JPH0457763A - Packaging of mushrooms - Google Patents

Abstract

PURPOSE:To prevent mushrooms from lowering in freshness and their ring color from changing to brown in transit and on sale by a method wherein the mushrooms are placed in a lidless container and wrapped in a specific thin transparent film and a specific surfactant is provided on at least the interface between the film and the mushrooms. CONSTITUTION:A thin transparent film 3 for use in covering the mushrooms placed in a lidless container 1 has a steam permeating rate of 20-500g/m<2>.24 hours.(38 deg.C) and an oxygen gas permeating rate of 2000-30000ml/m<2>.24 hours.atm (23 deg.C). The surfactant consisting mainly of the saturated fatty acid having 14-22 carbon atoms and polyol ester is provided on an interface between the film and the mushrooms. This packaging method permits the mushrooms to be effectively retained in freshness during transit from a mushroom-producing district to consumers and on sale and prevents the color of the ring of the mushroom 2 from changing to brown.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a packaging method for preserving the freshness of mushrooms;
In particular, the present invention relates to a packaging method for supplying fresh pine mushrooms to consumers.

[Conventional technology]

In general, the packaging for transporting and selling mushrooms such as fresh pine mushrooms from the production area to consumers is to divide them into appropriate amounts at the production area, place them in small containers such as trays, and individually wrap them with thin transparent film. Then, they are further packed in cardboard boxes and transported to the consumption area, where, for example, the individual packaging from a supermarket is taken out of the cardboard box and sold as is on store shelves. Pvc stretch film is generally used as the thin transparent film used for individual packaging.

[Problem to be solved by the invention]

One of the purposes of using thin transparent films is to suppress respiration and moisture evaporation of fresh pine mushrooms, thereby suppressing deterioration in freshness, but current packaging films are not necessarily sufficient. Yet another purpose is to prevent raw pine mushrooms from being shaken and damaged in their individual packaging during transportation and handling. For this purpose, packaging is done tightly, and the packaging film always comes into contact with a portion of the raw pine mushrooms, but this poses a major problem. The problem is that the area around the raw mushrooms that came into contact with the film turns brown in a ring shape (hereinafter referred to as ring browning), which significantly reduces the commercial value.

[Means to solve the problem]

The present inventor conducted extensive research on what kind of packaging film for mushrooms should be in order to prevent the freshness of mushrooms, especially fresh pine mushrooms, and ring browning from occurring during the transportation and sales process, and developed the present invention. It was completed.

That is, in the present invention, when mushrooms are placed in a container with an open top and packaged with a thin transparent film, the water vapor transmission rate is 20 to 500 g/m2 24 hr (38 ° C.),
Oxygen gas permeation rate is 2,000 to 30,000 d/po.

A thin transparent film of 24 hr/atm (23°C) is used, and a surfactant mainly composed of esters of saturated fatty acids and polyols having 14 to 22 carbon atoms is interposed at least at the interface where the film contacts the mushrooms. This method of packaging mushrooms is characterized by the following.

The thin transparent film used in the present invention is, for example, LDP
E film, LLDPE film, VLDPE
Film, crystalline 1.2 polybutadiene film, E
A VA film, an ethylene-acrylic acid derivative copolymer film, a PVC film, an OPS film, etc., or a laminated multilayer film of these, each of which is unstretched, uniaxially or biaxially stretched. It is important to select the thickness of the film so that the water vapor permeation rate and oxygen gas permeation rate are appropriate values, and it is also necessary to have a certain mechanical strength.
30μ is appropriate.

The water vapor transmission rate of the film used in the present invention is 20 to 5
00g/rrr + 24hr (38°C). Preferably 20-150g/rrr・
24 hours (38°C). Water vapor transmission rate 20g
/ rrf ・If it is less than 24 hr (38° C.), evaporated water will condense and accumulate inside the package, which will easily cause rot and ring browning. Water vapor transmission rate is 50
If the temperature exceeds 0g/rd・24hr (38°C), the contents will dry out and the freshness will decrease. In addition, the oxygen gas permeation rate of the film is 2.000 to 30.0
00m/nf ・24hr-atm (23°C) is required. Preferably 8,000-30.0
00-/rrf・24hr・ate(23°C). Oxygen gas permeation rate is 2,000 d/rrr
・If it is lower than 24hr-ate (23°C), stuffiness will occur. Oxygen gas permeation rate is 30,000d/%
- If the temperature is higher than 24 hr-ate (23°C), ring browning and loss of freshness will occur. The surfactant used in the present invention is a surfactant mainly composed of an ester of a saturated fatty acid having 14 to 22 carbon atoms and a polyol. Examples of the polyols used include glycerin, diglycerin, polyglycerols higher than triglycerin, sorbitan, sorbitol, sucrose, etc.
Examples include Group I, ethylene glycol, propylene glycol, their condensates, and Group II with ethylene oxide. *The reason for using CI4 to CZZ saturated fatty acids is to prevent ring-shaped browning and improve the durability of anti-fogging. It is. In other words, even if it is a saturated fatty acid, CI4
For example, those with less than lauric acid cause ring-shaped browning and have poor anti-fog durability. Furthermore, unsaturated fatty acids such as oleic acid and liluic acid with CI4 to C0 cause ring-shaped browning and do not have sufficient anti-fogging properties. Furthermore, fatty acids exceeding C2□ are difficult to obtain and are not practical, and surfactants made of these fatty acids are not suitable for the present invention.

