Chapter 11: From Cooks to Chemists
Tell me what you eat: I will tell you what you are.
-- Brillat Savarin, The Physiology of Taste (1825)
The endless search for the perfect healthy diet continues to dominate Western magazines and television as they churn out "new" information about antioxidants, fat-free diets, high-fiber diets, five fruit and vegetable diets, vegetarianism, and the Mediterranean diet. As a result, many of us are now fairly well versed in the language of nutrients: vitamins, minerals, fats, fibers, and carbohydrates. We may not completely understand what they are, nor exactly how they work, but we are not alone. Chemists, physicians, and dieticians are still exploring the known and researching the new. We have, after all, only tried eating a fraction of the potential edible resources on the planet.
The idea that our food intake can influence our health is a very ancient one, although it was for a long time coupled with the belief that food determined not just health but also social status. Development of medical science and ideas about nutrition were dominated by the teachings of Aristotle, Hippocrates, and, later, the Greek physician Galen, who drew up a dietary "regimen of health" that remained unchanged and unchallenged for centuries. In the second century A.D., Galen declared that an individual's diet should take into consideration their age, sex, "humoral disposition," state of health, and occupation, as well as climatic, seasonal, and environmental factors. It was believed these could have an impact on the individual according to his "qualities" and "humours." For example, small children and the elderly were believed to be full of water and phlegm and should therefore eat "hot" foods. Lamb, which was very moist and "phlegmatic," was therefore unsuitable for old men or babies who already had too much phlegm. By the same principle, a choleric man would need to eat less hot and dry foods, such as cabbage, and more cool foods, such as lettuce. Galen's classification of foods bears little relation to their true nutritional content, whether they are starchy, fatty, acidic, and alkaline foods. But perhaps the most controversial and damaging rule was for fruit, which Galen classified as "cold" and considered a cause of disease. He even claimed that his father lived to be a hundred years old because he never ate fruit.
From what is known today, the Galen diet, if rigidly pursued, could have been nutritionally quite dangerous. Fortunately, few people have ever stuck rigidly to a diet. The rules for the "regimen" were as complex, time-consuming, and detailed as any modern slimming regime. Originally created for wealthy and important members of society, the rules were designed for those who had the time to analyze his or her "qualities" and "humours," as well as the wealth to afford both quantity and choice of foodstuffs. To "eat according to one's qualities" was a maxim that has been practiced by the rich for centuries. While it may have improved their standing among their peers, these diets did little to improve their nutritional health. Yet for hundreds of years, no one dared to question it.
Even more extraordinary were the so-called scientific theories on the natural order of the world that determined a parallel status for foods with those who ate them. Just as they were taught that food consisted of the same elements as themselves, people also believed that plants and animals held a place in the social order. The value of a food could be determined by its place on this ladder of "natural" society. Roots were particularly low in status, since they were buried under the earth. Common greenstuffs that grew at ground level were also thought lowly and fit only for people of low social groups. Leeks, turnips, and onions, along with the common "greens," were left to the lowly peasant to eat. Fruits that grew high in trees and birds that flew in the air were deemed more attractive and beneficial food for the "high born."
The early medieval nobleman in Europe covered his table with huge quantities of food, in particular meat. By the fifteenth and sixteenth centuries, the wealthier classes were less concerned with manly pursuits of hunting and war and were more interested in courtly and diplomatic business. Consequently, they preferred a creative table of quality rather than one overloaded with food. Feasts became an elaborate visual theater and an excitement to the palate rather than a filling of the stomach. Banquets grew more and more inventive in their menus. The ability to serve fresh foods in any season continued to be a great source of social standing. At the same time, expensive, refined foods were considered good for wealthy, refined stomachs, while coarse and common foods were deemed sufficient for the common, poor stomach. An Italian physician predicted sickness for those who ate foods inappropriate to their social status. Rich people, it was argued, should not eat heavy soups made with pulses, vegetables, or offal for they were not "nutritious or easy to digest."
These dietary theories often led people to give up nutritious foods in favor of unsuitable ones. In addition, until the sixteenth century, agricultural practice remained undeveloped and quite primitive, and traditional food-preserving techniques, as well as having practical drawbacks, were not always capable of retaining the vital nutrients in the food. All these factors helped contribute to the widespread dietary diseases that were the scourge of both rich and poor.
