DE2916266C2 - - Google Patents

Description

The invention relates to a method for Production of a frozen food product according to the preamble of claim 1.

Such a method is known from GB-PS 6 96 049. Before this state of the art is explained in more detail, be For a better understanding of the invention, the following sent.

There are already a considerable number in the market prepared foods available only relatively briefly boiled or otherwise treated to to bring them into a condition suitable for consumption. Such products are generally referred to as "Convenience foods", including cooked or ready-to-eat foods or to understand food and ready meals are.

The well-known foods of this kind can be found in the into three groups, namely conserved, dried and frozen or frozen Products. However, these types of foods are all with Problems and disadvantages attached.

For example, preserved in cans or cans Foods are bulky, and their shelf life hangs alone from a hermetic conclusion. The integrity with Rifle or box is therefore closely related the quality of the product.

Dried foods stand up to theirs Edibility not in high regard. Especially dried Products that have been re-enriched with water, are consumed by the consumer as low quality food  and enjoyment. Here are still many overcome technological problems. One already has numerous attempts have been made to improve the castability, the taste and structure of dried foods by getting the denaturing effects by heat and by the concentration of dissolved substances decreased. Although in the lab with certain products certain successes have been achieved, there are great difficulties on when the laboratory results come into commercial practice to be implemented.

Although the proportion of frozen or frozen Food has grown significantly in the last fifteen years especially in the last five years Years, indicating the increased use of freezers or freezers in private households is, is also with this kind of food the preparation associated with difficulties.

The current supply of frozen foods can be divided into three groups:

• (1) Uncooked frozen ready meals, for example blanched vegetables, fish fingers and beefburger, in front not to be thawed during cooking or preparation need. The advantage of Nichtauftauens, however With it bought that food in small pieces must be present or an artificially induced large Surface, such as food in the cooking bag. The cooking or preparation time of these foods is generally 5 to 25 minutes.
• (2) Uncooked frozen foods in one piece, for example frozen chicken or frozen meat. These foods must be prepared before cooking or before preparation be thawed. As a result, the entire Preparation time more than 24 h.  
• (3) Cooked ready-to-eat foods, for example frozen whole meals and fried meat slices. These foods must be in a conventional Stove for more than 10 min or in another expensive Device, for example a microwave oven, to be heated.

All these foods have one thing in common Main disadvantage, namely costly thawing and or or or Cooking or preparing to make it suitable for human consumption To bring state.

Apart from the use of freezing for preservation From foods it is also known to freeze for the concentration of products or products consulted. This can be done while freezing a liquid Product formed ice cream to be removed from the product For example, from a fruit juice, which is a product with a lower moisture or water content, which was later restored to its original form can be. In extreme cases, most of the Ice removed in a vacuum. This process will freeze-dry called. This produces products such as instant coffee or Instant coffee enriched with water can be. An essential limitation of the freeze concentration method is to be seen in that this Operation can only be applied to liquids. Freeze-drying on the other hand can be both solid and used in liquid foods. They are only stable under certain environmental conditions. Although she can be quickly restored, these products have no acceptable taste and no acceptable Structure or texture, although they contain solid pieces.  

From the aforementioned GB-PS 6 96 049 it is in the Production of a frozen food product known, to reduce the moisture content before freezing, to burst or break the cell structure of the frozen one To avoid product. Furthermore, this can partially dehydrated product impregnated in a solution before freezing which are flavorings, dyes and the like contains.

From GB-PS 14 11 926 is a method for manufacturing a food product known in which one the food likewise adjusted to a moisture content, which is below the normal value of the food. The product is before or during the adjustment of the moisture content at least with a physiologically acceptable salt added, wherein the total salt content does not exceed 10 wt .-%.

From CA-PS 9 79 719 is a frozen soup concentrate known, the water and water-insoluble food substances contains. In addition, it contains water-soluble Substances, such as salts, in an amount of about 20 to 40% by weight (relative to the frozen product). By adding the water-soluble substances ensures that the soup concentrate for example, despite its frozen state Can be easily portioned by means of a spoon. For preparation The portioned frozen soup concentrate comes with diluted in hot water.

The object of the invention is to provide a method of the generic type Form such a way that the produced frozen food product quickly and easily into one can be brought to a suitable state for consumption, namely with acceptable or advantageous organoleptic properties.  

