Introduction to Bacon & the Art of Living
The quest to understand how great bacon is made takes me around the world and through epic adventures. I tell the story by changing the setting from the 2000s to the late 1800s when much of the technology behind bacon curing was unraveled. I weave into the mix beautiful stories of Cape Town and use mostly my family as the other characters besides me and Oscar and Uncle Jeppe from Denmark, a good friend and someone to whom I owe much gratitude! A man who knows bacon! Most other characters have a real basis in history and I describe actual events and personal experiences set in a different historical context.
The cast I use to mould the story into is letters I wrote home during my travels.
Dublin and the Injection of Meat
When I wrote to you the last time Minette and I were on a steamboat on our way to London. From there we took the train to Calne. John Harris arranged the most amazing welcome for us at his house with many of the staff from C & T Harris in attendance. He suggested that since I have an interest in discovering the origins of meat curing in order to understand how excellent bacon is made, we take a trip to Ireland and visit the University of Dublin.
That was to us, a most excellent suggestion. In Dublin, we were met by Dr. Stamatis Papaikonomou (1) who lived in Johannesburg for a time. He knows John Harris on account of Dr. Stamatis taking care of a recurring eye infection. Dr. Stamatis very graciously agreed to show me the old medical faculty where there is an old professor teaching physiology who will be able to enlighten us as to the origin of meat injection.
Meat Injection Started in Cadavers
We learned that the practice of injecting meat with brine started as a way to preserve cadavers. That preserving human corpses for medical studies was something that made complete sense to me. Many years ago, as a boy, I read how Von Hombult and Guthrie went from house to house after a particularly heavy thunderstorm buying up the copses of the deceased for their own medical studies. Before the age of refrigeration, preserving human remains in order to study the make-up of the human body would have received considerable attention.
Leonardo Da Vinci
Leonardo da Vince (1452–1519) described a method of preserving the cadavers for his own dissection and study. (Brenner, E.; 2014) The mixture he used consisted of turpentine, camphor (scent masking), oil of lavender (scent masking), vermilion (colouring agent), wine, rosin (a resin used as an adhesive), sodium nitrate, and potassium nitrate. In his mix, for preservation, he relied on sodium and potassium nitrate and turpentine. The man who took front and center stage in the development and spread of the practice was a man we already met with the surname of Morgan.
It was a certain Mr. Morgan, in England, who invented the technique of injecting a liquid brine into the meat in the first place. The motivation was to increase the rate of curing by getting the brine faster into the meat in order to reduce the time required for processing. In temperatures above 20 deg C, pork spoils in three days.
By injecting a liquid brine into the meat at evenly spaced intervals, the brine diffuse quicker through the meat. Morgan’s interest was the preserving of meat generally but included meat preservation for long sea voyages before the advent of refrigeration and not the curing of meat by farmers.
Edward Smith whos book, Foods, (1873) we read and discussed in great detail in Denmark wrote that “Mr. Morgan devised an ingenious process by which the preserving material, composed of water, saltpeter, and salt, with or without flavouring matter, was distributed throughout the animal, and the tissue permeated and charged. His method was exemplified by him at a meeting of the Society of Arts, on April 13, 1854, when I [Edward] presided.” (Smith, E, 1873: 35)
He describes how an animal is killed in the usual way, the chest opened and a metal pipe connected to the arterial system. Brine was pumped through gravity feed throughout the animal. Approximately 6 gallons were flushed through the system. Pressure was created to ensure that it was flushed into the small capillaries. Smith reported overall good results from the process with a few exceptions. He himself seemed unconvinced.
An article appeared in the Sydney Morning Herald that mentions Dr. Morgan and his arterial injection method. An important observation from the article is the date of 1870. By this date, he is referred to as “Dr. Morgan”, cluing us in about the timeline of Morgan’s life.
