JPH03180143A - Production of cut fruit - Google Patents

Abstract

PURPOSE:To obtain cut fruit preservable for a long period by cold storage and capable of maintaining fresh texture by packing cut fruit with a packaging material having oxygen barrier properties in vacuum and then keeping the fruit in liquid under high pressure to sterilize the fruit and to inactivate enzymes in the fruit. CONSTITUTION:Washed fruits are optionally peeled, cut and packed in vacuum with a packaging material having oxygen barrier properties. A pouch comprising a thermoplastic resin having 0-20cc/m<2>hr.atm calculated as 30mu oxygen permeability is used as the packaging material. In this case, preferably the fruits are immersed in an aqueous solution of organic acid (salt), salt, etc., and packed in vacuum. Then, the fruits packed in vacuum are maintained under >=1,000kg/cm<2> for >=3 minutes so that the surface of the fruits is sterilized and enzymes in the fruits are effectively inactivated. In the cut fruit products obtained by the above-mentioned method, microorganisms are hardly found and the cut fruits have excellent shelf stability and even after long-time preservation by cold storage, the cut fruit products have characteristic texture of fruit and high commercial value.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing cut fruit,
More specifically, the present invention relates to a method for producing cut fruit that retains a "raw" texture and can be stored for a long period of time without boiling or sterilizing or sugaring.

[Conventional technology]

Conventionally, cut fruits were packaged with lamp film and then sold. It is also known to produce cut fruit products by boiling or sterilizing the fruit after cutting it or by sterilizing it in sugar.

[Problem to be solved by the invention]

Conventional fruit that is simply wrapped in lamp film after cutting suffers from a significant drop in freshness after cutting, and even when stored in a refrigerator, the edible period is very short, 1 to 2 days. In addition, browning occurs in fruits due to enzymes in cells and oxygen in the air at a relatively early stage after processing when they can be consumed from a food hygiene perspective, which significantly reduces commercial value and is a major problem. Met. Furthermore, methods of sterilizing fruit after cutting by boiling or pickling in sugar extend the shelf life, but there is a problem in that the original freshness and texture of the fruit is lost.

Therefore, in order to improve the image of cut fruit products and increase consumption, the inventors of the present invention have developed cut fruits that have a good shelf life and have the freshness and texture inherent to the fruit. As a result of deepening our recognition that this is an important issue in the industry and conducting extensive research, we have completed the present invention.

[Means to solve the problem]

The present invention is intended to solve the above-mentioned problems, and is capable of producing cut fruit that can be stored for a long period of time under refrigeration and has the original "raw" texture of the fruit, especially freshness and texture. Regarding the method.

Specifically, the present invention cleans the fruit, peels the skin if necessary, and then cuts the fruit, vacuum-packages the fruit using a packaging material having oxygen barrier properties, and places the packaged fruit in a liquid. The present invention relates to a method for producing cut fruit, characterized in that the fruit is sterilized and enzymes in the fruit are deactivated by holding the fruit under a pressure of 1000 kg/co1 or more for 3 minutes or more.

Hereinafter, the present invention will be explained in detail for each step.

Since there are many bacteria attached to the outer skin surface of the fruit,
Wash thoroughly, peel if necessary, and cut into shapes that are easy to eat.

Vacuum packaging using packaging materials with oxygen barrier properties prevents quality deterioration due to oxidation caused by oxygen remaining in the packaging system and oxygen passing through the packaging material, and prevents quality deterioration caused by air remaining in the packaging system. This is to prevent pressure loss.

As a packaging material, a pouch made of a thermoplastic resin film can be used.

As the thermoplastic resin film, those having the following specifications can be used, but are not limited to the following.

KON/CPP, KEPT/CPP, KOP/CPP,
PET/AI/CPP, PET/AI/EVA, PET
/AI/PS (Of the abbreviations, K is polyvinylidene chloride coat, ON is oriented nylon, C is unstretched, PET is polyethylene terephthalate, OP is stretched polypropylene, P
E is polyethylene, AI is aluminum foil, EVA is ethylene vinyl acetate copolymer, PP is polypropylene, and PS is polystyrene. ) The oxygen permeability of the packaging material is 0 to 20cc/ when converted to 30μ.
rrT ・24 hrs -atm Preferably 0 to 10
CC/BO・24hrs-ATM.

Further, it is preferable that the fruit be vacuum-packed after being immersed in an aqueous solution of one or more selected from organic acids, organic acid salts, and salt.

That is, since organic acids, organic acid salts, and common salts have antibacterial effects, they have the advantage of shortening the treatment time due to the synergistic effect with high-pressure treatment.

In addition, among fruit deterioration, browning due to oxidation of phenolic compounds to 0-quinone by polyphenol oxidase in fruit is a problem as well as microbial deterioration, but polyphenol oxidase activity is
It reaches a maximum around ~7, and when the pH is lowered to 3 or less, the residual activity becomes almost O. That is, by immersing the fruit to be subjected to high-pressure treatment in an organic acid in advance, it becomes possible to effectively deactivate the enzymes in the fruit.

As the organic acid, one or more types of ascorbic acid, citric acid, malic acid, oxalic acid, tartaric acid, benzoic acid, etc. can be used. The above is preferable.

Although the reason is not clear, it is conventionally known that various salts have the ability to suppress browning of fruits. That is,
By immersing fruits to be subjected to high-pressure treatment in an organic acid salt aqueous solution or saline, browning of the fruit can be suppressed even if polyphenol oxidase activity remains after high-pressure treatment.