Examples of fatty acids most suitable for the present invention are myristic acid, balmitic acid, stearic acid, isostearic acid, behenic acid, etc., and mixed fatty acids thereof.

Saturated fatty acids with 14 to 22 carbon atoms may contain unsaturated fatty acids with 14 to 22 carbon atoms or fatty acids with 13 or less carbon atoms within a certain range, and early development of processability, transparency, and antifogging properties. From the above points, the ratio of saturated fatty acid ester having 14 to 22 carbon atoms and at least one fatty acid ester selected from unsaturated fatty acid ester having 14 to 22 carbon atoms, fatty acid ester having 13 or less carbon atoms, etc. is 40 to 100:
60-0 is preferable, and this ratio is 50-80:50
-20 is more preferable.

Methods for interposing the surfactant at the interface where the film and the mushroom come into contact include a method in which the surfactant is kneaded into the raw material resin during film production, and the surfactant is allowed to bleed onto the film surface; A method such as applying a surfactant to the surface may be used as appropriate.

In the present invention, the appropriate amount of surfactant to be present at the contact interface is 0.01 to 0.2 g per 1M of film; less than 0.01 g will result in insufficient antifogging properties, and more than 0.2 g will result in insufficient antifogging properties. The film becomes sticky or loses transparency.

〔Example〕

EXAMPLES Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to these examples. The evaluation method and criteria for mushroom preservation tests are as follows.

(1) Ring browning 48 hours after packaging, the area around the contact area of the pine mushroom with the film was visually observed, and judgment was made based on the presence or absence of ring-shaped browning.

O No browning at all in any of the packs × Browning in even one of the pine mushrooms (2) Anti-fogging Judgment is made by observing the state of water droplets adhering to the inner side of the pack 24 hours after packaging. did.

O Items with no water droplets attached △ Items with transparent large water droplets × Items with small, white-looking water droplets attached to part or the entire surface (3) 96 hours after being packaged with persistent anti-fog properties The anti-fogging properties are the same as in (2).

(4) Based on the weight of the pine mushroom at the start of the weight loss test, 7
The weight loss rate after 2 hours was evaluated.

O weight reduction rate less than 1% 8. Weight reduction rate: 1 or more and less than 2% × Weight reduction rate 2% or more Note that if the weight reduction rate is 2% or more, the taste will be poor.

(5) Stuffy odor test The sample was opened after 72 hours and immediately smelled to determine the odor.

O: Almost no alcohol odor △ Slight alcohol odor × Strong alcohol odor (6) Judgment was made based on the number of days until yellowing or browning in spots began to appear during the rot preservation test.

0 06 days or more Δ Appeared in 4 days or more but less than 6 days × Appeared in less than 4 days Examples 1 to 5 and Comparative Examples 1 to 5 Surfactants A-1 to 10 shown in Table 1 A 0.5% ipropyl alcohol solution was coated on the surface of the film shown in B-1 in Table 2 at 9 g/rrf (wet), and then dried and subjected to a packaging test. Length 180mm,
PSP (width: 100 cm, depth: 20 m) Place fresh white pine mushrooms (with legs cut out) with a pixel diameter of 30 - 40 am on a tray with the pixel facing up.
They were lined up one by one and packaged so that the coated side of the film was in contact with the pine mushrooms. Ten packs of each film were stored in a constant temperature and humidity chamber at 20° C. and 50% humidity. The evaluation results are shown in Table 3. Ring browning did not occur in the packages packaged with the film coated with the surfactant of the present invention, but browning occurred in all the films coated with other surfactants. In addition, those using A-6 and A-7 as surfactants had slightly poor sustained antifogging properties. All samples had no problems with loss of weight, stuffy odor, and rot.

Examples 6 to 10 and Comparative Examples 6 to 9 A 0.5% isopropyl alcohol solution of surfactant A-1 shown in Table 1 was applied to the surface of the films shown in B-2 to B-10 of Table 2 in Example 1. It was coated in the same manner as above, and a packaging storage test was conducted on pine mushrooms. The evaluation results are shown in the fourth
Shown in the table. Examples 6 to 10, in which the water vapor permeation rate and the oxygen gas permeation rate are within the range of the present invention, showed good results with no problems with ring browning, anti-fogging properties, sustained anti-fogging properties, thinning, stuffy odor, and rot. Ta. In Comparative Example 6, which had a low water vapor transmission rate, ring browning and rot occurred. In Comparative Example 7, which had a high oxygen gas permeation rate, ring browning occurred. Comparative Example 8, which had a high water vapor transmission rate, had a large loss of weight. In Comparative Example 9, which had a low oxygen gas permeation rate, stuffy odor and putrefaction occurred.

