces are tumbled with salt to draw out the muscle protein myosin, which forms a sticky layer that holds the pieces together. Most corned beef is now injected with brine as well; the briskets never touch any actual salt grains. Salted meats continue to be popular even in the age of refrigeration, when salting is no longer essential. But because we now salt meats for taste, not to extend storage life, industrial versions are treated with milder cures, and generally must be refrigerated and/or cooked. And they're made very quickly, which means that their flavor is less complex than dry-cured meats. Industrial bacon is made by injecting brine (typically about 15% salt, 10% sugar) into the pork side with arrays of fine needles, or else cutting it into slices, then immersing the slices in a brine for 10 or 15 minutes. In either method the "maturing" period has shrunk to a few hours, and the bacon is packed the same day. Hams are injected with brine, then "tumbled" in large rotating drums for a day to ma.s.sage the brine evenly through the meat and make it more supple, and finally pressed into shape, partly or fully cooked, chilled, and sold with no maturing period. For some boneless "hams," pork pieces are tumbled with salt to draw out the muscle protein myosin, which forms a sticky layer that holds the pieces together. Most corned beef is now injected with brine as well; the briskets never touch any actual salt grains.

Modern ham and bacon contain more moisture than the dry-cured versions (sometimes more than the original raw meat!) and about half the salt - 34% instead of 57%. Where slices of traditional ham and bacon fry easily and retain 75% of their weight, the wetter modern versions spatter, shrink, and curl as they give up their water, and retain only a third of their initial weight.

Smoked Meats Smoke from burning plant materials, usually wood, has helped to preserve food ever since our ancestors mastered fire. Smoke's usefulness results from its chemical complexity (p. 448). It contains many hundreds of compounds, some of which kill or inhibit the growth of microbes, some of which r.e.t.a.r.d fat oxidation and the development of rancid flavors, and some of which add an appealing flavor of their own. Because smoke only affects the surface of food, it has long been used in conjunction with salting and drying - a happy combination because salted meats are especially p.r.o.ne to developing rancidity. American country hams and bacons are examples of smoked salted foods. Because there are now other ways to store meat, and because some smoke components are known to be health hazards (p. 449), smoke is now used less frequently as a full-strength preservative, and more often as a lightly applied flavoring.

Hot and Cold Smoking Meat can be smoked in two different ways. When Meat can be smoked in two different ways. When hot-smoked, hot-smoked, the meat is held directly above or in the same enclosure as the wood, and therefore cooks while it's smoked. This will give it a more or less firm, dry texture, depending on the temperature (usually between 130 and 180F/5580C) and time involved, and can kill microbes throughout the meat, not just on the surface. (Barbecuing is a form of hot smoking; see p. 157.) When it is the meat is held directly above or in the same enclosure as the wood, and therefore cooks while it's smoked. This will give it a more or less firm, dry texture, depending on the temperature (usually between 130 and 180F/5580C) and time involved, and can kill microbes throughout the meat, not just on the surface. (Barbecuing is a form of hot smoking; see p. 157.) When it is cold-smoked, cold-smoked, the meat is held in an unheated chamber through which smoke is pa.s.sed from a separate firebox. The texture of the meat, and any microbes within it, are relatively unaffected. The cold-smoking chamber may be as low as 32F/0C but more usually ranges between 60 and 80F/1525C. Smoke vapors are deposited onto the meat surface as much as seven times faster in hot smoking; however, cold-smoked meats tend to acc.u.mulate higher concentrations of the sweet-spicy phenolic components and so may have a finer flavor. (They also tend to acc.u.mulate more possible carcinogens.) The humidity of the air also makes a difference; smoke vapors are deposited most efficiently onto moist surfaces, so "wet" smoking has a stronger effect in a shorter time. the meat is held in an unheated chamber through which smoke is pa.s.sed from a separate firebox. The texture of the meat, and any microbes within it, are relatively unaffected. The cold-smoking chamber may be as low as 32F/0C but more usually ranges between 60 and 80F/1525C. Smoke vapors are deposited onto the meat surface as much as seven times faster in hot smoking; however, cold-smoked meats tend to acc.u.mulate higher concentrations of the sweet-spicy phenolic components and so may have a finer flavor. (They also tend to acc.u.mulate more possible carcinogens.) The humidity of the air also makes a difference; smoke vapors are deposited most efficiently onto moist surfaces, so "wet" smoking has a stronger effect in a shorter time.