Many country people knew enough about their food and about medicinal herbs to counter the worst effects of a poor diet, but as soon as people moved to towns and had less control over their food provision, the problem worsened. The difficulties of bringing large supplies of foods to feed urban workers meant an increasing reliance on preserved and portable foods, and until transport could be improved, urban dwellers, with no kitchen garden or access to country herbs, often ate less well than their rural cousins. The town dwellers lived on bread, pickled or salt herrings, and cheese, with occasional cheap cuts of fresh meat such as sheep's heads or pigs' trotters. When money was short or prices were high, meat had to give place to cheese or broths made with dried peas and beans. Furthermore, urban dwellers who considered themselves to be moving up the ladder were less inclined to eat poor country fare such as vegetables. It was commonly believed that vegetables were "windy" and unfit to be eaten except in broths, or occasionally, well seasoned with oil, in salads. Fresh fruit was sometimes eaten as a dessert by the wealthy, though it was still believed to cause fevers and other ailments.
As a result, scurvy and other scorbutic illnesses were rife, not only on the seas but in the towns as well, particularly in northern climates and among people confined to poor institutions. Hundreds of thousands died from scurvy, and many countless thousands more suffered poor health and low resistance to other diseases because they were in a "scorbutic" state. In 1940 Professor Drummond wrote in The Englishman's Food that children in Scandinavia were found to have mild scurvy at the end of the winter, which rapidly improved as soon as they ate fresh food in the spring. With people subsisting over the intervening centuries on a winter diet of salted meat and pickled fish and rye or wheat bread, scurvy was a common problem across northern Europe, Russia, and even in parts of China. During the 1850s some ten thousand California gold seekers died of scurvy, though many others survived by eating winter purslane known as "miners' lettuce."
Many other dietary diseases were rife. "Night blindness," a common and potentially serious eye condition, was the result of vitamin A deficiency. When the peasant diet was lacking in eggs, milk, animal fats, or green vegetables (usually in the winter months) they were particularly prone to this disease. Cooked liver, if it could be got, was known to provide a quick cure. The fishermen who went on long sea voyages provisioned only with flour, salt meat, and fish often found their sight deteriorating in poor light, their eyelids becoming swollen and sore. Recognizing the early symptoms, they would immediately cook and eat some cod's liver and were soon well again. Xerophthalmia is still found in Egypt, India, Sri Lanka, and in parts of China where a cereal diet dominates and little or no meat or vegetables are eaten. Vitamin A deficiency also causes stones in the bladder, a painful condition that was often described by wealthy gentlemen in their diaries. Perhaps this was partly because the affluent thought that butter, offal, and green vegetables, all rich in vitamins, were foods fit only for the poor.
All over the world these and other dietary deficiencies were affecting both rich and poor who, with no knowledge of vitamins, were unaware of the causes. But they were beginning to discover how to treat them. In the seventeenth century, wealthy households that could afford oranges and lemons added the juice to older, traditional recipes for medicinal syrups made with scurvy grass, brook lime, and watercresses "to make an excellent syrup against the scurvy." As late as the eighteenth century in England people still curdled blue (watered-down) milk with the juice of scurvy grass or some verjuice or cream of tartar to make a concoction "very good to drink in the spring for scurvy." But fruit and vegetables were usually heavily overcooked, reducing their vitamin C content and, as we have seen, many of the traditional preserved foods were failing to provide a whole host of necessary nutrients.
The nineteenth century saw many revolutions, and one of the most significant was in food technology. Cooks and cookbooks, scientists in their laboratories, the poor diet of the sailors, soldiers, and the urban poor, and problems with supplying food to the burgeoning cities all conspired to foster this revolution. Many of the ideas on which it depended were slowly being developed back in the seventeenth century without, however, anyone understanding the underlying principles. Nevertheless, the greatest minds of the age were turned toward improving food preserving and, for a while at least, cooks turned into chemists and chemists into cooks. Eventually in 1861 came the breakthrough discovery of Louis Pasteur that organisms were in the air and were not spontaneously generated. He demonstrated that liquids, especially wine, could be preserved safely by heating in sealed containers to at least 60°C (140°F) and keeping them there for thirty to forty minutes. This procedure, later called "pasteurization," killed any pathogens present and most spoilage organisms as well. In the meantime, however, experimentation continued and empirical knowledge grew. New techniques were tried, but as many were based on incorrect scientific premises, it was to be a long, erratic, and sometimes frustrating journey.