This object is achieved by the subject matter of the claim 1 solved.

The method according to the invention manufactured product for human consumption or intended for the nutrition of animals, thereby becomes the consumption prepared that hot or hot water in such a Amount added is the moisture content of the Brings the product to about normal, while at the same time the product to a suitable normal temperature for consumption is raised.

The salt used is preferably sodium chloride.

The moisture content of the food advantageously becomes to a value of 30 to 80%, preferably 40 to 55% of the original moisture content of the raw Food diminishes.

The humidity setting can be done by that fresh food is removed from water or that dried, preferably powdered foods partially enriched with water. The last given For example, methods can be used to: from structured vegetable protein meaty products to win.

Products made by the process of the invention can feel the flavor and structure of frozen ones Food with the ease of preparation reunite with water-fortified foods. It is possible and highly desirable, both thawing as well as rehydration within a duration of a few seconds, but with certainty within a few minutes.  

To get the best results, you have three consider important circumstances.

First, the frozen nutritional product must be porous or otherwise easily permeable, so that both thawing as well as re-enrichment with water can be done quickly and homogeneously. This can be done by it achieve that you can either use a product with less Particle size or by appropriate treatment larger Produces parts with a suitable structure. An important preferred measure of the invention results from the Discovery that one without prejudice to food chunks or Use food pieces in the product or product can, if achieved by appropriate treatment, that these chunks or pieces also thaw quickly and rehydrate.

Second, the initial moisture content will be adjusted so that, if an appropriate amount of water higher temperature is added to the frozen product, to bring it to eating temperature, the moisture content of the final product assumes about a value that in the can not expect frozen product. This condition is neither concerned with the thawing / rehydration process the realtiven quantity still the temperature of the added Water a predetermined limit. These two Circumstances depend entirely on the nature of the product. A product based on meat can go to one be brought to such a formula that it is at a temperature from 20 to 40 ° C is suitable for consumption by animals, or by decreasing its initial water content, increasing the volume of added water or raising the temperature the added liquid for digestion by man at 50 to 70 ° C is suitable. Important is thus the added total amount of heat (water temperature × water volume).  

Third, a portion of the product Water should remain unfrozen. This amount is going through controlling the water-soluble salt components of the product. The aqueous phase is in contact with ice at equilibrium standing solution from a given dissolved Fabric always has the same concentration. The bigger the The amount of added salt is what it normally is is sodium chloride, the greater is the Amount of water you need to get at a given Temperature below freezing to dissolve the salt, and therefore remains unfrozen. The control of the crowd Frozen water is up to the final temperature of the product critical, because compared to the specific heat of the water of 1 Cal / g the latent heat to melt of ice is 80 cal / g. The added water is thus, melting one gram of ice 80 times more heat withdrawn as to raise the temperature of a gram of molten ice is required by 1 °. The eating temperature of the product can therefore be compared with the ratio of frozen to control non-frozen water in the product. It is possible to have a relationship between the water content, the content of soluble solids and the amount and Temperature of the added water for the product too calculate the desired eating temperature and concentration results.

For example, if the frozen product consists of a gram of unfrozen water (containing a small amount of soluble solid food ingredients), b grams of frozen water and c grams of solid food materials and has a temperature of -K ° C and if the temperature of the frozen product is at a consumed temperature should be raised from + P ° C and the final moisture content of W % by addition of d grams of water with an initial temperature of + T ° C is to be achieved and in addition pulls out into range that the specific heat of water is 1 , that of ice is 0.3 and that of the solid food is 0.8 and that the latent heat of fusion of ice is 80 cal / g, the following applies:

a (K + P) + b (0.3 K + 80 + P) + 0.8 c (K + P) = d (T - P) (1)

and

Assuming that the final restored Product contain 1% sodium chloride (a typical value) should, by the salt content of the frozen product is provided, and considering that the concentration the sodium chloride solution in equilibrium with ice at -20 ° C is about 20%, the following applies:

a = 0.04 (a + b + c + d) (3)

If you express the result in percent, you get the following relationship:

a + b + c = 100 (4)

