阅读说明：本技术 一种鸡蛋保鲜剂及其制备方法 (Egg preservative and preparation method thereof ) 是由 刘希军 于 2020-06-15 设计创作，主要内容包括：本发明提供一种鸡蛋保鲜剂,其特征在于：具体的由以下质量份的组分配制而成,壳聚糖20-30份,丁香水提物20-30份,NaCl 5-10份,海藻酸钠20-30份,乳酸5-10份,连翘精油10-20份,抑菌肽1-5份。本发明还提供一种鸡蛋保鲜剂的制备方法,本发明原材料来源广泛,操作简单,抑菌以及保鲜效果较好。原材料都是天然成分,不含有毒副作用的化学物质,使用安全。本涂膜成分简单,易于分解,对环境无毒害作用。(The invention provides an egg preservative which is characterized in that: the antibacterial peptide is prepared from the following components, by mass, 20-30 parts of chitosan, 20-30 parts of clove water extract, 5-10 parts of NaCl, 20-30 parts of sodium alginate, 5-10 parts of lactic acid, 10-20 parts of fructus forsythiae essential oil and 1-5 parts of antibacterial peptide. The invention also provides a preparation method of the egg preservative, and the egg preservative has the advantages of wide raw material source, simple operation and good bacteriostatic and preservative effects. The raw materials are all natural components, do not contain toxic or side effect chemical substances, and are safe to use. The coating has simple components, is easy to decompose and has no toxic or harmful effect on the environment.)

1. An egg preservative is characterized in that: the special coating is prepared from the following components in parts by mass:

20-30 parts of chitosan, 20-30 parts of clove water extract, 5-10 parts of NaCl, 20-30 parts of sodium alginate, 5-10 parts of lactic acid, 10-20 parts of fructus forsythiae essential oil and 1-5 parts of antibacterial peptide.

2. The egg preservative according to claim 1, wherein: the components can also comprise 5-10 parts of glycerin to increase the toughness of the preservative film.

3. The egg preservative according to claim 1, wherein: the antibacterial peptide in the components is obtained by fermenting enteromorpha with bacillus licheniformis and bifidobacterium.

4. A preparation method of an egg preservative is characterized by comprising the following steps: the method comprises the following steps:

step one, weighing 20-30 parts of sodium alginate, 10-20 parts of fructus forsythiae essential oil, 5-10 parts of glycerol and 1-5 parts of antibacterial peptide, and dissolving the components in 900mL of distilled water;

step two, weighing 5-10 parts of NaCl, and dissolving in the solution obtained in the step one;

weighing 20-30 parts of chitosan and 20-30 parts of clove water extract, grinding into powder, sieving with a 40-mesh sieve, and dissolving in 100mL of lactic acid solution containing 5-10 parts of the chitosan and the clove water extract;

and step four, mixing the solution obtained in the step three with the solution obtained in the step two, and decocting for 5-6 hours at 40-60 ℃, thus obtaining the preservative.

Technical Field

The invention belongs to the field of food preservation, and particularly relates to an egg preservative and a preparation method thereof.

Background

Eggs are food materials which are almost necessary for Chinese dining tables. However, as the storage time of the eggs is prolonged, the quality of the eggs is gradually reduced, and microorganisms can enter the eggs through the air holes on the eggshells, so that the nutritional value of the eggs is greatly reduced, and even the eggs are rotten. Coating preservation like melon and fruit is a common egg preservation method. Although the artificially synthesized chemical preservative can achieve a certain preservation purpose, the chemical preservative is extremely easy to produce toxic residues and harm human health. The main egg preservatives reported and researched at present are chitosan, polyvinyl alcohol, liquid paraffin and the like.

The chitosan has the functions of film forming and bacteriostasis, can form a layer of protective film on the surface of the egg and prevent microorganisms from entering the egg. The sodium alginate has excellent film forming property and antibacterial property, and the solution of the sodium alginate has good viscosity and gelling property. The chitosan and the sodium alginate are used together, so that the problem of poor film forming property of the chitosan when used singly can be solved.

Disclosure of Invention

The invention aims to provide an egg preservative and a preparation method thereof, and the aim of the invention is realized by the following technical scheme:

an egg preservative is prepared from the following components in parts by mass:

20-30 parts of chitosan, 20-30 parts of clove water extract, 5-10 parts of NaCl, 20-30 parts of sodium alginate, 5-10 parts of lactic acid, 10-20 parts of fructus forsythiae essential oil and 1-5 parts of antibacterial peptide.

Furthermore, the components can also comprise 5-10 parts of glycerin, so that the toughness of the preservative film is improved.

Further, the antibacterial peptide in the components is obtained by fermenting enteromorpha with bacillus licheniformis and bifidobacterium together.

