KR100693803B1 - Egg preserving agent using the chitosan and producing method thereof - Google Patents

Abstract

A method of manufacturing an egg preservative by decalcifying a crustacean's shell with HCl, deproteinizing with NaOH, depigmenting with NaOCl and deacetylating with NaOH is provided. The method simplifies manufacturing process. The chitosan solution obtained is diluted with acetic acid solutions and coated on eggs. A crustacean's shell as a raw material is mixed with HCl in a ratio of 1:15(w/v), reacted for 30min, added with the weight of 3% NaOH solution ten times as much as the raw material and reacted for 5min. The deproteinized raw material is reacted with the weight of 10% NaOCl solution ten times as much as deproteinized raw material for 5min, added 45% NaOH and deacetylated ten times as much as the decolored material for 30min to obtain chitosan. The chitosan obtained is diluted with 1% acetic acid solutions.

Description

Egg preserving agent using the chitosan and manufacturing method

The present invention relates to an egg preservative using chitosan and a method for manufacturing the same, and more particularly, to prepare a new functional chitosan by reducing the production cost by simplifying the conventional process in the production of chitosan from crab shell and coating it on the egg The present invention relates to an egg preservative using chitosan and a method for producing the same, which significantly improve the shelf life.

The annual amount of crustaceans produced in Gyeongsangbuk-do is about 10,094 tons, making it the largest producer in the nation. However, wastes (70-80% of crustaceans) that are discarded after recovering meat from these crustaceans are a major environmental pollutant when left, so it is urgent to find new ways to recycle them.

On the other hand, chitosan is a natural high molecular material that is deacetylated by treating chitin in shellfish such as crabs and shrimps with high temperature and strong alkali. Available in various concentrations, the global market for chitin / chitosan in 2005 is estimated at approximately $ 1.9 billion. Chitosan is used as a coagulant, binder, stabilizer, cholesterol lowering agent, and antimicrobial agent in the food sector (2005 global demand market: US $ 30 million). Especially, chitosan has high antibacterial activity against decaying microorganisms. It is reported to be effective in improving shelf life of various foods such as sausage. In addition, chitosan has a property of forming a film, and has been reported to extend shelf life when coated with fruits, vegetables, fish, eggs, and the like.

Crustacean waste consists mainly of 30-40% protein, 30-50% calcium carbonate, small amounts of carotenoids and 20-30% chitin. Therefore, in order to separate chitin from these crustacean wastes, protein is removed (deprotein) with dilute alkaline solution, calcium is removed with dilute acid (decalcium), and then pigments are removed using an organic solvent or an oxidizing agent (depigmentation). ) Is going through the process. On the other hand, to prepare chitosan (deacetylated chitin) from chitin is deacetylated by treating with strong alkali (50%) for a long time (3 to 5 hours) at a high temperature of 100 ° C or higher.

Chitosan, which is currently produced domestically and internationally, is manufactured from these crab or shrimp shells through these four processes, resulting in high production costs of chitosan due to the enormous chemicals, energy costs, and wastewater treatment costs. Its use in a wider field is quite limited.

However, the protein present in crustaceans in the production of chitosan from crustaceans is considered to be removed by strong alkali treatment in the deacetylation process even though the deproteinization process is not carried out, but no specific research results have been reported. In addition, chitosan combined with calcium produced without decalcination in the production of chitosan from crustaceans is considered to be used as a new functional material, but there is no research on this.

Eggs, on the other hand, are an excellent source of high quality protein and various vitamins and minerals, which have long been consumed as a major decay in our daily lives. However, the quality of the egg is relatively unstable and may cause various problems such as weight loss, internal quality degradation, and microbial contamination. Transfer of carbon dioxide and water through eggshells during storage results in poor egg white and egg yolk quality and weight loss. Some microorganisms can penetrate inside eggs and contaminate their contents. In order to solve this problem, many researchers have been interested in the development of various synthetic polymers, polysaccharides, proteins, and oils-derived coatings, but there are no commercial applications.

Accordingly, it is an object of the present invention to provide a coating agent for producing new functional chitosan with reduced production cost by simplifying a conventional process in manufacturing chitosan from crab shells and improving the preservation of eggs using the same.

