HomeBacon & the Art of LivingChapter 13.11: The Salt of the Earth

Chapter 13.11: The Salt of the Earth

Table of Contents

Introduction to Bacon & the Art of Living

The story of bacon is set in the late 1800s and early 1900s when most of the important developments in bacon took place. The plotline takes place in the 2000s with each character referring to a real person and actual events. The theme is a kind of “steampunk” where modern mannerisms, speech, clothes and practices are superimposed on a historical setting. Modern people interact with old historical figures with all the historical and cultural bias that goes with this.

narrative – the history of bacon

The Salt of the Earth

December 1985

Dear Kids,

By December 1892 Minette and I returned to the UK, engaged to be married! You guys made the most amazing arrangements and the day was beyond what words can describe. You made it all possible! The entire visit to South Africa was a highlight. Seeing you guys and of course, spending time with my parents! I had the most amazing time with your grandfather! He is a formidable man. Every interaction we have is precious. It saddens me to see him being unable to do the things he could do just a few years ago. However, his clarity of thought and insight into life became even more poignant. He continued to be intensely interested in my quest. Like he did every time I returned from a trip to the Transvaal, he prompted me to tell him everything, leaving nothing out. He would sit in his lounge chair and listen intently, making careful mental notes on the different points he wanted clarification on.

One afternoon he asked me how I propose one must live when there is so much evil perpetrated on our land against the indigenous people by the culture that I developed such enormous respect for. More than that, he wanted to know how I would respond if war broke out between the Boer republics and England. Of course, I gave him my view which is not important now. It is his comments in response to his own question that I want you guys to take careful note of.

My dad was my best friend. Thank you for visiting him often “It is,” he would often tell me, “what gives the greatest ascent to our self-awareness – precisely the fact that we do not act in brutality or anger or revenge, but that we recognise that life is about more than ourselves. It is our relationship with the collective humanity and the sum total of all of nature that express through us a desire for the good of others!”

These thoughts bring me to the monumental subject of salt which in itself is one of the greatest subjects brought to us by the quest to understand bacon. At the time when I arrived in London, it was the next grans subject on my list to enquire about.

I came across an excellent treatment of salt by Thurmond which I share with you. He writes that “Rock salt occurs as surface deposits in dry salt lakes or as outcrops. In either case, it is almost pure sodium chloride and requires a minimum of processing for use. Evidence suggests that outcrops were first exploited until they were exhausted, and then followed underground (‘following the vein’) just as was done for other minerals. Here, ordinary mining techniques with shafts and galleries were exploited, the supporting pillars of galleries most often nothing but the salt itself left standing during the cutting. When salt banks were too deep or layers too thin to be mined economically, water was conducted to salt layers, the salt transformed to brine and this brine pumped to the surface to be evaporated, usually via artificial heat sources, giving rise to the collections of clay pans, pedestals, and fragments collectively known as briquettage and common in many parts of Celtic Europe. Alternately, veins may descend below the water table, or the water table may rise, as happened most famously at the mines in Hallstatt and Hallein during the ninth century BCE. Fortunately, these deposits were close to enormous reserves of fuel in the form of wood and so artificial evaporation was feasible.”

“In Egypt, in contrast, the hieroglyphic character for salt actually means ‘a specific mineral,’ i.e., a preexisting mineral ready to harvest, ‘salt of the earth.’ It was this last statement that caught my imagination. He continued that the salt was harvested from Wadi Natrun. “The Egyptian priest caste enjoyed a monopoly on trade in this commodity as part of their prebends and therefore propagandized against rival sea salt as filthy and unfit for consumption.”

Tender doc Navy — A tender Document to supply the English navy with salted pork.