As an example of the application of these equations a pet food, which at -20 ° C is stored and when reconstituted with boiling Water to a moisture content of 80% and a salt content of 1% at a consumption temperature of 30 ° C, provide the above equations the following values:

Frozen product: Solid food substances 41.5% Frozen water 47.9% Unfrozen water 8.5% salt 2.1% rehydration: @ Frozen product from -20 ° C 100 parts Water of 100 ° C 111 parts

Instead of sodium chloride, you can also use other salts use. To achieve an equivalent anti-freezing effect however, the required salt weight is generally higher. Instead of sodium chloride or in addition of sodium chloride For example, you can use monosodium glutamate add to the intensification of the taste. The addition amount any single salt is 0.5 to 4 wt .-%, but especially 0.5 to 2.5 wt .-% of the frozen Product and is generally of the order of magnitude at 2% by weight.

The production of a nutritional product according to the invention It requires that the moisture content of a food before freezing. The reduction of the moisture content can be achieved (a) by drying or (b) by stripping or draining of liquid or juice. These different procedures should be explained by the following examples:

• (a) For meat with a normal moisture content (75-80%) the meat is heated until sufficient a lot of moisture has been removed to one Moisture content of 45 to 50% to arrive. To freezing is achieved by restoring that, if you just the original product would like to add a lot of water, the is equivalent to the evaporated amount of water, or, for example, if you add an extra amount Would like to have sauce, adding a larger amount of water.

A similar result can be achieved by that of a dried or hydrated material starting with a fibrous structure, for example of structured vegetable protein (TVP) or dried Meat. This material is then partially rehydrated (to 35 to 60 wt .-% H₂O), with water, which contains a water-soluble salt. This happens before  freezing. The fibrous structure and inclusion of water-soluble salt component contained within the pieces leads to a proportion of non-frozen water Surprisingly, a combination effect in which result in pieces of food that are in contact with Thaw hot water within seconds and again hydrate. In a preferred embodiment This will be partial rehydration with liquids or juices made from the meat components of the product were cooked in which then the appropriate amount of salt was dissolved. For pieces that too are dry, the re-enrichment occurs with water or Rehydration only slowly. When the pieces are too are wet or contain no added salt happens thawing is not uniform. For larger amounts of salt The process is sufficiently adequate from a technical point of view good, but the taste of the final product is insufficient.

As an alternative to partially drying a nutritional product by evaporation of water it is possible to achieve a similar result in that the nutritional product brought into contact with an absorbent which is the nutritional product required Extracts amount of moisture. This procedure can be for example, apply when the nutritional product for should not be heated for a long time. A heating for a longer period of time is ever necessary if the required amount of water from the nutritional product wants to evaporate.

• (b) After the meat has been cooked, you can surplus to the desired moisture content Amount of liquid or juice from the solid Derive or squeeze out food substances. The Liquid can be excreted in a dry material or absorbed by a dry material, and Although in such a way that the moisture content  of the dry material to the same value as that of the squeezed or dehydrated meat increases.

To restore or restore the invention Nutritional products, d. H. to transfer the Products in a condition suitable for consumption, one must Add an amount of liquid to the product on a Temperature and to bring a moisture content that suitable for eating. For a predetermined eating temperature you have to increase the amount of added liquid to ± 25% to estimate an acceptable one in the case of meat with sauce To get final product. In a private household you can do not expect the amount of liquid added to the product is exactly balanced.

A convenient way to measure the required amount of addition to liquid according to the invention is that the material is placed in a jar and then straight is covered with the rehydrated liquid. These conditions can be estimated very easily with the eye. For reasons of convenience, you can the bulk density of the product according to the amount of liquid change, which is required to a special final temperature and to get final analysis. Although there are other ways to Measuring the amount of rehydrating liquid, The explained method appears to be the most convenient.

The bulk density of the product can be in different Change or control way:

• (1) The pre-frozen product can be at the correct density be pressed before it is frozen.
• (2) Other raw materials of suitable bulk density can be added to adjust the total density.  
• (3) The material can be mechanically processed to reduce the density before it is frozen, for example by emulsification or foaming.
• (4) The material can be treated mechanically if it freezes, for example, by whipping and float or hitting.
• (5) The material can be mechanically treated after freezing will be, for example, by grinding to be Reduce bulk density.