A second observation is a drawback of the system. The article states that “salting is the most common and best-known process of preservation (of meat), the principal modern novelty being Dr. Morgan’s plan of injecting the saline solution into the arterial system – the principal objection to which has been that the meat so treated has been over-salted.” (Sydney Morning Herald, 1 March 1870, p 4)
The brine mix that Mr. Morgan suggested was 1 gallon of brine, ¼ to ½ lb. of sugar, ½ oz. of monophosphoric acid, a little spice and sauce to each cwt of meat. (Smith, E, 1873: 36)
Seventeen years after Smith met Morgan at the Society of Arts meeting, in 1871, Yeats reports on a certain “Professor Morgan in Dublin, proposed a method of preservation by injecting into the animal as soon as it is killed, a fluid preparation, consisting, to every hundredweight of meat, of one gallon of brine, half a pound of saltpeter, two pounds of sugar, half an ounce of monophosphoric acid, and a small quantity of spice.” (Yeats, J, 1871: 225)
The plan was widely tested at several factories in South America and by the Admiralty, who had reported that they had good results from the technique. (Yeats, J, 1871: 225, 226) It was in all likelihood the same Morgan that Smith reports on who, by 1871, became a professor in Dublin. One interpretation of the Yeats report is that Morgan, by this time, abandoned his arterial injection method for a more general injection into the muscle. It is more probable that Yeats simply is not concerned with a detailed process description.
Notice, as a matter of interest that he used the same basic brine mix of salt, water, saltpeter, sugar, monophosphoric acid and spices. This, together with the similarity in surname makes it quite certain that Mr. Morgan and Prof. Morgan are the same person. In itself, this is an example of perseverance! In 1854 his arterial injection was met with skepticism where Yeats reports in 1871 that the Admiralty viewed his improved method.
Was this Morgan’s Invention?
The concept of arterial injection was not new. By the time Morgan demonstrated it to the Society of Arts, on April 13, 1854, it may have been as old as 150 years, used for embalming corpses for the purpose of medical studies. This invention is credited by some to the Dutch physician, Frederik Ruysch (1638 – 1730). He injected a preservative chemical solution, liquor balsamicum, into the blood vessels, but his technique was unknown for a long time. (Bremmer, E.; 2014)
British scientists who used arterial injection and from whom Morgan could have learned the system were the Hunter brothers William (1718–1783) and John (1728–1793) and their nephew, Matthew Baillie (1761–1823). The injection was into the femoral arteries. They all injected different oils, mainly oil of turpentine, to which they added Venice turpentine, oil of chamomile, and oil of lavender. Vermillion was used as a dye to create a more life-like skin colour, but would also have added preservation to the final solution. (Bremmer, E.; 2014)
There is a reference from 1837, on an essay delivered on the operation of poisonous agents upon the living body by Mr. John Morgan (1797 – 1847), F.L.S Surgeon to Guy’s Hospital. (1837; Works on Medicine) The same publication contains an article by Dr. Baillie, M.D. on the morbid anatomy of some of the most important parts of the human body. John Morgan was definitely well familiar with arterial injection. Not only due to the fact that he was a contemporary of Baillie, but demonstrator of anatomy at the private school near Guy’s Hospital. (livesonline.rcseng.ac.uk/)
Despite the fact that our professor at the University of Dublin can not locate a single reference, it is very likely that he was the father of Dr. John Morgan (Circa 1863), a professor of anatomy at the University of Dublin. A process of arterial injection is described that was used by Dr. John Morgan from the University of Dublin. ” John Morgan, a professor of anatomy at the University of Dublin in Ireland, formally established two principles for producing the best embalming results: injection of the solution into the largest artery possible and use of pressure to push the solution through the blood vessels. He also was among the first to make use of a preinjection solution as well as a controlled drainage technique. Morgan’s method required that the body be opened so the heart was visible, then an 8-inch pipe was inserted into the left ventricle or aorta. The pipe was connected to yards of tubing ending in a fluid container hung above the corpse. The force of gravity acting on the liquid above the body would exert about 5 pounds of pressure, adequate to the purpose of permeating the body.” (Wohl, V.) This process described here is applied, not to the preservation of animal carcass, but for embalming a human body! It is, however, the exact same process that he demonstrated years earlier in London to Smith at the Society of the Arts meeting on 13 April related to carcass preservation.