Fermented Meats: Cured Sausages Milk is transformed into long-keeping and flavorful cheese by removing some of its moisture, salting it, and encouraging harmless microbes to grow in and acidify it: and meat can be be treated in much the same way to the same effect. There are many different kinds of sausage, sausage, or re-formed ma.s.ses of chopped, salted meat (p. 169). Fermented sausages are the most flavorful thanks to bacteria that break down bland proteins and fats into smaller, intensely savory and aromatic molecules. or re-formed ma.s.ses of chopped, salted meat (p. 169). Fermented sausages are the most flavorful thanks to bacteria that break down bland proteins and fats into smaller, intensely savory and aromatic molecules.

Fermented sausages probably developed in prehistoric times from the practice of salting and drying meat sc.r.a.ps to preserve them. When salted sc.r.a.ps are squeezed together, microbe-laden surfaces end up inside the moist ma.s.s, and salt-tolerant bacteria that can grow without oxygen thrive there. For the most part, these bacteria turn out to be the same ones that can grow in salty, air-poor cheese: namely the Lactobacilli and Leuconostocs (and such relatives as the Micrococci, Pediococci, and Carn.o.bacteria). They produce lactic and acetic acids, which lower the meat pH from 6 to 4.55 and make it even less hospitable to spoilage microbes. Then, as the sausage slowly dries out with time, the salt and acidity become more concentrated, and the sausage increasingly resistant to spoilage.

Southern and Northern Styles of Sausage Fermented sausages come in two general styles. One is the dry, salty, well-spiced sausage typical of the warm, dry Mediterranean. Italian salami and Spanish and Portuguese chorizos are 2535% water, contain more than 4% salt, and can be stored at room temperature. The other style is the moister, less salty, usually smoked and/or cooked sausage typical of northern Europe, whose cool, humid climate made drying difficult. These "summer" sausages and German cervelats are 4050% water, around 3.5% salt, and must be refrigerated. Both can be eaten uncooked. Fermented sausages come in two general styles. One is the dry, salty, well-spiced sausage typical of the warm, dry Mediterranean. Italian salami and Spanish and Portuguese chorizos are 2535% water, contain more than 4% salt, and can be stored at room temperature. The other style is the moister, less salty, usually smoked and/or cooked sausage typical of northern Europe, whose cool, humid climate made drying difficult. These "summer" sausages and German cervelats are 4050% water, around 3.5% salt, and must be refrigerated. Both can be eaten uncooked.

Making Fermented Sausages These days, nitrates (Europe) or nitrites (U.S.) to suppress botulism bacteria are added to the mix of meat, fat, bacterial culture, salt, and spices, as is some sugar, at least part of which the bacteria transform into lactic acid. Fermentation lasts from 18 hours to three days, depending on temperature (60100F/1538C, with dry sausages at the low end) and sausage size, until the acidity reaches 1%, the pH 4.55. High-temperature fermentation tends to produce volatile acids (acetic, butanoic) with a sharp aroma, while low-temperature fermentation produces a more complex blend of nutty aldehydes and fruity esters (the traditional salami flavor). The sausage may then be cooked and/or smoked, and finally is dried for two to three weeks to the desired final moisture content. A powdery white coat of harmless molds and yeasts (species of These days, nitrates (Europe) or nitrites (U.S.) to suppress botulism bacteria are added to the mix of meat, fat, bacterial culture, salt, and spices, as is some sugar, at least part of which the bacteria transform into lactic acid. Fermentation lasts from 18 hours to three days, depending on temperature (60100F/1538C, with dry sausages at the low end) and sausage size, until the acidity reaches 1%, the pH 4.55. High-temperature fermentation tends to produce volatile acids (acetic, butanoic) with a sharp aroma, while low-temperature fermentation produces a more complex blend of nutty aldehydes and fruity esters (the traditional salami flavor). The sausage may then be cooked and/or smoked, and finally is dried for two to three weeks to the desired final moisture content. A powdery white coat of harmless molds and yeasts (species of Penicillium, Candida, Debaromyces Penicillium, Candida, Debaromyces) may develop on the casing during drying; these microbes contribute to flavor and prevent the growth of spoilage microbes.