A preparation method of an egg preservative comprises the following steps:

step one, weighing 20-30 parts of sodium alginate, 10-20 parts of fructus forsythiae essential oil, 5-10 parts of glycerol and 1-5 parts of antibacterial peptide, and dissolving the components in 900mL of distilled water;

step two, weighing 5-10 parts of NaCl, and dissolving in the solution obtained in the step one;

weighing 20-30 parts of chitosan and 20-30 parts of clove water extract, grinding into powder, sieving with a 40-mesh sieve, and dissolving in 100mL of lactic acid solution containing 5-10 parts of the chitosan and the clove water extract;

and step four, mixing the solution obtained in the step three with the solution obtained in the step two, and decocting for 5-6 hours at 40-60 ℃, thus obtaining the preservative.

Compared with the prior art, the invention has the following advantages:

1. the raw materials have wide sources, the operation is simple, and the bacteriostatic and fresh-keeping effects are good.

2. The raw materials are all natural components, do not contain toxic or side effect chemical substances, and are safe to use.

3. The coating has simple components, is easy to decompose and has no toxic or harmful effect on the environment.

Drawings

FIG. 1 is a schematic diagram showing the effect of different treatment methods on the moisture content of eggs in an experimental example;

FIG. 2 is a graph showing the effect of different storage methods on the yolk index of eggs in an experimental example;

FIG. 3 is a schematic diagram showing the effect of different treatment methods on the Hough units of eggs in an experimental example;

FIG. 4 is a graph showing the effect of different treatment methods on the colony count of eggs in the experimental examples.

Detailed Description

The present invention will be described in detail with reference to examples, experimental examples and tables.

Example 1

The invention provides an egg preservative which is prepared from the following components, by mass, 20-30 parts of chitosan, 20-30 parts of clove water extract, 5-10 parts of NaCl, 20-30 parts of sodium alginate, 5-10 parts of lactic acid, 5-10 parts of glycerol, 10-20 parts of fructus forsythiae essential oil and 1-5 parts of antibacterial peptide.

As a preferred embodiment of the method of the present invention,

the invention provides an egg preservative which is prepared from the following components, by mass, 20 parts of chitosan, 20 parts of clove water extract, 5 parts of NaCl, 20 parts of sodium alginate, 5 parts of lactic acid, 5 parts of glycerol, 10 parts of fructus forsythiae essential oil and 1 part of antibacterial peptide.

As a preferred embodiment of the method of the present invention,

the invention provides an egg preservative which is prepared from the following components, by mass, 30 parts of chitosan, 30 parts of clove water extract, 10 parts of NaCl, 30 parts of sodium alginate, 10 parts of lactic acid, 10 parts of glycerol, 20 parts of fructus forsythiae essential oil and 5 parts of antibacterial peptide.

Example 2

The present embodiment provides a method for preparing an egg preservative based on example 1:

weighing 20-30 parts of sodium alginate, 10-20 parts of fructus forsythiae essential oil, 5-10 parts of glycerol and 1-5 parts of antibacterial peptide, and dissolving the materials in 900mL of distilled water;

step two, weighing 5-10 parts of NaCl, and dissolving in the solution obtained in the step one;

weighing 20-30 parts of chitosan and 20-30 parts of clove water extract, grinding into powder, sieving with a 40-mesh sieve, and dissolving in 100mL of lactic acid solution containing 5-10 parts of the chitosan and the clove water extract;

and step four, mixing the solution obtained in the step three with the solution obtained in the step two, and decocting for 5-6 hours at 40-60 ℃ to obtain the preservative.

In the third step, the preferred dissolving temperature is 30-40 ℃, and the stirring speed is 100-150 rpm.

Example 3

This example is a preferred embodiment based on examples 1-2:

step one, weighing 20 parts of sodium alginate, 10 parts of fructus forsythiae essential oil, 5 parts of glycerol and 1 part of antibacterial peptide, and dissolving the components in 900mL of distilled water;

step two, weighing 5 parts of NaCl, and dissolving in the solution obtained in the step one;

weighing 20 parts of chitosan and 20 parts of clove water extract, grinding into powder, sieving with a 40-mesh sieve, and dissolving in 100mL of lactic acid solution containing 5 parts of chitosan and clove water extract;

and step four, mixing the solution obtained in the step three with the solution obtained in the step two, and decocting for 5 hours at 40-60 ℃ to obtain the preservative.

In the third step, the preferred dissolution temperature is 30 ℃ and the stirring speed is 100 rpm.