From the process description, it is clear that we have finally identified the Morgan, father of the arterial injection method in meat curing as Dr. John Morgan, professor of anatomy at the University of Dublin, son of Dr. John Morgan, Surgeon to Guy’s Hospital. The original inventor of the system was the Dutch physician, Frederik Ruysch and the application was embalming.
With all the information fresh in our memories and my ever-present notebook tucked under my arm, Dr. Stamatis suggested that we go to a pub down the road for a drink. Dr. Stamatis did some reading on the subject before we arrived.
Mr. Davis from Adelaide: The Australian Agent of Dr. Morgan
Dr. Stamatis came across an 1866 article in the Launceston Examiner where it is reported that Mr. Davis, from Adelaide, bought the patent from Dr. Morgan. Mr. Davis took up “premises at Town Marie, on the Bremer River, about six miles from Ipswich” and the operation of curing commenced.
The process is described as follows. Dr. Morgan’s patent consists of emptying and washing out all, even the minutest blood vessels of an animal, while the carcass is still warm, and afterward, filling the same with brine. “This is done in a very simple and expeditious manner, and the meat thus cured is very different indeed in flavour, consistency, and general appearance, from that which has undergone the old and more tedious process of salting.” (Launceston Examiner, Sat 17 Mar 1866, Page 2, CURING MEAT BY DR. MORGANS’ PATENT PROCESS)
The journalist reports that he saw “five beasts killed and cured in about an hour at Mr. Davis’s establishment. Having been despatched in an ordinary way, the animals are laid on their backs, sometimes before they are quite dead, and the flesh having been laid open with a knife on the breast bone, the bone is sawn in two, longitudinally, and forced open with an iron screw until the aperture assumes an oval shape, about twenty inches long by seven or eight wide.
The operator, who is Mr. Davis’s manager, Mr. Bennett (the only person, we believe, in the colony, besides the patentee, who is practically acquainted with the process) then commences his manipulations with the animal’s heart, to which he obtains access by means of the opening we have described. It isn’t impossible to see exactly what Mr. Bennett is doing as his hands are inside the body of the beast and his face is close to the opening. It is understood, of course, that he is making an incision in the great artery of the heart, and fastening, in the hole thus made, the copper nozzle of a long gutta-percha tube (which descends from a bucket suspended from the ridge pole of the roof), containing the wash. Having secured this firmly in the aorta, trying it around the neck with twine so as to prevent any escape, he next makes another opening at a short distance from the first, and turning the stopcock at the end of the gutta-percha tube, the wash, which is a diluted brine, is forced by gravitation into the aorta, driving before it the blood which escapes from the other opening in a rushing stream, rising several feet into the air.
About a minute suffices to drive out all the blood, but the injection is continued some time longer, so as thoroughly to wash out the blood vessels until at last the wash comes away almost in a pure state. The beast is then rolled over so as to allow all the liquor to drain out, the carcass being afterward restored to its previous position. When this has been done, the operator closes the aperture which he had made to enable the blood and wash to escape and having unscrewed the gutta-percha tube, screws on a second precisely similar to the first, but which is attached to the bottom of another bucket which contains the brine.
This brine is composed simply of salt, saltpeter, and sugar but Mr. Davis proposes to add a little spice to the solution, as an experiment, to improve the flavour of the meat. The tube having been fixed, the tap is turned, and the brine is thus forced into the veins and arteries. In order to make quite sure that the liquor has thoroughly permeated every portion of the carcass, a small scratch is made near the end of the tail and a fountain of brine immediately jets out. A scratch on the thick leathery cuticle of the nose is attended with a similar result. (We may mention also that even the hides are thoroughly cured by the one process, and when taken off, the carcasses are immediately stacked. One of the animals, too, that we saw cured was a cow heavy in calf and when the young one was taken out, it was found to be thoroughly impregnated with the brine).