Fermented sausages develop a dense, chewy texture thanks to the salt extraction of the meat proteins, their denaturation by the bacterial acids, and to the general drying of the meat ma.s.s. Their tangy, aromatic flavor comes from the bacterial acids and volatile molecules, and from fragments of protein and fat generated by enzymes from both the microbes and the meat.

Confits In ancient times, cooks from central Asia to western Europe learned that cooked meat could be preserved by burying it under a thick, airtight seal of fat. Today the best known version is the southwest French confit confit of goose and duck legs, which became fas.h.i.+onable in the 19th century on the coattails of foie gras - which may in turn have been an accidental by-product of cramming geese to get the fat for unfas.h.i.+onable farmhouse confits! The French confit probably began as a household method for preserving pork in its own lard through the year following the autumn slaughter. The confit of goose and duck seems to have been developed by makers of salted meats around Bayonne in the 18th century, when local maize production made it economical to force-feed fowl and generate the necessary fat. In the age of canning and refrigeration, confits are still made as a convenient, long-keeping ingredient that lends its distinctive flavor to salads, stews, and soups. of goose and duck legs, which became fas.h.i.+onable in the 19th century on the coattails of foie gras - which may in turn have been an accidental by-product of cramming geese to get the fat for unfas.h.i.+onable farmhouse confits! The French confit probably began as a household method for preserving pork in its own lard through the year following the autumn slaughter. The confit of goose and duck seems to have been developed by makers of salted meats around Bayonne in the 18th century, when local maize production made it economical to force-feed fowl and generate the necessary fat. In the age of canning and refrigeration, confits are still made as a convenient, long-keeping ingredient that lends its distinctive flavor to salads, stews, and soups.

The traditional French confit is made by salting pieces of meat for a day, sometimes along with herbs and spices, then drying them, immersing them in fat, and heating very gradually and gently for several hours. The meat, often still pink or red inside (p. 149), is then drained, placed in a sterilized container over an additional sprinkling of salt, the fat skimmed from any spoilage-p.r.o.ne meat juices, reheated, and then poured over the meat. Sealed and stored in a cool place, the confit keeps for several months, and can be reheated periodically to extend its useful life.

The small but real risk that botulism bacteria could grow in this low-oxygen environment is reduced by the second dose of salt, by storage temperatures below 40F/4C, and by the addition of nitrate or nitrite to the salt. Most modern versions of the confit are either canned or are refrigerated for safety and made to be eaten within a few days, so they're salted mildly, more for flavor and color than for preservation.

The flavor of a traditional confit is said to improve over the course of several months. Though the cooking presumably kills bacteria and inactivates all enzymes in the meat, there will certainly be biochemical changes in the meat over time, and the fat will oxidize. A slight rancidity is part of the flavor of a traditional confit.

Food Words: Confit ConfitThese days the word confit confit is used loosely to describe just about anything cooked slowly and gently to a rich, succulent consistency: onions in olive oil, for example, or shrimp cooked and stored under clarified b.u.t.ter. In fact the term is a fairly inclusive one. It comes via the French verb is used loosely to describe just about anything cooked slowly and gently to a rich, succulent consistency: onions in olive oil, for example, or shrimp cooked and stored under clarified b.u.t.ter. In fact the term is a fairly inclusive one. It comes via the French verb confire confire, from the Latin conficere, conficere, meaning "to do, to produce, to make, to prepare." The French verb was first applied in medieval times to fruits cooked and preserved in sugar syrup or honey (hence French meaning "to do, to produce, to make, to prepare." The French verb was first applied in medieval times to fruits cooked and preserved in sugar syrup or honey (hence French confiture confiture and English and English confection confection) or in alcohol. Later it was applied to vegetables pickled in vinegar, olives in oil, various foods in salt, and meats under fat. The general sense has been to immerse a food in and often impregnate it with a substance that both flavors it and preserves it. In modern usage of the term confit, confit, the connotations of immersion, impregnation, flavoring, and slow, deliberate preparation survive, while the idea of preservation - and the special flavors that develop over weeks and months - has faded away. the connotations of immersion, impregnation, flavoring, and slow, deliberate preparation survive, while the idea of preservation - and the special flavors that develop over weeks and months - has faded away.