Egg preservative using chitosan of the present invention for achieving the above object;

(1) In the production of chitosan by shells of crustaceans such as crabs, shrimps and crayfish according to a conventional method, the decalcification reaction with HCl and the deproteination reaction with NaOH are 20-30 minutes and 0-15 minutes, respectively. Performing chitosan to obtain; And

(2) It is characterized in that the chitosan obtained in step (1) is an egg preservative made of a chitosan solution by diluting it in an acetic acid solution.

According to another configuration of the invention, the chitosan is characterized in that diluted to a concentration of 2% (W / V) in 1% acetic acid solution.

According to another configuration of the present invention, it is characterized by providing an egg with improved shelf life coated with the chitosan solution of the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited thereto.

Examples 1-7

Preparation of Chitosan

The dried crab (Chionoecetes opilio) leg shell used in this study was purchased from Kumho Hwaseong Co., Ltd. located in Uljin-gun, Gyeongbuk. The dried shells were ground with a mill (Wiley mill; model 4, Thomas Scientific, Swedesboro, NJ, USA) and then 10- (2.00 mm), 20- (0.841 mm), 40- (0.425 mm), 60-mesh ( 0.250 mm) was divided into particles by the size of the particles, of which only 0.841-0.425 mm particles were used for chitosan production. The chitosan particles were decalcified (DM) with 1 N HCl in a ratio of crab shell: solvent of 1:15 (w / v) at a convection temperature for the same time as in Table 1 below.

The calcium removed from the decalcification reaction was vacuum filtered using Whatman No. 4 filter paper, and the residue was washed with water sufficiently and washed again with distilled water to remove excess water. Vacuum filtered. Deprotein (DP) is added to 3% NaOH solution corresponding to 10 times the weight of the raw material (w / v) and reacted at 15 psi / 121 ℃ 0, 5, or 15 minutes as shown in Table 1 as described above It washed with water and filtered. Depigmentation was performed by adding 10% NaOCl solution corresponding to 10 times the weight of the raw material (w / v), stirring for 5 minutes at room temperature, washing with water, filtration, and drying for 4 hours at 60 ° C. in a forced-air oven. . Deacetylation was performed by adding 45% NaOH solution corresponding to 10 times (w / v) of raw material to chitin and reacting at 15 psi / 121 ° C for 30 minutes, followed by washing, filtration and 60 ° C in a forced-air oven. Dried at 4 h.

 TABLE 1

division DM processing time (minutes) DP processing time (minutes) Example 1 30 0 Example 2 30 5 Example 3 30 15 Example 4 20 15 Example 5 10 15 Example 6 0 15 Example 7 0 0

As described above, chitosan according to the present invention of Examples 1 to 7 was prepared, respectively.

Examples 8-14

Preparation of Chitosan Solution

In the chitosan solution according to the present invention, the chitosan solutions of Examples 8 to 14 were prepared at concentrations of 2% (W / V) in each of the chitosan prepared according to Examples 1 to 7 in 1% acetic acid solution.

Experimental Example 1

Chitosan Ingredient Analysis

Moisture and ash content for each chitosan prepared according to Examples 1 to 7 were determined by standard methods 930.15 and 942.05, respectively (AOAC, Official Methods of Analysis , 15th edn, Association of Official Analytical Chemists, Arlington, VA, USA, pp 69-70 (1990)) and nitrogen was analyzed using an elemental analyzer (EA 1110, CE Instrument, Rodano-Milan, Italy) and the results are shown in Table 2 below.

In addition, the degree of deacetylation (DD) was measured by a colloid titration method using N / 400 potassium polyvinyl sulfate (f = 1.005, Wako Pure Chemical, Osaka, Japan), and the viscosity was carried out in a 1% acetic acid solution. The chitosan prepared according to Examples 1 to 7 was dissolved at a concentration of 1% and measured at 25 ± 0.3 ° C using a Brookfield viscometer (Brookfield viscometer, model LVDV-II +; Brookfield Engineering Labs., Stoughton, MA). It is expressed in centipoise (cP). The solubility percentage was dissolved in 0.5% chitosan concentration in 1% acetic acid solution and the results are shown in Table 2. Herein, all the analysis values of this experiment example and the analysis values of the following experimental example are expressed as the mean value or the mean ± standard deviation measured three times or ten times, respectively, and the significance between the means (P <0.05) was SPSS ( Statistical Package for Social Sciences, SPSS Inc., Chicago, IL) software package was tested by Duncan's multiple range test.

