Cured fish is fish which has been cured by subjecting it to fermentation, pickling, smoking, or some combination of these before it is eaten. These food preservation processes can include adding salt, nitrates, nitrite [1] or sugar, can involve smoking and flavoring the fish, and may include cooking it. The earliest form of curing fish was dehydration. [1] Other methods, such as smoking fish or salt-curing also go back for thousands of years. The term "cure" is derived from the Latin curare, meaning to take care of. It was first recorded in reference to fish in 1743. [2]
Salt is "the oldest and best known of preserving agents... its chief action appears to be due to its power of attracting moisture, and thus extracting fluid to harden the tissues"
According to Binkerd and Kolari (1975), the practice of preserving meat by salting it originated in Asian deserts. [4] "Saline salts from this area contained impurities such as nitrates that contributed to the characteristic red colour of cured meats. As early as 3,000 BC in Mesopotamia, cooked meats and fish were preserved in sesame oil and dried salted meat and fish were part of the Sumerian diet. Salt from the Dead Sea was in use by Jewish inhabitants around 1,600 BC, and by 1,200 BC, the Phoenicians were trading salted fish in the Eastern Mediterranean region. By 900 BC, salt was being produced in "salt gardens" in Greece and dry salt curing and smoking of meat were well established. The Romans (200 BC) acquired curing procedures from the Greeks and further developed methods to "pickle" various kinds of meats in a brine marinade. It was during this time that the reddening effect of salting was noted. Saltpeter (potassium nitrate) is mentioned as being gathered in China and India prior to the Christian era for use in meat curing... In Medieval times, the application of salt and saltpeter as curing ingredients was commonplace and the reddening effect on meat was attributed to saltpeter." [3]
Salt (sodium chloride) is a primary ingredient used to cure fish and other foods. [5] Removal of water and addition of salt to fish creates a solute-rich environment where osmotic pressure draws water out of microorganisms, retarding their growth. [5] [6] Doing this requires a concentration of salt of nearly 20%. [6] Iodized table salt may be used, but the iodine generally causes a dark end product and a bitter taste. Non-iodized salts like those used for canning and pickling foods and sea salt are the preferred types of salt to use for curing meats.
Sugar is sometimes added when curing fish, particularly salmon. The sugar can take many forms, including honey, corn syrup solids, and maple syrup. [7] Adding sugar alleviates the harsh flavor of the salt. [5] It also contributes to the growth of beneficial bacteria like Lactobacillus by feeding them. [8]
Nitrates and nitrites have been used for hundreds of years to prevent botulism in fish and ensure microbial safety. Nitrates help kill bacteria, produce a characteristic flavor, and give fish a pink or red color. [9] Nitrite is commonly used to speed up the curing of meat and also impart an attractive colour while having no effect on the growth of the Clostridium botulinum bacteria which causes botulism. [10] [11]
The use of nitrates in food preservation is controversial, and some traditional and artisanal producers avoid using them. This is due to the potential for the formation of nitrosamines when the preserved food is cooked at high temperature. [9] However, the production of carcinogenic nitrosamines can be potently inhibited by the use of the antioxidants Vitamin C and the alpha-tocopherol form of Vitamin E during curing. A 2007 study by Columbia University suggests a link between eating cured meats and chronic obstructive pulmonary disease. Nitrites were posited as a possible cause. [12] The use of either compound is carefully regulated. [9] For example, the FDA Code of Federal Regulations states that sodium nitrite may be safely used: "As a color fixative in smoked cured tunafish products so that the level of sodium nitrite does not exceed 10 parts per million (0.001 percent) in the finished product... As a preservative and color fixative, with or without sodium nitrate, in smoked, cured sablefish, smoked, cured salmon, and smoked, cured shad so that the level of sodium nitrite does not exceed 200 parts per million and the level of sodium nitrate does not exceed 500 parts per million in the finished product." [13]
Fish can also be preserved by smoking, which is drying the fish with smoke from burning or smoldering plant materials, usually wood. Smoking helps seal the outer layer of the food being cured, making it more difficult for bacteria to enter. It can be done in combination with other curing methods such as salting. Common smoking styles include hot smoking, smoke roasting and cold smoking. Smoke roasting and hot smoking cook the fish while cold smoking does not. If the fish is cold smoked, it should be dried quickly to limit bacterial growth during the critical period where the fish is not yet dry. This can be achieved by drying thin slices of fish.
In trade journals of the 1960s, the firms who sold nitrite powders to ham-makers spoke quite openly about how the main advantage was to increase profit margins by speeding up production.
The results show that there is no change in levels of inoculated C. botulinum over the curing process, which implies that the action of nitrite during curing is not toxic to C. botulinum spores at levels of 150ppm [parts per million] ingoing nitrite and below.
In food processing, brining is treating food with brine or coarse salt which preserves and seasons the food while enhancing tenderness and flavor with additions such as herbs, spices, sugar, caramel or vinegar. Meat and fish are typically brined for less than twenty-four hours while vegetables, cheeses and fruit are brined in a much longer process known as pickling. Brining is similar to marination, except that a marinade usually includes a significant amount of acid, such as vinegar or citrus juice. Brining is also similar to curing, which usually involves significantly drying the food, and is done over a much longer time period.
