GB2356123A - Seperately cooking egg white and egg yolk - Google Patents

Abstract

A method for preparing cooked egg comprises placing separated egg white or yolk in a container and sealing it, cooking the white or yolk to a maximum temperature then cooling and removing the cooked product. The maximum temperature may be 80-110{C, preferably 85-91{C and the cooking time may be up to 10 minutes, e.g. 2-3 minutes. The temperature of the product may be 0-10{C, e.g. no less than 2{C during cooling. The container may be partly evacuated prior to sealing to prevent aeration of the white or yolk during cooking. The white or yolk may be allowed to stand prior to cooking in order to stabilise. The product may be cuboidal in shape and the container may comprise a flexible, sealable pouch e.g. a flat bag 20 with a volume of 1000-5000 ml e.g. 2000-2500 ml. Up to 5 kg of uncooked white or yolk e.g. 2.5 kg may be placed in the container. Cooking may comprise steaming, and the temperature of the steam cooker may rise gradually to the maximum temperature. Up to six containers may be laid flat on a slatted/perforated/wire tray in the cooker and a trolley may hold up to ten trays. The cooked white or yolk may be chopped, diced, comminuted, ground or milled to a paste then combined with the other of the white or yolk in the desired proportions. A mixture of chopped cooked egg white and ground egg yolk and a sealed, partly evacuated container containing egg white or yolk is also disclosed.

Description

2356123 NOVEL COOKED EGG PRODUCT AND PROCESS FOR PREPARING THE SAME The

present invention relates to a novel cooked egg product. The invention also provides a process for preparing a cooked egg product. Mixtures of chopped or diced cooked egg are used in a variety of foods, typically in sandwich fillings, salads and the like. Conventionally, such 10 mixtures are prepared by cooking whole eggs in boiling water, shelling the cooked eggs, and chopping or dicing the eggs to yield a chopped mix of cooked egg white and cooked egg yolk. A disadvantage of this method is that the proportion of egg white to egg 15 yolk in the chopped mixture will depend on the constituents of each cooked egg that is chopped into the mixture, and hence cannot conveniently be regulated during preparation of the mixture. Thus, for example, a mixture having a lower overall proportion of egg white to egg yolk than is naturally found in eggs cannot easily be prepared by this method. Moreover, owing to 20 the difficulty of dicing an ellipsoidal egg into uniform parts, a chopped cooked egg mixture prepared in accordance with the conventional method will comprise irregularly sized diced egg portions. If a more uniform mixture is required, substantial wastage of cooked egg will be inevitable. 25 It is an object of the present invention to provide an improved method of preparing cooked egg, with a view, in particular, to the preparation of chopped cooked egg mixtures. According to the present invention, therefore, there is provided a method for 30 prepaning cooked egg, comprising the steps of providing separated uncooked 2 egg white or separated uncooked egg yolk, placing said egg white or egg yolk into a container, sealing said container, cooking said egg white or egg yolk to a pre-determined maximum temperature, cooling said egg white or egg yolk, and removing the cooked egg white or egg yolk from the container.

In another aspect of the present invention, there is provided cooked egg white and/or cooked egg yolk prepared in accordance with the method of the present invention.

In yet another aspect of the present invention, there is provided a sealed, partly evacuated container, containing separated uncooked egg white or separated uncooked egg yolk, for steaming or boiling.

Preferably, said uncooked egg white or uncooked egg yolk is pasteurised. Up to 5kg of uncooked egg white or uncooked egg yolk, preferably 2-3kg, most preferably about 2.5kg of uncooked egg white or uncooked egg yolk, may be placed in said container. Selected flavourings, colourings, additives, seasonings, preservatives, or other ingredients may be added to said 20 container prior to sealing, and mixed with said egg white or egg yolk, for example by stirring or agitation. The volume of said container may be 1-5L, preferably about 2-2.5L. The configuration of said container may be such that said uncooked egg white or 25 uncooked egg yolk will cook within said container into a substantially cuboidal block of cooked egg product. Said container may comprise a flexible sealable pouch, such as a formed flat sealable bag. Preferably, said pouch is formed from a food-grade plastics 30 material. Advantageously, said uncooked egg white or uncooked egg yolk 3 may be dispensed into said pouch on a special form filling machine, such as a Tiromat form filling machine. In a particular aspect of the invention, the pouch may be substantially filled with uncooked egg white or yolk, such that the pouch fills out and the egg substantially conforms to the shape of the pouch, whilst allowing for some expansion of the contents of the pouch on cooking.

