GB2371969A - Processing mackerel or herring - Google Patents

Abstract

Processing oily fish that has been filleted comprises tempering blocks of the frozen fillets to about -15 C, breaking the blocks, mincing the fish and making the minced fish into a burger or sausage using the fat from the fat seam present in the fish. The fish is mackerel, salmon, herring, sprats or anchovies that are rich in omega-3 fatty acid.

Description

FISH PROCESSING This invention relates to fish processing and especially but not exclusively to a method of preparing Mackerel, Horse Mackerel and Herring food products.

The main perceived problem of pelagic fish products is the presence of pin bones that have not been removed during processing. Indeed, the processing of fish is mainly directed at deboning using dedicated machinery.

This is relatively straightforward for white fish, for example Haddock, Cod, Whiting, Sole and Plaice. Their flesh can then be frozen and stored until required.

Frozen fish are known as having been laminated.

However, the process of deboning pelagic fish is much more difficult due to their bone structure, which has a number of bones protruding at right angles from the spine, see Figures 1 and 2. These bones are known as pin bones. Types of pelagic fish include Mackerel, Horse Mackerel, Salmon, Herring, Sprats and Anchovies.

An additional perceived problem of processing pelagic fish is that of rancidity of the fat.

Some species of white fish are used in the manufacture of products such as fishcakes or fish fingers. Pelagic species are commonly smoked, for example Herring for Kippers, Mackerel for Hot-Smoked Mackerel, Horse Mackerel

for fish meal, and Salmon for Cold Smoked Sliced Salmon.

Sprats and Anchovies are usually canned.

However, to be able to supply an edible product such as burgers or sausages manufacturers are required to process fish in a similar manner to that of red meat, for example by the addition of further ingredients including rusks, water and saturated fats. A lack of these ingredients results in a dry product with a substandard consistency and a reduced shelf life.

Attempts have been made to produce sausages form herring, using pork fat as an added ingredient. (See for example, Torry Advisory note no. 43,""Delicatessen fish products" by R. McLay. However, pork fat is high in saturated fat, which is known to have associated health risks.

It would therefore be desirable to be able to use a healthier alternative to the saturated fat, for example polyunsaturated fat.

The described process uses the polyunsaturated fat common in pelagic fish, Omega 3 Fatty Acid.

Omega 3 Fatty Acid, has been recognised by many leading Scientists, Nutritionists, Dieticians and Doctors as having a number of health benefits including prevention of circulatory problems, reduction of the risk of diabetes and thrombosis, relief for arthritis sufferers, inhibition of tumour development and acceleration of improvements in psoriasis.

In the past, fish sausages have been produced from white fish, with high grade fish oil as a supplement. Such a process is described in Japanese Patent document JP60110266. However, the use of Omega 3 as the polyunsaturated fat is preferable to the use of high grade fish oil, as the latter is known to have potentially adverse effects. (See Journal of Human

Nutrition and Dietetics (1998), 11, pages 13 to 19, Minnis et al.,"Oily fish and fish oil supplements in the prevention of coronary heart disease"). The use of oil as a supplement also gives an undesirable soft oily texture.

Mackerel, Herring and Horse Mackerel are particularly rich in Omega 3 Fatty Acid, which is also known to provide essential oils for embryo and brain development.

In these species a polyunsaturated fat seam rich in Omega 3 runs lengthwise along the body, as shown in Figure 1.

This fat seam is regarded by food manufacturers as being problematic and undesirable.

On cooking, burgers and/or sausages made form these species, the taste is not unlike that of ordinary burgers and sausages made from red meat. As a result of this similarity in taste, the development of burgers and/or sausages based on these species would provide a healthy alternative to the types of burgers and sausages currently consumed.

There are a number of further health benefits associated with the use of mince derived from these species. The products contain no harmful additives being comprised solely of pelagic fish mince, polyunsaturated fat, antioxidants and seasoning.

In addition, these species have not had any of the health warnings associated with beef.

Thus the use of processed pelagic fish mince in food products, such as burgers and/or sausages, would provide a healthy alternative to the burgers and sausages that are currently on the market. The current production of burgers and sausages is over 250,000 tonnes per year in Britain. When it is remembered that these products contain 40-70% saturated fat, a known cause of serious health problems, the need for a healthy alternative is

highly desirable. In addition, the market for healthy option and vegetarian products is continually growing.

It would therefore be desirable to have a method for processing these pelagic species into a form suitable for making food products whilst it is still frozen.

It is an object of the present invention to provide a method for processing these pelagic species such that it may be used in a number of different types of food.

According to a the present invention there is provided a method for processing fish fillets comprising the steps of: tempering frozen laminate blocks in a chill room until the temperature increases to about -15oC ; placing the laminate blocks in a pre-breaker for breaking up the blocks prior to a subsequent mincing step; feeding the fish into a mincing machine, the mincing machine comprising a funnel, a slicing mechanism and a collection drum; collecting and processing the minced fish into an edible product, and; using fat derived from the fat seam of the fish as a substitute for the use of saturated fats.

