Classifications

• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23K—FODDER
  • A23K50/00—Feeding-stuffs specially adapted for particular animals
  • A23K50/80—Feeding-stuffs specially adapted for particular animals for aquatic animals, e.g. fish, crustaceans or molluscs
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23K—FODDER
  • A23K10/00—Animal feeding-stuffs
  • A23K10/20—Animal feeding-stuffs from material of animal origin
  • A23K10/22—Animal feeding-stuffs from material of animal origin from fish
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23K—FODDER
  • A23K10/00—Animal feeding-stuffs
  • A23K10/20—Animal feeding-stuffs from material of animal origin
  • A23K10/26—Animal feeding-stuffs from material of animal origin from waste material, e.g. feathers, bones or skin

Definitions

• the invention regards a soft feed for fish, e.g. for feeding farmed fish and fish caught alive and kept alive in netpens or closing nets or other suitable devices. More particularly, the invention regards an extruded and pelletized feed which when soaked in water and subjected to a mechanical influence loses its structure, forming a pasty, coherent soft mass. This pasty mass may be formed into desired portions for fish, either manually or by extruding the mass through a suitable orifice.
• the advantage of this may be the ability to regulate the market, providing a more regular supply of wild caught fish, thereby obtaining a better price for the fish.
• Another advantage is that smaller fish with a lower market value can be fed to obtain bigger fish with a higher market value. This can be combined with delivering the fish out of season, thus achieving an even higher price.
• This type of practice has been established for live caught cod (Gadus morhua) , pollock (Pollachius virens) , southern blue-finned tuna (Thynnus maccoyii) and northern blue-finned tuna (Thynnus thynnus) .
• Farmed fish including farmed cod and halibut (Hippoglossus hippoglossus) , are accustomed to a dry formulated feed from the moment it has used up the nutrition in the yolk sac, or possibly following a short period of being fed algae, rotifers, and possibly brine shrimp (Artemia) .
• Such fishes will therefore accept a dry formulated feed as food, and will grow well on this type of feed.
• the degree of utilization of the feed is high, as very little of the feed introduced will sink through the netpen and go to waste.
• a formulated fish feed here means a feed composed of one or more sources of protein, including but not limited to marine proteins such as fish meal and krill meal, vegetable proteins such as soy flour, rapeseed flour, wheat gluten, corn gluten, lupine flour, pea flour, sunflower flour and rice flour, and slaughterhouse waste such as blood meal, bone meal, feather flour and chicken flour.
• sources of protein including but not limited to marine proteins such as fish meal and krill meal, vegetable proteins such as soy flour, rapeseed flour, wheat gluten, corn gluten, lupine flour, pea flour, sunflower flour and rice flour, and slaughterhouse waste such as blood meal, bone meal, feather flour and chicken flour.
• a formulated feed further includes a source of energy in the form of e.g. fish oil and/or vegetable oils such as rapeseed oil and soybean oil.
• a formulated feed also contains a binding agent, ordinarily in the form of farinaceous (starchy) ingredients such as wheat or wheat flour, potato starch or tapioca flour, peas or beans, in order to give the feed the required solidity and stability of shape.
• a formulated feed will contain the minerals and vitamins required to ensure good growth and good health for the fish.
• the feed may contain additional additives such as e.g. colouring agents to achieve certain effects.
• a formulated fish feed is a composite feed in which the quantitative proportions of proteins, fats, carbohydrates, vitamins, minerals and any other additives are calculated to suit the nutritional needs of the species, based on the age of the fish. Ordinarily, only one type of feed is used, and so each piece of feed is of full nutritional value.
• a dry formulated feed here means a feed of a pressed or extruded type.
• a pressed feed will normally contain less than approximately 10% water after pressing and possibly the application of oil.
• An extruded feed will contain between 18 and 28% water following extrusion. After being extruded this feed goes through a drying step, and subsequently an oil application step.
• the final product will contain approximately 10% water or less, and as a result will be highly storable, as the water activity in these feeds is low so as to prevent the growth of mould and fungus, and also avoid bacterial decay.
• Dried and pressed or extruded feed may be of different shapes and sizes.
• a common shape is a cylindrical piece of feed where the length-to-diameter ratio is normally between 1 and 1.5.
• Such pieces of feed are termed pellets.
• the size of the pellet is proportionate to the size of the fish, thus the diameter of the pellet can be between 1 and 30 mm.
• the fish feed industry has found it difficult to produce feed pellets of a diameter larger than 30 mm.
• the difficulties associated with drying such pellets in reasonable time are cited as one problem.
• Another problem is the lack of solidity, which causes a lot of dust and breakage.
