Salmon is a popular food. Classified as an oily fish,[1] salmon is considered to be healthy due to the fish's high protein, high omega-3 fatty acids, and high vitamin D[2] content. Salmon is also a source of cholesterol, with a range of 23–214 mg/100 g depending on the species.[3] According to reports in the journal Science, however, farmed salmon may contain high levels of dioxins. PCB levels may be up to eight times higher in farmed salmon than in wild salmon,[4] but still far below levels considered dangerous.[5][6] Nonetheless, according to a 2006 study published in the Journal of the American Medical Association, the benefits of eating even farmed salmon far outweigh any risks imposed by contaminants.[7]
Salmon steak (left) and fillets (right)
in a market
Salmon flesh is generally orange to red, although there are some examples of white-fleshed wild salmon. The natural colour of salmon results from carotenoid pigments, largely astaxanthin but also canthaxanthin, in the flesh.[8] Wild salmon get these carotenoids from eating krill and other tiny shellfish. Because consumers have shown a reluctance to purchase white-fleshed salmon, astaxanthin (E161j), and very minutely canthaxanthin (E161g), are added as artificial colourants to the feed of farmed salmon, because prepared diets do not naturally contain these pigments.[citation needed]
In most cases, the astaxanthin is made chemically; alternatively it is extracted from shrimp flour. Another possibility is the use of dried red yeast or microalgae, which provide the same pigment. However, synthetic mixtures are the least expensive option. Astaxanthin is a potent antioxidant that stimulates the development of healthy fish nervous systems and enhances the fish's fertility and growth rate. Canthaxanthin may have negative effects on the human eye, accumulating in the retina at high levels of consumption.[8]
Today, the concentration of carotenoids (mainly canthaxanthin and astaxanthin) exceeds 8 mg/kg of flesh, and all fish producers try to reach a level that represents a value of 16 on the "Roche Colour Card", a colour card used to show how pink the fish will appear at specific doses. This scale is specific for measuring the pink colour due to astaxanthin and is not for the orange hue obtained with canthaxanthin. The development of processing and storage operations, which can be detrimental on canthaxanthin flesh concentration, has led to an increased quantity of pigments added to the diet to compensate for the degrading effects of the processing. In wild fish, carotenoid levels of up to 25 mg are present, but levels of canthaxanthin are, in contrast, minor.[8]
A simple rule of thumb is that the vast majority of Atlantic salmon available on the world market are farmed (almost 99%[9]), whereas the majority of Pacific salmon are wild caught (greater than 80%).
Canned salmon in the U.S. is usually wild Pacific catch, though some farmed salmon is available in canned form. Smoked salmon is another popular preparation method, and can either be hot or cold smoked. Lox can refer either to cold smoked salmon or to salmon cured in a brine solution (also called gravlax). Traditional canned salmon includes some skin (which is harmless) and bone (which adds calcium). Skinless and boneless canned salmon is also available.
Raw salmon cured in salt, sugar, and dill. Usually served as an appetiser, sliced thinly and accompanied by hovmästarsås (also known as gravlaxsås), a dill and mustard sauce, either on bread of some kind, or with boiled potatoes.
A side dish consisting of fresh tomato and salmon salad. It was introduced to Hawaiians by early western sailors.[13] It is typically prepared by mixing raw salted, diced salmon with tomatoes, sweet gentle Maui onions (or sometimes green onion), and occasionally flakes of hot red chili pepper, or crushed ice. It is always served cold. Other variations include salmon, diced tomato, diced cucumber, and chopped sweet onion.
A fillet that has been cured. In its most popular form, it is thinly sliced—less than 5 millimetres (0.20 in) in thickness—and, typically (in North America), served on a bagel, often with cream cheese, onion, tomato, cucumber and capers. Lox in small pieces is also often added and cooked into scrambled eggs, sometimes with chopped onion.
A type of fishcake made mostly from salmon in the style of a hamburger. It is challenging to make and cook as the salmon requires a binder to make it stick together and is easy to overcook which makes it too dry.[15] Salmon burgers are especially common in Alaska where they are routinely offered as an alternative to beef hamburgers.[16]
A preparation of salmon, typically a fillet that has been cured and then hot or cold smoked. Due to its moderately high price, smoked salmon is considered a delicacy. Although the term lox is sometimes applied to smoked salmon, they are different products.[17][18]