By Roman times, many different salts have been identified. I list a few of the main ones: Sea Salt (Sal Marinum) which was harvested from evaporated seawater. This was the most common type of salt. It was used in general cooking, preserving food, and in the salting of fish and meats. Rock Salt (Sal Petrae) was mined from salt deposits and used similarly to sea salt for culinary and preservation purposes. Salarium, often referred to in the context of salary (the allowance given to Roman soldiers for the purchase of salt), this term can also relate to the general use of salt in economic transactions, indicating its value. Alumen, primarily known as an alum (a type of chemical compound) which the Romans used in dyeing and for medicinal purposes. This is not a food-grade salt but still informs us of the broad application of mineral salts in Roman society and then, of course, Nitrum, often confused with modern-day nitrates, nitrum was a type of salt that could refer to several naturally occurring nitrates or carbonate salts. It had uses in medicine, cleaning, and possibly in food preservation as well.

The question came up about how these salts were discovered. How did the ancients distinguish between them? It turns out that the story of salt is in a way, the story of the development of chemistry itself. I have thought a lot about salt in my life and here I want to share the fascinating journey humans had with it and how it shaped our culinary traditions. I insert this letter in my work on bacon curing during my visit to England as it was there, at the Bowood estate in 1892 when I started looking intimately into salt.

Salt – The Oldest and Best Known Preserving Agent

The most magical ingredient in bacon is not nitrate or nitrite but salt by which we mean, of course, sodium chloride! So opens up to us, another vast world. The world of salt. You are by this time well familiar with the book we read in Denmark, Foods by Edward Smith, written in 1867. He writes, “the oldest and best known preserving agent is salt, with or without saltpetre.” (Smith, E, 1867: 34) (1) Remember the quote from the American Encyclopedia of 1858. It said that “Very excellent bacon may be made with common salt alone, provided it is well rubbed in, and changed sufficiently often. Six weeks in moderate weather will be sufficient for the curing of a hog of 12 score.” (Governor Emerson 1858: 1031) (1) As I could have guessed, the story of the use of salt goes back as far as the existence of humanity itself! Before we very specifically get to the glorious subject of sodium chloride, it is time to step back and first look at salt generally again.

Prehistory

“Common salt (sodium chloride) was likely gathered and utilized by one of the earliest Homo species, Homo Habilis, who lived between 1.4 and 2.4 million years ago. (Munas, F.; 2014:213) It is suggested that our nearest extinct relatives, Neanderthals, who existed from about 40,000 to 400,000 years ago, preserved meat by drying. (anthropology.net) This practice could have been discovered from observing leftover meat scraps at sites of kills or slaughters, which freeze-dried or dehydrated, thus lasting longer than the fresh meat removed from the carcass. The use of salt by Neanderthals is speculative, but given Homo Habilis’ potential use of salt and meat drying, it is plausible that Neanderthals also utilized salt. The connection between salt, nutrition, and meat preservation is apparent through simple natural observations. Societies near the sea or salt sources like salt pans or springs would have naturally incorporated salt into their cultural practices.

Evidence indicates that salt was used for preservation well before the last Ice Age, around 12,000 years ago, with salt resources found in Austria, Poland, the Mediterranean, the Dead Sea, and across Europe, Asia, and Africa’s plains. (Bitterman, M, 2010: 16) It appears humanity has always used salt to enhance our diets and likely for meat preservation. The process of adding salt to meat, known as curing, developed into a refined practice from the earliest times.

With the domestication of food sources, including the fig around 9400 BCE, sheep around 8000 BCE, and cattle and pigs around 7000 BCE, human reliance on salt surged for both personal and livestock needs. (Bitterman, M, 2010: 17) Salt became indispensable for curing foods, tanning hides, medicine, and more, underscoring its cultural and survival importance. (Bitterman, M, 2010: 17) “Curing took meat from nature and integrated it into culture,” turning food preservation into an art form that fostered community through culinary delights. (Laszlo, P, 1998: 14)

By 1200 BCE, the Phoenicians traded salted fish in the Eastern Mediterranean, establishing saltworks in their settlements and spreading salt-making technology across the Atlantic to Spain and England, and throughout India, China, Japan, and Africa. (Binkerd, E. F.; Kolari, O. E. 1975: 655–661) Salt’s global significance was evident in its taxation, trade, and use as currency. (Bitterman, M, 2010: 17 – 25)