Canned Meats Around 1800, a French brewer and confectioner named Nicolas Appert discovered that if he sealed food in a gla.s.s container and then heated the container in boiling water, the food would keep indefinitely without spoiling. This was the beginning of canning, a form of preservation in which the food is first isolated from air and external contamination by microbes, and then heated sufficiently to destroy any microbes already in the food. (Pasteur hadn't yet proven the existence of microbes; Appert simply observed that all "ferments" were destroyed in his process.) When done properly, canning is quite effective: canned meat a century old has been eaten without harm, if also without much pleasure. The canning of meats is almost exclusively an industrial process today, in part because it offers the cook little in the way of desirable flavors or textures.

Chapter 4.

Fish and Sh.e.l.lfish

Fisheries and Aquaculture Advantages and Drawbacks of Aquaculture Seafood and Health Health BenefitsHealth Hazards Life in Water and the Special Nature of Fish The Paleness and Tenderness of Fish FleshThe Flavor of Fish and Sh.e.l.lfishThe Healthfulness of Fish OilsThe Perishability of Fish and Sh.e.l.lfishThe Sensitivity and Fragility of Fish in the PanThe Unpredictability of Fish Quality The Anatomy and Qualities of Fish Fish AnatomyFish Muscle and Its Delicate TextureFish FlavorFish Color The Fish We Eat The Herring Family: Anchovy, Sardine, Sprat, ShadCarp and CatfishSalmons, Trouts, and RelativesThe Cod FamilyNile Perch and TilapiaBa.s.sesIcefishTunas and MackerelSwordfishFlatfish: Soles, Turbot, Halibuts, Flounders From the Waters to the Kitchen The HarvestThe Effects of Rigor Mortis and TimeRecognizing Fresh FishStoring Fresh Fish and Sh.e.l.lfish: Refrigeration and FreezingIrradiation Unheated Preparations of Fish and Sh.e.l.lfish Sus.h.i.+ and Sas.h.i.+miTart Ceviche and KinilawSalty Poke and Lomi Cooking Fish and Sh.e.l.lfish How Heat Transforms Raw FishPreparations for CookingTechniques for Cooking Fish and Sh.e.l.lfishFish Mixtures Sh.e.l.lfish and Their Special Qualities Crustaceans: Shrimps, Lobsters, Crabs, and RelativesMolluscs: Clams, Mussels, Oysters, Scallops, Squid, and RelativesOther Invertebrates: Sea Urchins Preserved Fish and Sh.e.l.lfish Dried FishSalted FishFermented FishSmoked FishFour-Way Preservation: j.a.panese Katsuobus.h.i.+Marinated FishCanned Fish Fish Eggs Salt Transforms Egg Flavor and TextureCaviar Fish and sh.e.l.lfish are foods from the earth's other world, its vast water underworld. Dry land makes up less than a third of the planet's surface, and it's a tissue-thin home compared to the oceans, whose floor plunges as much as 7 miles below the waves. The oceans are voluminous and ancient, the "primordial soup" in which all life began, and in which the human imagination has found rich inspiration for myths of destruction and creation, of metamorphosis and rebirth. The creatures that live in this cold, dark, dense, airless place are unmatched among our food animals in their variety and their strangeness.

Our species has long nourished itself on fish and sh.e.l.lfish, and it built nations on them as well. The world's coastlines are dotted with ma.s.sive piles of oyster and mussel sh.e.l.ls that commemorate feasts going back 300,000 years. By 40,000 years ago the hunters of prehistoric Europe were carving salmon images and making the first hooks to catch river fish; and not long afterward, they ventured onto the ocean in boats. From the late Middle Ages on, the seagoing nations of Europe and Scandinavia exploited the Atlantic's abundant stocks of cod and herring, drying and salting them into commodities that were the foundation of their modern prosperity.

Five hundred years later, at the beginning of the 21st century, the oceans' productivity is giving out. It has been exhausted by feeding a tenfold increase in the human population, and by constant advances in fis.h.i.+ng technology and efficiency. With the help of faster and larger s.h.i.+ps, sonar to see into the depths, miles-long nets and lines, and the mechanization of all aspects of the harvest, we've managed to fish many important food species to the verge of commercial extinction. Formerly common fish - cod and herring, Atlantic salmon and swordfish and sole, sturgeon and shark - are increasingly rare. Others - orange roughy, Chilean sea ba.s.s, monkfish - come and go from the market, temporarily abundant until they too are overfished.