So great a universitie
I think there ne'er was any,
In which you may a scholar be,
For spending of a penny. -- Coffeehouse rhyme, Anonymous (1667)
According to John Aubrey, who briefly recorded many important lives of the seventeenth century, Francis Bacon, philosopher and statesman, would often, for his health, ride out in an open coach in any weather. On one freezing cold, early spring afternoon in 1626, Bacon was out taking the air near Highgate with his companion, Dr. Witherborne. Deep snow still lay along the roadside and "it came into my Lord's thoughts, why flesh might not be preserved in snow, as in Salt." Physician and philosopher both became so excited by the idea that they decided to conduct an experiment at once. "They alighted out of the Coach and went into a poore woman's house at the bottom of Highgate hill, and bought a Hen, and made the woman exenterate it, and then stuffed the body with Snow, and my Lord did help to doe it himselfe." Bacon, by then an infirm old man of sixty-five, became so chilled himself that he was too ill to go home. Dr. Witherborne instead took him to the Highgate home of the earl of Arundel, where Bacon was put into a damp bed. Within three days, he died. It is more likely, however, that it was the damp bed rather than the refrigeration experiment that ended his life.
Bacon was famous for favoring experiment and observation, rather than the old traditions and authorities. His interests were wide and varied and included preserving. Bacon's revolutionary spirit of enquiry and experiment lived on after him, and in the same year that he died, another "philosopher" was born. Robert Boyle, "the father of chemistry," founder of the Royal Society, and still famous for Boyle's Law, was to be the first man to take food preserving out of the kitchen and into the laboratory.
In one generation, in spite of the bloody Thirty Years War and civil war in England, a great era of science, mathematics, and physical experiment had arrived. According to Macaulay in his History of England, Bacon had sown the good seed so that "during a whole generation his philosophy, had, amidst tumult, wars, and proscriptions, been slowly ripening in a few well constituted minds." Men of class, fashion, and learning began meeting in the new coffeehouses opening up all over London, Paris, and Amsterdam in the 1650s. They went daily to their own particular favorite place to gossip and learn the news and to discuss politics, the arts, and philosophies with like-minded peers. Both the English and French authorities feared that these coffeehouses, introduced from the Muslim world, were filled with subversives. They certainly attracted a wide range of custom, providing a unique public place where people could gather without drinking alcohol. In addition, many of the houses provided special rooms for social or business meetings.
The young Robert Boyle, who had grown up during these exciting times, was already in touch with a circle of natural philosophers that became known as the "invisible college." These men, dedicated to new scientific enquiry and practical experiment, met regularly in coffeehouses, where they debated a wide and eclectic range of scientific ideas covering everything from mathematics to agriculture. Congregating every Wednesday or Thursday afternoon in Garraway's or Jonathon's coffeehouse in Cornhill, early members included John Aubrey; John Evelyn, botanist and numismatist; Samuel Pepys; John Locke; the statistician Sir William Petty; John Dryden; Sir Christopher Wren; Sir Kenelm Digby, Roman Catholic writer on recipes and domestic economy; Robert Hooke, mathematician and physicist; and Jonathan Goddard, one of the first English makers of telescopes.
But anyone who had paid a penny could sit by the fire and smoke as he listened or joined in debate with these able and inventive men whose insatiable appetite for knowledge was further fired by ideas flowing across the Channel from Europe. They even managed to conduct some experiments as they gathered around the warm fire and peered through the smoke into a homemade microscope or at some strange liquid in a bottle. Robert Hooke recorded in his diary: "Met with Metredony Speed. At Garaways with hime and discourses of wine and fermentation etc." On another occasion he observed "a hair worm and some miscroscopes shewd at Jonathans." Women were occasionally tolerated as spectators. Pepys describes, with some reluctance, a visit by the duchess of Newcastle: "Several fine experiments were shown her of Colours, Loadstones, Miscroscope, and of liquors; among others, of one that did while she was there turn a piece of roasted mutton into pure blood."
