摘录

Chapter One salt-cured foods Our very first impulse is to associate salt and the taste it imparts to a dish. And yet, its presence on the table in a more or less ornate saltcellar in a convivial setting--that of friends sharing a meal and graciously offering one another the spice--is also a legacy from history, one in which the precious spice was at times scarce and expensive. And, in yet a third meaning, salt being given and received is an indicator of the rich social relations by which outsiders integrate themselves into a gathering or, at the very least, are able to strike up an acquaintance.     The chapter thus opens with a Japanese proverb, ushering us from the world of the social contract and aggressive virility to the domestic sphere, in which the cook, whether a man or a woman, prepares dishes.     But why, after all, is salt necessary in food? Because the organism has a daily need for a certain amount of salt (at higher levels, salt becomes toxic). It is even an antiseptic agent: high concentrations of salt kill bacteria. This led to the invention of salt curing, presumably as far back as prehistoric times.     But all such inventions did not occur that early: the salting offish (cod, herring) for the purpose of preservation was invented in historic times, in the fourteenth century, assuredly, for preserving herring. Caviar, one of our luxuries, depends for its preparation on the sturgeon eggs having first been salted. In the nineteenth century, the cossacks of the Don made the preparation of caviar their specialty. An incident recounted in Alexandre Dumas's Russian travel journals hints at an elegant solution to the dilemma of how to reconcile a salt tax levied by a ruler with a communal life in which salt is to some extent demonetarized and in which what enjoys currency is the sharing of salt. This is evoked in a proverb also drawn from a Slavic culture. Salt thus symbolizes social harmony.     Having thus noted the role in food preservation still played today by salt curing, I will move from the larder to the kitchen. In cold dishes, salt is an ingredient essential to the taste of the food it enhances. In hot dishes, its presence in cooking water helps to protect against various denaturations, whether these are an egg bursting, pasta sticking together, or vegetables transformed into a mush not only tasteless but formless as well.     Along the way, I will show how a sauce such as thegarum of Roman antiquity's common people enabled them to defraud the tax system quite as readily as to impart flavor to their dishes and even to prompt other pleasures of the flesh! Like French cuisine, Italian cuisine makes great use of sauces, such as salsa verde, and some Italian proverbs have retained their lewd double meaning, with salted dishes construed as aphrodisiacs.     The salty contrasts with the sweet. The chapter ends with the social solution to this antinomy during the holiday season: it is associated both with the Saint Nicholas figure of northern and eastern countries and with the tradition of giving sweets to children; their shared origin is the salt curing of the pig, sacrificed at Saint Nicholas tide and then macerated all winter long in coarse salt in a salting tub.     But let us first consider the outcome for other foods of being macerated for a time in salt. THE PROVERB OF SALT ON LETTUCE. The Japanese saying "aona ni shio," whose literal sense is "to salt the greens," means the deflating of a braggart. The word aona is a generic term for that which is green, more particularly, for lettuces and vegetables. Shio means salt. Salted lettuce wilts. It tends to shed water through osmosis in an effort to equalize salt concentrations inside and outside the plant cells (a point to which I shall return). The process is unavoidable: As soon as a droplet of water from the lettuce leaf dilutes the added salt, a brine appears. This saline solution is much more highly concentrated than that in the cells of the lettuce leaves. The two saline solutions come into contact on both sides of the cellular membranes that serve as their interfaces. Since these cellular membranes are permeable to water, the internal and external concentrations equalize, as with connected vessels where liquid levels rather quickly become the same.     But the relevant effect is the resulting decayed aspect of the lettuce leaf or, for that matter, any part of a plant. Adding salt ruins freshness, tarnishes, and makes a food less appetizing. Crisp and appealing as it was, it has turned limp and old. The Japanese proverb raises a banal, everyday observation to the symbolic level through a transfer to the moral sphere. The supposedly brave person is so only in appearance; in fact, he or she is a big coward.     