2.1.1 The fins on sharks
Most species of sharks have at least two sets of median fins situated along the central line of the body. There are one or two dorsal fins on the top, a caudal fin, which is the tail, and an anal fin located at the underside behind the anus. Most sharks have triangular dorsal fins. There are usually two, the first being generally larger than the second, but in some species there is only one. The caudal fin is asymmetrical with the vertebral column extending into the upper lobe. The anal fin is not present in all species. Its absence or presence is important in shark classification. They also have two sets of paired fins on the underside of the body. These are the pectoral fins just behind and, in some cases, partly below the gill slits and the pelvic fins located at about the midpoint of the underside of the body. As with all the fins in sharks, the pectoral fins cannot be folded back and are consequently erect all the time.
Of the 350 or more species of sharks, less than 50 species have fins of commercial importance. The fins are mostly imported in the dried form, complete with denticles and cartilaginous platelets. The trade commonly calls these the raw fins.
FigureFigure 1 Fins on the shark
2.1.2 The structure
A shark fin has very little muscle tissue. There is a membrane, and in some cases a fatty layer under the skin, covering a bundle of collagen fibres spread out like a fan. In most fins these fibres are supported by a cartilaginous platelet in the centre. The cartilaginous platelet is absent in the caudal fin.
Sharks do not have scales. The skin of the fins, like that of the rest of the sharks body, is covered with large numbers of usually very small thorn-like structures or denticles. These make sharkskin feel like sandpaper.
The collagen fibres of the fin are rounded at the base, tapering to fine points at their extremities, giving the appearance of needles. Appropriately, they are commonly known as fin needles. Separately or joined as a bundle, the fin needles will eventually find their way in different preparations onto the dining table
2.1.3 The chemical composition
Nutritionally, the composition of 100 g of dried sharks fin needles is as follows:
Source: Food Composition Tables, People's Health Publication, Beijing
* The protein of shark fin lacks the essential amino acid Tryptophan.
2.1.4 The traditional background
Shark fin as a food was reported in writings of the Ming Dynasty (1368 -1644). It has therefore been known in China for at least a few hundred years. Throughout the ages, the Chinese have considered shark fin one of the eight treasured foods from the sea. The fact that so little is obtained from such a large fish made fins noble and precious, fit for the tables of the emperors. Fins were indeed listed as articles of tribute when officers of coastal regions visited the emperors in the Imperial court. (Yang, Lin and Zhou)
Fins are traditionally served at dinner parties to express the hosts respect for his guests. To this day the practice still holds true in Chinese communities. They are most frequently consumed on auspicious occasions, such as weddings.
2.1.5 The health benefits
The benefits of shark fin as documented by old Chinese medical books include the following: rejuvenation, appetite enhancement, nourishing to blood, beneficial to vital energy, kidneys, lungs, bones and many other parts of the body.
The more traditional person will swear to the benefits as claimed. On a radio show when the owner of a shark fin restaurant was asked about the health benefits of shark fin, he claimed that he consumed it daily and thus maintained his youthful appearance. An elderly shark fin trader reasoned that, since fins have had long years of exercise in the sea, there is no doubt that they are good for the bones and muscles of the consumer.
However, there seems to be an increasing number of people who question the claimed benefits of fins. They are of the opinion that fins are over priced and over rated. Their main purpose as luxury products is to satisfy the vanity of those who can afford them.
Most consumers note the bland taste of fin needles, which need to be cooked with various tasty ingredients to acquire any flavour. Few commented on the transparency of the fin needles, which make the food appealing to the eye.
2.2.1 The criteria for value
Commercially, the factors affecting the value of the fins are:
1. The percentage yield of fin needles. From an economic standpoint, the fin that yields a higher percentage of fin needles is better value for money. The yield in turn is governed by a number of factors:
The type of fin, e.g. the lower lobe of the caudal fin has no cartilaginous platelet, therefore, compared to other types of fins, this has the highest percentage yield of fin needles. The upper lobe of most species does not yield fin needles so, after removal of the denticles, the skin is dried and sold as fish lips. The variations in sizes of fin needles are vast. Generally, the larger the fin, the longer and thicker are the fin needles. The caudal fin by comparison is the largest fin of the fish, therefore yields the thickest and longest fin needles, followed by the first dorsal fin and then the pair of pectoral fins. The fin needles from the second dorsal fin, the pair of ventral fins and anal fin are considered to be of much lower quality.
The species, e.g. the whole caudal fin of the shovel Nose Ray yields fin needles from both the lower and upper lobe. The fin needles of Basking shark are reputed to be as thick as a chopstick while fin needles from some fins are finer than hair.
