Minerals — 10-20% (calcium 5%, phosphorous 4% and iodine).
Vitamins — Very rich in vitamins A, NS、 NS <サブ> 12 、 NS、 K and E.
Raw material:
The raw materials include fishes such as sardines, mackerels, ribbon fish, silver bellies and other fishes. Sharks and rays yield superior quality of fish meal. Fish meal is also obtained as a by-product of the canneries and fish oil industries.
Preparation of fish meal:
For manufacturing of fish meal the following methods are employed.
(a) Preparation for small scale production ：
The fish is first minced and then cooked. To remove moisture, the cooked mass is pressed in screw presses. The cake thus produced is dried in the sun, or in flame driers in which the material is exposed to high temperature or generally in steam-jacketed drums under partial vacuum.
(b) Preparation for large scale production ：
Here huge amount of raw material is used, that includes.
(i) Entire landed fish of poor food value,
(ii) Wastes from filleting plants (of canneries) and
(iii) Curing yards.
The raw materials, thus collected, are ground well to crush bone and flesh. The minced mass is then heated in steam, either by external application of steam (dry process) or by pressure-steaming through the minced mass (wet process).
Hydraulically operated pressing is then done and after extraction of oil and water, dry cakes are ready for sac filling and marketing. Fish meal is generally packed in gunny or coir bags, which are insect and vermin proof. Storage, if done in tin containers, is done under an atmosphere of nitrogen and with soldered lids.
Use of fish meal:
(1) Fish meal being a highly nutritive product (it contains all the essential amino acids) makes it an excellent poultry and animal feed which is practically good for all classes of livestock. By its use milk and egg production gets increased.
(2) As fish meal contains calcium, リン、 iodine and rich variety of vitamins, it is important for growing catties, for it promotes building of tissue and bone.
(3) Trash fish meal mixed with rice bran and vitamins, forms an excellent feed in aqua- culture.
9) Fish as a Source of Manure and Guano
Fish manure and guano are inferior quality of fish meal. It is not fit for animal consumption. Fish manure is a by-product of the curing yards, fish glue industries and oil extraction plants, where trash or spoilt fishes have been employed. Mackerel, horse mackerel, sardine, NS。、 which are spoilt and unfit for use as food is used for preparation of fish manure.
This manure has a high content of nitrogen (5-7%), phosphates about 4-6% and lime (CaO) 1-5%. For such nutrient content, fish manure is useful in raising coffee, tea and tobacco crops.
Fish guano is the by-product of the body oil extraction plant which is the dried refuse left after the oil is pressed out. Here oil bearing species such as oil sardines are used as raw material. Fish guano contains high concentration of nitrogen (8-10%) and appreciable quantities of phosphoric acid.このため、 guano is several times more effective than any animal manure.
10） Fish as a Source to Produce Fish Flour (Hydrolised Protein)
Fish flour is a superior quality fish meal, produced under strict control and care, and forms an ideal protein supplement for human diet, even for infants of 3-4 months old. On commercial scale, it is produced by a sophisticated solvent extraction process.
The process is complicated and is not expensive. Fish is chopped and washed. It is then boiled with dilute acetic acid at 80°C. The mass is then washed thoroughly and the water is pressed out.
This is then treated with petroleum to remove fat and also to increase its keeping quality. The mass, したがって、 obtained is then hydrolysed with an alkali, preferably with caustic soda (10% at 80°C). The entire mass is then liquefied when it is neutralised with acetic acid (85%). The liquid is then dried with a spray, which subsequently forms a dry, cream coloured powder.
Use of fish flour:
(1) It is considered as an ideal protein source to supplement diet for both adults and infants.
(2) It is used to enrich bakery products such as bread, biscuits, cakes and soup.
(3) As the product contains high protein (35%), it is very suitable for convalescing patients struck with malnutrition, anaemia, NS。
11） Fish as a Source to Produce Fish Silage
‘Silage’ generally means fodder converted in a cylindrical tank called ‘silo’. Fish silage is a liquid or semisolid fish meal and is a highly nutritive animal feed. It is produced by adding 3-4% of an acid to a minced fresh fish or fish offal. Generally formic acid is used but sulphuric or propionic acid can also be used.