Arms and the Man , an 1894 play by George Bernard Shaw, deconstructs heroism and works out in an amusing way this paradox of the warrior, who outwardly appears aggressive, martial, and bellicose yet is in fact timorous and fearful. OSMOSIS AND SALT CURING. Lettuce is not the only organism that wilts in the presence of added salt. To get rid of slugs, one can sprinkle them with salt. They shed their water and die. This results, for the organism as a whole, from osmosis: when water goes back and forth through cell membranes, a dilute solution will mix with a more concentrated solution on both sides of the membrane. After some time, a state of equilibrium prevails in which the concentrations have become equalized on both sides of the membrane. Recall that the concentration is the amount of substance (here, the amount of dissolved salt) per unit volume (see fig. 1).     Osmosis explains quite a few culinary practices. It is one of the reasons for salting the water used to cook an egg: if this salting is not done, the water in the pot can migrate through the porous shell into the egg's interior and dilute its content, which is richer in salt than is the cooking water. The egg would then swell up, causing its shell to burst. Another example, describing a method for treating a vegetable hat closely resembles the one used to destroy slugs, is that of salting cucumbers in order to make them sweat out their water.     Since organisms of all sorts, vegetable and mineral, have an aqueous interior and cells with water-permeable membranes, salt can become toxic once its concentration outside a cell exceeds that in the internal aqueous cellular environment. Thus salt provides humankind with a simple technique for asepsis, as a protection against pathogenic bacteria, a technique that has been used from time immemorial, along with alcohol. On ships, sailors used it, in a painful but effective manner, to disinfect wounds.     Whence, it would appear, the invention of salt curing, from the beginnings of agriculture, impelled by the need to protect various crops from spoiling, that is, from destruction by microbiological infection. As a general rule, salt-curing methods go hand in hand with partial drying techniques, aimed at preserving protein in a more lasting way: milk transformed into cheese, salted fish (most particularly, herring and cod), salted meats (dried meat from Grisons or Italian bresaola , ham, dry sausage, various charcuteries [cooked pork meats]).     The making of ham is an example. It is done in December and January because the hams must be prepared in cold weather (at a temperature below 39.2°F or 4°C) that will last long enough (thirty to forty days, or, to be accurate, two and a half days per half-kilogram) so that they won't spoil before the salt curing can protect them. This period of time explains the connection in Western nations between the Saint Nicholas festival and the period of the year for slaughtering pigs to prepare salted meats, which serve as a repository for protein. I will return to this.     Typically, the processing is done with a mixture of salt, sugar, and saltpeter. Sugar serves to counteract the salt taste and supply energy to the bacteria that transform nitrates into nitrites. Among other functions, saltpeter acts to redden the meat, which would otherwise be a not very appetizing gray color, retard rancidity, and prevent botulinic toxins from developing.     But though the salt curing of a ham occurs because salt protects it from external bacteria, the process also makes use of internal microorganisms: Micrococcus auriantiacus transforms sodium nitrate into sodium nitrite, gluconodeltalactone converts sodium nitrite into nitrous acid, and the ascorbates then free nitric oxide, NO. This reacts with the myoglobin in the meat to produce, in an irreversible process, a compound called nitrosyl hemochrome. If necessary, the salt-curing process is then followed by others, such as those used to make smoked ham. SALTING HERRING. Salt curing ensured the preservation of herring. To do it, one slits the fish with a special knife and removes the gills and the branchia, the heart, and part of the viscera. The blood empties from this wound. Pancreatic enzymes, remaining active in the body of the fish, partly digest its flesh and make it tender. The herrings are then packed together with salt in a barrel (a caque , "cask"--hence the name of the process. [In French, the salt curing of herring is named, following the original Dutch term, "le caquage des harengs," the title for this section of the chapter in the French original.--Trans.]     The procedure appeared early in the fourteenth century (in Flanders circa 1315-1330). A semilegendary character, Willem Beukelsz (or Beukels, Beukelszoon, or William Benkelsoor), is generally credited with its invention. A fisherman or steersman from Biervliet in Zeeland, he died in 1397, if we are to believe a stained-glass window in the church in the town of his birth, which shows him in the process of salting herring. The emperor Charles V visited Biervliet on August 30, 1586, and honored his memory on that occasion. But the very dates of Beukelsz's life are disputed. He allegedly was the deputy magistrate of his village in 1312, but some historians date his discovery to 1384; according to others, who date his death to 1397, the discovery was made in 1349; and according to still others the discovery dates from 1375.     