The processing methods employed, e.g. whether the fin is clean cut or has shark meat attached, whether it is light and dry or been salted and thus has a high moisture content. The trade in general is weary of ageing fins. In such cases, certain parts of the fin lose their natural elastic property and acquire a hard bony structure, which is not palatable. Unfortunately, ageing in the fin is not easily detected when dry, i.e. at time of purchase. When the ageing becomes visible after rehydration it has to be discarded. It is reported that this phenomenon is more common in species inhabiting tropical waters, as the environment makes the sharks age faster. (Yang, Lin and Zhao).
2. The general appearance A good fin product would be clean cut, with no meat or other undesirable attachments at the cut edge. The surface of the washed fins should be a whitish yellow. Generally, when the fin needles are connected in a bundle and/or are long and thick, they would present a greater visual and sensual impact to the diner, thus commanding a higher price than the shorter and finer ones.
3. The texture: The connoisseur often demands a specific fin for its texture, usually tenderness. In such cases this criteria takes precedent over length or thickness. The very thick fin needles from very large fins have a tendency to be tough.
2.2.2 The quality of supply
Some countries are able to produce better quality sharks fins than others. They are usually those with a developed fishery, having adequate infrastructure and post harvest technology. This enables the fins to be kept fresh and clean and unsalted before drying. The producing countries which fall into this group include the Americas, Japan, Australia, Mexico and Spain. Of these, Mexico and Australia provide the best value for money.
Countries around the Indian Ocean are more traditional in their shark fin processing methods and, combined with the lack of infrastructure, the fishermen and processors of these countries are more inclined to use salt for preservation. This results in inferior products with high moisture content. These countries are also resistant to change with a philosophy that as long as the products sell there is no reason to change. An exception in this group, according to an importer, is Sri Lanka, which adheres to tradition yet is able to produce a good product.
2.2.3 Methods of consignment
Importers purchase shark fin in various different ways, depending very much on how the suppliers sort the fins. Some sort the fins into three categories as follows:
First grade fins, i.e. the white fins, in sets of three, which consist of two dorsal fins and a caudal fin. The sets are of the same species and the same sizes are packed together. The size in this case is determined by the length of the first dorsal fin.
Second grade fins, i.e. the black fins, graded by species and size. If sold in sets, the size referred to would be that of the pectoral fin.
Second grade bottom fins; anal and pelvic fins of mixed species and sizes.
Others sell in 1-2 tonne lots, mixing species and sizes. Using this method, importers report losses of 2-3kg of choice fins of choice species per lot.
The international trade customarily classifies fins into white and black groups. Some traders say that this is a description of the colour of the fins, others that it is a classification by their yield and taste and a third version maintains that shark fins of the white group belong to sharks from shallow waters while the black belong to sharks from deeper waters. The former have a set of three fins, two dorsal and a caudal fin, whereas the latter have a set of four, a pair of pectorals, a dorsal and a caudal fin.
All agreed however that fins of the white group give higher percentage of fin needles and a better flavour. These are more sought after and thus command higher prices. Fins from the black group are inferior in both percentage yield and flavour. The classification is used in the trade the world over but there are other differences in opinion. For instance, the fins of Tiger sharks are considered to be white by one Indian authority and black by another. (See section 6)
Within Singapore and Malaysia traditional names are also used, often following those used in Hong Kong but not always. A number of names were also created by some traders, mainly to confuse buyers so that the latter would have difficulty duplicating the order from another supplier.
2.2.5 Identification of species
Most larger traders of shark fin know exactly what they are dealing with. They can tell by looking at a raw fin its position on the shark, its trade name and its country of origin. Not many know the common or scientific names of the sharks but, with the existing knowledge of the product, it seems highly likely that the species could be identified if traced back to the source of supply. The identification of species from fin needles is extremely difficult except, perhaps, for some large fin needles.
The smaller traders are usually vague on the background of their shark fins. As for the restaurant trade, it is claimed that not many know about fins in relation to the properties of the various species. The priority of most restaurants is the price of the fins. They usually stay with what they know and seldom tread into unknown territory. When change is inevitable, they normally take the advice of their suppliers.
This is the process that renders the fin needles of the dried shark fin soft and ready for cooking. The resultant fins are termed wet fin and those that are not required for immediate use are often re-dried or frozen. The re-dried fins are called cooked fins. The steps involved in the processing of raw fins are as follows:
2.3.1 Removal of the denticles
Depending on the size, thickness and species of the fin, this process involves soaking the fins in water varying from lukewarm to 60°C. Some need to be repeatedly heated over a slow fire for up to five hours. When the skin and the denticles are sufficiently soft to work with, the denticles are removed by scratching with a small knife or wire brush.
Photograph 1.1 Removing denticles from sharkskin
2.3.2 Removal of the cartilaginous platelet
The fin is cut from the broad edge to loosen the fin needles on either side of the cartilaginous platelet, taking care not to cut open the fan shape, so that the fin still remains in a joined piece after the platelet is removed.