Said container may be partly evacuated prior to sealing to prevent or at least reduce aeration of the egg product during cooking.

Advantageously, said uncooked egg white or uncooked egg yolk may be allowed to stand in said container for a period of time prior to cooking, such that said uncooked egg white or uncooked egg yolk is enabled to stabilise.

This will ensure a uniform consistency and thickness in the final cooked product.

Said cooking may comprise steaming or boiling. In a preferred aspect of the present invention, said cooking comprises steaming in a steam cooker.

Advantageously, one or more slatted or perforated or wire trays may be provided, and said container may be placed on such a tray for steaming in said steam cooker. Said container will preferably be laid flat on said tray, so as to ensure uniform cooking of the product contained in the container.

Preferably, a plurality of containers, typically up to six containers, may be placed or laid flat on a tray for simultaneous steaming in said steam cooker in accordance with the present invention. Advantageously, one or more trolleys may be provided for entering said trays into said steam cooker.

Preferably, each of said trolleys may be adapted to be simultaneously loaded with up to ten trays.

Said pre-determined maximum temperature will typically be of the order of 4 80-11 O'C, preferably 85-9 VC, so as to ensure a thoroughly cooked but not over-cooked end product. Where a long product shelf life and/or a hard end product consistency is required, said pre-determined maximum temperature may exceed 91T. In selecting said pre-determined maximum temperature, the skilled man will take into account factors such as the final use and desired shelf life of the end product.

Preferably, the ambient temperature of said steam cooker is raised gradually during cooking up to said pre-determined maximum temperature. For convenience, steam may be produced in said steam cooker or entered into said steam cooker under the control of a programmable controller or RLD, loop. Said programmable controller or RID loop may be programmed with a predetermined temperature ramp rate, so as to enable a gradual controlled increase in the ambient temperature of said steam cooker during cooking.

To enable proper regulation of the cooking process, the temperature of said egg white or egg yolk may be directly or indirectly monitored during cooking. In one embodiment of the present invention, where at least two filled containers are cooked simultaneously, one container may be designated a "control container", and a temperature probe may be inserted into said control container for monitoring the temperature of the egg product therein.

Preferably, the ambient temperature of said steam cooker is controlled during cooking to ensure that said ambient temperature and the temperature of the egg product within said control container remain approximately equal during cooking.

Advantageously, said egg white or egg yolk is kept at said pre-determined maximum temperature for a pre-determined period of cooking time. The length of said pre-determined period of cooking time will be selected by the skilled man taking into account factors such as the final use and desired shelf life of the end product. Where a soft product consistency is desired, the length of said pre-determined period of cooking time may be of the order of 2-3 minutes. Where a harder product consistency and/or a long product shelf life is desired, the length of said pre-determined period of cooking time may be of the order of up to 10 minutes or more.

Said cooling may comprise rapid chilling or blast chilling. Preferably, the temperature of said egg white or egg yolk is reduced to 0-10T, more preferably 0-5'C, most preferably about 2'C, during cooling.

After cooking, the cooked egg white or cooked egg yolk may be discharged in a block from said container. Optionally, said cooked egg white or cooked egg yolk may be mechanically divided, preferably chopped or diced. It will be appreciated that where the block of cooked egg white or cooked egg yolk has a cuboidal or substantially cuboidal shape, said block may be chopped or diced into uniformly sized portions with minimal wastage. For some recipes, the cooked egg may be mechanically comminuted or ground to a paste. In particular, in order to confer upon the cooked egg yolk the crumbly, smooth texture of conventional shell-cooked egg yolk, said cooked egg yolk may be ground or milled to a fine wet paste. Said cooked egg yolk may be ground or milled using an Urschel Comitrol 3600 (Urschel Laboratories international Ltd, Tiber Way, Meridian Business Park, Leicester). Alternatively, a bowl chopper may be used for fine grinding of the cooked egg yolk.