• a dry pressed or extruded fish feed will retain its shape in water for several hours and up to several days unless subjected to external mechanical influences.
• the pellet contains a binding agent in the form of starch.
• the binding agent has been added to provide the pellet with sufficient strength to allow it to be stored and transported in e.g. big bags that hold from 500 kg to 1000 kg of feed, or to tolerate storage in feed silos and pneumatic transport through production plants, during loading and unloading, and between the feed plant and the individual netpens.
• the dimensional stability in water is also partly due to the pellet being covered in fat, leaving an external oil film, and possibly also oil-filled pores and cavities, to inhibit the ingress of water.
• the pellet will disintegrate after a period in the water, forming a loose granular mass. This process can be accelerated by subjecting the pellet to external mechanical loads. On a laboratory scale this may be done by stirring the water or directly squeezing or picking at the pellet. The water and pellet will form a grainy thin paste consisting of large and small particles.
• Live caught fish has fed on various types of prey and is not used to eating a dry formulated feed.
• the dry formulated feed differs from the prey in shape, colour, consistency, smell, taste and movement, and so it has turned out that live caught fish needs a transitional period or adaptation period before it accepts a dry formulated feed as food.
• the attempt to make the fish adapt to such feed is entirely unsuccessful.
• An example of this is the southern blue-finned tuna. This fish weighs around 15 kg when caught and is sold at a weight of between 30 and 60 kg. Ordinary feed pellets with a diameter of between 10 and 20mm are too small for the fish to care about, in addition to which such feed pellets do not have an appetizing texture.
• a soft consistency is achieved by having a significantly higher content of water than the approximately 10 % found in dry feed.
• a soft feed is basically a paste which can contain all of the required nutrients, and which is formed into pieces of feed, manually or by extruding it through an orifice e.g. in a sieve plate. Presumably it is the soft texture that makes this feed more acceptable to the fish than dry feed. After the fish has become accustomed to a soft feed this feed can continue to be used until the fish has reached the desired size. Alternatively the fish can adapt to a dry formulated feed after accepting the soft feed as food.
• Soft feed also called semi-moist feed
• semi-moist feed is commonly used in fish farming.
• it is common for the farmer to prepare the feed himself during the early development phase of the fish farming.
• Such feeds typically contain 40 % water or more.
• the soft feed is replaced by industrial feed of the pressed or extruded type.
• Soft feed is normally made from whole fish, chopped fish or fish offal. This is mixed with a binding agent, often in the form of starch, but also alginates, and possibly fish oil or other cooking oils, and possibly also vitamins, minerals and other required additives, in a grinder and shaped into pieces of feed by extruding this through a sieve plate.
• a binding agent often in the form of starch, but also alginates, and possibly fish oil or other cooking oils, and possibly also vitamins, minerals and other required additives, in a grinder and shaped into pieces of feed by extruding this through a sieve plate.
• the size of the feed pieces is generally determined by the diameter of the orifice.
• the paste may be shaped into feed pieces manually.
• the raw fish materials are obtained frozen or fresh. Frozen raw fish materials may be thawed before grinding, but some types of grinders can also grind frozen fish.
• the dry raw materials such as binding agents, vitamins and minerals can be mixed in advance and come as so-called premixes. It is also possible to mix in dry protein materials such as fishmeal, and wet protein materials such as e.g. fish ensilage.
• An alternative to soft feed is to feed the caught live fish with whole fish or bits of fish. This may be fresh fish or frozen fish that is thawed immediately before feeding. Some fish farmers let whole blocks of frozen fish float on the water. As the block thaws, the fish or pieces of fish fall off and become available as food.
• the extrudate When producing fish feed by means of an extruder the extrudate contains a maximum of 30% water. Prior to drying, this extrudate is soft and flexible. It is known for this extrudate to be preserved through freezing instead of drying. The farmer will then thaw the feed prior to feeding.
• Soft feed requires either a regular supply of fresh raw materials or access to frozen raw materials. A regular supply of fresh raw materials may be made difficult by seasonally conditioned fisheries. Poor weather conditions will also affect the availability. Alternatively use can be made of frozen raw materials, which requires access to cold storage. The same holds for the availability of whole fish or pieces of fish.
• An additional disadvantage of a soft feed is the fact that it is not formulated.
• a soft feed is compact, and it is difficult to control the density of the feed.
• a soft feed will sink quite quickly in water compared with a dry formulated feed of the extruded type. This means that there will be a greater waste of soft feed compared with dry extruded feed in situations where the fish has become accustomed to the respective types of feed.
