JPH03183438A - Production of cut fruit - Google Patents

Abstract

PURPOSE:To obtain the title fruit useful for foods having excellent texture and shelf stability by sterilizing cut fruit in a liquid under a specific condition and inactivating an enzyme and then specifically packaging the fruit with a packaging material having oxygen barrier properties. CONSTITUTION:Cleaned fruit which is optionally peeled and cut is maintained in a liquid containing one or more of an organic acid (e.g. citric acid), an organic acid salt (e.g. sodium citrate) and salt (0.01-5.0wt.% concentration in each substance) under >=1,000kg/cm<2> pressure for >=3 minutes and sterilized, an enzyme is inactivated and the fruit is packed with a packaging material having oxygen barrier properties under <=0.05atm oxygen partial pressure to give the objective fruit.

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, the cut fruits were wrapped in U-nobu 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]

In the case of the conventional fruit simply wrapped in cling film after cutting, the freshness decreases significantly 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 their commercial value. It was a big problem. Furthermore, methods of boiling or sterilizing fruit after cutting to extend the edible period extend shelf life, but there is a problem in that the fruit's original freshness and texture are lost.

Therefore, in order to improve the image of cut fruit products and expand consumption, the inventors of the present invention aimed to develop 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, and then immerses the fruit in a liquid.
The fruit is sterilized and the enzymes in the fruit are deactivated by holding it under pressure of Okg/ctA or more for 3 minutes or more, and the fruit after the treatment is packed with packaging material that has oxygen barrier properties to reduce the oxygen partial pressure to 0. The present invention relates to a method for producing cut fruit, which is characterized in that it is packaged to have a pressure of .05 atm or less.

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.

1000kg/ctM of cut fruit in liquid
By holding the fruit under the above pressure for 3 minutes or more, it is possible to effectively sterilize the surface of the fruit and deactivate the enzymes in the fruit. By performing high-pressure treatment in liquid, pressure can be uniformly transmitted to the fruit.

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/d 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, the vitamins and aroma components that are bonded to the bottom of the tank due to covalent bonds are not destroyed, so unlike sterilization by heating, heating odor does not occur and vitamins are not destroyed.

The liquids used during high pressure treatment include organic acids, organic acid salts,
An aqueous solution of one or more selected from common salts can be used.

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 the oxidation of phenolic compounds to 〇-quinone by polyphenol oxidase in fruit tissue is a problem as well as microbial deterioration, but polyphenol oxidase activity is
It reaches a maximum around H5-7, and when pt+ is lowered to 3 or less, the residual activity becomes almost O. That is, by using an organic acid in the liquid during high-pressure treatment, it becomes possible to effectively deactivate 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; is preferred.

Although the reason is not clear, it is conventionally known that various salts have the ability to suppress browning of fruits. That is,
By using an organic acid salt or salt in the liquid during high-pressure treatment, it is possible to suppress browning of the fruit 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.

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

Oxygen partial pressure is 0 using packaging material with oxygen barrier properties.
．． The purpose of packaging to keep the temperature below 0.05 atm is to prevent quality deterioration due to oxidation caused by enzymes remaining in the packaging system and oxygen passing through the packaging material. Cups, trays, films, etc. can be used. As the thermoplastic resin cup/tray and film, those having the following specifications can be used, but are not limited to those below.

(a) Cup/tray: Polypropylene (PP) or polystyrene (PS)/
Saponified ethylene/acid picopolymer/PP or PS, P
P or PS/vinylidene chloride/PP or PS (b) Film = KON/CPP, KEPT/CPP, KOP/CPP,
PET/AI/CPP, PET/AI/EVA, PET
/At/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 stands for polyethylene, AI stands for aluminum foil, EVA stands for ethylene vinyl acetate copolymer, PP stands for polypropylene, and PS stands for polystyrene. ) The oxygen permeability of the packaging material is O to 20cc/ when converted to 30μ.
rrr・24 hrs -atm preferably ON10
CC/rd・24hrs-atm.

As a packaging method, conventionally known vacuum packaging, N2 gas displacement packaging, use of an oxygen absorber, etc. can be considered, but there are particular limitations if the packaging method allows the residual oxygen partial pressure in the packaging system to be 0.05 atm or less. Not done.

