JPH02257858A - Production of preservative boiled egg - Google Patents

Abstract

PURPOSE:To improve preservation ability of boiled egg by subjecting the boiled egg to dipping treatment in an aqueous solution of harmless ash under reduced pressure. CONSTITUTION:Water is added to ash of grass or tree obtained by using torreya nucifera, pteridophyte, etc., as a raw material and the mixture is stirred and allowed to stand to afford a supernatant. A boiled egg is dipped into the supernatant and treated under reduced pressure of 30-300mmHg for about 1-2hr to provide the aimed boiled egg.

Description

[Detailed description of the invention] The present invention relates to a method for producing boiled eggs with good shelf life.

The purpose of this method is to immerse a boiled bird egg with its shell on in a weakly alkaline aqueous solution of plant ash containing large amounts of hydroxides such as calcium and magnesium.
By maintaining the egg on the alkaline side of 10.5, it is possible to easily produce boiled eggs with high shelf life at a high yield without damaging the outer shell.

Conventional boiled eggs are produced by heating with hot water, steam, or scorching heat, but during storage they become contaminated with harmful microorganisms such as mold and bacteria. In many cases, bacteria such as Salmonella, Micrococcus, and Streptococcus enter from outside the shell through the stomata of the outer shell. The process of putrefaction begins with tissue softening due to enzyme activity in albumen such as lysozyme, and then putrefaction occurs mainly due to the proliferation of bacteria. is reported to be preferable.

For the above reasons, it is difficult to store conventionally boiled eggs for a long period of time as it is, and at room temperature and pressure it takes 2 to 3 days in summer and 4 days in winter.
~5 days was the limit.

For this reason, conventional efforts have been made to improve the shelf life of boiled eggs in the shell, such as applying oil, water glass, or various paints to the surface of the shell, or placing the shell in a heat-resistant synthetic resin bag and covering it with heat. A method has been proposed in which eggs are normally preserved by sealing them off, but the process is complicated and time-consuming, the egg shells often break, the yield is low, and it is difficult to seal the eggs completely. There were drawbacks.

In the present invention, in order to solve the drawbacks of conventional boiled eggs that have a low shelf life, we first focused on plant ash, which is harmless to food, and immersed the boiled egg in this alkaline solution. By reducing the pressure inside the egg, we passed the eggshell into the egg. Allow the liquid to penetrate and adjust the pH inside the egg to 9.5~
It was discovered that a remarkable preservation effect can be obtained by maintaining the alkali level of 10.5, and this led to the completion of the present invention.

The present invention will be explained in detail below.

First, a solution of plant ash is prepared. The most preferable material for plant ash is that it is made from hay and ferns as it has a soft alkali. Add 98 parts of fresh water to 2 parts of the ash obtained from plants, stir thoroughly, and leave it. Use the supernatant liquid as the egg soaking liquid. The pH of this solution is in the range 10-12.

Next, the raw eggs washed with clear water are gradually heated in clear water and the boiled eggs taken out after 7 minutes at 92°C are immersed in plant ash solution and treated for 1 to 2 hours under a reduced pressure of 30 to 300 ■Hg. Then, the inside of the egg is deaerated and depressurized, and the plant ash liquid penetrates into the egg through the capillary tube through the pore tissue of the outer shell, so the original pi inside the egg is 10-12, rather than 7.0-8.0. Shift to weak alkaline side. Boiled eggs obtained in this way are slightly alkaline inside the egg, which lowers the enzyme activity in the egg white and prevents the egg white tissue from softening, and also suppresses the growth of microorganisms such as mold and bacteria, which prevents the egg from spoiling. It is effective in significantly inhibiting progression and increasing preservability.

In addition, the following test was conducted to examine this storage stability.

Test method Control group Washed raw eggs were gradually heated in clear water and treated at 90° C. for 7 minutes, then taken up and boiled, which was left to cool indoors to serve as a control group.

Test area: Mix 2% of the ash obtained by incinerating grasses such as grass in clear water and stir. Boiled eggs treated in the same way as the control area were immersed in this supernatant liquid, and the inside of the container was mixed with 150 ■Ig.
After being treated under reduced pressure for 2 hours, they were taken up and used as test plots.

The above control and test plots were stored in a thermostatic chamber at 15°C and humidity of 65±1%, and the 10 test samples were evaluated for interest, strange odor, yellow coloration on the surface of the albumen, secretion of mucus, and flesh quality. The number of eggs that were unfit for consumption was investigated by sensory tests such as softness and brittleness.

The results are as follows.

The numerator in the table is the number of inedible eggs, and the denominator is the number of eggs tested.

In this way, the boiled eggs immersed in ash liquid showed that the untreated control group had 3 to 4 eggs.
Compared to the storage period of about 7 days, it showed a preservation effect of 7 days or more.

Example 50 L-sized raw chicken eggs were washed with clear water, heated gradually in clear water, heated at 92° C. for 10 minutes, and then taken up to obtain hard-boiled eggs. Note that the pH of the albumen of this egg was 7.6.

Next, add 2% by weight of plant Kaya ash to clean water in advance, stir and mix, and leave to stand to obtain a supernatant liquid (pH 11,
5), and after depressurizing the inside of the container at 240 I (g) for 2 hours, 48 boiled eggs (yield: 90
%) was obtained. The po of the egg white of this boiled egg is 10.0. showed that.

When the eggs were left in a room at 5 to 10° C., the eggs had a good flavor and were preserved for more than 1 day.

As described above, according to the present invention, boiled eggs with high shelf life can be produced with a high yield without damaging the outer shell or flavor using a simple method.

Claims (1)

[Claims] A method for producing boiled eggs with good shelf life, which comprises immersing boiled eggs in an alkaline aqueous solution of harmless ash produced from plants under reduced pressure of 30 to 300 mmHg.