Since ancient times it has been seen the need to find methods of preserving food, to preserve its edibility and its nutritional values. In fact, the most obvious problem with food was certainly its conservation during the warmer months, especially. trovare dei metodi di conservazione del cibo, per preservarne la sua edibilità e i suoi valori nutritivi. Infatti, il problema più evidente riguardo al cibo era sicuramente la sua conservazione durante i mesi più caldi, specialmente.
There are various and all different methods that the ancients have experimented with and used over the centuries to preserve food, also depending on their physical characteristics
- sugar
- in vinegar
- zucchero per le marmellate
- salt and brine
- sterilization per conserve
- drying come per i pomodori
- smoke per carne e pesce
- fermentation
In this article we will see which are the traditional methods of food preservation that have been handed down over the centuries up to the present day and are still used today in modern homes.
Table of Contents
History of food preservation
Food preservation is as old as human civilization. Food storage inhibits spoilage caused by bacterial growth, oxidation, insects or drying .
The first humans, probably by trial and error, also began to develop basic forms of food storage, eg. drying, salting, fermentation .
The Chinese reportedly preserved vegetables by fermentation in prehistoric times and Pliny kept white cabbage in clay pots in Italy in the 1st century AD.
The first recorded cases of food preservation date back to ancient Egypt and the drying of cereals and subsequent storage in silos.
The stored grain could be stored for several years to ensure sustenance even in the event of famine or flooding of the Nile River.
Fermentation, packaging in oil, pickling, salting and smoking are all ancient preservation technologies.
Even refrigeration in caves or under cold water were well known ancient techniques of food preservation.
How food was preserved in Ancient egypt
In Ancient Egypt, with temperature fluctuations varying the temperature by many degrees from day to night, food storage was a priority.
For this reason, the Egyptians with their notorious ingenuity set out to excel in this practice too.
Usually, to preserve meat, it was macerated in lemon juice or sprinkled entirely with salt , regardless of the type of meat. They also preferred salt for other foods.
Cooked and salted meat was placed in large amphorae and jars, in which the Egyptians also placed the flour and wine.
These jars or amphorae were then sealed with clay, but on the mouth there was a cup that prevented the clay from falling on the food.
Fruit was almost always dried in the sun , especially if it was plums, dates and figs which were a delicious ingredient for sweet preparations.
Even the remains of uneaten food were never wasted: pigs were also used as "waste disposal" so as to prevent the appearance of insects and worms, carriers of infections and therefore a danger to population.
How did they do in the Hellenic world?
The diet of the ancient Greeks was very similar to our Mediterranean diet : in fact, at the base of their diet there were carbohydrates, vegetables, fish, wine (categorically diluted with water) and olive oil.
Fatto curioso: dopo la migrazione nel territorio del meridione italiano, i popoli greci hanno scoperto nuovi alimenti non presenti nelle loro zone.
Per questo hanno iniziato a preparare ricette talmente squisite, che i ricchi Romani volevano nelle loro case i cuochi di origine greca.
To preserve fruit, the Greeks used honey, but for fruits such as plums, apricots, figs, dates and grapes the drying method was used.
Instead, they used vinegar to preserve fish . Even today vinegar is widely used in the preparation of fish dishes, such as sarde in saòr .
Il vino, come la frutta, veniva conservato con l’aggiunta di miele, timo e altre erbe aromatiche.
I vini degli antichi Greci erano considerati di altissimo livello.
They often had an aftertaste of resin: pine resin was in fact used to seal amphorae.
Food preservation techniques in the Middle Ages
In the Middle Ages, but also in the centuries before and after, the preservation of food was not only practiced to prevent lack of sustenance in case of disasters.
In fact, dried, pickled, honey preserved or smoked foods were easier to transport by sailors, soldiers, merchants and so on.
Often, some foods were not found in certain regions of the territory and for this reason had to be "exported" from the areas where they were grown or raised (in the case of meat or fish, for example).
To be transported, however, even considering the transport times of the time, they had to be stored with the methods I listed above.
Drying was used for all types of food: cereals and fruit were usually dried in the sun, except in the coldest periods when the oven was used.
In areas of Scandinavia, the drying of cod , for example, was carried out in the cold after having gutted and deprived the head of the fish.
Salting was still the most common method to preserve meat and fish from the attack of bacteria and molds caused by humidity.
