JPH10327749A - Cut lettuce packed in container and prevention of browning of lettuce - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject cut lettuce resistant to browning and withering to soft state even by holding in a container by including an alcohol in the gaseous phase in the vessel at a specific concentration. SOLUTION: The objective cut lettuce is produced by including alcohol in the gaseous phase of the vessel holding the cut lettuce at a concentration of 2.4-6.7 mg/L. The 'cut lettuce held in a container' means a cut lettuce held (filled or sealed) in a plastic container having a lid, a bag made of a plastic film, etc., and the 'container' is e.g. a lidded tray made of a rigid plastic or foamed polystyrene or a bag made of polyethylene or nylon film. The 'lettuce' is e.g. sunny lettuce and salad lettuce and the term 'containing alcohol' means the state of alcohol (ethanol) existing in the gaseous phase in the form of gas (vapor).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to cut lettuce packed in containers and a method for preventing browning thereof.

[0002]

2. Description of the Related Art Conventionally, when vegetables are cut, enzymes responsible for discoloration in the vegetables are activated by enzymes or the like on the cut surface, and discoloration usually occurs in cut vegetables one to two days after cutting. There is a problem that the commercial value is easily lost because the brown color is conspicuous. Therefore, to prevent browning of cut lettuce,
A method has been proposed in which an alcohol solution is brought into contact with a cut lettuce and then packed into a bag (Japanese Patent Laid-Open No. 2-227027).

[0003] However, the cut lettuce obtained by the above method has a problem in that the surface of the cut lettuce shrinks to a pimpled state because the surface of the cut lettuce is in contact with the alcohol solution in a spray or liquid state. .

[0004]

SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides a packaged cut lettuce which hardly causes browning even when the cut lettuce is stored in a container, and which does not easily wilted to a pearless state, and a method for preventing browning thereof. The purpose is to provide.

[0005]

Means for Solving the Problems In view of such circumstances, the present inventors have made various studies, and as a result, obtained a finding that the above object can be achieved by aeration with alcohol. As a result of further research based on the above, the present invention was completed.

That is, the constitution of the present invention is as follows. The invention according to claim 1 is that "a gaseous phase part in a container containing cut lettuce contains 2.4 mg / l to 6.7 mg / l alcohol. The invention according to claim 2 is characterized in that alcohol is contained in the gaseous phase portion of the container containing the cut lettuce. Method for Preventing Lettuce Browning ".

Next, the present invention will be described in detail. In the present invention, "%" means "% by weight". In the present invention, the “cut lettuce packed in a container” means a cut lettuce that is contained (filled and sealed) in a synthetic resin container with a lid, a synthetic resin film bag, or the like. Examples of the "container" include a tray with a lid made of hard plastic or styrofoam, and a bag of polyethylene or nylon film. Examples of "lettuce" include sunny lettuce and salad vegetables. In the present invention, “containing alcohol” refers to a state in which alcohol (ethanol) exists as a gas (vapor) in a gas phase.

[0008] The present invention is characterized in that the container in which the cut lettuce is housed contains an alcohol having a concentration of 2.4 mg / l to 6.7 mg / l in the gas phase portion. Lettuce and its browning prevention method. Here, "contains an alcohol having a concentration of 2.4 mg / l to 6.7 mg / l" means that alcohol corresponding to 2.4 mg to 6.7 mg in 1 L of the gas phase contains gas (vapor). Say. If the concentration is lower than 2.4 mg / l, the cut lettuce does not wither, but browning occurs on the third day of storage. If the concentration is higher than 6.7 mg / l, browning can be prevented but the cut lettuce is withered. Since the cut lettuce is accommodated in a container having a gaseous phase portion containing an alcohol having such a concentration, the alcohol liquid does not directly come into contact with the cut lettuce, and thus the surface of the cut lettuce is not withered. It becomes stuffed cut lettuce. In addition, with this configuration, the cut lettuce comes into contact with the gas phase containing alcohol, so that browning of the cut lettuce in the container can be prevented.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to produce a cut lettuce packed in a container according to the present invention, first, a plastic tray with a lid is prepared as an example of a container. After the alcohol solution is dropped on the bottom of the tray, the tray is closed. Here, the concentration of the alcohol solution is preferably as high as 90 to 100%.
The higher the concentration, the smaller the amount of alcohol used, the better
This is because the alcohol is less likely to come into contact with the cut lettuce, and at the same time, the evaporation speed is increased, so that the alcohol can be rapidly aerated in the gas phase.