Fins are trimmed to remove any undesirable waste material and to give it a tidy appearance. (Photograph 1.2) The fins at this stage are ready for the market as wet fins. They can also be frozen or re-dried for later use.
The fins are usually bleached to give them a desirable whitish colour. The methods include smoking with sulphur overnight (Liu, Li and Niu) or treatment with 3 % hydrogen peroxide for about 30 minutes (Subashingha).
Photograph 1.2 Trimming a fin
2.4 Products in the market
"Raw" fins are complete with skin and cartilaginous platelet, where present. Their colours vary with the species, but are generally grey black, light brown or yellowish. The denticles on the skin make the surface rough to the touch. These are usually found in importers, wholesalers and sometimes in retail outlets. (Photograph 1.3)
Photograph 1.3 Raw fins
Cooked" fins have the denticles and the cartilaginous platelet removed. They are yellowish white in appearance and the surface is smooth to the touch. These are sold in wholesalers and retailers outlets.(Photograph 1.4)
Photograph 1.4 Cooked fins
Fin needles, dried in random arrangements or in rows. These products are usually not prepared from choice fins. They are found in wholesalers and retailers outlets. (Photographs 4.4 and 4.5)
2.4.2 Ready to cook products
Wet fins are rehydrated ready to cook fin needles. They are sold in supermarkets and retail outlets for the restaurant and the home consumer. Some processors add sodium carbonate to the soak water to accelerate the rehydration process and increase the rate of water absorption by over 250 %. Using established processing methods, one kilogram of raw fin yields 0.75 to 1.5kg of wet fins, the cleaner the cut of the raw fin, the higher the yield. The addition of sodium carbonate will yield 4kg of wet fins from 1kg of raw fins. Wet fins processed this way look plump and juicy but shrink once heat is applied. Sodium carbonate is generally used only in the rehydration of more robust fishery products such as dried cuttle fish and octopus, because it removes fatty materials from the product and may affect its nutritional values. (Wang Zhe Yue)
Frozen fins - Fin bundles are frozen ready for use. These are usually sold in retail outlets to home consumers. (Photograph 4.6)
Powdered shark fin soup, ready to cook, sold in retail outlets. (Photograph 4.7)
2.4.3 Ready to eat products
Canned and pouched products of various fin preparations are sold in retail outlets. Most are products of Singapore and Thailand. (Photographs 4.8 and 4.9)
Sashimi and sushis are sold in selected supermarkets. The fins used are usually of Japanese origin. (Photograph 4.10)
2.4.4 Artificial shark fin
This is a Japanese product with the appearance and, to some extent, the texture of shark fin. Because of its looks and its comparatively very low price, some restaurants use it instead of shark fin with or without the knowledge of the consumer. To make the dishes more authentic, the restaurants usually mix artificial fins in with shark fin in a 30/70 ratio. It is probably most used at wedding dinners, where the respect for the dinner guests is upheld with the presence of fins, and the respect for the hosts' finances is taken care of by lower costs.
A trained person can easily tell the difference between the artificial fins and the shark fin. Generally, the artificial fins are less elastic, break more easily and do not withstand heat as well as the real thing. It is not so easy for the untrained to know the difference, especially since most diners' experience of shark fin is rather limited. The price of artificial fins is Rm30/kg.
The Singapore Government has closed restaurants that tried to pass the artificial fins off as the real thing. The Malaysian Government allows its use by restaurants as long as it is sold as artificial fins.
A small number of traders have experienced a general decrease in the supply of shark fin. One importer in particular informed me that the quantities offered by his suppliers have reduced tenfold since the 1950s. Most other traders have yet to experience any shortage. However, some observed an increase in smaller size fins. This could be the result either of more smaller sharks being caught or of an improvement in processing technology to handle smaller size fins.
Some observed that increasing pollution and higher water temperature has driven many sea inhabitants such as bêche-de-mer, to deeper cooler waters. They reason that, in the same way, sharks may also become less available to those fishermen without appropriate fishing gears to meet changing conditions.
Most are optimistic that the sharks will be in the seas for many years to come. Those familiar with fisheries in developing countries argued that management of resources are governed by economic forces. The shark fishermen, in their effort to safeguard their livelihood, do not find it economically viable to fish in one area for too long. After some time they move to another area and do not return to the same area for several years. In many developing countries, fishing sharks for fins is just as much fishing sharks for meat; it is a necessity in the hunt for food and income.
On the other hand, conservationists reported that at least 50 000 blue sharks landed by long line fishermen are tossed back in the water after their fins are removed. The numbers of some shark species may have plummeted by 80 % over the last decade. (Michael D. Lemonick, Time)
The only thing that everyone is sure of is that prices of shark fin will only increase. As societies become more affluent and traditional ethnic food products, such as shark fin, become better known world-wide, the demand for them will increase. Against the back drop of meeting increasing demands, more sharks will be fished and the price of shark fin will continue to rise.