Smoking is the process of flavoring, browning, cooking, or preserving food, particularly meat, fish and tea, by exposing it to smoke from burning or smoldering material, most often wood.
Salting is the preservation of food with dry edible salt. It is related to pickling in general and more specifically to brining also known as fermenting and is one form of curing. It is one of the oldest methods of preserving food, and two historically significant salt-cured foods are salted fish and salt-cured meat. Vegetables such as runner beans and cabbage are also often preserved in this manner.
Smoked salmon is a preparation of salmon, typically a fillet that has been cured and hot or cold smoked.
Lox is a fillet of brined salmon, which may be smoked. Lox is frequently served on a bagel with cream cheese, and often garnished with tomato, onion, cucumber, and capers.
Smoked meat is the result of a method of preparing red meat, white meat, and seafood which originated in the Paleolithic Era. Smoking adds flavor, improves the appearance of meat through the Maillard reaction, and when combined with curing it preserves the meat. When meat is cured then cold-smoked, the smoke adds phenols and other chemicals that have an antimicrobial effect on the meat. Hot smoking has less impact on preservation and is primarily used for taste and to slow-cook the meat. Interest in barbecue and smoking is on the rise worldwide.
Pancetta is a salt-cured pork belly meat product in a category known as salume. In Italy, it is often used to add depth to soups and pasta.
Gravlax, gravlaks or graved salmon is a Nordic dish consisting of salmon that is cured using a mix of salt, sugar and dill. It is garnished with fresh dill or sprucetwigs and may occasionally be cold-smoked afterwards. Gravlax is usually served as an appetizer, sliced thinly and accompanied by hovmästarsås, dill and mustard sauce, either on bread or with boiled potatoes.
Norwegian cuisine in its traditional form is based largely on the raw materials readily available in Norway. It differs in many respects from continental cuisine with a stronger focus on game and fish. Many of the traditional dishes are the result of using conserved materials because of the long winters.
The origins of meat preservation are lost to the ages but probably began when humans began to realize the preservative value of salt. Sausage making originally developed as a means to preserve and transport meat. Primitive societies learned that dried berries and spices could be added to dried meat. The procedure of stuffing meat into casings remains basically the same today, but sausage recipes have been greatly refined and sausage making has become a highly respected culinary art.
Charcuterie is a branch of French cuisine devoted to prepared meat products, such as bacon, ham, sausage, terrines, galantines, ballotines, pâtés, and confit, primarily from pork.
Smoked fish is fish that has been cured by smoking. Foods have been smoked by humans throughout history. Originally this was done as a preservative. In more recent times fish is readily preserved by refrigeration and freezing and the smoking of fish is generally done for the unique taste and flavour imparted by the smoking process.
Curing salt is used in meat processing to generate a pinkish shade and to extend shelf life. It is both a color agent and a means to facilitate food preservation as it prevents or slows spoilage by bacteria or fungus. Curing salts are generally a mixture of sodium chloride and sodium nitrite, and are used for pickling meats as part of the process to make sausage or cured meat such as ham, bacon, pastrami, corned beef, etc. Though it has been suggested that the reason for using nitrite-containing curing salt is to prevent botulism, a 2018 study by the British Meat Producers Association determined that legally permitted levels of nitrite have no effect on the growth of the Clostridium botulinum bacteria that causes botulism, in line with the UK's Advisory Committee on the Microbiological Safety of Food opinion that nitrites are not required to prevent C. botulinum growth and extend shelf life..
Curing is any of various food preservation and flavoring processes of foods such as meat, fish and vegetables, by the addition of salt, with the aim of drawing moisture out of the food by the process of osmosis. Because curing increases the solute concentration in the food and hence decreases its water potential, the food becomes inhospitable for the microbe growth that causes food spoilage. Curing can be traced back to antiquity, and was the primary method of preserving meat and fish until the late 19th century. Dehydration was the earliest form of food curing. Many curing processes also involve smoking, spicing, cooking, or the addition of combinations of sugar, nitrate, and nitrite.
Salted fish, such as kippered herring or dried and salted cod, is fish cured with dry salt and thus preserved for later eating. Drying or salting, either with dry salt or with brine, was the only widely available method of preserving fish until the 19th century. Dried fish and salted fish are a staple of diets in the Azores, Caribbean, West Africa, North Africa, South Asia, Southeast Asia, Southern China, Scandinavia, parts of Canada including Newfoundland, coastal Russia, and in the Arctic. Like other salt-cured meats, it provides preserved animal protein even in the absence of refrigeration.
Fish preservation is the method of increasing the shelf life of fish and other fish products by applying the principles of different branches of science in order to keep the fish, after it has landed, in a condition wholesome and fit for human consumption. Ancient methods of preserving fish included drying, salting, pickling and smoking. All of these techniques are still used today but the more modern techniques of freezing and canning have taken on a large importance.
Cod and other cod-like fish have been widely used as food through history. Other cod-like fish come from the same family (Gadidae) that cod belong to, such as haddock, pollock, and whiting.