• Frozen extruded feed requires an unbroken chain of refrigerated transportation means from the producer to the farmer. This requires more expensive and more complex logistics than the transportation of a dry feed.
• the simplest and cheapest way of freezing feed pellets is to package the feed in bags, e.g. 25 kg bags. The bags are then placed in cold store. Fish feed has good insulating properties, and so it takes time for a bag to become frozen through. In some instances the core does not freeze and a lot of fungus, mould and bacteria will develop at the centre of the bag during storage and transport. This will not become apparent until the bag is thawed and opened, when the damaged feed mixes with the rest of the feed.
• An alternative method of freezing is to freeze the pellets prior to packing, by using e.g. a tunnel freezer. This technology raises the price of the product .
• a known method of increasing the storage life of moist products is to package these in a modified atmosphere or vacuum-pack them. This makes certain demands on the packaging and requires dedicated packing equipment.
• the object of the invention is to remedy or reduce at least one of the drawbacks of prior art.
• the object of the invention is to arrive at a fish feed which is soft when fed out to fish, especially caught fish, while at the same time retaining the beneficial properties of the extruded dry feed in terms of formulation relative to the specific requirement of the fish in question, and the simple logistics associated with the extruded dry feed, from producer to fish farm.
• the soft feed shall be adaptable to different sizes of fish, and advantageously it is possible to form larger pieces of feed than that which is possible in conventional fish feed production based on extruder technology.
• Soft feed refers to a feed containing more than 15 % water. In particular, it refers to a feed containing more than 20 % water, and a water content of more than 30 % is even more beneficial to the soft texture. Feed containing more than 30 % water cannot be produced by use of conventional extruder technology. Such a soft feed has a texture that is beneficial when it comes to making live caught fish adapt to a formulated feed. Surprisingly, it has turned out that by using known raw protein materials such as e.g.
• an extruder which in terms of pressure and temperature conditions and the ratio between thermal and mechanical energy is set so as to make the starch in the extruded material exhibit the properties required for the feed pellets to exhibit the desired novel property of forming a soft coherent paste.
• This paste may be shaped into pieces of feed of a desired size by pressing it through a suitable orifice in e.g. a sieve plate or by manual shaping. Such shaping makes it possible to achieve larger pieces of feed than those that can be achieved in the production of dry extruded pellets.
• the feed is produced by the dry raw protein materials and binding agents being ground and mixed with vitamins and minerals and any other desired components.
• This mixture is passed through a known preconditioner in which steam, possibly water, possibly oil and possibly fish silage is added to the mixture before it passes into a known extruder such as a single screw or double screw extruder.
• a known extruder such as a single screw or double screw extruder.
• the mixture is worked, and any additional steam, water, oil or fish ensilage is added here, so as to impart the intended property to the starch fraction before the mass is forced out through the die base and the extrudate is cut to the desired length by a rotary blade.
• the holes in the die base may be between 1 mm and 25 mm.
• the desired length may be shorter than the diameter of the pellet and up to twice the length of the pellet, or longer if expedient.
• the water content of the extrudate may be between 18 and 28 %.
• the extrudate After being cut, the extrudate passes through a known dryer, e.g. a vertical drying tower or a horizontal belt dryer, and is dried to a water content of less than 10 %. Following dehydration, more oil may if so desired be applied to the pellets by use of known techniques, e.g. a vacuum coater. Following dehydration and any application of oil, the pellets are cooled in a known manner, sieved free of dust and particles and packaged.
• a known dryer e.g. a vertical drying tower or a horizontal belt dryer
• suitable receptacle Prior to being fed out, the desired quantity of dry extruded feed in accordance with the invention is placed in a suitable receptacle and liquid is added to the pellet.
• suitable receptacle also refers to e.g. a bag or other packaging such as the packaging in which the feed is delivered.
• the quantity of liquid added to the dry pellet is not more than that which can be absorbed by the pellet, while at the same time being sufficient to give a pasty consistency.
• the amount of added liquid constitutes between 20 % by weight and 200 % by weight of the pellet. More preferably the amount of added liquid constitutes between 25 % by weight and 100 % by weight of the pellet. Even more preferably the amount of added liquid constitutes between 30 % by weight and 80 % by weight of the pellet. Most preferably the amount of added liquid constitutes between 30 % by weight and 60 % by weight of the pellet.
