JP2013085544A - Freeze-dried food and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a freeze-dried food capable of holding the intrinsic texture and taste which a food material has, and a method for producing the same.SOLUTION: This method for producing the freeze-dried food is provided by heat cooking the pretreated food material by heating with a superheated steam of >100°C, and then vacuum freeze-drying. The freeze-dried food obtained by the method is provided with that the surface of the food is heated at a high temperature and the taste of the food remains at the inside of the food. In this freeze-dried food (1), the presence of a well-heated layer at its surface (a skin layer) (2), and a normally heated part at the inside (3) are revealed on adding hot water.

Description

  The present invention relates to a freeze-dried food, and more particularly to a freeze-dried food that does not lose its original taste by being reconstituted with hot water, and a method for producing the same.

  Freeze-dried foods are widely used as ingredients such as instant noodles, instant miso soup, and instant soup. Among them, seasoned chicken, pork, beef, vegetables, seafood, etc. are often used. These freeze-dried foods have recently been required to have properties such as the original taste, color tone, texture, etc. as well as being genuinely oriented and large-sized.

  In the patent document 1, the applicant of the present invention is a method of vacuum drying or vacuum freeze drying after reducing the moisture in the vegetables by hot-air drying or hot-air drying of the heat-treated and / or sweetened vegetables. is suggesting. Patent Document 2 proposes that the cut onion is dried in advance so that the moisture drying amount is 72 to 89% by weight, and then frozen. Patent Document 3 proposes to produce a drying tool material by subjecting a food material to a superheated steam treatment in a low oxygen state.

  However, the dry food of the conventional method has a problem that the umami of the ingredients disappears and it is difficult to maintain the original texture and umami of the ingredients.

Japanese Patent Laid-Open No. 10-309161 JP-A-7-147892 JP 2000-228970 A

  In order to solve the above-mentioned conventional problems, the present invention provides a freeze-dried food that can retain the original texture and umami of food and a method for producing the same.

  The method for producing a freeze-dried food according to the present invention is characterized in that the pretreated food is cooked by heating with superheated steam exceeding 100 ° C. and then vacuum freeze-dried.

  The freeze-dried food of the present invention is a freeze-dried food obtained by the above-described method for producing freeze-dried food, characterized in that the surface of the food is heated at a high temperature and the umami of the food remains inside the food. To do.

  In the present invention, the pretreated food is cooked by heating with superheated steam exceeding 100 ° C., and then vacuum freeze-dried. Thereby, the freeze-dried food which can hold | maintain the original food texture and deliciousness which a foodstuff has is obtained. Superheated steam exceeding 100 ° C. is a thermal radioactive gas having the ability to emit far infrared rays suitable for heating foods, and therefore has a larger thermal energy than hot air. Therefore, the food can be efficiently heated in a short time, and the umami and the fragrant scent can be kept inside the food. When vacuum freeze-dried in this state, when the freeze-dried food is reconstituted with water, the original texture and taste of the ingredients can be reproduced. Moreover, the superheated steam exceeding 100 ° C. has a sterilizing power, and can be sterilized together with cooking. In the case of a seasoned seasoning, by heating it with superheated steam that exceeds 100 ° C, only the surface is heated at high temperatures without degrading the original flavor and synergistic flavor of the seasoning. Is done. As a result, the internal umami taste is maintained as it is.

FIG. 1 is a cross-sectional view of a food product according to an embodiment of the present invention.

1. Foodstuffs The foodstuffs used in the present invention include meat, seafood, vegetables and the like. Examples of meat include chicken, pork, beef and lamb. Examples of seafood include salmon, salmon, salmon, octopus, and mentaiko. Vegetables include onions, green onions, potatoes, burdock, and corn.

2. Pretreatment The pretreatment referred to in the present invention is at least one selected from cutting a food material into a predetermined size and applying seasoning. The predetermined size is a size of a freeze-dried food suitable for instant foods, and preferred sizes are 2 mm or more in length, width and thickness, more preferably length, width and thickness of 4 mm or more. is there. About length and width, 50 mm or less is preferable, and the upper limit of a preferable thickness is preferably 30 mm or less, and more preferably 20 mm or less. The shape of the food material is arbitrary. Seasoning seasoning means seasoning with seasonings such as soy sauce, salt, sugar, mirin, meat extract, vegetable extract, umami seasoning, edible oils and fats, processed starch, spices, pigments, and antioxidants. The seasoning varies depending on the ingredients and the intended food, but any seasoning may be used.

3. Heating means Meats, vegetables, and seafood are conventionally processed by steaming (steaming machine), baking (baking machine), boiling (boiling machine), and frying (flyer). However, conventional cooking has the following problems.
(1) In the case of steaming, the large-sized ingredients required conditions of about 30 to 60 minutes at 70 to 90 ° C., and there was a problem that the productivity was low and the umami of the ingredients disappeared.
(2) In the case of a baking machine, if the food is not cooked in advance, it takes time until the color of the baking comes out in the baking process, and the shape may be lost, resulting in a problem that the value as a product is lowered. Besides, there was a problem that the umami of the ingredients disappeared.
(3) For the boiled process, a large amount of hot water is required, especially in the case of vegetables, in order to make the color tone vivid, a cooling process is required with cold water, and the taste of the ingredients disappears. there were.
(4) For fried products, a large amount of oil is required in a normal fryer, and when lyophilized, if the product is lyophilized unless it is passed through the step of deoiling in the seasoning liquid soaking step after frying There was a problem that hot water was not restored.
(5) Compared with the heating means, the superheated steam exceeding 100 ° C. used in the present invention is free from the above problems (1) to (4), has good heating efficiency, and efficiently produces food in a short time. There is an advantage that it can be heated and sterilized at the same time, and can be cooked by heating while keeping the taste and fragrance inside the food. Simultaneous sterilization is particularly effective for meat and seafood.

  By heating the pretreated food with superheated steam exceeding 100 ° C., the surface of the food well heated (hereinafter referred to as “skin layer”) and the normally heated part inside It is formed. As a result, the internal umami is maintained as it is by the skin layer. If it demonstrates in drawing, it will become like FIG. 1 and the skin layer 2 and the inside heated part 3 of the inside will be formed in the foodstuff 1 cooked. The thickness of the skin layer 2 is preferably in the range of 0.05 to 2.0 mm, more preferably in the range of 0.1 to 1.0 mm, although it depends on the foodstuff. The skin layer 2 and the normally heated portion 3 in the inside are continuously changing, and the boundary between them may not be clear, and it may occur partially rather than around the food. When returned, it can be determined by the fact that the surface of the food is denser than the inside. The specific thickness of the skin layer can be determined by reconstitution with hot water, cutting, and observing at about 10 times with an optical microscope.

  The temperature of the superheated steam is preferably in the range of 120 ° C to 400 ° C. More preferably, it is 200 degreeC-370 degreeC, More preferably, it is the range of 250-350 degreeC. The time for heating with superheated steam is preferably 1 to 10 minutes, more preferably 2 to 7 minutes, and more preferably 2 to 4 minutes. A short time treatment at a high temperature is preferable for maintaining the internal taste.

4). Drying means There are hot air drying, air drying, vacuum freeze drying and the like as means for drying the food, but there is a problem that the taste of the food disappears by hot air drying. In addition, air drying requires a long time for drying, and there is a problem that bacteria and dust in the air adhere. On the other hand, the vacuum freeze-drying used in the present invention is hygienic and has the advantage that the original taste of the food remains because it can be dried at a low temperature. The degree of vacuum during vacuum freeze-drying is preferably 200 Pascals or less, more preferably 133 Pascals or less, and even more preferably 106 Pascals or less. The product temperature during vacuum freeze-drying is preferably 70 ° C. or lower, more preferably 60 ° C. or lower, more preferably 50 ° C. or lower. Prior to vacuum freeze-drying, so-called preliminary freezing may be performed in which freezing is performed at a temperature of −10 to −45 ° C. for about 10 to 36 hours. The moisture content after lyophilization is preferably 5.0% or less, more preferably 3.0% or less.

5. Reconstitution with hot water The freeze-dried food obtained in the present invention can be eaten with normal reconstitution. That is, as used in instant noodles, instant miso soup, instant soup, etc., hot water is added and immersed for several minutes to return to the state where it can be eaten. Of course, it can be restored even if cooked.

  Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples.

An example of chicken as an ingredient will be described.
Example 1
(1) Seasoning seasoning process Chicken was cut into a 50 mm square and mixed with the seasoning liquid. The seasoning liquid was soy sauce, sugar, mirin, salt, meat extract, umami seasoning, onion powder, edible oil and fat, and antioxidant. In this state, the temperature was set to 5 ° C. and stored for 12 hours. Thereafter, it was frozen at −30 ° C. for 24 hours.

(2) Cut process The frozen food material was diced to 15 mm in length, width, and thickness.

(3) Superheated steam process and sterilization process It heat-processed for 4 minutes using 350 degreeC superheated steam. After that, they were arranged in a tray.

(4) Vacuum freeze-drying process The foodstuff was frozen in -30 degreeC and 20 hours, the vacuum degree was 106 pascals or less, and vacuum freeze-dry was carried out. The water content of the obtained freeze-dried food was 0.5 to 2.0%. The freeze-dried food was packaged for each predetermined weight.
(5) Hot water reconstitution The packaged freeze-dried food was opened, placed in hot water at 90 ° C., held for 3 minutes, and ready for eating. The food in this state had good color and gravy, and the original texture, umami, and fragrant scent of the ingredients were retained. The texture and umami were of good quality that cannot be obtained by conventional methods. Moreover, when the cross section was observed, the thickness of the skin layer was about 0.5 mm.

(Comparative Example 1)
The heating means was changed to the superheated steam of Example 1, and calcination was performed using a gas direct flame. The process is as shown in Table 1. Table 1 shows a comparison with Example 1. When the obtained freeze-dried food was reconstituted in hot water, there was no color luster, no gravy was felt, the original texture, umami and aroma of the ingredients were lost, which is inferior to the product of Example 1 Met.

