Who Is Making Us Afraid of Fermented Foods?

A Sourdough Starter That Gets “Angry”

In the spring of 2007, I received a small envelope containing a packet of sourdough starter. This packet had been born on the Oregon Trail, a relic of the era when America’s early pioneers pushed westward. The starter looked unassuming, and I couldn’t help wondering whether I had ordered the wrong thing. Even so, before going to bed, I mixed the starter with flour and spring water and put it into a Mason jar. To my surprise, when I woke up, the sticky, bubbling batter had overflowed the counter. As I cleaned up the mess, I realised that this heirloom sourdough starter was far more lively than shop-bought dry yeast.

This sourdough starter not only has a “personality” but is also very “picky”. If I leave it in the refrigerator for a long time without using it, it gets “angry”. During the months I was on a gluten-free diet, I forced it to ferment rice flour and cassava flour, and it grew even more “angry”; even when I set the thermostat too low in winter, it would “throw a tantrum”. As soon as spring came, it “perked up”. The warm weather made it eagerly digest the organic rye flour I fed it, and it rewarded me with a perfect, crusty French loaf, a warm, tender, supple ciabatta, and a rounded, dense sourdough rye loaf.

The success of this sourdough starter encouraged me to try other fermented products. I looked to Sandor Katz’s The Complete Guide to Fermentation for guidance, and my family of ferments, at various times, has included kefir, kombucha, cucumbers, beetroot and chilli produced by lactic acid fermentation, as well as pulque (a fermented drink popular in Mexico), cider and even red wine.

Every night, I spend time tending my ferments, which helps me feel at peace in this increasingly noisy world. A stable job may collapse along with the financial markets, but I can still look after my ferments. Each is self-contained, and I am rewarded with health and a hobby. George Orwell considered drinking tea the pillar of civilisation. For me, I make tea to brew another batch of kombucha.

I think my motives for starting to experiment with fermentation were not much different from those of other people who keep chickens, make pickles, or similarly pursue “self-sufficiency” in the city. I was trying to establish a longer-term relationship, not just one for the present. For a long time, whether in times of war or peace, plenty or food scarcity, people brewed beer, made cheese, baked bread, and cured meats. It was only recently that the art of fermentation came to be seen as mysterious, even dangerous.

I was advised that home fermentation was a waste of time. I was also warned that I was likely to poison myself. These mildly dismissive and not very credible remarks made me wonder why fermenting at home could not offer the same pleasure of self-sufficiency as making a pie. I set out to find the answer, and the answer is an important chapter in the history of fermented foods. It turns out that suspicion and distrust of fermented foods is a “special product” of the intermingling of scientific and market forces. This “product” is so influential that it has shifted consumer preferences, replacing the richer-flavoured things we can make ourselves with mass-produced items that are bland and unappetising. Fermented foods reflect humanity’s relationship with a second biological realm that is invisible to the naked eye yet ubiquitous. The history of fermented foods is the history of how we came to recognise that bacteria and fungi are both enemies and friends.

Fermented Foods and the Public Health Movement / Sanitary Movement

Eight tourists died at a remote hotel in Loch Maree, Scotland, known for its romantic scenery and excellent management. None of the eight showed signs of weakness or illness. On 14 August, they took part in a hillwalking trip arranged for them by the hotel. That morning, some went fishing and others went hillwalking, before meeting on the shore of nearby Loch Maree for lunch. Their lunch was wild duck pâté, ham and beef-tongue sandwiches, with jam, butter, boiled eggs, scones and cake. Everyone returned to the hotel in time for dinner.

…

The official inquiry began. The hotel’s food was sent for a bacteriological examination, and the chef was questioned. On 30 June, six weeks before the tragedy, one of the best manufacturers in the area had delivered two dozen tins of tinned meat to the hotel. In fact, the manufacturer had observed every precaution at each stage of meat processing. The workers cooked the meat in bulk and completed canning, then placed the unsealed tins in a steamer for sterilisation, and afterwards put it into small glass containers and boiled it a second time. Before the Loch Maree hotel incident, the millions of tins made in this way had not produced a single reported case of poisoning. The chef confirmed that the tins had arrived intact and that, when opened, the contents looked and smelled unspoilt.