The following embodiments of the invention are intended merely as examples for explanation. All information in parts and percentages are by weight, unless otherwise stated.

Example 1 animal feed

Meat was cut with the aid of a 1 cm chopping board chopped and cooked at a temperature of 100 ° C for 10 min. When heated, meat juice was made from the meat cooked. The meat was then separated from the liquid and squeezed to remove more liquid, so that then the moisture content of the squeezed meat about 50 to 60% was.

95.2 parts of the squeezed meat were combined with 2 parts of salt, 2 parts of carboxymethylcellulose (CMC) and 0.8 parts of caramel chopped. The ingredients became firm a bulk density of about 0.5 g / ml and compressed then at a temperature of -20 ° C in a household freezer frozen.

If you give the frozen product a sufficient amount added to boiling water that just covered the product, it was thawed and rehydrated within 30 s, where one has a final temperature of 33 ° C and a moisture content of 75%. The restored product existed made of meat in thick sauce and had a shiny appearance. It has been widely accepted by cats and dogs.  

example 2 animal feed

Cooked minced meat was as in Example 1 recycled and squeezed to excess To remove liquids. 93.2 parts of the resulting Mass was pregelatinized with 2 parts salt, 4 parts Starch (Instant Cleargel - Trademark), and 0.8 parts of caramel mixed. This mixture was as in Example 1 treated.

In the re-enrichment with water in the form of boiling water, which just covered the frozen product, This recipe resulted in an end product with thick sauce of shiny appearance at a temperature of 30 ° C.

example 3 animal feed

Compressed meat became as in Example 1 edited. Of these, 95.8 parts were mixed with 2 parts of salt, 0.8 parts caramel, 0.6 parts xanthan gum and 0.8 parts caramel mixed. This mixture was further treated as in Example 1.

After rehydration with boiling water the thickening to a sauce slower than the Examples 1 and 2, but received within one minute a remade product in the form of a shiny one Gels at a temperature of 30 ° C.

example 4 animal feed

Pressed meat was processed as in Example 1. Of these, 92.2 parts were mixed with 4 parts alginate (Manugel GHB - Trademark), 1 part dicalcium phosphate, 2 parts salt and 0.8 parts of caramel mixed. The mixture became as in Example 1 frozen. After the restoration as in example 1 gave a final product in the form of a stump looking gels.  

example 5 animal feed

In this example, a gelling agent was a crude pectinhaltiges material (citrus peel) used, whose Pectin content up to a degree of esterification of less when 20% (treated peel) was deesterified.

Compressed meat became as in Example 1 edited. Of these, 92.2 parts were treated with 4 parts of the Peel, 1 part dicalcium phosphate, 2 parts salt and 0.8 parts caramel mixed. The mixture was as in Example 1 frozen. After the restoration as in Example 1 gave a final product in the form of a stump looking gels.

These first five examples were cooked Liquids deprived of meat. To this valuable To store byproduct, you can to the withdrawal of Moisture from the meat an alternative method use.

Examples 6 to 10 animal feed

Meat was chopped with a 1 cm chopping board and brought to a temperature of 100 ° C until the most of the liquid extracted from the meat had disappeared. The meat was then on a bowl placed in an air oven heated to 100 ° C. It was left in this oven or stove until the moisture content had decreased to about 50%. In this process were the water-soluble components of the liquid in the Meat kept and only the actual moisture content reduced.

The meat dried in this way can then be in exactly the same way as the compressed meat of the Examples 1 to 5 are treated (Examples 6 to 10 in Table I) to give equally acceptable end products.  

Table I

Instead of the moisture content by evaporation There is an alternative in reducing dry ingredients added, which reduce the total moisture content, as in the following examples 11 and 12 is executed.

example 11 animal feed

Meat waste of the kind explained above was used for Cooked at 100 ° C for 10 min or heated to 100 ° C for 10 min. Then it was the meat with the boiled liquid or the boiled juice which has a low moisture content added ingredients to the total moisture content to reduce to 50%. A suitable Recipe is as follows:  

minced meat 55 parts potato protein 5 parts Biscuit 5 parts vegetable protein 5 parts Dry greaves 10 parts Meat and bone meal 5 parts NaCl 2 parts tallow 3 parts caramel 0.1 parts xanthan 0.6 parts carob 0.8 parts Dried decolourised blood 8.5 parts

The mixture should be stirred during freezing be ground or ground after freezing to training to avoid solid frozen pieces that are not thaw easily.

example 12 animal feed

Meat waste was heated as in Example 1, and the cooked meat juice was stored. 87 parts this meat juice was mixed with 13 parts wheat flour, and the resulting dough was dried by rolling and then ground to powder. This way will the liquid or the juice together with its taste and nutritional value, and at the same time become the starches gelled in the flour so that it is not necessary to add a pregelatinized starch.