• the liquid may be fresh water, seawater, fish ensilage, size water or another protein containing liquid such as a mixture of water and fish entrails, or a mixture of two or more such liquids.
• the temperature of the liquid may be the same as that of the surroundings or it may deviate from this.
• liquid refers to a liquid composition of one or more of said liquids and materials.
• the soaking time is between 1 minute and 24 hours. More preferably the soaking time is between 1 minute and 12 hours. Even more preferably the soaking time is between 1 minute and 6 hours. Most preferably the soaking time is between 1 minute and 90 minutes.
• the soaked feed is worked into a coherent soft paste.
• the working may be done by a rotary arm or screw located in the receptacle, or by lowering a suitable device into the receptacle.
• a suitable apparatus for shaping the pieces of feed.
• Such a suitable apparatus may be a simple grinder in which an auger carries the paste through one or more suitably sized and shaped orifices in a sieve plate.
• the length of the pieces of feed can be decided by means of a rotary blade, or by the string breaking off under its own weight.
• the soaked but still distinct pellets may be transferred to a suitable device for working the pellets into a mass.
• a suitable device for working the pellets into a mass.
• Such a device may be a grinder. Working (kneading) and shaping the feed into pieces will then be carried out in one operation
• the mixing receptacle there may be associated with the mixing receptacle an arrangement having one or more suitably sized and shaped orifices.
• the paste in the mixing receptacle can for instance be pressed against the orifice arrangement by a suitable device such as a rotary arm that presses the paste against the wall of the receptacle. Outside the receptacle the paste may be cut into suitable lengths or the string of paste will break off under its own weight. Still other arrangements can be envisaged, which would achieve the desired mechanical working of the soaked feed in accordance with the invention.
• An alternative method involves mixing whole fish or fish offal in with the dry pellets prior to soaking, or mixing in whole fish or fish offal after soaking but prior to working or kneading to form a paste, or mixing fish or fish offal into the prepared paste before shaping pieces of feed through a sieve plate.
• a person skilled in the art will know that the preparation of the paste and the shaping of the pieces of feed can take place on shore or on a floating structure, and that the pieces of feed can be transported to the netpens in a known manner and be distributed in the netpen in a known manner.
• the preparation of the paste and the shaping of the pieces of feed can take place in direct connection with the netpen, such that the shaped pieces of feed will fall directly into the netpen or is distributed across the surface of a netpen or in several adjacent netpens by means of simple devices.
• the paste may be prepared in one place and the pieces of feed shaped in another place, all depending on what is most expedient .
• a feed in accordance with the invention was prepared according to the following recipe:
• the dry feed contained 54 % protein, 17 % fat and 5 % water.
• the produced feed was soaked for about 20 minutes at a ratio of 6 kg of water to 10 kg of feed. A web of spaces had formed between the loose pellets, allowing the water to distribute easily and all the pellets to soak. After soaking it was easy to form a soft paste by kneading the feed by hand.
• the feed paste contained approximately 40 % water, approximately 34 % protein and approximately 11 % fat.
• the produced feed was soaked for about 30 minutes at a ratio of 9 kg of water to 10 kg of feed.
• the feed paste contained approximately 50 % water, approximately 28 % protein and approximately 9 % fat.
• the wet feed pellets were also worked by an ordinary mincer, Soft spaghetti shaped strings were formed after passing through the sieve plate of the mincer.
• the shaped pieces of feed exhibited a good ability to sink in water and were stable in water for a period exceeding the time it takes for feed to sink through a netpen.
• a feed in accordance with the invention was prepared according to the following recipe:
• the dry feed contained 47.6 % protein, 17.7 % fat and 10.6 % water.
• the feed was worked into a paste and pieces of feed were shaped by rolling the paste by hand, into pieces having the sizes of golf balls and tennis balls. These pieces of feed were given to live stored pollock.
• the pollock had a weight of between 300 and 400 g. Compared with feeding of ordinary dry extruded feed, the pollock displayed a great appetite. Pieces of feed the size of golf balls were eaten whole, while the pieces of feed the size of tennis balls were eaten piecemeal.
• a soft feed in accordance with the invention can be used for feeding farmed fish that has lived all the stages of its life under controlled conditions.
• Another application is recreational fishing, where the pasty feed can be used as bait on a hook. It may further be used as bait to attract wild fish to a baited hook, by throwing small pieces of feed out into the water around the fishing spot.
• the pasty feed may further be used by professional fishermen, as bait on hooked fishing equipment and as bait in fishpots, fish traps and other stationary fishing gear.