There was too little pâté left in the tin to allow a full analysis. But fortunately, the investigators unearthed another important item: a sandwich buried by the boatman in a flower bed. The boatman had saved it from the earlier hillwalking picnic for dinner. He had heard that the duck pâté might be responsible for the recent string of illnesses, and he had buried the sandwich to protect his hens; if they had accidentally eaten it, they could have died. The sandwich was dug up in time, and when it was sent for analysis, the results showed it was contaminated with the toxin — thoroughly contaminated.

This dreadful toxin baffled everyone: it had survived repeated steaming and sterilisation, not to mention burial. In a press release issued on 25 August, the Scottish Health Committee stated that the poisoning was shrouded in mystery but asked the public to remain calm. The investigators successfully isolated a microorganism from the duck pâté. They injected the liquid culture medium into two mice; both mice died, and a rabbit, similarly injected, also died. A bacteriologist pointed out that the rabbit and the mice both showed symptoms of botulism.

The botulinum bacillus is an anaerobic, rod-shaped, spore-forming bacterium that can grow in many places where many other bacteria cannot survive. It secretes a potent biotoxin targeting the peripheral nervous system. This toxin appears only when the bacterium releases its spores. However, these spores are exceptionally hardy: they can survive in many places, from garden soil to the gills of salmon, and withstand extreme cold, high heat and radiation. The first person to identify this botulinum bacillus was the Belgian bacteriologist Emile van Emden. In 1895, while studying a series of poisoning incidents associated with sausages and cured meats, he isolated a microorganism that was not easily eradicated, and which to this day remains the culprit behind fatal foodborne diseases.

An inquest determined that the botulinum bacillus was the only “culprit” in the Loch Maree poisoning incident. This happened to occur in an era when almost every disease was attributed to microorganisms. Through the sanitary movement, microorganisms and how they worked, whether beneficial or harmful, had entered ordinary people’s understanding. The “golden age” of the sanitary movement lasted roughly from the late nineteenth century to the 1930s. It was characterised by a focus on the spread of tuberculosis, typhoid fever and other diseases said to be caused by so-called soil and water contamination. As people gradually came to understand the pathogens behind these diseases, the sanitary movement developed accordingly. Before then, such understanding had been confined to laboratories and factories. Ordinary people rarely knew the biological processes behind the beer they drank, the cheese they ate, or the unappetising meat pâté. Food, prepared in one way, might bring pleasure and health; prepared in another, it might cause illness and death. People may have had some idea of the reasons, knowledge gained from everyday observation. However, these methods were so deeply intertwined with traditional customs that they could not be explained.

The public health movement, the sanitary movement, spread various kinds of knowledge about microorganisms and their effects, and consolidated them in a form almost everyone could understand. Housekeeping books and pamphlets issued by publishers brought “germ theory” into the kitchens of every home as an emerging science, and encouraged housewives to cook in a more hygienic way. Certainly, these were good practices. However, the movement also became a typical, well-meaning “tyranny”, because ordinary household activities took on an atmosphere of invisible danger, aptly captured by the proverb “Small as the viper, it carries venom”.

For centuries, homemade pickles, wine and buttermilk had rarely gone wrong, but now people knew that microorganisms lurked everywhere, invisibly waiting for the slightest slip in cleanliness. Because the risk of microbial contamination was both hard to detect and ever-present, the unease it caused was enough to make housewives choose foods that had once been made at home but were now produced in factories and stocked in shops.