Meat was cut into strips, the salt was pressed on top and then it was operated by stratification with the addition of further salt in each space of the container in which the meat was stored.
L’affumicatura veniva adoperata per conservare pesce e carne (soprattutto di maiale).
Prima di essere esposta al fuoco, la carne veniva immersa brevemente in una soluzione salina per tenere lontane mosche e batteri.
The immersion step could be bypassed if the wood for smoking had a characteristic odor.
Why did they use honey instead of sugar?
You may wonder why honey was used instead of sugar to preserve fruit in sweet preparations ...
Well, because sugar was expensive to import and only chefs from wealthy families could afford it. Even the meat was occasionally preserved in honey.
Finally, fermentation . This method, unlike all the others mentioned above, accelerated the decomposition process of food.
Ciò che si faceva fermentare era l’alcol: il vino dall’uva, la birra dal frumento e l’idromele dal miele.
Così vino e idromele potevano essere conservati per mesi, mentre la birra si doveva consumare più velocemente.
Food preservation in the Victorian Era
Although the knowledge in the microbiological field of food preservation was still purely empirical, towards the end of the century, fortunately, refrigerators and pasteurization came into play.
The methods used had already been tested over and over again during the previous centuries: brine, sugar, alcohol, etc.
An apparently well-known recipe at the time was pickled mussels , but the habit of preserving eggs in oil and brine was also very common.
Anche la conservazione sottovuoto era già conosciuta nel Settecento, ma bisognerà aspettare i primi decenni del Novecento per poter trovare carne sottovuoto.
Tuttavia, veniva praticata nelle case soprattutto per conservare il latte, anche se il metodo più sicuro per avere latte sano era trasformarlo in formaggio.
pasteurization
Like Spallanzani, Pasteur in 1862 also started a series of experiments to counter the theory of spontaneous generation (of larvae in spoiled food).
Through these experiments he introduced the bases for the most known and used food preservation processes : sterilization and pasteurization .
What's the difference?
Sterilization takes place at high temperatures and for longer periods of time , allowing the elimination of all microorganisms.
La pastorizzazione invece, avviene sempre ad alte temperature, ma per un periodo di tempo più breve.
Viene utilizzato più spesso rispetto alla sterilizzazione per preservare le caratteristiche organolettiche e nutritive degli alimenti.
appertisation
A very important invention that will change the world of food is tin cans . Papin, a French scholar, invented these cans for the first time in 1818.
Spallanzani , Italian biologist, demonstrated that air could never generate life independently : through an experiment he demonstrated that flies did not arise spontaneously from meat damaged, but that direct contact between an adult fly and the meat was needed.
Nicholas Appert, scienziato francese, ha inventato (e non brevettato, tenetelo a mente) il metodo moderno della conservazione in scatola.
Ha infatti messo a punto una particolare bottiglia in grado di mantenere gli alimenti sottovuoto.
Questa tecnica è tuttora conosciuta come appertizzazione.
L’appertizzazione consiste nel bollire a bagnomaria il cibo fino a creare nella bottiglia un ambiente sterile e con il seguente raffreddamento la creazione del sottovuoto.
Not having patented this method of conservation, he gave way to Pierre Durand who instead patented a very similar method but with tin containers.
Grazie a John Hall e Bryan Donkin è avvenuto poco dopo il passaggio dai contenitori in stagno o in vetro a dei contenitori di latta, più leggeri e meno fragili.
Inizialmente venivano realizzati a mano dagli stagnini e poi nelle industrie addibite.
These cans were especially used by soldiers in warfare.
icebox
It was known that cold weather effectively prevented food from rotting , but it has always been difficult to understand and put in place a system to keep the temperature low.
Over the centuries, iceboxes have been used, which are underground rooms that were filled with pressed snow in winter.
Until the end of the Victorian era, these iceboxes were either common or belonged only to castles.
The first attempts at domestic refrigeration were the cupboards (wooden trunks that contained ice) as insulating as possible.
Ice was widely used in that period, so much so that many ice cream and sorbet recipes date back to the nineteenth century.
refrigerator
On May 6, 1851, the first refrigerator was patented that exploited the physics of gases to obtain cooling.
It was deposited by John Gorrie in the United States. Subsequently, various changes were made to his refrigerator prototype.
In the houses, the refrigerators entered only after the diffusion of the electric current.
These first refrigerators were very toxic because the gases of the circuit easily escaped, causing intoxication.