By using these acids the pH of the mixture can be lowered to 4.0 or below. This inhibits bacterial decay. The enzymes present in the chopped fish act upon it and reduce the mixture to slurry. An antioxidant is added to prevent rancidity of fats and the liquid can be stored in a silo up to 6 months.
Fish silage is also obtained by fermentation with lactic acid bacteria in molasses. The advantage fish silage has over fish meal is that the vitamins remain unaffected to a large extent and the product is free from fishy odour. Its production is more preferred in temperate regions (Norway, Denmark, etc.) than in tropical countries.
12） Fish Solubles as a By-Product of Fish
The residual part of the liquid which is obtained during the extraction process of fish oil is known as fish solubles. It is valued as additives to dry feeds for animals.
It is rich in protein and vitamin B-complex and has the following composition:
Water —50.0%
Protein —33.9% (all essential amino acids)
Fat —2-6%
Ash — 9.4%
Vitamin B-complex and choline.
13） Fish as a Source to Produce Fish Sausage and Ham
Fish sausages are prepared from minced fish flesh that are stuffed into a prepared intestine or similar other casings. Fish ham, 一方で、 has small pieces of solid fish meat (pieces of one square cm), mixed with pasted fish meat. In both the preparation, spices and additives are added to improve the taste, flavour and keeping quality.
Spices include salt, シュガー、 チリ、 玉ねぎ、 corriander, glutamate, egg- white, hydrogenated vegitable oil, etc. Additives comprise antiseptics and antioxidants (ascorbic acid) to prevent rancidity. Colouring agents also may be added. These products are commercially manufactured in Japan, Russia and USA, and are prepared from less valuable trash fishes.
14) Fish is Used to Make Fish Macaroni
Macaroni is a pasta (flour and egg food preparation of Italian origin), prepared from wheat flour in the form of dried, hollow tubes. Fish macaroni is a product which is prepared from Puntius carnaticus. The fish is first minced and then mixed with tapioca or sorghum flour in equal parts.
It is then spiced with salt, chillies and tamarind. The product (paste) is extruded and dried. The product has good keeping quality, is cheap and easy to manufacture. It is manufactured on commercial scale by the Mysore Institute of India.
15） Fish is Used to Produce Fish Biscuits
Fish biscuits are manufactured in Chile and Morocco. It is blended with biscuit mixture prior to baking.
16) Fish as Source of Fish Glue
Fish glue is made by boiling the skin, bones and swim bladders of fish which has long been valued for its use in all manner of products.
Fish glue is a good adhesive obtained from trimmings, bones and skin of fishes belonging to order — Gadiformes (Cods, Pollack, Hakes, NS。）。 The raw materials are washed, chopped and steam-heated in steam-jacketed cookers.
The mass is then covered with water and to it is added small quantity of acetic acid. It is then cooked for 6-10 hours. The liquor is extracted and concentrated to form glue. The residue is dried and is used as manure.
Fish glue is used for:
(1) Smearing the backs of glued stamps and labels.
(2) Glue obtained from cod is of better quality and is used in photo-engraving.
(3) Low quality fish glue is used as adhesive for paper boxes, shoes and other things like furniture where joining is required.
17) Fish By-Product No. 17:Isinglass
Isinglass is a gelatin-like material obtained from the swim bladder or air-bladder of certain fishes. When put in water, it swells up but does not dissolve in it. At high temperature it hydrolyses in water to produce strongly adhesive gelatin.
Swim bladder is a hollow sac, the outer layer is thick and fibrous, while the inner one is thin, often with a silvery lustre. The thin, inner silvery shiny layer of the air-bladder of some fishes, such as sturgeons, carps and catfishes, is used to derive isinglass.
For preparing isinglass the air-bladders are collected, washed thoroughly to remove blood and other extraneous matters. Then the outer thick and fibrous layer of the wall is separated from the inner layer, which is exclusively isinglass raw material. This is then sun-dried and marketed.
Isinglass has the following uses:
(1) Isinglass is used mainly for clarification of wine, beer and vinegar.
(2) It is used for the preparation of special grade cement and plaster.
(3) Formerly it was used as a substitute for gelatin in confectionery.