We have eaten the tongue of the beast cured in this manner, and nothing could have been nicer, or more thoroughly preserved; the beef, too, as we know by experience, will bear roasting – an operation which would not add to the succulent of ordinary salt meat. The blend vessels having been thoroughly filled with brine, the carcass is left to soak for half an hour or more. It is then strung up and dealt with in the ordinary manner; the pieces are thrown into brine for a short time, turned over from time to time, and thoroughly examined, and, being found perfectly sweet, are placed in casks ready for shipment.
Mr. Davis has commenced operations at a very unfavourable period of the year, and the only premises which he has been able to obtain are not the most suitable for the purpose. He has had to dress meat with the thermometer at 104° in the curing shed, and it is therefore not surprising that, in one or two exceptional cases, his success should not have been quite perfect. The test to which the meat is subjected, however, is so thorough that there is not the smallest chance of its being shipped in an unsound state. Mr. Davis lately shipped nearly a hundred casks (3041b each) to, Sydney, for transmission to England by the Orwell.
It was stated by a Brisbane contemporary that 2c per pound was expected to be reached in the London market. This is absurd; anything over 6d will pay Mr. Davis well, and 9d or 10d is the outside contemplated. We shall be glad to hear that something like this has been obtained and that this new and valuable industry is, therefore, likely to be established as a permanent addition to the resources and wealth of this town and district.” (Launceston Examiner, Sat 17 Mar 1866, Page 2, CURING MEAT BY DR. MORGANS’ PATENT PROCESS)
Benefits of Arterial Injection
A most interesting coincidence occurred. Minette, Dr. Stamatis and I were still in the pub close to the University when a man, visiting the university from the country of New Zealand commented on our discussion. He first apologised for listening to our conversation and introduced himself as Stuart Merrylees. It turns out that Stuart is also in the pork industry, managing production for the largest Bacon producer in New Zealand. He suggested that he “did some trials called pegging the jugular vein in and the jugular vein out. Once the liquid flows clear, peg the outgoing vein and stop the pump to the ingoing vein and tie it down. One should use about 30L of product to be successful.”
He mentioned that some butchers claim that this operation makes the meat more tender. I wondered what the benefits would be and why the meat will be more tender. A clue to understanding some of the chemistry at work is to remember that manipulation happens while the carcass is still hot. This changes the rules dramatically. Note the actual wording from the journalist, describing the Davis operation, “The animals are laid on their backs, sometimes before they are quite dead.” Why would this make the meat more tender? The one reason would be if there is an absence or resolution of shortening.
There are several techniques to prevent shortening. One notable example presents itself, again from our evening of oyster eating in Stellenbosch. My one Kiwi friend is a keen hunter and in the same discussion as we had about the arterial injection, mentioned how he keeps a deer carcass at chilled temperature and ages it for a set time which he measures by the age-old method of pulling on the tail of the dead animal. If the tail comes loose, he knows it has been long enough. This turns out to be an ancient invention where conditioning and aging are used to prevent cold shortening in New Zealand lamb. “This method calls for holding the carcass in a conditioning-aging room until they have gone into rigor mortis. The temperature and time specifications were developed for the industry with the time-varying with the temperature, that is, longer times were required at lower temperatures. The conditioning and aging will thus prevent cold shortening and the accompanying cold-induced toughness.” (Pearson, A. M.; 1989 : 415) This is however not what happens in arterial injection. It is nevertheless fascinating that the technique for preventing shortening in cold environments and arterial injection was discussed in sequence – both very typical for that part of the world.
Two factors would counteract the onset of shortening namely a higher pH and higher ATP levels. The table salt (NaCl), saltpeter (KNO2) and sugar added by Davis will not have any effect on the pH and will therefore not impact the meat toughness or tenderness. The monophosphoric acid in Morgan’s brine formulation may, however, have the effect of lowering the pH.
In general, the normal pH of the muscle in an animal when alive is 7.0. After rigor, the pH drops to around 5.5. “The increased acidity of post-mortem muscle results from the accumulation of lactic acid, which is formed as glycogen is degraded (anaerobic glycolysis) to produce ATP. Animals that are not handled optimally ante-mortem will likely have faster running muscle biochemistry and a more rapid decline in muscle pH. This change in pH during the conversion of muscle to meat is perhaps the most important event because it affects so many chemical, physical, and sensory traits of meat products.” What you want to prevent is rapidly dropping pH while the meat is still warm. Muscle pH is critically important because both the rate and extent of pH decline greatly affect meat properties. If the pH decline is rapid and reaches 5.5 to 5.8 while the muscle temperature is still high (more than 36 °C), the meat may become PSE.