The Romans, learning from the Greeks around 200 BCE, advanced meat curing methods, including brine pickling, noting saltpetre’s reddening effect on meat—the first record of its colour impact. (Binkerd, E. F.; Kolari, O. E. 1975: 655–661) Marcus Porcius Cato (234–149 BCE), a Roman statesman and farmer, documented precise instructions for dry-curing hams in his work, De Agricultura, offering a glimpse into ancient Roman culinary practices. (economist.com)

Salt’s preservation mechanism stems from its basic composition, initially understood as just common salt and a few others like nitre. (Leicester, H. et al.; 1952: 75) The evolution of food sources, preservation needs, and salt production technology developed in tandem, marking the spread of human culture and civilization.

Salt’s Essential Nature

Humans noticed that not all salts were the same. Simple observation through taste and visual evaluation made us aware of differences in salt from different locations and regions. Some salts seemed to have almost magical properties. We desire to understand these differences that directly lead to the establishment of the science of chemistry. Unravelling the character of salt is one of the greatest stories that exist.

Today we know that salt is formed when an acid and a base are combined through what is called a neutralisation reaction. The crystal or in many cases, polycrystals are ionic compounds, meaning that it is a rigid and regular arrangement of particles of opposing electric charge. The particles are “glued” together by strong ionic or less strong, electrostatic bonds.

This simple explanation did not come easily and unravelling the mystery of the composition of salt took many years and the dedicated work of some of the most brilliant and often, eccentric people who ever walked this earth in modern times. Simple observations of the reaction of different salts in combination with various compounds and understanding their characteristics such as taste was the first step. Soon, though, simple observations were not enough and a comprehensive system had to be built to take the analysis further. It took many years and the labour of many to develop a theoretical understanding of the nature of matter and the forces that hold it together and govern its reactions. Today we know this system as the scientific discipline of “chemistry.” In the process, often, understanding had to wait for the foundations of science itself to be developed before real progress became possible. In the end, incremental as it was and over many generations, insight developed to the point where we could claim a basic understanding of the nature, composition, and function of salts.

Thurmond introduced us to various forms of salts that were known from early on such as sea salt, rock salt, saltpetre, and tartar. Clues to their identification come to us in writings and drawings. Below is the woodcut of the “Man Collecting Tartar From an Empty Wine Barrel”, taken from Ortus Sanitatis, a book published in Strasbourg in 1497. The man is “collecting precipitated solids (potassium hydrogen tartrate) from a wine barrel for use in making potash (potassium carbonate). The solids, known as wine lees, argol or tartar, are formed during wine fermentation. When the argol is heated it forms potash. Potash is used in the manufacture of soap and glass.”

Man collecting tartar from a empty wine barrel

The Principles of Paracelsus

The multi-talented physician, Paracelsus (1493 – 1541), saw salt as one of the three principles namely salt, sulfur, and mercury. This contemporary of Copernicus, Leonardo da Vinci, and Martin Luther, widely regarded as the founder of toxicology, imagined that in every object the principle responsible for its solid state is salt; a second principle (sulfur) is responsible for its inflammability or “fatty” state, and a third (mercury) is responsible for its smoky (vaporous) or fluid state. (www.scs.illinois.edu)

A “fire analysis” was done on a body to isolate the salt. Many cultures, across the world, developed the concept which in the West became popular by the teachings of Empedocle (c. 490 – c. 430 BCE) that all matter comprises earth, air, fire, and water. Earth is the passive element that remains after the fire analysis. By the late 16th and early 17th century, it was realized that the solid which remained after the fire analysis, could further be divided into SALT, which could be removed by diluting it in water and what remained was called EARTH. EARTH was the non-volatile residue left after burning and SALT diluted in water and had a saline taste. While Luther’s reformation gained a foothold in Central Europe and Da Vinci was painting the Last Supper in the Convent of Santa Maria Delle Grazie, in the city of Milan, Paracelsus taught that salt, thus extracted, demonstrated the presence of the universal salt principle and that it was this principle that was behind any body’s solid-state and its resistance to fire. The criteria for SALT being that it is diluted by water and has a saline taste is the reason why liquid acids also came to be known as salts. (Siegfried, R.; 2002: 76, 80, 81)