For a time, new methods of fermenting food coexisted with the old ones. Beer bottled by the most advanced modern breweries and factory-produced cheese appeared on shelves alongside homemade pickled cucumbers and bread. But as the wheel of history rolled from the nineteenth century into the twentieth, railways brought new foods to market, and radio broadcasting drew people’s attention to them. The big companies that produced them managed to convince the public that only these foods were reliable, clean and healthy. Following the example of the British Parliament’s 1875 Sale of Food and Drugs Act and 1887 Margarine Act, the United States Congress passed the Pure Food and Drug Act in 1906, further fuelling this persuasive campaign. Only well-capitalised enterprises could invest in equipment that met the new standards, thereby obtaining the government-approved certification that consumers sought. The cost of obtaining that certification became exorbitant, and smaller manufacturers could only watch as their customer base shrank and they soon went bankrupt.

Success made big companies crave more, and they increasingly stressed that they supplied only healthy food. Domino Sugar claimed that machine-processed food was cleaner and therefore safer than food made by hand; Gold Medal Flour boasted that its products had not been touched by any miller; Kellogg’s publicised the fact that its cereal box packaging could prevent contamination; and Heinz invited the public into designated areas of its factory to watch women in clean white uniforms pack the company’s pickles.

Big companies’ advertising campaigns were built on such gimmicks, often escalating from past sensationalism to outright shamelessness. To gain an advantage in the domestic market, the American Sugar Company’s advertisements used magnified images of harmless but frightening microorganisms in brown sugar as evidence that eating raw sugar was dangerous. The campaign was a complete success: even the best-selling Boston Cooking School Cookbook warned readers to avoid brown sugar, because “tiny insects” lurked in it.

The breakfast cereal and biscuit industries also began to follow suit. Manufacturers claimed that only packaged cereal could guarantee freedom from bacteria. Both a meat-and-egg breakfast and yeast-fermented bread could cause illness. And “cornflakes”, produced to the highest standards of hygiene, were so far the safer and healthier choice. For biscuit producers, the “enemy” was an essential fixture of the country shop: the biscuit tin. These biscuit tins, too, were places where bacteria accumulated; wholesale biscuits were poured into tins that might not be hygienic, then picked out by hands that were equally likely to be unclean. Nabisco, by contrast, offered individually wrapped, presentable biscuits that seemed untouched by anyone as the alternative.

For these mass-produced foods, a clean appearance was the sole objective (many large food factories set up mock displays of an ideal production environment for curious visitors, while actual production took place elsewhere, in less tidy places). Beyond that, mass-produced foods were dull, monotonous and uniform, lacking the terroir of traditional foods. “I have heard that American kitchens are dreadful,” Tsar Nicholas II said to one of his subjects, an opera singer who had just returned from a visit to America, “all the food is mass-produced, with no distinctive texture or flavour.”

This assessment applied equally to mass-produced foods in Europe. In industrial cities in Britain such as Manchester, time-pressed workers gave up watercress, fish and other traditional foods and turned to buying tinned beef and Little Bird-brand egg custard, because processed foods were more convenient to eat when they had only a few hours’ spare time. It turned out that the time the workers saved was later lost: their life expectancy was shortened, and many of them became victims of scurvy, tooth decay and other degenerative diseases.

In Switzerland, food industry pioneer Julius Maggi persuaded housewives to accept his improved stock cubes. Although stock cubes lacked the flavour and nutritional value of homemade stock, they still appealed to modern women who worked outside the home. Stock cubes proved a great success, and Maggi founded a company of the same name in Germany in 1897. Convenience triumphed over flavour, and the unbroken, fixed rhythm of factory production gradually reshaped people’s daily habits. Time spent on cooking could not be spent working for money. Moreover, industrial production made food cheaper. Auguste Colte, an industrialist and former chef to Umberto I of Italy, declared in the 1880s: “Every day, the great factories will provide delicious, freshly prepared and cooked food at extremely low prices. This will be the beginning of a new era!”

This was the beginning of a new century. The sanitary movement marked a turning point in food production and storage, for better or worse. It taught ordinary people simple ways to prevent dreadful diseases. Although they became healthier and less prone to illness, they also ceded a great deal of autonomy in household and culinary matters to the government and big business. In the field of human–microorganism relationships, the sanitary movement’s predictions and recommendations were both absolute and monolithic, ignoring individual differences or traditional beliefs.