Using the arterial system, and assuming the water is between 20 and 25 deg C, the fact that water is administered while blood is in the carcass should aid in a cooling down of the carcass, but not to levels that are too low. This should have a positive effect on meat quality.
Let us consider the relationship between the levels of ATP and rigor. Rigor does not occur until approximately one-half of the ATP is depleted. (Pearson, A. M.; 1989 : 410) The arterial injection of brine should have no impact on the formation or depletion rate of ATP. Dr. Francois Melette explains that ATP consumption is at this point only and anaerobic release of energy. The muscle “does not know” that the blood is being drained and it enters an anaerobic metabolism as if the animal is being chased. The anaerobic regeneration of ATP is very ineffective and the glucose molecules are rapidly converted to lactic acid which accumulates in the absence of blood flow. (Private communication with Dr. Melette)
He doubts if the lactic acid that is now being washed through the system will have a material effect on the meat fibers and will in all likelihood have no tenderising effect. The benefit is, according to him, more likely in the rapid decline of pH which will have an impact on micro and extend shelf life. (Private communication with Dr. Melette)
The claim for softer meat remains one that is hard to defend scientifically if one considers it from the vantage point of the action of lactic acid. There is, however, a benefit with ample scientific data to back it up and may result in more tender meat. The answer probably lays in what happens before rigor sets in, before ATP is depleted and before major lactic acid formation. It has to do with the salting of a carcass, immediately after death.
Prerigor salting results in a marked increase in water holding capacity (WHC) of the meat. If nothing else, this system achieves prerigor salting. “Hot salting” yields higher water holding capacity (WHC) and superior fat-binding characteristics in sausages despite the fact that salt increases the rate of ATP breakdown. As we have seen, the more rapid ATP depletion as a result of the salt should induce shortening. The high WHC of hot salted meat is, however, due to the “inhibition of rigor mortis in the fiber fragments resulting due to the combined effect of high pH and salt concentration before the ATP becomes depleted.” Studies have shown that the higher the salt concentration, the higher the WHC, up to a salt concentration of around 1.8%, but higher concentrations seem to have no material improved effect on the emulsion stability. Prerigor salting of meat results in increased solubilisation of the myofibrillar protein, but presulting does not appear to irreversibly protect the protein against loss of solubility. Although prerigor salted meat suffers from loss of myofibrillar protein solubility to the same extent as postrigor salted meat, its high WHC remains unchanged. Salted prerigor meat also maintains a high WHC during freezing and thawing. (Pearson, A. M.; 1989 : 424)
It is then indirect, through the improved WHC of the meat, that the meat is more tender. In the days of Morgan and Davis, the concern was primarily the preservation of the carcass and the meat was probably not immediately worked further.
One more note must be made about pH and micro-control. The fact that a complicated relationship between pH and micro exist has emerged over the past few years and tremendous work has been done showing that different bacteria are able to live across different ranges of the pH spectrum. It seems that the main benefit of the system, improving shelf life is then related to the decline in carcass temperature and the action of saltpeter and salt and the normal course of and benefits of curing. Temperature, pH, sodium chloride, sodium nitrite, phosphates, however, all work together in terms of the efficacy and mechanics of curing and in this relationship, a reduction of meat pH is beneficial, even though in terms of specific microorganisms, the benefit may be questioned.
Here in Dublin, we met amazing new friends. The old professor from the university who shared his information with us. The amazing and insightful Dr. Stamatis and our new friend from New Zealand. Stu extended an invitation for us to visit. He was very excited to introduce us to Simon O’Shea who hunts his own meat and who will tell us much about the treatment of meat while it is freezing cold. He works for Simon at the bacon plant in Christchurch.