According to the final recipe were in this example 78.8 parts of the heated compressed meat with 19 parts of the dried by rolling dough from the Flour and the boiled liquid, 2 parts salt and 0.2 parts of caramel mixed. This mixture was in a Frozen in Example 1 way.  

Other suitable binders for the cooked Juice that is added by rolling before drying can, are soybean meal and gluten. However, that is Addition of a gelling agent is desirable when using these ingredients be used.

A particularly preferred embodiment of Invention is based on that cooked or squeezed out Meat sauce is used to be structured Partially rehydrate plant protein. To reference is made to the following example.

example 13 animal feed

Meat waste was cooked as in Example 1 or heated and then squeezed. In the meat juice were Salt and caramel dissolved. An equal amount by weight dried structured vegetable protein became the liquid or added to the juice. The whole thing was touched, until the structured vegetable protein absorbs the liquid would have. The partially rehydrated structured Plant protein was then compressed with the Meat mixed. The added amounts of salt and caramel were chosen so that in the frozen product Concentrations of 2% and 0.8%, respectively.

The mixture can then be frozen as in Example 1 become. Thawing and rehydratization preserves a lumpy product of good looks. The meat juice is made from the structured vegetable protein by the Extracted liquid added to thaw the product becomes. If it is desired to make a sauce, can the compressed meat and the textured Vegetable protein are coated with a thickening agent, as was the case in Examples 1 to 5, and although by simply stirring in a powder mixture these thickeners.  

It is also possible to use the technologies of the examples 12 and 13 to combine. For this, see the following example directed.

example 14 animal feed

In this example, part of the extruded Meat juice for the production of the structured vegetable protein used. A recipe for a vegetable protein dough as follows.

juice 30 parts Defatted soy flour 36 parts Corn meal 10 parts sulfur 0.02 parts

This dough is made from a cooking extruder at 150 ° C extruded. After cooling, the resulting structured vegetable protein combined with the rest of the juice, partially hydrated structured To provide vegetable protein, as in Example 13 can be used.

The teaching of the invention is not on the production limited to animal feed. It is equally possible Produce foods for human consumption are determined. For this, see the following example made aware.

example 15 Food for humans

Stewed steak meat was made using a 1 cm chopping board chopped and then held at 100 ° C for 10 min. Out The treated meat was as in Example 1 of the Squeezed out juice. This meat juice was as in Example 13 Added salt and caramel. The resulting liquid was then used to structured vegetable protein (Bontrae 7240 - Trademark) partially hydrate again. Subsequently, the product became as in Example 13  treated. After rehydration the product had a pleasant meaty smell and a look like Chow Mein, because of the structure of the structured Vegetable protein. Because Bontrae is a good absorbent Embodiment of structured vegetable protein you can add a larger amount of hot juice, so that the Eßtemperatur is close to 70 to 80 ° C without an excess of gravy occurs.

Claims (3)

A process for producing a frozen food product which comprises adjusting a food (mixture) to a moisture content lower than the normal value of the food (s), to the food (mixture) before, during or after the adjustment of the moisture content physiologically compatible substance is frozen and the substance provided, low-moisture food (mixture) is frozen, characterized in that as a substrate at least one water-soluble salt is added, each salt in an amount of 0.5 to 4 wt .-% ( based on the frozen product), wherein in the case of the addition of more than one salt, the total salt content of 10 wt .-% (based on the frozen product) is not exceeded. 2. The method according to claim 1, characterized, that is used as salt sodium chloride. 3. The method according to claim 1, characterized, that the moisture content of the food (mixture) on a value of 30 to 80%, preferably 40 to 55% of the original Moisture content of raw food is reduced.