In traditional thinking, those rather rough, culturally specific guidelines, which inspired creativity in those who followed them, have now been replaced by a strict set of rules based on fear (which is why, today, the knowledge of how to avoid catching a cold is more widespread than the knowledge of how to bake sourdough or pickle carrots). This fear, as the Loch Maree incident showed, is not without reason. Whether bacteria, yeast or mould, these tiny beings, with their dual nature, can bring either illness or health. The contemporary French sociologist Bruno Latour wrote in “The Pasteurisation of France”: “Society is made up not only of people, but of microbes, which intervene and act everywhere.” So who can know the intentions of these “agents” hidden in the shadows?

The Dual Nature of Microorganisms

Before the modern age, no one could have known. To understand the dual nature of microorganisms, we need to know a little about their biological properties. Microorganisms are organisms too small to be seen with the naked eye. In fact, a pinhead can hold millions of microorganisms (or even more). Their existence is ancient. Microorganisms spent hundreds of millions of years waiting for their human foil; once humans disappear, they will probably persist for hundreds of millions of years more. They emerged about 4 billion years ago. Earth at that time was not the friendly, gentle world we call home, but a planet battered by comets, meteors and solar radiation. Besides these impacts, there was the Moon, which orbited much closer to Earth than it does today, its gravity driving violent tides. Beneath the turbulent sea, hydrothermal vents released enormous energy. Around these vents lay deposits of silt rich in substances essential to life. As Wells, the English pioneer of science fiction, wrote, this was “a faint glimmer not yet kindled in the vast void”.

Although not yet kindled, it still existed: life took root in the form of primitive cells. Even as Earth cooled from heat to cold billions of years ago, life continued to multiply and become more diverse. They evolved into two markedly different single-cell forms: bacteria and archaea. Bacteria have cell walls but lack a nuclear structure. Archaea are similar in size to bacteria and likewise simple in structure, but unlike bacteria they have more complex genome structures and metabolic pathways. Although both bacteria and archaea can harness solar energy, the latter prefer hostile environments compared with the former. Apart from these differences, they share some very close relationships.

According to the mainstream endosymbiotic theory, at some point archaea engulfed bacteria without destroying them, and the two fused to form eukaryotes — cells and organisms with a clearly defined nuclear boundary, within which DNA exists in the form of chromosomes (human beings are eukaryotes). Because the bacteria provided extra energy, this new symbiotic form could grow larger, accumulate more genes, and become more complex. The waste product of this evolved strain — oxygen — in turn created the conditions for the diversification of life.

Microorganisms are ubiquitous and play a role in every biological process. They maintain the various ecosystems of the world and contribute to the health of the organisms living in them. They break down dead organisms and aid living ones. However, when conditions are favourable, they can also bring disease, famine and death.

There are about 39 trillion microorganisms living in our bodies, but we understand the roles and responsibilities of only a small fraction of them. We know that many microorganisms can strengthen the immune system, balance blood sugar levels, improve digestion and make other beneficial contributions to our health and well-being. As far as human beings are concerned, we can already control microorganisms to increase our food supply, making food more nutritious and delicious. We have brought about the domestication of microorganisms, just as we brought about the domestication of cattle and sheep, in order to feed ourselves.

However, what are we to microorganisms? This unsettling question still has no answer, and the motives of these invisible life forms remain unclear. In 1891, Professor Percy Frankland observed that they “multiply in great numbers in every environment around us, with extraordinary potential for good and evil; at times they behave like our friends and loyal servants, doing the work they are required to do without complaint, while at other times they resist us like implacable enemies, scorning our strength and ingenuity.” We spend as much energy on fighting those microorganisms that cause disease and death and destroy the fruits of our labour as we do on cultivating those that bring health and happiness. We strive to bring about the domestication of microorganisms so that we do not become their “colonies”.

Happily, as the English novelist Thomas Hardy wrote, these ceaseless struggles have made “very good history”, along with no little delicious food. But before we eat these foods, we should first think about drinks, after all, a considerable number of early fermented products appeared in the form of alcoholic beverages.