Minette and I can report that we had the most amazing time in Dublin. It will forever be one of the greatest cities on earth! John Harris told me before we left that his company used injection with their dry-cured bacon from 1843.
Combining Injection and Dry-Curing
Some bacon curers use the dry-curing in conjunction with injection. In this case, the meat is injected with approximately 10% saturated brine solution and the injected meat is then treated the usual way in the application of dry-salt-cure. This was the method also used by Harris in the early days.
After it has been dry-cured, the meat is smoked at a temperature of not higher than 38 deg C (100 deg F) in order to prevent nitrate burn which presents itself as green spots that appear on the meat. Care should also be taken if these products are stored to prevent damage from insects such as cheese skippers, mites, red-legged ham beetles, and larder beetles. (Hui, Y. H., 2012: 540)
The injection was even used in the production of Barel Pork. A 1776 description is given on how barrel pork was produced.
“After the meat has cooled < probably after the hair was removed >, it is cut into 5 lb. pieces which are then rubbed well with fine salt. The pieces are then placed between boards a weight brought to bear upon the upper board so as to squeeze out the blood. Afterward, the pieces are shaken to remove the surplus salt, [and] packed rather tightly in a barrel, which when full is closed. A hole is then drilled into the upper end and brine allowed to fill the barrel at the top, the brine being made of 4 lb. of salt (1.8kg or 10%), 2 lb. of brown sugar (0.9kg or 5%), and 4 gallons of water (15L or 84%) with a touch of salt-petre. When no more brine can enter, the hole is closed. The method of preserving meat not only assures that it keeps longer but also gives it a rather good taste.” (Holland, LZ, 2003: 9, 10) Again, notice the brine make-up of salt, saltpeter, sugar mixed with water. The role of the sugar was to break the hard salt taste.
Barrel pork would remain an important curing method throughout the 1700s and would make a spectacular return almost 100 years later when pressure pumps were introduced to inject the brine into the meat through needles. A plank would be run across the barrel opening. The meat is placed on the plank for injection with between one and three needles. The three needles are fed brine through a hand pump that would pump brine directly from the barrel. The barrel is half-filled with brine. After the meat has been injected, it is pushed off the plank, to fall into the brine which acts as a cover brine. It would remain in the cover brine the prescribed time before it is removed and smoked.
Conclusion About Dr. Morgan and who Invented Meat Injection
It fascinates me that Ireland plaid such a pivotal role in pork production! Not only did they advance needle injection – but they also invented the mild cured system, now in use in Denmark and at the factories of C & T Harris. When we return to Calne, I expect that Oscar will be joining us for a visit within days. He sent me a message just before he boarded the ship. I am very excited to see him and show him the Harris operation. I dream of the day when I can take the two of you on a tour of the world to show you the different places I learned and introduce you to the many people who taught me.
Lots of love from Ireland!
Your Dad and Minette
(c) eben van tonder
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(1) Dr. Stamatis Papaikonomou, BOptom (RAU) FOA (SA) CAS DPA TPA (NECO),
Reg.Optometrist (HPCSA) Diagnostic Optometry, Assoc. Ophthalmology Society (SA).
He conducts research in Edenburg. Stamatis Papaikonomou is a full practicing member of the Professional Board for Optometry and registered with the Health Professions Council of South Africa (HPCSA). He holds undergraduate qualifications in Medical Technology MT (HPCSA)SCH, a Bachelors Degree in Optometry (RAU), and numerous post-graduate Advanced Studies International Programme (ASIP) Certifications in Vision Science (CAS DPA TPA) from The New England College of Optometry (NECO) Boston Massachusetts, U.S.A. His main field of interest is in Diagnostic Optometry, both adult and pediatric, for which he holds an additional category registration with the HPCSA. He is a Fellow of the Optometric Association SA (FOA), an Associate Member of the Ophthalmological Society SA, a member of the Glaucoma Society SA, and a member of the Medicolegal Society SA. His website is: https://www.eyecarecentre.co.za/johannesburg-specialist-optometrist-stamatis-papaikonomou.php
Photos from various sources on the web.