Johann Glauber

The Bavarian alchemist and chemist, Johann Glauber (1604 – 1670) reported in the mid-1600s on the mutual destruction of acids and alkali’. Hailing from a poor background, he travelled and learned alchemy from various laboratories and teachers. At age 20 he was afflicted with stomach problems, probably after contracting spotted typhus which, for some time after contracting it, causes nausea and vomiting. His travels across Europe brought him to the city of Vienna where the residents recommended that he drink from a local miracle spring which will restore him to health again. Glauber was sceptical about the idea but did it in any event. He drank from the “Hungarian Spring.” (5) His appetite returned and soon he was in good health again. (www.thechemicalengineer.com and Siegfried, R.; 2002: 77)

This unlikely outcome pricked his curiosity. Locals believed the healing power to be due to the presence of saltpetre in the water. He spent the winter, evaporating water from the spring and analyzing the salt. What he found was not saltpetre, but sodium sulfate. (www.thechemicalengineer.com) Sodium sulfate is a mild laxative and he would later market it as Glauber’s salt.

The study of nitre would preoccupy him for years to come, but in his mid-fifties, sodium sulfate would take front and centre stage in his research work. He got carried away a bit when naming it “Sal Mirabilis Glauberi.” He overstated its healing power so dramatically that he received considerable opposition from his contemporaries who regarded him as a dreamer and charlatan. (The Guardian, 1934) An interesting fact to note for our continued interest in the study of saltpetre is the ease with which he was able to test for saltpetre by the mid-1600s. He was able to produce nitric acid (HNO3) by applying sulfuric acid to saltpetre. Later he made potassium carbonate (K2CO3, which is produced by burning saltpetre with charcoal) and nitric acid (HNO3, which they made by distilling saltpetre with fullers earth) from saltpetre and was able to combine these two, potassium carbonate and nitric acid to yield saltpetre, showing his thorough grasp of the acid-base composition of salts. (www.encyclopedia.com) Nitric acid or spirit of niter is a volatile acid and fixed niter (potassium carbonate) is a solid caustic. From this, Glauber concluded that a twofold substance contains both an acid and an alkali.

It was the fact that he could reconstitute saltpetre with fixed potassium carbonate and nitric acid that showed him that saltpetre was not the ultimate universal solvent that alchemists were looking for and that he claimed to have found. It was this disillusionment with niter that caused him to turn his attention back to his Sal Mirabilis Glauberi or sodium sulfate. The formulation of Glauber’s salt is Na₂SO₄·10H₂O.

Glauber’s contribution to the study of salts was considerable. He eventually expanded the list of known salts far beyond common salt and niter. His work on the mutual destruction of acids and alkalis was done with Otto Tachenius. (The Age, 1975) The effervescence that was observed when acids and alkalies were mixed became the standard way of judging the alkali or acid quality of a body. The idea was simple. If a known acid is added to something and it effervesced, the other body is an alkali and vice versa. The early chemists did not see this effervescence as gas being liberated but as some kind of vigorous strife. Acid-base reactions usually produce heat and it is easy to see how the bubbling was seen as “boiling.” (Siegfried, R.; 2002: 76)

Glauber introduced the idea that acids could combine with metals or alkalis to form a salt. The mechanism behind the combinations is seen by him as a certain associative principle which he called “Gemeinschaft.” In his work, he insisted on an accurate description of the technical operation at work. (todayinsci.com) (6)

The Acid-Alkaline Reaction of Salts

The medical chemist, Van Helmont, created a model in the 1600s and he postulated that this acid-alkali reaction is part of animal digestion. One of his students by the name of Sylvius progressed this idea and thought of all bodily functions as acid-alkali reactions and bodily fluids are either acid or alkali. (Siegfried, R.; 2002: 76) Robert Boyle (1627 – 1691) refuted this suggestion by showing some of the many exceptions, yet the reaction between acids and alkali remained “the most familiar among real laboratory material.” By the end of the 1600s, there were three well-known mineral acids, namely, spirit of niter (nitric acid), spirit of salt (hydrochloric acid), and vitriolic acid or spirit of sulphur (sulfuric acid). (Siegfried, R.; 2002: 77)