The decline in the populations of wild fish has encouraged the widespread revival and modernization of aquaculture. Fish farms are now our nearly exclusive source for freshwater fish, for Atlantic salmon, and for mussels. Many of these operations effectively spare wild populations, but others further deplete them and cause environmental damage of their own. It takes some effort these days to find and choose fish and sh.e.l.lfish that have been produced in environmentally responsible, sustainable ways.

Yet it's a good time to be eating from the waters. More fish of excellent quality are available more widely than ever before, and they come from all over the globe, offering the opportunity to discover new ingredients and new pleasures. At the same time, their variety and variability make it challenging to choose and prepare them well. Fish and sh.e.l.lfish are more fragile and less predictable than ordinary meats. This chapter will take a close look at their special nature, and how they're best handled and prepared.

Brillat-Savarin on FishFish are an endless source of meditation and astonishment. The varied forms of these strange creatures, their diverse means of existence, the influence upon this of the places in which they must live and breathe and move about....- Physiology of Taste Physiology of Taste, 1825 Fisheries and Aquaculture Of all our foods, fish and sh.e.l.lfish are the only ones that we still harvest in significant quant.i.ties from the wild. The history of the world's fisheries is the saga of human ingenuity, bravery, hunger, and wastefulness evolving into a maw that now swallows much of the oceans' tremendous productivity. In 1883, the eminent biologist T. H. Huxley expressed his belief that "the cod fishery, the herring fishery, the pilchard fishery, the mackerel fishery, and probably all the great sea fisheries are inexhaustible; that is to say that nothing we do seriously affects the numbers of fish." Just over a century later, cod and herring stocks on both sides of the North Atlantic have collapsed, many other fish are in decline, and the U.N. Food and Agriculture Organization estimates that we are harvesting two-thirds of the major commercial fish in the world at or beyond the level at which they can sustain themselves.

In addition to dangerously depleting its target fish populations, modern fis.h.i.+ng causes collateral damage to other species, the "bycatch" of undiscriminating nets and lines that is simply discarded, and it can damage ocean-bottom habitats. Fis.h.i.+ng is also an unpredictable, dangerous job, subject to the uncertainties of weather and the hazards of working at sea with heavy equipment. To this highly problematic system of production, there is an increasingly important alternative: aquaculture, or fish farming, which in many parts of the world goes back thousands of years. Today in the United States, all of the rainbow trout and nearly all of the catfish sold are farmed on land in various kinds of ponds and tanks. Norway pioneered the ocean farming of Atlantic salmon in large offsh.o.r.e pens in the 1960s; and today more than a third of the salmon eaten in the world is farmed in Europe and North and South America. About a third of the world warm-water shrimp harvest is cultured, mainly in Asia. In all, about 70 species are now farmed worldwide.

Advantages and Drawbacks of Aquaculture There are several distinct advantages to aquaculture. Above all, it allows the producer unequaled control over the condition of the fish and the circ.u.mstances of the harvest, both of which can result in better quality in the market. Farmed fish can be carefully selected for rapid growth and other desirable characteristics, and raised to a uniform and ideal stage for eating. By adjusting water temperature and flow rate and light levels, fish can be induced to grow far more rapidly than in the wild, and a balance can be struck between energy consumption and muscle-toning exercise. Farmed fish are often fattier and so more succulent. They can be slaughtered without suffering the stress and physical damage of being hooked, netted, or dumped en ma.s.se on deck; and they can be processed and chilled immediately and cleanly, thus prolonging their period of maximum quality.

The Oceans' Silver StreamsFish...may seem a mean and a base commodity; yet who will but truly take the pains and consider the sequel, I think will allow it well worth the labour.... The poor Hollanders chiefly by fis.h.i.+ng at a great charge and labour in all weathers in the open sea,...are made so mighty, strong, and rich, as no state but Venice of twice their magnitude is so well furnished, with so many fair cities, goodly towns, strong fortresses.... The sea [is] the source of those silver streams of all their virtue, which hath made them now the very miracle of industry, the only pattern of perfection for these affairs...- Capt. John Smith, The Generall Historie of Virginia, New England, and the Summer Isles, The Generall Historie of Virginia, New England, and the Summer Isles, London, 1624 London, 1624 However, aquaculture is not a perfect solution to the problems of ocean fis.h.i.+ng, and has itself created a number of serious problems. Farming in offsh.o.r.e pens contaminates surrounding waters with wastes, antibiotics, and unconsumed food, and allows genetically uniform fish to escape and dilute the diversity of already endangered wild populations. The feed for carnivorous and scavenger species (salmon, shrimp) is mainly protein-rich fish meal, so some aquaculture operations actually consume wild fish rather than sparing them. And very recent studies have found that some environmental toxins (PCBs, p. 184) become concentrated in fish meal and are deposited in the flesh of farmed salmon.

