Curing (food preservation)

Salting ( from Romanesque piccare, " sting " borrowed ), in Austria and Bavaria, also called Suras, is a well known since ancient method of preserving meat and sausages using nitrite ( a mixture of table salt and sodium or potassium nitrite) or a mixture of table salt and saltpetre ( sodium or potassium nitrate). During the Pökelvorgangs it comes through the use of nitrate or nitrite to the so-called reddening, ie the meat gets a bright red color. Canned meat is commonly called salt beef or salt meat, more general than the product group cured meats or especially raw cured when no pretreatment was performed, otherwise cooked cured. In the absence of nitrite use is also spoken of salts or salt meat.

The term curing is expected as a synonym for salting on the Dutch Gillis Beukel († 1397 ) go back, which should have but have not used the usual nitric later.

• 4.1 methemoglobin
• 4.2 nitrosamine formation
• 4.3 Reactive nitrogen formation

Action principle

Meat products are untreated by oxidation of the dye fast muscle pale and spoil by stocking with unwanted or harmful to health microorganisms such as Pseudomonas.

Salting delayed this by different mechanisms

• In the flesh existing microorganisms lose water by osmosis from their cytoplasm, which affects their cellular functions and proliferation. Technologically, this water activity is lowered in the product.
• Nitrite also acts specifically against the anaerobic botulinum bacterium ( Clostridium botulinum) and prevents its spread
• The nitrite combines with the muscle pigment to nitrosomyoglobin and thus provides a visually appealing red color; this process is called reddening.

There is also the typical " Pökelaroma ". However, the curing some of the proteins contained in meat is lost. In addition, the Nasspökeln also important to go at the beginning existing minerals in solution. You are here displaced by the highly concentrated brine salt from the meat. Instead of nitrite use, some manufacturers today sea salt or iodized table salt, but sea salt can be charged nitrite depending on the origin. The use is then compared with the use of nitrite.

Method

That usually pre-dried meat can be cured in various ways, there are traditional and regional variants. In particular, spices and other aids such as ascorbic acid can be used in addition to the pickling salt yet.

Dry method

In the dry method, the meat is rubbed with curing salt or covered in layers and layered. The tissue fluid is removed by osmosis, the result is the " self- Lake ". This process may take up to six weeks, depending on the amount of meat, but due to the high fluid withdrawal of up to 50 %, it will provide the best durability. It is still to distinguish between the "real" Dry cured, when the meat juices can flow and brining in its own brine, in this case exceeds the meat juices after a few days the pieces of meat, so that the process later in the Nasspökeln is comparable.

Nasspökeln

For curing, the meat is placed in a brine. The water also diffuses by osmosis so long from the meat cells in the Lake until the salt concentration in the flesh of the concentration of the corresponding Lake. The process time is shorter with about four weeks as the dry method, but reaches a lower shelf, because fewer cell is leaking. For the same reason the meat juicier in this process.

Schnellpökeln

Under Schnellpökeln refers to labor-intensive variants of the dry or Nasspökelns to shorten the duration of the procedure. Some of the methods may be used in combination.

Both the meat and the Pökelgefäß be rubbed with curing salt and the meat then stacked tightly. After two days, the meat is turned over. Curing is about five to seven days.

Here, the brine is injected directly into the meat, thereby the process time is reduced to an average of three days.

In this method, after the injection of brine the meat piece is mechanically flexed to distribute the liquid directly in the flesh.

By generating a vacuum, the outlet of the tissue liquid is supported, the process time is reduced by even two days per kilogram of the biggest piece of meat.

Elopement

Often the meat is not processed directly after curing itself ( smoked, air-dried ), but it is first a so-called burn-through phase. Here, the salt supply is stopped (ie, that the meat is taken from the Lake or the salt), the diffusion now takes place only in the flesh piece, thereby setting the same salt content in the entire piece over time.