Next, lettuce leaves prepared separately were cut from the root of the strain, and sodium hypochlorite was added at 50 ppm to 3 ppm.
Immerse in a 00 ppm aqueous solution. Then wash with water. Except for the petiole (core) of this sterilized lettuce, one side is about 3cm
And cut into cut lettuce. The cut lettuce is stored in a tray on which the alcohol liquid has been dropped. At this time, the alcohol liquid is dropped on the bottom of the tray, so even if cut lettuce is stored from above, most of the cut lettuce does not come into contact with the alcohol liquid, but the cut lettuce and the alcohol liquid come in contact In order to completely prevent this, for example, a groove or the like may be formed at the bottom of the container so that the alcohol solution stays in the groove. The cut lettuce packed in a container of the present invention thus obtained does not wilt even after storage at 15 ° C. for 7 days, and has no commercial browning and is of commercial value.

[0011]

Test Examples Hereinafter, the present invention will be described in more detail based on test examples. After washing one sunny lettuce (approximately 300 g) with water, lettuce 200 g cut into a size of about 4 cm 2
Is immersed in a 200 ppm sodium hypochlorite solution for 10 minutes and then washed with water. Separately, 0.27 ml, 0.5 ml, and 1 ml of 100% alcohol solution were dropped on the bottom of a plastic container with a lid having a base of 8.4 cm and a height of 4 cm, respectively. Cover the lid. Alcohol concentration in the container is 2.4 each
mg / l, 4.6 mg / l, and 6.7 mg / l cut-packed lettuce were designated as invention, invention, and invention, respectively. Similarly, 100% alcohol was placed on the bottom of the container at 0 ml, 0.14 ml, 0.25 ml, and 1.04 m, respectively.
1, 3 ml are dropped, and the alcohol concentration in the container is 0 m each.
g / l, 1.2 mg / l, 2.2 mg / l, 6.9 mg
/ L, and 11.0 mg / l, respectively, as a comparative product, a comparative product, a comparative product, a comparative product, and a comparative product. Furthermore, 20 g of the sterilized cut lettuce was immersed in an aqueous solution having an alcohol concentration of 30% for 10 minutes, and after draining, the plastic container with the lid was used as a comparative product.

The cut lettuce packed in a container thus obtained was stored at 15 ° C. for 1 day, 3 days, and 7 days after trial production, and changes in browning and wilting were observed. The appearance test of browning of the cut lettuce packed in a container was performed by the method shown in Note 1), and the appearance test of the withering of the cut lettuce packed in a container was performed by the method shown in Note 2).

The symbols in the table are shown below. Note 1) Evaluation criteria for browning of cut lettuce The browning state of cut lettuce was evaluated in five steps as follows. Evaluation criteria for browning ◎ No browning is observed ○ There is a slight tendency to browning △ Slight browning is observed × Clear browning is observed ×× Extremely browning is observed Note 2) Evaluation criteria for wilting cut lettuce ◎ Wilting No ○ There is a tendency to wither slightly △ Somewhat withering is observed × Clear withering is observed ×× Extremely withering is observed

[0014]

[Table 1]

From the results shown in the above table, it can be understood that the cut lettuce packed in the container of the present invention does not wither and the browning of the cut lettuce leaves does not occur even after storage for 7 days.

[0016]

EXAMPLE The root of one salad vegetable (about 250 g) was cut with a kitchen knife, the leaves were peeled off one by one, washed with water, immersed in a 200 ppm aqueous solution of sodium hypochlorite for 10 minutes, washed with water and drained. From each of the salad vegetables, a leaf petiole (core) was cut out one by one, and one side was cut into a size of about 4 cm to obtain 180 g of carletta. Then put 99 pcs on the bottom of the plastic tray with lid (10 cm bottom, 4 cm height).
0.8 ml of 1% ethanol first grade (manufactured by Nippon Alcohol Sales Co., Ltd.) was dropped, and then 30 g of the sterilized cut lettuce described above
Was placed in a container and capped immediately. When the cut lettuce packed in a container was stored at 15 ° C., browning did not occur even after 7 days had passed, and the leaves were not wilted. The alcohol concentration in the gas phase immediately after the evaporation of the alcohol solution after the production was measured and found to be 5.1 mg / l.

[0017]

As described above, according to the present invention, it is possible to provide a container-packed cut lettuce which hardly causes browning and which does not wither. Further, according to the method of the present invention, the cut lettuce can be withered. And browning can be prevented.

Claims (2)

[Claims] 1. A cut lettuce packed in a container, characterized in that a gas phase in a container containing the cut lettuce contains 2.4 mg / l to 6.7 mg / l alcohol. 2. A method for preventing browning of cut lettuce, characterized in that an alcohol is contained in a gas phase in a container containing cut lettuce.