A less serious problem, but one that makes a difference in the kitchen, is that the combination of limited water flow, limited exercise, and artificial feeds can affect the texture and flavor of farmed fish. In taste tests, farmed trout, salmon, and catfish are perceived to be blander and softer than their wild counterparts.

Modern aquaculture is still young, and ongoing research and regulation will certainly solve some of these problems. In the meantime, the most environmentally benign products of aquaculture are freshwater fish and a few salt.w.a.ter fish (sturgeon, turbot) farmed on land, and molluscs farmed on seacoasts. Concerned cooks and consumers can get up-to-date information about the health of fisheries and aquacultural practices from a number of public interest groups, including the Monterey Bay Aquarium in California.

Farmed Fish and Sh.e.l.lfishThese are some commonly available fish and sh.e.l.lfish that are being farmed on a commercial scale at the beginning of the 21st century.

Freshwater Fish 1. Carp 2. Tilapia 3. Catfish 4. Trout (rainbow) 5. Nile perch 6. Eel 7. Striped ba.s.s (hybrid) Salt.w.a.ter Fish 1. Salmon 2. Sea Ba.s.s 3. Sturgeon 4. Trout (steelhead) 5. Char 6. Turbot 7. Mahimahi 8. Milkfish 9. Yellowtail 10. Amberjack 11. Breams 12. Fugu 13. Tuna Molluscs 1. Abalone 2. Mussel 3. Oyster 4. Clam 5. Scallop Crustaceans 1. Shrimp 2. Crayfish Seafood and Health Fish is good for us: this belief is one important reason for the growing consumption of seafood in the developed world. There is indeed good evidence that fish oils can contribute significantly to our long-term health. On the other hand, of all our foods, fish and sh.e.l.lfish are the source of the broadest range of immediate health hazards, from bacteria and viruses to parasites, pollutants, and strange toxins. Cooks and consumers should be aware of these hazards, and of how to minimize them. The simplest rule is to buy from knowledgeable seafood specialists whose stock turns over quickly, and to cook fish and sh.e.l.lfish promptly and thoroughly. Raw and lightly cooked preparations are delicious but carry the risk of several kinds of food-borne disease. They are best indulged in at established restaurants that have access to the best fish and the expertise to prepare it.

Health Benefits Like meats, fish and sh.e.l.lfish are good sources of protein, the B vitamins, and various minerals. Iodine and calcium are special strengths. Many fish are very lean, and so offer these nutrients along with relatively few calories. But the fat of ocean fish turns out to be especially valuable in its own right. Like other fats that are liquid at room temperature, fish fats are usually referred to as "oils."

The Benefits of Fish Oils As we'll see (p. 189), life in cold water has endowed sea creatures with fats rich in unusual, highly unsaturated As we'll see (p. 189), life in cold water has endowed sea creatures with fats rich in unusual, highly unsaturated omega-3 fatty acids. omega-3 fatty acids. (The name means that the first kink in the long chain of carbon atoms is at the third link from the end; see p. 801.) The human body can't make these fatty acids very efficiently from other fatty acids, so our diet supplies most of them. A growing body of evidence indicates that they happen to have a number of beneficial influences on our metabolism. (The name means that the first kink in the long chain of carbon atoms is at the third link from the end; see p. 801.) The human body can't make these fatty acids very efficiently from other fatty acids, so our diet supplies most of them. A growing body of evidence indicates that they happen to have a number of beneficial influences on our metabolism.

One benefit is quite direct, the others indirect. Omega-3 fatty acids are essential to the development and function of the brain and the retina, and it appears that an abundance in our diet helps ensure the health of the central nervous system in infancy and throughout life. But the body also transforms omega-3 fatty acids into a special set of calming immune-system signals (eicosanoids). The immune system responds to various kinds of injuries by generating an inflammation, which kills cells in the vicinity of the injury in preparation for repairing it. But some inflammations can become self-perpetuating, and do more harm than good: most importantly, they can damage arteries and contribute to heart disease, and they can contribute to the development of some cancers. A diet rich in omega-3 fatty acids helps limit the inflammatory response, and thus lowers the incidence of heart disease and cancer. By reducing the body's readiness to form blood clots, it also lowers the incidence of stroke. And it lowers the artery-damaging form of blood cholesterol.