When exactly the acid-alkali reaction was first studied or who identified it has not been uncovered. It is one of the great untold stories of science. What we know is that during the 1600s, the term alkali was first used in the Arab world and referred to as a vegetable alkali. Books from that time refer to a plant that was called kali and contained potassium carbonate. The ancients obtained it by leaching ashes from the burned remains of the plant. (Siegfried, R.; 2002: 77)

By the 1600s, they recognized another common alkali namely alkali of tartar. This was obtained from the residue in wine barrels and today we know that it was also potassium carbonate. In the early days, they retained the particular name to link it to where it was found. (Siegfried, R.; 2002: 77)

The saturation point of an acid-alkali reaction was believed to be the point where the effervescence stops. At this time, air was not a recognized chemical element and nobody had the idea that the effervescence could be due to the liberation of air. Robert Boyle developed an alternative way to test for acidity or alkalinity and to determine the saturation point of acid-alkali reactions. In his time it was already well known that acids turn green vegetable colour, red. Boyle was probably the first to observe that an alkali would turn the blue to green. It took until 1750 before the use of colours to identify acids and alkalis became commonplace in the scientific community. (Siegfried, R.; 2002: 77)

Neutral Salts

By the beginning of the 1700s, a third class of salts was well established namely neutral salts, containing both acid and alkali. These salts did not effervesce with either acids or alkalies. This category was soon expanded to include the combination of an “acid with earths and metals as well as with alkalies.” (Siegfried, R.; 2002: 77)

Earth is what remains at the end in a distillation vessel and can not be dissolved in water. There has been a debate about whether different earths exist as was the case with different salts and sulfurs (or oils). Scientists were able to, for example, identify a certain kind of earth derived from stones, coral or seashells. It is able to dissolve in acid and when strongly heated, it forms a powdery residue that absorbs water. These were known as absorbent earths. (Heilbron, J. L.; 2003: 226)

The great French chemist, Guillaume- François Rouelle (1703-1770), under whom Lavoisier studied, published some of his most important work between 1744 and 1754 on the subject of salt. At this time, salt was defined as water-soluble, saline-tasting solid. He suggested what is essential, the modern understanding of salt (sel). He was the first to distinguish between acid, neutral, and basic salts. That is anything that would fix the acid into a solid-state whether an alkali, an earth or a metal. (Siegfried, R.; 2002: 79)

Another scientist of this time who devoted much effort to the study of neutral salts was the German scientist, Wilhelm Homberg (1652 – 1713). He spent his adult career in Paris. By the time of his most important work, the following has been established during the previous century. The neutralisation of an acid by an alkali. The mutual destruction of properties. “The available salts were the vitriolic or spirit of sulphur, spirit of niter, spirit of sea salt, and acid of vinegar. The only alkali was salt of tartar (potassium carbonate). ” (Siegfried, R.; 2002: 86)

From the work of Homberg, it is clear the implicit principle behind his experimental work was the conservation of weight. An example is an experiment he did in 1699 where he set out to determine the number of volatile acid salts contained in its solution. “He added acid to weight quantity of alkali until the alkali was saturated, presumably judging that point by the cessation of effervescence. The resultant salt was then dried as thoroughly as possible and weighed. The increase in weight Homburg took to be the weight of the real acid in the solution used. He carried out this procedure using spirit of niter, oil of vitriol, aqua regia, and distilled vinegar, compiling tables of his results. He took no account of the loss of carbon dioxide that escaped from the alkali, of course, for he knew nothing of it.” We see “how futile these attempts were until glasses were recognized as part of chemistry and techniques were developed for measuring and isolating the different kinds of air.” (Siegfried, R.; 2002: 88)