Whatever the historical truth, this astute way of combining salt preservation with the beginnings of a digestion process using proteolytic enzymes was a revolutionary technique. It would be responsible for the prosperity of fishing centers such as Aberdeen; the Shetland Islands, to the north of Scotland; the Hanseatic cities specializing in the twin trades of salt and herring; and the Netherlands especially: according to a proverb, Amsterdam was built on herring casks. THE COSSACKS OF THE DON. Caviar is another salt-cured food. It consists of sturgeon eggs preserved with salt. In the nineteenth century, the cossacks of the Don had a near monopoly on its production, which they used as leverage to exact from the czar noninterference in their traditional way of life. An observation from one of the greatest French writers intrigued me and led me to discover this cunning tactic used by the Cossacks.     Toward the end of his journey to Russia in 1858, Alexandre Dumas again met with those cossacks of the Don who, as he wrote, "gave us such a great fright in our youth" [presumably at the time of the invasion of Paris, after Napoleon's final defeat]. He wonders about their resources: They pay the costs of their upkeep themselves [...] common soldiers receive [...] only thirteen rubles a month. With these thirteen rubles, they must clothe themselves and supply their horse and weapons. [...] They make do as best they can. It is up to them to get through hard times without sin . Russia is indeed the land of impossible arithmetic problems.     Instead of yielding to this absurdity, Dumas would have done better to suspect that he lacked a piece of information. Puzzled by his remark, I was able to find the answer to it in the travel account of the Westphalian baron August von Haxthausen, published in 1847.     The cossacks of the Don lived in a community governed by strict rules, which actually brings to mind the kolkhozes of the post-1917 Communist regime. The cossacks owed military service to the czar, but the wealthiest of them could buy themselves a replacement, which led to some income redistribution among families. However, the central unit of cossack economic life was not the family but the entire community, what one might term the cossack nation. Two chief sources of income prevailed in its budget: the sale of sturgeon-fishing permits and a salt tax (salt was indispensable for curing of the fish and of the fish roe, or caviar). The sale price of a single sturgeon could reach as much as four hundred rubles, the yearly income of the average cossack.     Alexandre Dumas committed two errors, then, errors of ignorance or oversight: the thirteen rubles from the government were in fact just pocket money for a cossack, who lived on the community as a whole rather than at his own family's expense. Moreover, the cossack community--one is tempted to write "the cossack commune"--had plainly negotiated a treaty with the czar to supply him with elite soldiers in exchange for the right to administer salt taxes. The cossacks occupied an area of southern Russia, between the Don and the Volga rivers, a region that, though far from the Caspian sea ("three or four hundred versts away," according to Dumas, or about four hundred kilometers [A verst is a Russian measure of length, 1067 meters or two-thirds of a mile.--Trans.]), nevertheless abounds in salt lakes that, to use Dumas's description, "yield ... fourteen to fifteen million kilograms of salt annually."     Thus, in sharing revenues from such saltworks with the government, the cossacks freed themselves from dependence on the merchants who bought their fish and otherwise might have supplied them with salt at exploitative prices. Moreover, the communal structure of their economic life, strictly egalitarian in a great many respects and ordered by stringent rules, prevented any given family from acquiring a monopoly on the provision of salt.     One can contrast this good fortune of the cossacks of the Don, which they owed to their favorable geographic location next to their own salt supply, with the less bountiful fate of numerous fishing peoples. The cod-fishing people of the Shetland Isles in the north of Scotland were supplied with salt, alcohol, and tobacco by none other than the buyers of their fish, who arrived from the Hanseatic cities of Hamburg, Bremen, and Lübeck. The ensuing near-colonial domination of these buyers would last from the fourteenth century until the beginning of the eighteenth century, well after the decline of the Hanseatic League in the sixteenth century. Finally, the union of England and Scotland in 1707 led to the levying of taxes to dissuade foreigners from trading on British soil. Essentials: scarcity of one commodity (salt) can lead to abundance of another (friendship). THE PROVERB OF FRIENDSHIP OVER SALT. The social importance of the meal, the conviviality that accompanies it, in a warm and friendly atmosphere, have meaning only in an economic context of scarcity, where abundance is something of an exception, where being able to eat one's fill is cause for celebration, where, even if harvests have been good, shortages and famine remain genuine threats. Over the course of centuries, most of humankind has been steeped in such stark tradition.     