〔Effect of the invention〕

The present invention effectively sterilizes fruits and deactivates enzymes in fruits by high-pressure treatment without heating, particularly in combination with high-pressure treatment and treatment with an aqueous solution consisting of organic acids, organic acid salts, salt, etc. It is possible to shorten the processing time.

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 degree of drift of aqueous solutions of organic acids, organic acid salts, salts, etc. is expressed in weight %.

〔Example〕

Example 1 After washing an apple, the apple was cut into six lengthwise, the core was removed, and the cut apple was filled with a 2% ascorbic acid aqueous solution into a high-pressure device for food as shown in Figure 1, and heated to 4000 atmospheres
Processing was performed for IO minutes.

After high-pressure treatment, the apples were taken out aseptically, and the width was 105 mm.
Six trays were filled into a PP tray with a length of 180 mm and a depth of 35 mm.

The apples filled in the tray were placed in a PP/EVOH/PP deep-drawn tray, and using KON/CPP film as the lid material, N was poured so that the oxygen partial pressure was 0.05 atmlJ or less.
Packed with 2 gas displacement.

Example 2 A sweet summer mandarin orange was peeled to prepare peeled flesh. Along with 1% sodium ascorbate and 1% citric acid aqueous solution,
Fill the high pressure equipment for food as shown in Figure 1, and
Treatment was performed at atmospheric pressure for 10 minutes. After high-pressure treatment, remove the peeled meat aseptically, width 105 mm, length 1B011101,
15 pieces were filled in a PP tray with a depth of 35Il1m.

Place the peeled meat filled in the tray into a PP/EVOH/PP deep-drawn tray, use KON/CPP film as the lid material, and add an oxygen absorber (Ageless S-2 manufactured by Mitsubishi Gas Chemical Co., Ltd.) to the tray.
00) and N2 gas purging packaging.

Comparative example 1 After washing the apples, they were cut into six pieces lengthwise and the cores were removed.

The apples after cutting were immersed in a 2% ascorbic acid aqueous solution.

After the soaking process, the apples are taken out aseptically and the width is 10511I.
I11, 6 trays were filled into a PP tray with a length of 180 mm and a depth of 35 mm.

The apples filled in the tray were placed in a PP/EVOI (/PP) deep-drawn tray, and using KON/CPP film as the lid material, N was heated so that the oxygen partial pressure was 0.05 atm or less.
, gas exchange packaging.

Comparative Example 2 A sweet summer mandarin orange was peeled to prepare peeled flesh. 90° peeled meat
It was immersed in a 1% sodium ascorbate and 1% citric acid aqueous solution of C for 5 seconds.

After the soaking process, the peeled meat was taken out aseptically, and the width was 105 mm.
15 in a PP tray with a length of 180 mm and a depth of 35 mm.
I filled it up.

Place the peeled meat filled in the tray into a PP/EVOH/PP deep-drawn tray, use KON/CPP film as the lid material, and add an oxygen absorber (Ageless S-2 manufactured by Mitsubishi Gas Chemical Co., Ltd.) to the tray.
00) and N2 gas purging packaging.

20 each produced according to Example 1.2 and Comparative Example 1.2
Bags stored at 10°C for 10 and 20 days were tested for swelling of the packaging material, generation of off-odor, and sensory evaluation.

The results are shown in Table 1.

(Evaluation method) Expansion of O 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 expand the packaging material even after long-term storage, and do not generate any off-odor 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. DESCRIPTION OF SYMBOLS 1...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. After washing the fruit, peeling the skin if necessary, cutting the fruit, and holding the fruit in a liquid under a pressure of 1000 kg/cm^2 or more for 3 minutes or more to sterilize the fruit. The enzymes in the fruit are inactivated, and the treated fruit is packaged with oxygen barrier properties to reduce the oxygen partial pressure to 0.05a.
1. A method for producing cut fruit, characterized by packaging the fruit so that it is less than tm. 2. The method for producing cut fruit according to claim 1, wherein the liquid is an aqueous solution of one or more selected from organic acids, organic acid salts, and common salt. 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. The method for producing cut fruit according to claim 1, wherein the packaging is vacuum packaging or N_2 gas replacement packaging. 6. The method for producing cut fruit according to claim 1 or claim 5, wherein the packaging is performed by enclosing an oxygen absorber. 7. 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.