Gatherings also took place at Gresham College, and it was at one meeting there in 1660, when Sir Christopher Wren gave a lecture, that an idea for a permanent institution to promote experiments in physics and mathematics was raised. After the restoration of Charles II, the Royal Society received its royal charter. Its motto was taken from Horace: "The words are the words of a master, but we are not forced to swear by them. Instead we are to be borne wherever experiment drives us." This showed a clear determination to move on from the rigid laws laid down by the early classicists Aristotle, Galen, and Hippocrates. Meanwhile, a similar movement was growing in Paris, where the Acadamie des Sciences was founded in 1666.
But the informal nature of the early days of the "invisible college" remained unchanged. Essays, questionnaires, and letters continued to be circulated and shared among both the London members and those on their country estates far from the city. A small number of aristocrats and gentry, obliged to stay on their estates during the Civil War and the interregnum, had found time on their hands and begun to experiment with improving the fertility of their land, their crop yields, their livestock breeding, and the traditional ways of preserving their estate produce. These men corresponded with each other, sharing ideas and the results of their investigations. Sometimes, however, there seems to have been some rivalry and secrecy concerning discoveries. Robert Boyle records that he has heard from "an eminent Naturalist, a Friend of yours and mine, that hath a strange way of preserving Fruits, whereby even Goos-berries have been kept for many Moneths, without the addition of Sugar, Salt, or other tangible Bodies; but all that I dare tell you, is, that he assures me his Secret consists in a new and artificiall way of keeping them from the Air."
There may well have been an element of personal rivalry as well, as the possibility of financial reward beckoned. John Aubrey writes that Boyle "is charitable to ingeniose men that are in want, and foreigne Chymists have had large proofe of his bountie, for he will not spare for cost to get any rare Secret." In fact Robert Boyle was busy experimenting and investigating a wide range of ideas, in particular the activity of gases and air, and it was this interest that first led him to experiment with new methods of preserving food. Boyle, like so many others until Pasteur's breakthrough, at first believed that air alone was the cause of putrefaction and that the ability to remove it from the food was the answer to successful preserving. He would have been aware that keeping food free from air was not a new idea and that people had been attempting to achieve it with varying success for centuries. More recently, the bottling of fruit and potting of cooked meats and fish had been creating considerable interest as new ways of preserving fresh meats and fruits "beyond their wonted seasons of duration."
But it may also be reasonable to assume that another reason that Robert Boyle and some of his colleagues spent so much time and energy on experimenting with ways to preserve food "without the addition of Sugar, Salt, or other tangible Bodies" was more than simply academic. Fellow Royal Society member Samuel Pepys was for a time responsible for naval food supplies. He no doubt would have voiced the Admiralty's wish to find new ways to feed its men in the light of the then commonly held belief that salt meat caused scurvy. This was coupled with the recent challenge that fruit, which might offer an effective cure, had somehow also to be preserved for long voyages. The most effective methods known then involved sugar, which was expensive, and as Boyle himself noted, too much sugar "clogs most men's stomachs."
Over half a century earlier, Sir Hugh Plat had tried unsuccessfully to interest the Admiralty in his many revolutionary preserving ideas, knowing that a contract would bring him considerable reward: "But if I may bee allowed to carrie either roasted or sodden flesh to sea, then I dare adventure my poore credit therein to preserve for sixe whole monethes together; either Beefe, Mutton, Capons, Rabbits, etc. both in a cheape manner, and also as fresh as we doe now usuallie eat them at our Table. And this I hold to be a most singular and necessarie secret for all our English Navie; which at all times upon reasonable tearmes I will be readie to disclose for the good of my country." Boyle, too, was keenly aware of the importance of his work to seamen. He wrote, "tis sufficiently known to Navigators, how frequently, in long Voyages, the Scurvy, and other diseases, are contracted by the want of fresh Meat, and the necessity of feeding constantly upon none but strongly poudred Flesh, or salted Fish; and therefore, he is much to be commended that hath first devised the way to keep Flesh sweet, without the help of those fretting Salts." Boyle conducted a number of experiments including preserving meat in alcohols, thereby keeping "an entire Puppy of pretty bigness, untainted for many weeks" and preserving other foods with mixes of chemicals such as saltpeter, lime water, and even urine. He also experimented with sealing fruit in airtight bottles without adding sugar and potting cooked meats under an airtight layer of fat, both ideas, as we have seen, that were already beginning to appear in contemporary cookery books. Boyle, however, was keen to take these processes further, in particular to find ways to preserve "raw flesh itself...with things that do not so much fret it, nor give it so corrosive a quality, when eaten, as our common Salt doth." Much of the food being sealed into containers retained some air, unwittingly sealing the problem in. Boyle tried removing all the air by creating a mechanical vacuum pump to draw out any remaining or trapped air, and he invented a manometer with which to measure air pressure. In 1667 he wrote: "I have also lately put into practice another thing, about which I must earnestly desire your secrecy....The thing I pretend to do, in short is this; to seal up glasses hermetically, when without the help of heat (for it is done by the engine) they are more exhausted of air."
