GB2170392A - A process for manufacturing a meat product - Google Patents

Abstract

In a process for manufacturing shaped meat products, meat pieces are massaged with metallic salt solutions to concentrate salt soluble proteins onto the meat surface to act as a binder, additives and flavourings are added and the resultant mixture rapidly frozen by contact with a refrigerant e.g. carbon dioxide "snow" or liquid nitrogen at approximately -100 DEG C. The mixture is subsequently shaped and formed whilst remaining at a low temperature and the resulting shape is retained after thawing.

Description

SPECIFICATION A process for manufacturing a meat product This invention relates to a process for manufacturing a meat product. In particular but not exclusively it relates to the preparation of shaped and formed articles made from poultry meat.

There is a large demand for meat products which have a relatively uniform predetermined shape. This shape may have little relation to the shape of pieces of meat from butchered animals and may be met by using meat in finely minced form mixed with a binder to bind the pieces together and hold them together before, during and after cooking. A typical product of this kind is a beefburger in which binding is achieved by mixing minced meat with breadcrumbs and water and allowing time for the breadcrumbs to soak up the water and the mix to stiffen before shaping and cooking.

For many products however it is desirable that larger pieces of meat are used, possibly ones that arise naturally such as poultry muscles. It is possible to bind these pieces using gelatine but this does not allow much scope for moulding or shaping into small uniform products where for example about 3 pieces of meat are included in the final article.

Furthermore gelatine tends to break down during the cooking process and leaves gaps between the meat pieces, spoiling the appearance of the product.

The present invention provides an improved process which enables pieces of meat of various shapes to be incorporated into relatively uniformly shaped articles.

According to the present invention there is provided a process for manufacturing shaped articles from pieces of meat wherein a fluid or particulate substance at a temperature below 0 C, and acting as a refrigerant, is applied to the pieces of meat and acts to cool the meat, the refrigerant substance being such that itvapourises and disperses from the meat during cooling, and subsequently forming shaped meat articles, each article comprising at least one piece of meat moulded whilst remaining at a temperature below the freezing point of water.

In one application of the process each article comprises a plurality of meat pieces.

In a preferred process the pieces of meat are formed into articles at an average temperature within the range 0 to -6 C.

In preferred embodiments of the invention the refrigerant is provided at a temperature much lower than the eventual temperature of the meat.

Carbon dioxide or nitrogen at a temperature of approximately -100"C may be used as the refrigerant. Carbon dioxide may be used in the form of a snow-like fine powder below about -80 C and can be injected into a vessel containing the meat pieces, while they are being agitated, to make contact with all the surfaces of the meat pieces.

Thus cooling is achieved without the pieces sticking to the sides of a refrigerator or being cooled irregularly according to their position in the bulk. In cooling the meat, the carbon dioxide is itself heated and vapourises, dispersing from the meat. Nitrogen can be injected in a similar fashion, although it is a gas at -1000C and needs to be injected at a greater rate since it disperses quicker. Although many fluid or finely particulate substances may be used as effective refrigerants, care should of course be taken to ensure that the chosen substance is compatible with animal tissue and will not taint or otherwise degrade the meat product or make it unfit for human consumption.

The invention allows relatively large chunks or pieces of meat to be used, such as whole muscles from, for example, chicken breast fillets. Although a few pieces may become ruptured or torn by the processing, the majority will remain whole, improving the texture and appearance of the final products.

Depending on the nature of the desired product, the meat pieces to be processed according to the invention may be initially massaged with a salt solution and/or have a small proportion of comminuted skin and flavourings added in the wellknown manner to achieve a range of differently textured and flavoured products.

After undergoing the cooling steps of the invention the meat product may be shaped and formed by any desired method, such as by extrusion or by moulding in a three-dimensional mould, followed by a coating of, for example, breadcrumbs or batter.

Embodiments of the invention will now be described by way of example only.

A process for manufacturing chicken articles of dimensions for example of about 7 cm x 3 cm such as schnitzels containing chicken pieces comprises the following steps: 1. Slaughtered chickens are deboned and deskinned by hand or by machine; the machines for deboning poultry are well-known. The meat is removed in the form of whole pieces of muscle and is checked by hand to be free of all particles of bone or other inedible material.

2. The pieces of meat are transferred to a massaging machine where a solution of an edible metallic salt, such as sodium chloride is added, the brine being at a concentration of between 4 and 20% by weight. Any other desired additives and flavourings may be added at this stage. The mixture is massaged and tumbled in the machine to concentrate salt soluble proteins in the meat onto the surface of the meat. These proteins are highly viscous and serve to bind the meat pieces together.