18） 魚 Product No. 18:Fish Skin
The skin of larger fishes is collected, soaked in brine and left for a day. On the next day it is salted and again put in brine containing 10% hydrocholoric acid. The skin is then taken out, drained and scraped on the surface, particularly to remove fine denticles present in the skin of sharks. They are then limed and tanned by the usual process.
Fish leather has various uses, そのような：
(1) Natives of old age used the dried and spiny skins of Globe fishes or Porcupine fishes for making war helmets.
(2) In Japan the dried skin of Puffer fishes is inflated and used to make lanterns.
(3) Now-a-days the skins of larger fishes, such as cod, サーモン、 halibut, toadfish, sharks and rays are tanned and marketed as ornamental leather and can be dyed in different colours.
(4) Fish leather, particularly of sharks, is used in making shoes, wallets, bags and tobacco pouches.
(5) The skin of sharks, ray, skates are very hard and is used as an abrasive for polishing wood or metal.
(6) Suitably prepared and dyed skin of sharks providing ‘Shagreen’ issued for covering card cases, jewellery boxes, sword scabbards, NS。
19） Fishes Used for Artificial Pearls
The silvery scales of Europen cyprinid have been used for the manufacture of artificial pearls. By scrapping the scales, a glossy pigment is obtained. It is then coated on the inner surface and formed into hollow glass beads. The beads are then filled with wax.
20） By-Product No. 20:Fish Fins
The fins (except caudal fin) of shark are cut near the root, washed in sea water, dusted with a mixture of wood ashes and lime and dried in the sun or smoked. The cured product is crisp and brittle. In China and Philippines the shark fins are used in soup.
21) By-Product # 16. Fish Roe and Fish Caviar
Roe (mass of eggs or spawn) of a number of fishes is considered as food. The protein of roe is tasteless and its digestibility co-efficient and biological value are 81 % and 88%, それぞれ。 Roe fat is characterised by high lecithin (59%) and cholesterol (14%). Roe is a good source of vitamin B. It also has vitamins C, E and D.
Caviar is the processed and salted form of roe of any large sized fishes. The caviar of sturgeons is held in high esteem as a very delicious food and serves as an appetiser.
22) Processed fish products
Surimi refers to a Japanese food product intended to mimic the meat of lobster, カニ、 and other shellfish. It is typically made from white-fleshed fish (such as pollock or hake) that has been pulverized to a paste and attains a rubbery texture when cooked.
Fish glue is made by boiling the skin, bones and swim bladders of fish. Fish glue has long been valued for its use in all manner of products from illuminated manuscripts to the Mongolian war bow.
Fish oil is recommended for a healthy diet because it contains the omega-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), precursors to eicosanoids that reduce inflammation throughout the body.
Fish emulsion is a fertilizer emulsion that is produced from the fluid remains of fish processed for fish oil and fish meal industrially.
Fish hydrolysate is ground up fish carcasses. After the usable portions are removed for human consumption, the remaining fish body – guts, bones, cartilage, はかり、 お肉、 etc. – are put into water and ground up.
Fish meal is made from both whole fish and the bones and offal from processed fish. It is a brown powder or cake obtained by rendering pressing the whole fish or fish trimmings to remove the fish oil. It used as a high-protein supplement in aquaculture feed.
Fish sauce is a condiment that is derived from fish that have been allowed to ferment. It is an essential ingredient in many curries and sauces.
Isinglass is a substance obtained from the swim bladders of fish (especially sturgeon), it is used for the clarification of wine and beer.
Tatami iwashi is a Japanese processed food product made from baby sardines laid out and dried while entwined in a single layer to form a large mat-like sheet.
23) Other processed products
Pearls, mother-of-pearl, and abalone are valued for their lustre. Traditional methods of pearl hunting are now virtually extinct.
Sea horse, star fish, sea urchin and sea cucumber are used in traditional Chinese medicine.
The Sea snails Murex brandaris と Murex trunculus are used to make the pigment Tyrian purple.
Some sepia pigment is made from the inky secretions of cuttlefish.
24) Byproducts
A shimmery substance found on fish scales, most usually obtained from herring and one of many by-products of commercial fish processing, can also be used for pearlescent effects, primarily in nail polish, but is now rarely used due to its high cost, bismuth oxychloride flakes being used as a substitute instead.
25) Live Fish &Pets
Fish may also be collected live for research, observation, or for the aquarium trade.
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