A Polish proverb says "zjesc z kims beczke soli." Its literal translation is "to have eaten a cask of salt with someone." Thus it carries the meaning of a deep and enduring friendship, one nourished on the relations enjoyed by longtime table companions.     To share bread and salt was and remains the symbolic gesture of hospitality, of the welcome offered a stranger. Familiarity implies the regular repetition of this gesture. Since salt, this costly, indispensable commodity, is nonetheless in the end consumed in substantial amounts--whether a minot , a bushel or, as in this case, a cask or barrel--the fact that one would have shared a great quantity of it comes to signify a lasting friendship.     The fact that volume units rather than weight units are used to measure amounts of salt bought or sold most probably relates to its means of production in the saltworks: salt is gathered, like a grain; it thus admits of the same units of measure, that is, the volume measure of dry granular, or powdery foodstuffs such as wheat, oats, barley, or even lentils. Salt will thus be measured by the muid (cask), feuillette (half-cask), quartaut (quarter-cask), velte, pot, pinte, sétier, demi-sétier, posson , and roquille (one muid is equivalent to 288 pints, or 1,152 sétiers ; the quartaut is one-quarter of a muid ; the velte is 16 sétiers , and the sétier is 4 possons and 16 roquilles ). FOOD PRESERVATION. These ancien régime units of measure have become obsolete. But salt-cured foods are still around. When shopping at the supermarket, we are unlikely to register that we are visiting a museum of technology. But, unlike other sectors of the economy--in sound reproduction, compact discs and DVDs have hardly left any room for LPs and 78s--the food trade is conservative!     To be found side by side on your grocer's shelves are dry sausages and other salt-cured foods whose origin goes back at least to the Middle Ages, canned goods (invented by Nicholas Appert between 1795 and 1810), refrigerated packaged goods (though Romans already used refrigeration, industrial refrigeration was developed during the course of the nineteenth century), pasteurized foods, such as milk, beer, and numerous cheeses (the technique invented by Pasteur dates back to the 1880s), extracts of meat broth (another chemist, Justus von Liebig, reinvented Lavoisier's method of dehydration in the first half of the nineteenth century), dried fruits (dating back to antiquity), frozen or freeze-dried foods (both techniques date from the second half of the twentieth century), condensed milk (invented by Gail Borden in 1856), and more.     All these methods have in common the sterilization of foods (pasteurization) or at the very least the slowing of bacterial proliferation (frozen foods). It is also often important to deactivate certain enzymes, those present in meat, for example. In fact, proteins are the ingredients made inactive by subjecting food to a high or low temperature, by changing the acidity of its surrounding environment (pickles or onions in vinegar), or by salting it. High concentrations of salt (cod or ham) or of sugar (jams) are toxic for many microorganisms.     Spoiled foods can be dangerous because of the multiplication of infectious microorganisms such as E. coli and Clostridium botulinum , which produce highly poisonous toxins. Keeping the temperature low enough (below -25°C) prevents this last bacillus from multiplying and secreting botulin, one of the most toxic substances known.     We owe a certain number of food preservation techniques to the military. In 1795 France, the Directoire--the government at the time--offered a prize to the inventor of an effective method of food preservation. After a good many attempts, Appert recognized that heating must be combined with excluding air from a hermetically sealed container. Napoleon awarded him the prize in 1810 after the French Navy confirmed that Appert's rations survived 130 days at sea without spoiling.     Across the Channel, from 1814 on, the British Army and Navy also supplied their men based overseas with canned goods: in 1810 Peter Durand received a patent from George III for his canning technique, which was developed and marketed by Bryan Donkin and John Hall. (Continues...) Excerpted from salt by PIERRE LASZLO. Copyright (c) 1998 by Hachette Littératures. Translation copyright (c) 2001 Columbia University Press. Excerpted by permission. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.