Preferably the fish fillets can be directly processed into sausages and/or burgers.

Preferably the type of fish that can be processed is either Mackerel (Somber Scombus L. ), Horse Mackerel (Scad) or Herring (Clupea Herengus).

The slicing mechanism may comprise a plurality of blades.

Preferably the funnel is attached to a worm. The worm can be used to begin the mincing process.

More preferably, the mincing machine comprises a circular plate. The circular plate may comprise a number of apertures for allowing the minced fish to pass through the plate.

Preferably the slicing mechanism is tight to the circular plate.

In order to provide a better understanding of the invention, an example of the invention will now be described with reference to the accompanying Figures, in which Figure 1 illustrates a side view of the position of the fat seam of a pelagic fish; Figure 2 illustrates a cross-sectional view of the position of the fat seam of the fish; and Figure 3 illustrates a mincing machine used in the process of the present invention.

Referring firstly to Figures 1 and 2 a pelagic fish is generally depicted at 1. A fat seam 2 is situated between two bodies of flesh 3. A series of pin bones 4 extends from a backbone 5.

Referring to Figure 3, a mincing machine is generally depicted at 6 comprising a funnel 7, a worm 8, a series of blades 9 and a circular plate 10 and a collection box 11. The circular plate 10 contains a plurality of openings (not shown) with a diameter of about 1/8th inch (3.2mm).

The pelagic species, having been filleted, skinned and frozen (laminated), may be processed in the following way. The laminated blocks would be stored at a temperature of about -27oC. Before production, they would

be put in a chill room for tempering until the temperature has increased to about -15oC. Subsequently, the blocks would placed in to a pre-breaker which would break up the blocks prior to the mincing step.

The broken blocks are then fed into the worm 8 via the funnel 7. The fish passes through the worm 8 and is shredded by the blades 9. The shredded fillets then pass through the apertures in the circular plate 10 and are collected in the collecting box 11. The minced fillets can then be processed into an edible product, for example the sausages and/or burgers.

After the product is formed into shape, it is frozen and then coated prior to cooking. For example it may be battered and crumbed. This has the advantage of protecting the fats and anti-oxidants thus extending the shelf-life of the product.

The main advantages of the present invention are that the mentioned pelagic species would be processed into a form that could readily be incorporated into eg sausages. The processing and product manufacture could be done using current technology and therefore neither expensive retraining or machinery would be required.

A further advantage of the present invention is that it provides a method for the use of Omega 3, previously considered to be problematic and undesirable in terms of food production. These so-called'oily fish'are virtually the only source of this beneficial fat. Plants such as oil-seed rape, and linseed oil are rich in Omega 3, but they have to go through a rendering process in order to extract the high grade oil. The heating process involved could have an adverse effect on the chemical composition of the oil.

Pelagic species are also considerably cheaper to procure

than the red meats currently used, such as beef, and they have the additional advantage that they do not carry the press stigma relating to BSE and E-Coli. Mackerel, Horse Mackerel and Herring are notably cheaper than red meat.

Current technology for the production of burgers and sausages requires the presence of a high fat content to produce an edible product. However, if white fish based products are made, their low fat level requires the addition of animal fat or fish oil to the ingredients making them unsuitable for vegetarians and/or reducing their health value.

Thus the manufacture of pelagic fish products would have a number of benefits in terms of health and a wider potential market.

Alternatively, the fat seam of the pelagic fish may be extracted and used in other food products, as a replacement for saturated fat.

Further modifications and improvements may be made without departing from the scope of the invention herein intended.

Claims (1)

1. 'CLAIMS' Application number GB 0031594.5 Page 4 Claim 1 A method according to claim 1 wherein (Lines 13-25) A method for processing fish fillets comprising the steps of, tempering frozen laminated blokes in a chill room until the temperature increases to about-15 degrees C, placing the laminated blokes in a pre-breaker for breaking up the blokes prior to a subsequent mincing step; feeding the fish into a mincing machine comprising a funnel, a slicing mechanism and a collection drum; collecting and processing the minced fish into an edible product, and using fat derived from the fat seam of the fish as a substitute for the use of saturated fats.

   Claim 2 A method according to claim 1 wherein (Lines 27-28) Preferably the fish fillets can be directly processed into sausages and/or burgers.

   Claim 3 A method according to any preceding claim wherein (Lines 30-32) Preferable the type of fish that can be processed is either Mackerel (Somber Scombus L.), Horse Mackerel (Scad) or Herring (Clupea Herengus).

   Claim 4 A method according to any preceding claims wherein (Line 34) The slicing mechanism may comprise a plurality of blades.

   Claim 5 A method according to any preceding claims wherein (Line 36) Preferably the funnel is attached to a worm. The worm can be used to begin the mincing process Page 5 Claim 6 A method according to any preceding claim wherein (Lines 1-4) More preferable, the mincing machine comprises a circular plate. The circular plate may comprise a number of apertures for allowing the minced fish to pass through the plate Claim 7 A method according to any preceding claim wherein (Lines 6-7) Preferably the slicing mechanism is tight to the circular plate.