In sum, it looks as though a moderate and regular consumption of fatty ocean fish is good for us in several ways. Fish obtain their omega-3 fatty acids directly or indirectly from tiny oceanic plants called phytoplankton. Farmed fish generally have lower levels of the omega-3s in their formulated feed, and so less in their meat. Freshwater fish don't have access to the oceanic plankton, and so provide negligible amounts of omega-3s. However, all fish contain low amounts of cholesterol-raising saturated fats, so to the extent that they replace meat in the diet, they lower artery-damaging blood cholesterol and reduce the risk of heart disease.

Health Hazards There are three general kinds of hazardous materials that contaminate fish and sh.e.l.lfish: industrial toxins, biological toxins, and disease-causing microbes and parasites.

Toxic Metals and Pollutants Because rain washes chemical pollution from the air to the ground, and rain and irrigation wash it from the ground, almost every kind of chemical produced on the planet ends up in the rivers and oceans, where they can be acc.u.mulated by fish and sh.e.l.lfish. Of the potentially hazardous substances found in fish, the most significant are heavy metals and organic (carbon-containing) pollutants, preeminently dioxins and polychlorinated biphenyls, or PCBs. The heavy metals, including mercury, lead, cadmium, and copper, interfere with oxygen absorption and the transmission of signals in the nervous system; they're known to cause brain damage in humans. Organic pollutants cause liver damage, cancer, and hormonal disturbances in laboratory animals, and they acc.u.mulate in body fat. Fatty coho salmon and trout in the Great Lakes carry such high levels of these pollutants that government agencies advise against eating them. Because rain washes chemical pollution from the air to the ground, and rain and irrigation wash it from the ground, almost every kind of chemical produced on the planet ends up in the rivers and oceans, where they can be acc.u.mulated by fish and sh.e.l.lfish. Of the potentially hazardous substances found in fish, the most significant are heavy metals and organic (carbon-containing) pollutants, preeminently dioxins and polychlorinated biphenyls, or PCBs. The heavy metals, including mercury, lead, cadmium, and copper, interfere with oxygen absorption and the transmission of signals in the nervous system; they're known to cause brain damage in humans. Organic pollutants cause liver damage, cancer, and hormonal disturbances in laboratory animals, and they acc.u.mulate in body fat. Fatty coho salmon and trout in the Great Lakes carry such high levels of these pollutants that government agencies advise against eating them.

Cooking doesn't eliminate chemical toxins, and there's no direct way for consumers to know whether fish contain unhealthy levels of them. In general, they concentrate in filter-feeding sh.e.l.lfish like oysters, which strain suspended particles from large volumes of water, and in large predatory fish at the top of the food chain, which are long-lived and eat other creatures that acc.u.mulate toxins. In recent years, common ocean fish have been found to contain so much mercury that the U.S. Food and Drug Administration advises children and pregnant women not to eat any swordfish, shark, tilefish, and king mackerel, and to limit their overall fish consumption to 12 ounces/335 grams per week. Even tuna, currently the most popular seafood in the United States after shrimp, may join the list of fish that are best eaten only occasionally. The fish least likely to acc.u.mulate mercury and other toxins are smaller, short-lived fish from the open ocean and from farms with a controlled water supply. They include Pacific salmon and soles, common mackerel, sardines, and farmed trout, striped ba.s.s, catfish, and tilapia. Sport fis.h.i.+ng in freshwater or near large coastal cities is more likely to land an unwholesome catch contaminated by runoff or industrial discharge.

Fat Contents of Common Fish

Low-Fat Fish (0.53%)

Moderately Fatty Fish (37%) Moderately Fatty Fish (37%)

High-Fat Fish (820%) High-Fat Fish (820%)

Cod

Anchovy Anchovy

Arctic char Arctic char

Flounder

Bluefish Bluefish

Carp Carp

Halibut

Catfish Catfish

Chilean sea ba.s.s (Patagonian toothfish) Chilean sea ba.s.s (Patagonian toothfish)

Monkfish

Salmon: pink, coho Salmon: pink, coho

Rockfish

Shark Shark

Eel Eel

Skate