Although a few pieces of meat may be ruptured at this stage the majority will remain as whole pieces of unbroken muscle.

3. The skin which has been previously removed from the meat is very finely minced to a fine paste or emulsion and a small portion of this is added to the meat/brine mixture. The skin coats the surface of the pieces of meat with an emulsion of protein and fat and serves three main purposes; it helps to bind the meat pieces together, flavours the product and helps to lubricate the meat pieces during the forming process outlined as step 6 below.

4. The meat mixture is introduced into a mixer, which is then sealed. A controlled volume of carbon dioxide "snow" at a temperature of approximately -1 00 C is injected into the mix while the mix is being tumbled in the mixer. The rate of addition of the carbon dioxide is carefully controlled in relation to the operating cycle of the mixer in order that it is added evenly and is allowed to contact all the surfaces of the pieces of meat. The very low temperature of the carbon dioxide "snow" causes the meat mixture rapidly to cool. 30 seconds to 1 minute after the introduction of the carbon dioxide the meat mixture as a whole has cooled.Within 10 minutes the mixture reaches a stable temperature of around to and most of the carbon dioxide has been vapourised and dispersed from the mix since its boiling point is much lower than the temperature of the mix. Although the average temperature of the mix is -1 to --4"C as described above, a few pieces may remain at a much lower temperature, perhaps -50"C, during this stage.

5. The frozen meat mixture is removed from the mixer by any conventional conveying method, typically by using an auger drive and transferred to a forming machine. Alternatively the mixture may be collected from the mixer and transferred to the forming machine in a receptacle. When the mixture reaches the forming machine its temperature remains below 0 C but is more uniform throughout the mixture and very cold pieces are now absent.

6. The majority of the pieces of meat in the mix transferred to the forming machine are whole muscle pieces at a low temperature. At this temperature the meat is viscous and the forming machine is able to use pressure to push this cooled, relatively stiff meat into any desired shape determined by mould plates ofvarious sizes and dimensions.

Atypical forming machine can be one which is generally used to mould beefburgers or other shapes from chopped or minced meat mixtures, and includes a hopper into which the meat mixture is delivered. The meat mixture is fed from the hopper on a further auger drive conveyor.into the mouth of a pressure forming cylinder. A mould plate slides transversely in and out of the exit path of the meat mixture from the cylinder. The moulding plate slides forward into the delivery path from the cylinder and the mixture is compressed and pushed into a number of vacant moulds in the mould plate. The mould plate is then retracted to a second position where it aligns with an equal number of rams, which push the shaped meat mixture out of the mould and prepare the mould for repetition of the cycle. The formed and shaped meat product remains stable and may be removed for further processing by, for example, coating with batter and breadcrumbs, or may be packaged directly.

The meat product may be formed in any desired shape and may be moulded in a three-dimensional mould rather than the extrusion process outlined above. In one example irregular shapes having approximate dimensions of 7 cms x 3 cms are produced. Each product comprises perhaps three or fourwhole pieces of meat muscle and a small proportion of minced skin, flavourings etc. It should be noted that the steps of massaging the meat in a salt solution and adding finely minced skin to the meat are not absolutely necessary in the process and may be omitted for certain products if desired.

Claims (9)

1.A A process for manufacturing shaped meat articles comprising the steps of applying a fluid or particulate substance as a refrigerant to foodstuff which includes pieces of meat to freeze the pieces; the substance being such that it disperses from the foodstuff during cooling, and forming shaped articles from the foodstuff; each article bing formed whilst the pieces of meat are at a low temperature such that they are relatively stiff and mouldable and including at least one piece of meat.

2. A process as claimed in claim 1 wherein a fixed volume of foodstuff is agitated inside a vessel at the same time as the refrigerant is added.

3. A process as claimed in claim 1 or claim 2 wherein each article comprises a plurality of meat pieces.

4. A process as claimed in any one ofthe preceding claims wherein the meat pieces are whole chicken muscles.

5. A process as claimed in any one of the preceding claims wherein the foodstuff is formed into shaped articles at an average temperature within the range 0 to -6"C.

6. A process as claimed in any one of the preceding claims wherein the refrigerant is provided at a temperature significantly lower than the eventual temperature of the meat.

7. A process as claimed in claim 6 wherein the refrigerant is carbon dioxide in the solid state at a temperature of about -1 000C.

8. A process as claimed in claim 6 wherein the refrigerant is nitrogen at a temperature of about 100"C.

9. A process for manufacturing shaped meat articles substantially as hereinbefore described.