Boyle still favored the exclusion of air over the use of heat. However, a number of experiments over succeeding years gave varying degrees of success, and these results clearly showed him that while air had a role in food spoilage and removing it helped the preservation, it was not the whole cause of spoilage nor the complete answer to preserving. He also experimented with using steam to create a vacuum in food containers, which often brought him close to realizing the importance of the use of heat in preserving. Boyle worked closely with Samuel Hartlib, who had been the focus of a large part of this group actively trying, among many other experimental activities, to improve food production and preservation, and with Robert Hooke and Antony van Leeuwenhoek, who both developed simple microscopes revealing minute creatures and "animalcules," blood corpuscles, and milk-fat globules. Boyle also conducted experiments with another colleague, French physicist Denys Papin, who had taken refuge in England to escape religious persecution and is still famous for his "Digester of Bones." The forerunner of the modern pressure cooker, Papin's contraption boiled bones down to a gelatin in which food could be preserved. Papin later took over many of Boyle's experiments with food and, using his "digester," began to heat food such as gooseberries in airtight containers. At last he reached the critical breakthrough that had eluded Boyle: "Heating under vacuo doth hinder them from fermenting." But the heat process Papin used was very mild; it involved putting glass containers of fruit in cold water in a bain-marie and bringing the water to the boil, a process that seemed to preserve without using sugar for some acidic fruits, but was not effective for raw meat. From this Papin did come to another important conclusion, that different foods reacted in different ways and might require different treatment or degrees of treatment for successful preserving.
Papin's huge digester could cook up to ten pounds of meat and he experimented with cooking meat jellies, which he believed could solve the pressing problem of scurvy. However, like portable soup and potted foods, meat jellies were expensive and difficult to make in any quantity, and none was ever made for use at sea. Papin continued to work closely with Boyle and members of the Royal Society, reporting back regularly on his findings, successes, and failures, which the eminent men were required to taste and possibly even to risk some upset stomachs. In 1687 Papin produced some peas that he had preserved in vacuo ten months previously; "I have put some butter, pepper and salt to season part of them, that the Royal Society may be pleased to try how they will taste." In the minutes of the meeting it was observed that the peas had "contracted something of a rancid Tast, but were otherwise well preserved," and in 1687, the society reported that Papin had succeeded in preserving "great quantities of Fruit with their Tast without any sugar or other alteration than what can be made with a little boiling."
The Way is this; he shuts up the Fruits in Glass Vessels exhausted of the Air, and then puts the Vessel thus exhausted in hot Water, and lets it stand there for some while; and that is enough to keep the Fruit from the Fermentation, which would otherwise undoubtedly happen.
This description, which involved heating food in sealed containers, might sound familiar to anyone used to bottling fruit or vegetables. In fact, it came tantalizingly close to the method finally developed for canning one hundred years later.
In 1691 Robert Boyle died, Denys Papin had moved abroad, and Thomas Porter and John White were granted a patent for "Preserving all Kinds of Foods." Neither man was a member of the Royal Society, and there is no record of their preserving method, but it was significantly the first commercial patent for food preserving and shows that there was by then considerable interest in developing and marketing new kinds of processed foods for sale. By now both the French and British navies had been receiving a steady stream of submissions for new food-preserving processes from enthusiastic inventors. They were sent a strange assortment of pots of meat, dried cakes of soup, purées and concentrates, dried vegetables and pastes, and new types of biscuit. Only a few of the ideas proffered were given sea trials. None, so far, was considered better or cheaper than salt meat and hardtack.
But then, in the wake of the French Revolution of 1789, the French government offered a reward to anyone who could develop a new method of preserving food. The stipulation was that the end product should be easily transportable, economic to produce, and provide a better diet than salt meat. It was this French initiative that found the man who produced the solution.
Copyright © 2000 by Sue Shephard