Example 4

This example is a preferred embodiment based on examples 1 to 3:

step one, weighing 30 parts of sodium alginate, 20 parts of fructus forsythiae essential oil, 10 parts of glycerol and 5 parts of antibacterial peptide, and dissolving the components in 900mL of distilled water;

step two, weighing 10 parts of NaCl, and dissolving in the solution obtained in the step one;

weighing 30 parts of chitosan and 30 parts of clove water extract, grinding into powder, sieving with a 40-mesh sieve, and dissolving in 100mL of lactic acid solution containing 10 parts;

and step four, mixing the solution obtained in the step three with the solution obtained in the step two, and decocting for 6 hours at the temperature of 60 ℃ to obtain the preservative.

In the third step, the preferred dissolution temperature is 40 ℃ and the stirring speed is 150 rpm.

Experimental example 1

Selecting 80 fresh eggs with similar specifications and sizes on the same day, cleaning impurities on the eggshells with clear water, airing, and randomly extracting 10 eggs to determine the yolk index, the Hough unit, the water content and the total number of bacterial colonies. The remaining 70 eggs are randomly divided into 2 groups, each group comprises 35 eggs, the eggs are respectively put into the prepared antistaling agent and distilled water for soaking for 1min, and then the eggs are fished out and drained. The drained eggs and the eggs of the control group are numbered and weighed in sequence, and stored in a storage cabinet with the temperature of 20 ℃ and the relative humidity of 70 percent. The storage period of each group of eggs is 8 weeks, and the detection is carried out 1 time per week and 5 eggs are detected each time.

Detecting the index

1. Water content of egg

Moisture measurements were made with reference to the food national standard method. Breaking eggs, drying the eggs in a 105 ℃ oven for 2 hours, taking out the eggs, cooling, weighing, repeatedly drying until the mass difference between the front and the back is not more than 2mg, namely constant weight, and counting.

As can be seen from figure 1, the preservative obtained by the invention can obviously reduce the water loss of eggs. The sodium alginate contained in the invention contains a large amount of hydrophilic groups, can firmly lock water and is not easy to lose. The repulsion between carboxyl and carboxyl on sodium alginate makes the polymer chain extend to form large space network structure, and the water absorbing capacity is strengthened.

2. Influence of egg yolk index

The yolk index is one of important indexes reflecting the freshness of eggs, qualified eggs with the yolk index larger than 0.2 are obtained, and the yolk index of fresh eggs is larger than 0.3. The thickness and the diameter of the yolk are calculated by a vernier caliper, and the yolk index is obtained by dividing the thickness of the yolk by the diameter.

The yolk index of fresh eggs is about 0.45, and the yolk index of the eggs is reduced at a point along with the time, as can be seen from figure 2, the egg yolk index of the eggs using the preservative is obviously reduced at a slower speed, which shows that the preservative has good preservation performance, and the growth substances containing the bacteriostatic components in the preservative can inhibit the growth and reproduction of microorganisms inside and outside the eggs, so that the decomposition of the nutritional components in the egg yolk is slowed down.

Hough unit the height of the dense protein was measured with a vernier caliper and calculated to give Hough unit by the following formula:

HU＝100×lg[h+7.57-1.7×(w0.37)]

wherein: HU-Hough unit; h-height of protein on glass dish, mm; w is the quality of the eggs.

The Hough Unit (HU) is an important index for internationally evaluating the quality and freshness of eggs. HU value is defined as fresh egg at 70-100, and less than 40 indicates that the egg has deteriorated. As can be seen from FIG. 3, the time for storing the fresh eggs becomes shorter and shorter in the Hough index 83. The HU value of the eggs using the preservative prepared by the invention is reduced by a slower amplitude and speed than those of the eggs in a control group. The main reason for the decrease in HU is that the water content of egg white is constantly volatilized during storage, and a part of the water content is transferred to egg yolk. The lysozyme decomposes partial protein, so that the proportion of thin protein is increased, the coating film can slow down the volatilization of water, and the decomposition speed of thick protein, thereby slowing down the change of Hough unit.

Change in total number of colonies from egg

The broken eggs are diluted properly and the total number of colonies is determined by a plate counting method.

As can be seen from FIG. 4, at week 3, the total number of colonies in the control group started to rise significantly, mainly because the eggs contained a certain amount of lysozyme, and thus in the early stage of storage, the total number of colonies in the eggs was detected less, and with the time increase, the amount of concentrated protein decreased, the amount of lysozyme also decreased, and the interior microorganisms gradually propagated, and the eggs started to deteriorate. Over time, microorganisms in the air begin to penetrate into the eggs, causing mass propagation of the eggs. The egg using the preservative provided by the invention firstly forms a film on the outer surface of the egg, so that the loss of water in the egg can be prevented, meanwhile, microorganisms in the air are prevented from entering the egg, and effective components in the film, such as sodium alginate and the like, can permeate the egg, so that a certain inhibiting effect on the growth of the microorganisms in the egg is achieved.