In a particularly preferred embodiment of the present invention, there is provided a method for preparing a mixture of chopped cooked egg white and ground cooked egg yolk, comprising the steps of preparing cooked egg white in accordance with the present invention, preparing cooked egg yolk in accordance with the present invention, chopping said cooked egg white, grinding said cooked egg yolk to a paste, and mixing said chopped cooked 6 egg white and said ground cooked egg yolk in the proportions desired. There is furthermore provided a mix of chopped cooked egg white and ground cooked egg yolk, prepared in accordance with said method.

The method of the present invention may be employed on a commercial scale in the preparation of cooked egg white and/or cooked egg yolk, and/or mixes of chopped cooked egg white and ground cooked egg yolk. Following is a description, by way of example only and with reference to 10 the accompanying drawings, of embodiments of the present invention and methods for putting the present invention into effect. In the drawings: 15 Figure I shows a front view of a sealed pouch 10 containing uncooked egg white. Figure 2 shows a front view of a pouch 10 containing cooked egg white. 20 Figure 3 shows a front view of a sealed pouch 20 containing uncooked egg yolk. Figure 4 shows a front view of a pouch 20 containing cooked egg yolk. 25 Figure 5 shows a side elevation of three pouches 30 containing cooked egg, Example 1: Preparation of cooked egg white 30 A pouch (10) containing cooked egg white prepared in accordance with

7 present invention is shown in Figure 2. In the preparation of this product, a plurality of eggs are first separated in the conventional manner to obtain uncooked egg white. The uncooked egg white is pasteurised in accordance with methods known to the man skilled in the art, and is dispensed by a Tiromat form filling machine into formed sealable pouches. Each pouch is made from a food-grade plastics material, and has a capacity of 2 - 2.5L.

Approximately 2.5kg of egg white is dispensed into each pouch by the form filling machine, giving a depth of about 20min egg white within each pouch (10), as shown in Figure 1. Selected flavourings, colourings, spices, condiments, stabilisers, preservatives, or other ingredients or additives are also dispensed into the pouch, and are dispersed in the egg white by stirring or agitation. The pouch is then partially evacuated and -sealed, in accordance with methods familiar in the art.

Up to six charged pouches are laid flat on a perforated tray, and the tray is loaded onto a trolley which is adapted to hold up to ten trays. The loaded trolley is entered into a steam cooker such as a SiMan steam cooker. Once in place inside the steam cooker, the loaded trolley is allowed to stand still for a period, in order to allow the uncooked egg white contained in each pouch to stabilise prior to cooking, so that an even thickness and product consistency may be attained in the cooked product. One pouch is selected as a "control pouch", and a temperature probe is inserted into said control pouch, for monitoring the temperature of the egg white therein.

The steam cooker is fitted with a programmable controller or P.I.D. loop of the kind known in the art, which acts to regulate the ambient temperature of the steam cooker by controlling the entry of steam into the interior of the cooker. Said programmable controller or P.I.D. loop is connected to said temperature probe, and is programmed in accordance with known methods with a pre-determined temperature profile. The programmable controller or 8 PID. loop thus acts to ensure that the ambient temperature of the steam cooker will increase gradually to a pre-determined maximum temperature, whilst the difference between the ambient temperature of the steam cooker and the temperature of the egg product within the control pouch remains at a minimum. Typically, the pre-determined maximum temperature will be between 85 and 91'C. As will be appreciated by the man skilled in the art, however, the pre-determined maximum temperature may be selected to yield cooked egg white with the desired consistency and/or shelf life. Where a hard consistency and/or a long product shelf life is desired, for example, a pre-determined maximum temperature of over 91'C may be used.

Once the ambient temperature of the steam cooker has reached said pre determined maximum temperature, the programmable controller or PID.

loop acts to prevent the ambient temperature from increasing further, and to maintain the ambient temperature at its pre-determined maximum. The egg white is maintained at this temperature for a pre-determined period of cooking time, typically between 2 and 10 minutes in length. As will be appreciated by the man skilled in the art, the product cooking time may be selected to yield a cooked -product with the desired consistency and/or shelf life. A longer cooking time, for example, will yield a product with a harder consistency and a longer shelf life.