Examples 11 to 17 and Comparative Example 10.11 Table 2 B-2
A-2 in Table 1 was used as the surfactant.
A mixture of A-6 and A-6, or a mixture of A-3 and A-8 was dissolved in isopropyl alcohol and coated in the same manner as in Example 1, and the film was used to conduct a preservation test on pine mushrooms. The results are shown in Table 5. Carbon number 14~
The ratio of 22 saturated fatty acid esters to at least one fatty acid ester selected from unsaturated fatty acid esters having 14 to 22 carbon atoms and fatty acid esters having 13 or less carbon atoms is 4.
0 to 100: Ring browning did not occur in the case of 60 to O, but the above ratio with at least one fatty acid ester selected from unsaturated fatty acid esters having 14 to 22 carbon atoms and fatty acid esters having 13 or less carbon atoms When the amount exceeded 60-t%, ring browning occurred. Also, the above ratio is 50~
80. : When the rating was 50 to 20, Harannu's anti-fog and long-lasting anti-fog properties were particularly good.

Examples 18-21. and Comparative Example 12.13 B- in Table 2
Using the film shown in 2, coating it with isopropyl alcohol solutions of various concentrations of a 50:50 mixture of A-1 and A-5 in Table 1 as a surfactant, and measuring the amount of surfactant present on the film surface. Using samples with different values, the same procedure as in Example 1 was carried out. The mushrooms were packaged and subjected to a storage test to examine their antifogging properties and sustained antifogging properties. The results are shown in Table 6. In addition, the surface stickiness and transparency are as follows:
Judgment was made by touch and visual observation.

Examples 22 to 24 Consisting of surface layer/intermediate layer/core layer/intermediate layer/surface layer, thickness 10 with layer composition ratio of 10/35/10/35/10
A 5-layer μ film was prepared using the following recipe. The surface layer is VAc: 15% by weight of EVA with 0.2% by weight of surfactant added based on the entire layer and extruded using a 40mmφ extruder, and the intermediate layer is made of 70% of the above EVA and 15% of PP with MFR=3. , 15% polyolefin elastomer (Tafmer P) mixed resin with 0.0% surfactant on the whole layer basis.
6% by weight was added and extruded using a 50+m++φ extruder.For the core layer, a mixed resin of 70% PP and 30% polybutene was extruded using a 40sφ extruder, and a 50μ parison was produced using a 5-layer circular die. was heated to 45° C. and stretched 2 times in length and 2.5 times in width to obtain a 10 μm film. After aging this at 25"C for 2 days, a packaging preservation test of pine mushrooms was carried out in the same manner as in Example 1. Table 7 shows the surfactant formulation and test results. In all cases, ring browning occurred. There was no occurrence, and both the anti-fogging property and the sustained anti-fogging property were good, and there was no loss of weight, stuffy odor, or rotting.By cross-extruding the surfactant into the raw resin in this way, it was not possible to coat the resin. No separate process is required, and there is no need to use a solvent.Also, by mixing a surfactant, the melting point is lower than when using a saturated fatty acid ester having 14 to 22 carbon atoms alone, simplifying the manufacturing process. In addition to improving the transparency and slipperiness of the film, it is extremely convenient.

Table 1 [Effects of the Invention] The method of the present invention makes it possible to control the respiration and water vapor of mushrooms, effectively preserving the freshness of mushrooms. Browning can be prevented. Furthermore, the thin transparent film used in the present invention is
It also has excellent anti-fogging properties, and is the most suitable packaging method for transporting and selling mushrooms other than pine mushrooms, such as fresh shiitake mushrooms, shimeji mushrooms, and maitake mushrooms from their production areas to consumers.

Further, the present invention may be used for packaging other than mushrooms, such as fresh vegetables, fruits, pickles, and other uses, and is not limited to such packaging.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing ring browning that occurs in fresh pine mushrooms packaged with a conventional film. 1 is a tray, 2 is a raw pine mushroom, 3 is a film, 4
indicates a ring browning area.

Claims (1)

[Claims] When mushrooms are placed in a container with an open top and wrapped in thin transparent film, the water vapor transmission rate is 20 to 500 g.
/m^2・24hr (38℃), and the oxygen gas permeation rate is 2,000 to 30,000ml/m^2・24hr.
・A thin transparent film of ATM (23°C) is used, and a surfactant mainly composed of esters of saturated fatty acids and polyols having 14 to 22 carbon atoms is interposed at least at the interface where the film contacts the mushrooms. A packaging method characterized by: