JPH11231074A - Food material after-maturing degree evaluating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evaluate the after-maturing degree of a food material by measuring a hue shown when dye in a dye containing layer is diffused in a dye penetrated layer under accumulated temperature with the lapse of time. SOLUTION: A temperature history indicator has a dye penetrated sheet 1 comprising a dye penetrated layer of an opaque low-density polyethylene film, and a dye support sheet 3 on which a dye containing layer 2 comprising printing ink containing dye is printed. Food material is stored in a separated state of the dye penetrated sheet 1 and the dye support sheet 3 with the dye containing layer on the surface. Since the dye penetrated sheet 1 is opaque, the hue of dye is invisible before the penetration and diffusion of the dye. With the lapse of time, the dye penetrates into the dye penetrated sheet 1 and is diffused therein, and the penetration and diffusion of the dye make progress depending on accumulated temperature, so that dye concentration in the dye penetrated sheet 1 becomes high. The progress of specified accumulated temperature is thus indicated by the temperature history indicator to evaluate the after- maturing degree of the food material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for evaluating the degree of ripening of a food material which is ripened in a distribution process or storage and then eaten.

[0002]

2. Description of the Related Art Banana, kiwifruit, pear, muskmelon and the like are fruits that are harvested, ripened, and then eaten. Since the skin color of a banana changes, it is easy to determine the degree of ripening. However, kiwifruit, pear,
Even if ripening progresses, the appearance of the skin and the like of the musk melon is small, and it is difficult to determine the degree of ripening. For this reason, conventionally, the degree of ripening has been determined based on the tactile sensation. However, since accurate determination requires skill, consumers have erroneously determined the best-before date. If it is earlier than the expiration date, there will be no sweetness, and if it is later, it will rot.

[0003] In addition to fruits, some meats and seafoods may be ripened to improve the taste, but have the same problem.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a method for evaluating the degree of ripening of a food material, which can easily and accurately determine the best-tasting time of a ripened food material. The purpose is to provide.

[0005]

The method for evaluating the degree of ripening of a food material of the present invention, which has been made to achieve the above object, is as follows.

As shown in FIG. 1, the method of evaluating the degree of ripening of a food material to which the present invention is applied is such that the dye in the dye-containing layer 2 penetrates and diffuses into the dye-penetrating layer 1 at an integrated temperature over time. Is a method for evaluating the ripening degree of a food material.

The accumulated temperature over time is the product of temperature and time. There is a correlation between the integrated temperature and the degree of ripening of the ripened food material. On the other hand, the concentration of the dye that has permeated and diffused into the dye permeation layer 1 increases depending on the integrated temperature, and a different hue appears according to the integrated temperature. The degree of ripening of the food material can be evaluated based on the hue. Therefore, the taste time of the food material can be easily determined.

In this method of evaluating the degree of ripening of a food material, it is preferable that the dye-containing layer 2 is brought into contact with the dye-penetrating layer 1 and immediately stored with the food material.

[0009] The degree of ripening of the food material can be evaluated by the color difference in hue before and after the passage of time.

The food material is, for example, a collected fruit.
The present invention can also be applied to vegetables that require ripening after collection. Depending on the type of meat, shellfish and the like, the degree of ripening can be evaluated by the method of the present invention after slaughter or after catch.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for evaluating the degree of ripening of the present invention will be described in detail with reference to the drawings corresponding to the embodiments.

The method for evaluating the degree of ripening of a food material is evaluated by using a temperature history indicator having a dye-containing layer and a dye-penetrating layer. As shown in FIG. 1, the temperature history indicator has a sheet 1 composed of a dye-permeable layer of an opaque low-density polyethylene film and a dye support sheet 3 on which a dye-containing layer 2 composed of a printing ink containing a dye is printed. ing. The surface of the dye-penetrating sheet 1 in contact with the dye-containing layer 2 has an adhesive layer (not shown).

Before storing the food material, as shown in FIG. 1A, the dye-permeable sheet 1 and the dye-supporting sheet 3 having the dye-containing layer 2 on the surface are stored separately. At the start of the ripening of the food material, they are pasted together as shown in (b) and stored together with the food material. Since the dye-penetrated sheet 1 is opaque, the hue of the dye cannot be seen in a state where the dye has not penetrated and diffused. As time elapses, the dye penetrates and diffuses into the dye permeation sheet 1 as shown in FIG. Depending on the accumulated temperature, the permeation and diffusion of the dye proceed in a wide range, and the dye concentration in the dye permeation sheet increases. Since the temperature history indicator showing the hue in this way indicates that the predetermined integrated temperature has elapsed, the ripening degree of the food material can be evaluated.