After cooking, the loaded trolleys are withdrawn from the steam cooker, and the pouches are placed in a blast chill to bring the temperature of the cooked egg white within each pouch down to a level of approximately 0-5C, typically about 2C. The cooked egg white in each pouch is discharged from the pouch, yielding a solid substantially cuboidal block of cooked egg white, typically about 380mm x 280mm x 20mm in dimension, as illustrated in Figure 2.

9 Example 2: Preparation of cooked egg yolk A pouch (20) containing cooked egg yolk prepared in accordance with the present invention is shown in Figure 4. In the preparation of this product, a plurality of eggs are first separated in the conventional manner to obtain uncooked egg yolk. The uncooked egg yolk is pasteurised in accordance with methods known to the man skilled in the art, and is dispensed by a Tiromat form filling machine into formed sealable pouches. Each pouch is made from a food-grade plastics material, and has a capacity of 2 - 2.5L.

Approximately 2.5kg of egg yolk is dispensed into each pouch by the form filling machine, giving a depth of about 20mm egg yolk within each pouch (20), as shown in Figure 3. Selected flavourings, colourings, spices, condiments, stabilisers, preservatives, or other ingredients or additives are also dispensed into the pouch, and are dispersed in the egg yolk by stirring or agitation. The pouch is then partially evacuated and sealed, in accordance with methods familiar in the art.

Up to six charged pouches are laid flat on a perforated tray, and the tray is loaded onto a trolley which is adapted to hold up to ten trays. The loaded trolley is entered into a steam cooker such as a SdMan steam cooker. Once in place inside the steam cooker, the loaded trolley is allowed to stand still for a period, in order to allow the uncooked egg yolk contained in each pouch to stabilise prior to cooking, so that an even thickness and product consistency may be attained in the cooked product. One pouch is selected as a "control pouch", and a temperature probe is inserted into said control pouch, for monitoring the temperature of the egg yolk therein.

The steam cooker is fitted with a programmable controller or PID. loop of the kind known in the art, which acts to regulate the ambient temperature of the steam cooker by controlling the entry of steam into the interior of the cooker. Said programmable controller or P.I.D. loop is connected to said temperature probe, and is programmed in accordance with known methods with a pre-determined temperature profile. The programmable controller or PID. loop thus acts to ensure that the ambient temperature of the steam cooker will increase gradually to a pre-determined maximum temperature, whilst the difference between the ambient temperature of the steam cooker and the temperature of the egg product within the control pouch remains at a minimum. Typically, the pre-determined maximum temperature will be between 85 and 91T. As will be appreciated by the man skilled in the art, however, the pre-determined maximum temperature may be selected to yield cooked egg yolk with the desired consistency and/or shelf life. Where a hard consistency and/or a long product shelf life is desired, for example, a pre determined maximum temperature of over 91'C may be used.

Once the ambient temperature of the steam cooker has reached said pre determined maximum temperature, the programmable controller or PID.

loop acts to prevent the ambient temperature from increasing further, and to maintain the ambient temperature at its pre-determined maximum. The egg yolk is maintained at this temperature for a pre-determined period of cooking time, typically between 2 and 10 minutes in length. As will be appreciated by the man skilled in the art, the product cooking time may be selected to yield a cooked product with the desired consistency and/or shelf life. A longer cooking time, for example, will yield a product with a harder consistency and a longer shelf life.

After cooking, the loaded trolleys are withdrawn from the steam cooker, and the pouches are placed in a blast chill to bring the temperature of the cooked egg yolk within each pouch down to a level of approximately 0-5'C, typically about 2'C. The cooked egg yolk in each pouch is discharged from the pouch, yielding a solid substantially cuboidal block of cooked egg yolk, typically about 380mm x 280mm x 20mm in dimension, as illustrated in Figure 4.

Example 3: Preparation of a cooked egg mixture Blocks of cooked egg white and cooked egg yolk, as shown in Figure 5, are prepared as described in Examples I and 2 above. The blocks of cooked egg white are chopped into portions of a selected size. Meanwhile the blocks of cooked egg yolk are ground to a fine wet paste using an Urschel Comitrol 3600 (Urschel Laboratories International Ltd, Tiber Way, Meridian Business Park, Leicester), or a bowl chopper. The resulting portions of chopped cooked egg white and ground cooked egg yolk are mixed in the desired proportion, to yield a mixture of cooked egg. This mixture may be used in a variety of food products, including sandwich fillings and salads.