It was about this time when the analysis/synthesis cycle was established as a way to confirm the qualitative composition of a body. If elements obtained from an analysis by fire could be reformed again into the original body, it would prove that the analysis was done correctly and the elements that constitute it, identified. “The permanent secretary of the Academy (of science in France), whose duties included the writing of summaries of the worthy articles in the Mémoires commented that “One is never so sure of having decomposed a mix into its true principles as when with the same principles one can recompose it.” (Siegfried, R.; 2002: 90)

Salts known in the 1700s

Before the 1700s, a scientist could not distinguish between the different alkali metals. Sodium and potassium were often confused. Potassium was produced artificially by slowly pouring water over wood ashes and then drying the crystal deposits. Some of these metals were also found naturally on the edges of dried lake beds and mines and sometimes at the surface of the ground.

Henri-Louis Duhamel (1700 – 1782) realised that certain metals had similar characteristics. He studied samples of salts found in nature and produced by people artificially. This included the study of saltpetre (potassium nitrite), table salt, Glauber’s salt, sea salt, and borax. (Krebs, RE, 2006: 51) He discovered sodium carbonate and hydrochloric acid, a solution with a salty taste, in 1736. (Brian Clegg, rsc, chemistryworld)

Antoine Laurent Lavoisier

It would be the work of Antoine Laurent Lavoisier that finally established chemistry as a science. He did for chemistry, what Newton did for mechanics 100 years earlier. Lavoisier did not discover any new substance, nor did he build any new laboratory- or investigative device. What he brilliantly did was to take the known facts and from these, gleaned the right interpretations. Acids and bases have been examined systematically, chemical substances have been described and characterized, and much work has been done on the relative affinity of bodies for one another.

About saltpetre, Lavoisier concluded that “nitrous and nitric acids are produced from a neutral salt long known in the arts under the name saltpetre.” He explains that this salt is extracted through the process of leaching from the “earth of cellars, stables, or barns, and in general of all inhabited places.” In these places, the reaction of nitric acid takes place with various bases such as lime, magnesia (magnesium oxide; magnesium reacts with nitric acid to give magnesium nitrate and hydrogen gas), potash or argyll. (Lavoisier, A; 1965: 214)

Humphry Davy

Humphry Davy, an eminent English chemist, marked a pivotal moment in the history of chemistry and the understanding of salt when he isolated sodium and potassium in 1807 using a groundbreaking method. Leveraging the technological innovation of his time, specifically the electric battery invented by Alessandro Volta in 1800, Davy applied an electric current through caustic soda (sodium hydroxide) to isolate sodium, and similarly isolated potassium from potash. This process, known as electrolysis, had already been employed to produce chlorine by decomposing sea salt (sodium chloride) with an electric current. By the late 18th century, caustic soda and chlorine found widespread applications; caustic soda was used to process fats into soap, and chlorine was utilized for bleaching fabrics, a technique discovered by Berthollet.

Davy’s experiments led to the identification of “muriate of soda” (what we now recognize as sodium chloride) as being chemically identical to common salt, following his observations of burning sodium in a chlorine-filled vessel. This discovery was profound because it challenged the prevailing chemical understanding of the time. Davy articulated, “Sodium has a much stronger attraction for chlorine than oxygen; and soda or hydrate of soda is decomposed by chlorine, oxygen being expelled from the first, and oxygen and water from the second.” He further explained the attraction of potassium for chlorine as being stronger than that of sodium for chlorine, introducing a method for obtaining sodium by heating common salt with potassium.

Davy proposed a new nomenclature for common salt, based on its composition—indicating it consisted of one part sodium and two parts chlorine, assigning it a chemical representation number of 222. This clarity on the composition of common salt as primarily sodium chloride, established in the early 19th century, opened new pathways for analyzing the nature and effects of sodium chloride and other salts. Understanding the composition of salts dissolved in water, and their interactions with meat and meat-borne microorganisms, became feasible, laying the groundwork for scientific advancements in food preservation.