Before the twentieth century, refrigeration was a method that was used especially for the transport of food goods, which could be transported up to much greater distances.
What are the modern methods of food preservation?
Some traditional preservation methods are still used in our modern homes especially with regards to vacuum packing, pasteurization and drying in the sun.
Now let's see what are the methods of food preservation in the modern world and how conventional methods have improved.
vacuum and protective atmosphere
Estimates state that about 40% of food produced in developed Western countries is vacuum packed and 12% in MAP (Modified Atmosphere Packaging) .
It is widely used and safe because it prevents air, and therefore oxygen, from coming into contact with the food preventing its deterioration .
The vacuum does not guarantee the total absence of air inside the packaging because it would be materially impossible.
However, based on the percentage of air contained inside the package, two types of packaging can be distinguished:
- vacuum: attraverso macchine di potenza adeguata, viene eliminato l’l’85-90% dell’aria.
- hypobaric : with machines of reduced power, no more than 75% of air is eliminated. It is a commercial vacuum.
Thanks to the vacuum food can last 10 times longer , you can prevent the formation of mold and rot caused by certain bacteria and prevent the food from becoming rancid.
Among the disadvantages, however, we must remember that there are certain types of bacteria called anaerobic that live and proliferate in the absence of oxygen.
For example, lactic bacteria, which are responsible for the swelling of some packages.
These are "problems" that can be easily solved with MAP, but the latter has a higher cost and is used as a preservation method only for the finest foods.
Cold
It is a widely used system only in developed countries where large energy resources are available to maintain refrigeration units.
Depending on the temperatures, there are 2 ways to use cold as a method of preserving food:
- refrigeration : very fresh foods can be kept for a few days. Temperatures between 7 ° C and 4 ° C are usually maintained.
- freezing and deep freezing : there is no clear distinction between freezing and deep freezing. In both cases, almost all the water in a food is transformed into ice. However, to distinguish them we must evaluate the temperatures of the cooling process: in the first case they are around to -20 ° C / -70 ° C , in the second the temperatures are very low ( from -78 , 5 ° C of dry ice to -196 ° C of liquid nitrogen ) and shorter times.
Meat and fish frozen at home must still be consumed in the short term because even if there is no microbial proliferation, there are enzymes that degrade food down to -27 ° C.
Membrane separation and filtration
An immediate example of this method is certainly microfiltration of milk , used instead of pasteurization to eliminate microorganisms harmful to human health.
Semi-permeable membranes are used, with holes of different sizes, but still extremely small.
Obviously, with these techniques you can only treat liquid foods .
Thanks to this method it is possible to obtain a microbiologically pure food that lasts over time without the need to use heat.
Prevents the formation of enzymes that spoil food.
ionizing radiation
In the EU this practice is not currently authorized , while in many other countries around the world it is often used.
In Paesi come Stati Uniti, Canada, India e Brasile sono utilizzate soprattutto in alimenti di origine animale, come carni fresche e prodotti della pesca.
These are used to eliminate from the surface of the food microorganisms that are dangerous for human health.
It seems that radiation is also useful for combating the main viruses responsible for alimentary gastroenteritis.
additives
Additives are substances that are used for certain technological functions such as thickening, coloring and preserving.
Since 1990, all authorized food additives and their conditions of use have been harmonized at European level, in order to protect consumers' health and guarantee the free circulation of food products within of the EU.
The use of additives was immediately necessary for industrial preservation, but it was understood that the combination of other methods (such as those we have seen before) allows to avoid additives.
Some examples of additives: ethyl alcohol & nbsp; used in packaged bread prevents the development of fungi during commercial life; the citric acid in baby food in order to regulate acidity.
restaurants and food preservation
The system of food preservation and storage is extremely important for restaurants, in order to maintain its healthiness.
Innanzitutto è importante sapere che le merci che sono state acquistate in un tempo anteriore devono essere consumate prima.
Quindi i prodotti acquistati nuovi saranno posizionati dietro a quelli più “vecchi”.
If food products need to be refrigerated, thermometers are needed to keep the temperature under control at all times (you have to check every day):
Meat and vegetables must be kept separate and semi-processed food must also be kept apart.
Frozen products must be categorically stored at a temperature below -18 ° C which must be monitored every day.
Expired products must be thrown away immediately.
Dry products, on the other hand, should be kept at a temperature not exceeding 25 ° C and in a dry and ventilated place.