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• Life Sciences & Earth Sciences (AREA)
• Polymers & Plastics (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Food Science & Technology (AREA)
• Zoology (AREA)
• Animal Husbandry (AREA)
• Physiology (AREA)
• Molecular Biology (AREA)
• Biotechnology (AREA)
• Biomedical Technology (AREA)
• Health & Medical Sciences (AREA)
• Marine Sciences & Fisheries (AREA)
• Insects & Arthropods (AREA)
• Birds (AREA)
• Fodder In General (AREA)
• Feed For Specific Animals (AREA)

Priority Applications (4)

Applications Claiming Priority (4)

Publications (1)

Family

ID=37482079

Family Applications (1)

Country Status (8)

Cited By (6)

Families Citing this family (2)

• 2006
  • 2006-05-18 NO NO20062227A patent/NO20062227L/no unknown
  • 2006-05-29 CA CA002609805A patent/CA2609805A1/en not_active Abandoned
  • 2006-05-29 EP EP06747658A patent/EP1887882A2/de not_active Withdrawn
  • 2006-05-29 JP JP2008514575A patent/JP2008541756A/ja active Pending
  • 2006-05-29 KR KR1020077030348A patent/KR20080039346A/ko not_active Withdrawn
  • 2006-05-29 WO PCT/NO2006/000199 patent/WO2006130015A2/en not_active Ceased
  • 2006-05-29 AU AU2006253158A patent/AU2006253158A1/en not_active Abandoned
• 2007
  • 2007-11-30 DK DK200701711A patent/DK200701711A/da not_active Application Discontinuation

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