The degree of ripening can also be evaluated by measuring the color difference of the hue before and after the passage of time with a colorimeter.

The kind and content of the dye and the material and thickness of the dye-penetrated sheet are adjusted according to the integrated temperature to be controlled.
A predetermined hue can be displayed when the optimum integrated temperature is reached. At this time, it is preferable to attach a standard color indicating the degree of ripening to each food material.

The following is an example in which La France, a kind of pear, is adopted, and the method for evaluating the degree of ripening of the present invention is experimented.

The pears harvested in October 1997 are subjected to a pre-cooling treatment at 5 ° C. for 10 days prior to ripening,
Initial conditions have been prepared. On the other hand, the degree history indicator was prototyped as follows.

900 parts by weight of an ink vehicle (NSP Medium, manufactured by Jujo Kako Co., Ltd.) and a dye (CI. 2612)
5) A composition of 10 parts by weight, a solvent (cyclohexanone) 80 parts by weight, and an additive (talc) 10 parts by weight was kneaded to produce a permeable printing ink. 150 printing inks
The polyester film was screen-printed by a mesh silk screen to form a dye-containing layer on the dye support sheet. On the other hand, an adhesive (Y-9460) is applied to a low-density polyethylene film (white: film thickness: 20 μm) having a three-layer structure.
(Manufactured by PC, 3M) and applied on a dye-permeable sheet to obtain a temperature history indicator.

After the pre-cooling treatment, the pear is at room temperature, 15 ° C.
Ripening was carried out under three conditions of 10 ° C. During the ripening period, it was stored with the prototype temperature history indicator. The following measurement was performed for the hue indicated by the temperature history indicator and the degree of ripening.

The hue change (color difference ΔE) of the temperature history indicator at the start of ripening and after the ripening is measured by a colorimeter CR-100.
(Minolta Camera Co., Ltd.). As an evaluation index of the degree of ripening, the penetration hardness was measured by a fruit hardness meter FT011 (Fujidaira Industry Co., Ltd., plunger diameter 8 mm).

FIG. 2 is a diagram in which the ripening condition is room temperature, and the horizontal axis indicates the integrated temperature, and the vertical axis indicates the color difference ΔE and the penetration hardness. This indicates that the color difference ΔE increases and the penetration hardness decreases depending on the integration time.

At the start of ripening at room temperature, the temperature history indicator was white. When the color difference (ΔE) was 10 in the middle period, the temperature history indicator showed pink, and the ripening was not completed even by the taste. At an integrated temperature of about 4000 (° C. · hour), the penetration hardness was about 10 (N), which is the best season, and the ripening was completed depending on the taste. At the completion of ripening, the temperature history indicator showed red, and the color difference (ΔE) was 25.

As described above, the degree of ripening could be evaluated based on the hue and color difference indicated by the temperature history indicator.

Under ripening conditions at 10 ° C. and 15 ° C., at an integrated temperature of about 6000 (° C./hour), a penetration hardness of about 10 (N)
At this time, the temperature history indicator was red, and the color difference (ΔE) was 25. As in the case of the room temperature, when the color difference becomes 25, it can be determined that it is the best season.

For fruits other than pears, it is possible to evaluate the degree of ripening of net melon, kiwifruit and the like.

[0026]

As described above in detail, the method for evaluating the degree of ripening of a food material according to the present invention makes it possible to easily and accurately determine the best season of a ripened food material. Consumers can determine the degree of ripening without cutting through the food material.
There is no need for destructive inspection using equipment. Consumers can eat food ingredients at the best time to eat.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a temperature history indicator used in a method for evaluating a ripening degree of a food material to which the present invention is applied.

FIG. 2 is a graph showing changes in integrated temperature, color difference, and penetration hardness of a pear.

[Explanation of symbols]

1 is a dye penetration layer, 2 is a dye containing layer, and 3 is a dye support sheet.

Continuation of the front page (72) Inventor Shigemi Kajiwara W-11, TS-11 Kawagoe 1-11-17 Sunashida, Kawagoe-shi, Saitama

Claims (4)

[Claims] 1. The color in which the dye in the dye-containing layer penetrates and diffuses into the dye-permeating layer at an integrated temperature over time,
A method to evaluate the degree of ripening of food materials. 2. The method for evaluating the degree of ripening of a food material according to claim 1, wherein the dye-containing layer and the dye-permeable layer are brought into contact with each other and immediately stored together with the food material. 3. The method according to claim 1, wherein the evaluation is performed based on a color difference of the hue before and after the elapse of the time.
The method for evaluating the degree of ripening of food materials described in 1. 4. The method for evaluating the ripening degree of a food material according to claim 1, wherein the food material is a collected fruit.