Davy’s findings underscored that salt, particularly sea salt and salts derived from inland springs and dry beds, contained other metals and compounds, suggesting a complex and consistent nature beyond mere sodium chloride. These discoveries prompted questions about the impact of these additional elements on the curing process of meat. Investigating the role of these elements in salt could potentially enhance the consistency and quality of cured products like bacon, by providing insights into the intricate interactions at play during the curing process.

Humphry Davy’s work not only revolutionized our understanding of elemental chemistry but also had profound implications for the food preservation industry. His isolation of sodium and elucidation of the chemical nature of common salt paved the way for a deeper investigation into the mechanisms of salt curing, influencing practices in the meat industry and beyond. Expanding on Davy’s discoveries involves exploring the specific impacts of various salt compounds on meat preservation, aiming to optimize curing techniques for improved safety, flavour, and texture in cured meats. This line of inquiry is essential for advancing food science and ensuring the continued evolution of meat-curing methodologies. Without it, we can not make any bacon.

Warm greetings, with love!

Your Dad.

Stay in touch

Notes

(1) We have seen how pervasive the occurrence of nitrate is on Earth. One expects to find it in every natural salt spring, salt marsh, dry salt lake and seawater. “Some curing” will take place with almost any natural salt. However, it has been shown that in bacon that was produced with either no nitrites or nitrite levels of 15 ppm, “off-flavours were high and increasing rancidity. A significant reduction in off-flavours in pork during storage was observed when nitrites were added > 50 ppm.” (Rahman, SM, 2007: 307)

Salt springs, analysed in South Africa contained as little as < 1 mg/ L of Nitrate (H)

This does not correlate with the statement by Smith and the American Encyclopedia about the fact that normal salt was equally successful in curing meat.

Adding salt enhances the flavour, but it also accelerates lipid oxidation, even at low levels of addition. Lipid oxidation leads to off-flavour development in meat that does not contain any nitrites. Even a 0.5% addition of sodium chloride significantly increases lipid oxidation when added to restructured pork chops and pork sausage patties following freezer storage. (Pearson, AM, et al, 1997: 269)

(2) ‘The binomial name Homo neanderthalensis – extending the name “Neanderthal man” from the individual type specimen to the entire species – was first proposed by the Anglo-Irish geologist William King in 1864 and this had priority over the proposal put forward in 1866 by Ernst Haeckel, Homo stupidus. The practice of referring to “the Neanderthals” and “a Neanderthal” emerged in the popular literature of the 1920.” (Wikipedia. Neanderthal)

(3). Meat curing can be defined as the addition of salt to meat for the purpose of preservation. (Hui, YH, et al, 2001: 505)

(4) It turns out that “food-grade salt of the highest purity should be used in meat curing practices. Impurities such as metals (copper, iron, and chromium) found in natural salt beds, salt produced from salt springs or sea salt accelerate the development of lipid oxidation and concomitant rancidity in cured meats. Although salt may be of very high purity, it nonetheless contributes to meat lipid oxidation. Nitrite and phosphates, help retard this effect.” (Hui, YH, Wai-Kit Nip, Rogers, R. 2001: 492)

(5) One source says that this took place in Naples and not Vienna. There could have been a spring in Naples, called Hungarian Spring. Drug Discovery: A History by Walter Sneader, 2005, John Wiley and Sons Ltd., p. 64 puts the place where he became ill as Vienna, which fits the Hungarian Spring designation much better.

(6) There is at least one source that puts his invention of Glauber’s salt at 1659. However, from The Renaissance of Science: The Story of the Cell and Biology, by Albert Martini, 2015, Abbott Communications Group, Glauber discovered a simple method of manufacturing hydrochloric acid in 1625 when he was 21. He did this by combining sulfuric acid with table salt (sodium chloride). Sodium sulfate salt was produced by this reaction which is Glauber’s salt, a mild laxative. On the other hand, the 1659 date for the invention of Glauber’s salt may refer to the publication in 1658 of his Tractatus de natura salium. In 1660 a second part was added to the Miraculum mundi. Is is apparently only here when Glauber started to make “sal mirabile” (Glauber’s salt) the main focus of his work, replacing niter. (www.encyclopedia.com).