  As is clear from Table 1, the process of Example 1 does not require the heat coagulation process by steam and the sterilization process by steam treatment after the heat treatment, and the efficiency of the process can be improved. On the other hand, in Comparative Example 1, in the heat coagulation process, when the frozen cut product is passed at the stage of gas direct-fire firing, the frozen product is gradually thawed by the heat of the gas and the shape collapses to generate a drip. Since the product does not adhere to the product, it has been necessary to form and solidify in advance with steam. Next, a process of cutting and passing through a baking process was also necessary. In addition, steam treatment after firing was necessary for sterilization purposes.

(Example 2, comparative example 2)
Take potato fries as an ingredient. The process and prescription are as shown in Table 2.

As is apparent from Table 2, in Example 2, a small amount of edible fats and oils were mixed with potatoes together with the seasoning, and the potato fries could be cooked without using a large amount of edible fats and oils simply by treating with superheated steam. .
The moisture content of the freeze-dried food was 0.8%.

  The packaged freeze-dried food obtained as described above was opened, placed in hot water at 90 ° C., held for 2 minutes, and ready for eating. The food of Example 2 had a crispy surface and a crisp texture inside. Moreover, when the cross section was observed, the thickness of the skin layer was about 0.3 mm. On the other hand, the food of Comparative Example 2 had a mixture of oily and sticky surfaces with oily and sticky insides.

(Example 3, Comparative Example 3)
An example of potato boil cooking is given as an ingredient. The process and prescription are as shown in Table 3.

  As is apparent from Table 3, the preheating / thawing process is unnecessary in Example 3, and the process can be simplified and the production can be efficiently performed. The moisture content of the freeze-dried food was 2.1%.

  The packaged lyophilized food obtained as described above was opened, placed in hot water at 90 ° C., held for 1 minute, and ready for eating. The foodstuff of Example 3 obtained the texture which was like a steamed potato. Moreover, when the cross section was observed, the thickness of the skin layer was about 0.2 mm. On the other hand, the food of Comparative Example 3 had a texture like steamed potato, but many of the shapes were broken.

  Meat and vegetables processed by this production method maintained their shape well even when subjected to heating and pressurizing treatment at 120 ° C. for 10 minutes, and therefore can be used in retort foods.

1 Cooked food 2 Well heated layer (skin layer)
3 Normally heated parts

The method for producing a freeze-dried food according to the present invention is such that the pretreated food is cooked by heating with superheated steam exceeding 100 ° C., and then lyophilized by vacuum lyophilization, whereby a skin layer is formed on the surface. And a freeze-dried food having a skin layer thickness of 0.05 to 2.0 mm is obtained .

The freeze-dried food of the present invention is a freeze-dried food obtained by the above-described method for producing a freeze-dried food, the surface of the food is heated at a high temperature, the taste of the food remains in the food, and reconstituted with hot water. The skin layer is recognized on the surface, and the thickness of the skin layer is in the range of 0.05 to 2.0 mm .

In the method for producing a freeze-dried food according to the present invention, the food that has been pretreated by cutting the food into a predetermined size and seasoning the seasoning is heated and cooked with superheated steam that exceeds 100 ° C., and then vacuumed. more freeze dried and rehydration, the skin layer was observed on the surface, the thickness of the skin layer and wherein the obtaining a freeze-dried food in the range of 0.05 to 2.0 mm.

The freeze-dried food of the present invention is a freeze-dried food obtained by the above-described method for producing a freeze-dried food, the surface of the food is heated at a high temperature, the taste of the food remains in the food, and reconstituted with hot water. , the skin layer was observed on the surface, the thickness of the skin layer is characterized by a range of 0.05 to 2.0 mm.

Claims (9)

Cooking by heating the pre-treated food with superheated steam exceeding 100 ° C,
A method for producing a freeze-dried food, characterized by subsequent vacuum freeze-drying.   The method for producing a freeze-dried food according to claim 1, wherein the temperature of the superheated steam is in the range of 120C to 400C.   The method for producing a freeze-dried food according to claim 1 or 2, wherein the time for heating with the superheated steam is 1 to 10 minutes.   The manufacturing method of the freeze-dried food of any one of Claims 1-3 which heat-cook and a sterilization process simultaneously by heating with the said superheated steam.   The method for producing a freeze-dried food according to any one of claims 1 to 4, wherein the degree of vacuum during the vacuum freeze-drying is 200 Pascal or less.   The method for producing a freeze-dried food according to any one of claims 1 to 5, wherein the pretreatment is at least one selected from cutting the food into a predetermined size and seasoning. A freeze-dried food obtained by the method for producing a freeze-dried food according to any one of claims 1 to 6,
A freeze-dried food, wherein the surface of the food is heated to a high temperature, and the umami of the food remains inside the food.   The freeze-dried food according to claim 7, wherein the moisture content of the freeze-dried food is 5.0% or less.   The freeze-dried food according to claim 7 or 8, wherein a skin layer is observed on the surface of the freeze-dried food after reconstitution with hot water.

Images