Pickling salt

The use of normal saline produces a fluid reduction of the meat and thus a reduction of the bacterial growth. However, it is not effective against the gray color of the meat and has a lesser inhibitory factor against the bacterium Clostridium botulinum on. For this purpose, the saline is added in small amounts of nitrate or nitrite, in recent times gave the normal impurity of the salt. Course Inserted nitrate is converted by the bacteria into nitrite in meat as the active substance. The process time is prolonged. The nitrite combines with the muscle pigment myoglobin to nitrosomyoglobin and further to the heat-stable nitrosomyochromogen, which produces the red color. A further improvement in the preservation effect is achieved by the addition of ascorbic acid as an antioxidant.

Health Concerns

Methemoglobin

Nitrites can oxidize as a strong oxidant hemoglobin to methemoglobin. Oxygen transport is impaired. For young children this can be dangerous, the enzyme methemoglobin reductase methemoglobin in adults transformed back into hemoglobin.

Nitrosamine formation

By reaction of nitrites with amino acids nitrosamines may arise which are considered carcinogenic. This is the reason that ( speculative) concerns regarding the consumption of Toast Hawaii or pepperoni pizza came up: nitrites from the meat used could at high temperatures with proteins, such as those of the cheese, form nitrosamines.

The Faculty of Food Technology at the University of Applied Sciences Berlin then analyzes corresponding dishes were made and have shown no higher nitrosamine levels found than in dishes that are considered safe.

At the German Cancer Research Center, it is assumed that the registered decrease in gastric cancers was due to the decreased use salted or smoked foods. In addition, epidemiological studies would suggest a positive correlation between the intake of nitrite from meat and meat products and certain cancers.

In contrast, the Federal Research Centre for Nutrition and Food pointed out, however, that such foods were responsible for only about 3 % of the daily nitrite intake and a significantly greater proportion came from the recording fertilized vegetables or from metabolic processes.

Reactive nitrogen formation

Contain a common diet with foods that nitrite or nitrite, such as ham or sausage, increase according to one study, the risk of developing COPD ( Chronic Obstructive Pulmonary Disease ). Cause the formation of reactive nitrogen compounds seem to be, which could lead to structural changes ( emphysema -like ) into the lungs.

Food regulations, sorted by product groups in Germany regulate the use of nitrite and nitrate. Nitrite, for example, may be added in combination with nitrite curing salt. In addition Registration Regulation, the maximum permissible amounts of residual nitrite and nitrate in the finished product, for example, regulated.

Pickling salt is to food law in the EU as E249, E250 regulated, E251, E252 and shall be marked accordingly.

Distribution in Europe

About 80 to 90 percent of all processed meat and sausages are According to the Association of potash and salt Industry in Europe salted.

Historical

Salting is a very old method of preservation, which was very common during long voyages, so meat was present as a protein source on the high seas. In Hanseatic charters in 1300 this method of preservation is mentioned. And Herodotus describes the salting of meat, it existed in Rome for the Salsamentarii. Even in ancient saltpeter was used to preserve food. 1891 discovered the chemist Eduard Polenske ( 1849-1911 ) that nitrate is converted to nitrite by bacteria in the meat. Karl Bernhard Lehmann and Karl Kißkalt 1899 discovered that nitrite is responsible for the reddish color of dry-salted. 1901 John Scott Haldane showed that the reddish color comes from a chemical reaction of the nitroso group with the included meat hemoglobin. In 1929, it was found that the bacterial growth is slowed down by nitrites.

Salting in other cultures

Salting as a method of preservation is used in many cultures, increasingly just where hardly any cooling devices are present. For longer storage of untreated meat is possible. Another reason is that meat is carried on the long routes of herders.

In Brazil - especially in the arid north-east - there are Charque, carne do sol and carne seca, which differ by the amount of used salt and the type of additional drying that occurs in carne do sol in the blazing sun, and the the flesh varies greatly withdraws water. It is exclusively made ​​of beef, the preferred type of meat of the population, and is produced, for example, an ingredient of the Brazilian national dish, feijoada.

In the Trieste kitchen called Calandraca is prepared with salt pork.