Claims (16)

12 CLAIMS

A method for preparing cooked egg, comprising the steps of providing separated uncooked egg white or separated uncooked egg yolk, placing said egg white or egg yolk into a container, sealing said container, cooking said egg white or egg yolk to a pre-determined maximum temperature, cooling said egg white or egg yolk, and removing the cooked egg white or egg yolk from the container.

2 A method as claimed in claim 1, charactenised in that the temperature of said egg white or egg yolk is reduced to 0-10T, more preferably 0-5T, most preferably no less than 2T, during cooling.

3 A method as claimed in claim I or claim 2, characterised in that said container is partly evacuated prior to sealing to prevent or at least reduce aeration of the egg product during cooking.

4 A method as claimed in any preceding claim, wherein said uncooked egg white or uncooked egg yolk is allowed to stand in said container for a period of time prior to cooking, such that said uncooked egg white or uncooked egg yolk is allowed to stabilise.

A method as claimed in any preceding claim, wherein the shape of said container is such that said uncooked egg white or uncooked egg yolk will cook within said container into a substantially cuboidal block of cooked egg product.

6 A method as claimed in any preceding claim, wherein said container comprises a flexible sealable pouch, such as a formed flat sealable bag.

13

7 A method as claimed in any preceding claim, wherein up to 5kg of uncooked ego, white or uncooked egg yolk, preferably 2-3kg, most preferably about 2.5kg of uncooked egg white or uncooked egg yolk, is placed in said container.

8 A method as claimed in any preceding claim, wherein the volume of said container is 1000-5000mls, preferably about 2000-2500mls.

9 A method as claimed in any preceding claim, further comprising the step of adding selected flavourings, colourings, additives, seasonings, preservatives, or other ingredients to said container prior to sealing, and mixing said selected flavourings, colourings, additives, seasonings, preservatives or other ingredients with said egg white or egg yolk, for example by stirring or agitation.

A method as claimed in any preceding claim, wherein said cooking comprises steaming in a steam cooker.

11 A method as claimed in claim 10, wherein the ambient temperature of said steam cooker is raised gradually to said predetermined maximum temperature during cooking, such that said ambient temperature and the temperature of the egg product within each container remain approximately equal at all times during cooking.

12 A method as claimed in claim 10 or claim 11, wherein one or more slatted or perforated or wire trays are provided, and said container is placed on one of said trays for steaming in said steam cooker.

13 A method as claimed in claim 12, wherein a plurality of containers, typically up to six containers, are placed or laid flat on each of said trays for 14 simultaneous steaming in said steam cooker.

14 A method as claimed in claim 12 or claim 13, wherein one or more trolleys are provided for entering said trays into said steam cooker. 5

15 A method as claimed in claim 14, wherein each of said trolleys is adapted to be simultaneously loaded with up to ten trays.

16 A method as claimed in any preceding claim, wherein said predetermined maximum temperature is 80-11 OT, preferably 85-9 IT. 17 A method as claimed in any preceding claim, wherein said egg white or egg yolk is kept at said predetermined maximum temperature for up to 10 minutes, preferably 2-3 minutes. 15 18 A method as claimed in any preceding claim, wherein said cooked egg white or cooked egg yolk is discharged from said container and mechanically divided, preferably chopped, diced, comminuted or ground or milled to a paste, after cooking. 20 19 A method for preparing a mixture of chopped cooked egg white and ground cooked egg yolk, comprising the steps of preparing cooked egg white and cooked egg yolk in accordance with the method of any preceding claim, chopping said cooked egg white, grinding said cooked egg yolk to a paste, 25 and mixing said chopped cooked egg white and said ground cooked egg yolk in the proportions desired. 20 A mixture of chopped cooked egg white and ground cooked egg yolk. 30 21 A sealed, partly evacuated container, containing separated uncooked egg white or separated uncooked egg yolk, for steaming or boiling.