As the organic acid salt, one or more of the above-mentioned sodium salts, potassium salts, magnesium salts, calcium salts, etc. of the organic acids can be used; Sodium ascorbate or a mixture of sodium ascorbate and sodium citrate and/or sodium malate as a substrate is preferred.

The concentrations of organic acids, organic acid salts, and salts are not particularly limited as long as they do not lose the "raw" taste of the fruit and a sufficient effect can be obtained, but concentrations of 0.01% to 5% by weight each may be used. Aqueous solutions can be used.

■100 Q afl with the upper 2'
By holding the fruit after vacuum packaging in a liquid under a pressure of 1000 kg/era or more for 3 minutes or more, the surface of the fruit can be sterilized and the enzymes in the fruit can be effectively deactivated. can be done.

Since it is sterilized in the packaged state, there is no need to worry about contamination during packaging, and it is also excellent in terms of food hygiene.

As the high-pressure treatment is performed under the above conditions, hydrophobic bonds and salt bonds within the object to be subjected to high-pressure treatment are severed, and hydrogen bonds tend to be generated. In other words, three types of non-covalent bonds in the high-pressure treated body are formed or destroyed by interaction with water, and proteins denature and lose their functions, deactivating enzymes in the fruit and further damaging the fruit. It is also possible to sterilize any remaining germs.

When treating at high pressure, if the pressure is less than 1000 kg/cffl or the holding time is less than 3 minutes, it is not possible to effectively sterilize the surface of the fruit and deactivate the enzymes in the fruit.

On the other hand, in high-pressure treatment, vitamins and aroma components made up of covalent bonds are not destroyed, so unlike sterilization by heating, heating odor does not occur and vitamins are not destroyed.

The liquid used when treating the package under high pressure is not particularly limited as long as it is liquid, but potable tap water is preferable in terms of hygiene and cost.

Furthermore, it is naturally possible to efficiently sterilize and destroy enzymes by heating the treatment liquid during high-pressure treatment.

[Effects of the Invention] The present invention effectively sterilizes fruits and deactivates enzymes in fruits by high-pressure treatment without heating, particularly by using high pressure in combination with organic acids, organic acid salts, salt, etc. , and the processing time can be shortened.

Almost no microorganisms are found in the cut fruit products produced by the method of the present invention, and they have excellent storage stability.

Moreover, even after long-term storage in refrigeration, the fruit retains its original "raw" texture, i.e., freshness, texture, color, etc., and its commercial value is extremely high. Also,
The method for producing cut fruit of the present invention is a safe method from a food hygiene standpoint, and has high industrial utility value.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Note that the concentrations of aqueous solutions of organic acids, organic acid salts, common salts, etc. are expressed in weight %.

[Examples] Example 1 After washing an apple, it was divided into two lengthwise, the core was removed, and the apples were immersed in a 2% ascorbic acid aqueous solution for 5 minutes. Then the apple 1
KON/CPP pouch (width 210mm, length 210mm)
Vacuum packaging was performed using

The apples after the packaging described above were filled into a high-pressure device for food as shown in FIG. 1, and subjected to high-pressure treatment for 4000 atm x 10 minutes.

Comparative Example 1 After washing an apple, it was divided into two lengthwise, the core was removed, and the apple was immersed in a 2% ascorbic acid aqueous solution for 5 minutes. Then the apple 1
KON/CPP pouch (width 21On+m, length 21
0mm).

Twenty packs each produced in Example 1 and Comparative Example 1 were stored at 100C for 10 days and 20 days, and tests were conducted on swelling of the packaging material, generation of off-odor, and sensory evaluation.

The results are shown in Table 1.

(Evaluation method) - Expansion of packaging material: Out of 20 sample packs, evaluation was made based on the number of packs that expanded due to generation of carbon dioxide gas inside the packaging.

Example: Number of packs/200 Off-odor occurrence: Out of 20 sample packs, the evaluation was based on the number of packs in which an off-odor occurred.

Example, number of pieces/200 Sensory evaluation: Freshness (freshness), texture, color, etc. when eaten were comprehensively evaluated from a taste and visual perspective.

(Margins below this page) As is clear from Table 1, the cut fruit products produced by the method of the present invention do not cause swelling of the packaging material even after long-term storage, and do not generate off-flavors caused by microorganisms. It maintained its original color and had an excellent texture.

[Brief explanation of drawings]

FIG. 1 shows the overall structure of a high-pressure device for food used in the implementation of the present invention. l...Processing chamber, 2...High pressure container, 3...Low pressure piston, 4...Top lid, 5...High pressure piston, 6...
Hydrostatic cylinder, 7...pressure generator.

Claims (1)

[Claims] 1. The fruit is washed, peeled if necessary, and then cut, the fruit is vacuum packaged using a packaging material having oxygen barrier properties, and the packaged fruit is immersed in a liquid. 1000k
A method for producing cut fruit, characterized by sterilizing the fruit and deactivating enzymes in the fruit by holding the fruit under a pressure of g/cm^2 or more for 3 minutes or more. 2. Claim 1, in which the fruit is immersed in an aqueous solution consisting of one or more of organic acids, organic acid salts, and salt, and then vacuum packaged.
Method for producing cut fruit as described. 3. The method for producing cut fruit according to claim 2, wherein the organic acid aqueous solution is an aqueous solution of one or more kinds selected from ascorbic acid, citric acid, and malic acid. 4. The method for producing cut fruit according to claim 2, wherein the organic acid salt aqueous solution is an aqueous solution of one or more selected from sodium ascorbate, sodium citrate, and sodium malate. 5. Oxygen permeability of packaging material is 0 to 20cc/m^2.2
The method for producing cut fruit according to claim 1, wherein the cutting time is 4 hrs.atm.