 TABLE 2

Experimental Example 2

Chitosan solutions prepared according to Examples 8-14 were coated on eggs. That is, for the coating of eggs, using a sponge brush (sponge brush) evenly applied to the chitosan solution on the egg surface, and blow dry with a cold wind fan. As a control, uncoated eggs (control 1) and eggs coated with 1% (v / v) acetic acid solution (control 2) were used. The control and the chitosan solution-coated eggs were placed in a cardboard egg plate and then stored in a 25 ° C. incubator for 5 weeks, and 10 eggs were taken per treatment section each week to investigate the quality change of the following items.

1.Vibration and before and after coating Eggshell  Measurement of thickness

The weight of the eggs before and after coating with the chitosan solution according to Example 8 was measured by an electronic balance (GT 480, Ohaus Corp., Florham Park, NJ, USA), and the eggshell thickness was measured by a pocket thickness measure (Model 25M-). 5, Ames Inc., Melrose, MA, USA) and the results are shown in Table 3 below.

 TABLE 3

Comparison of egg weight and eggshell thickness before and after chitosan coating

Egg weight (g) ¹ Eggshell Thickness (mm) ¹ Before coating 54.58 ± 1.85 0.36 ± 0.03 After coating 54.59 ± 1.84 0.36 ± 0.02

As can be seen in Table 3, the thickness of the eggplant and eggshell before the chitosan coating was 54.58g and 0.36mm, respectively, and there was no difference between the eggshell and eggshell thickness of 54.59g and 0.36mm after the chitosan coating. Therefore, it can be seen that the chitosan coating does not affect the egg weight and eggshell thickness.

2. Measurement of the reduction rate

Eggs coated with the control (untreated and 1% acetic acid coating) and chitosan solutions according to Examples 8 to 14 were stored at 25 ° C. for 5 weeks, and the eggs were weighed to obtain egg yolk reduction as a percentage of the initial weight. Table 4 shows.

 TABLE 4

Percent reduction in egg weight during 5 weeks storage of chitosan coated eggs at 25 ° C ¹

coating 1 week 2 weeks 3 weeks 4 Weeks 5 Weeks Control No treatment   2.18   3.94   6.28   8.59  10.45 1% acetic acid   2.21   4.01   6.24   9.12  11.27 Chitosan solution Example 8   2.07   3.55   5.19   7.76   8.57 Example 9   1.93   3.55   5.48   6.86   9.79 Example 10   1.92   4.01   5.83   7.28   8.83 Example 11   1.90   3.24   6.01   7.31   9.53 Example 12   2.02   3.72   5.94   7.96   9.37 Example 13   2.50   4.35   6.50   8.45  11.52 Example 14   2.21   3.76   6.06   8.67  10.51

As shown in Table 4, the control and egg-coated eggs of the chitosan solution of Examples 8 to 14 increased as the storage period increased, and after 5 weeks, the reduction rate ranged from 8.57% to 11.52%. However, there was no difference in egg weight reduction between untreated and 1% acetic acid coated eggs during storage for 5 weeks. Although the coating effect of the chitosan solution of Examples 8-11 with respect to the egg-reducing rate differs slightly according to the kind of chitosan, the effect was recognized after two weeks. On the other hand, the egg coated with the chitosan solution of Examples 12 to 14 was almost similar to the untreated bulb and the egg reduction rate was hardly found chitosan coating effect. Egg yolk reduction occurs when the contents of the egg during storage are evaporated through the eggshell and the pores of the egg shell, and the chitosan treatment effect on the egg surface seals the pores on the egg surface to prevent evaporation of CO ₂ or moisture inside the egg, thereby reducing egg yolk. It seems to be due to the blocking action.

3. Haugh  unit and yolk index measurement

Eggs were placed on a horizontal glass plate to measure egg white and egg yolk using a tripod micrometer (Model S? 6428, BC Ames Inc., Melrose, MA, USA) and a digital caliper (CD-20B, Mitutoyo, Japan). The yolk width was measured. Haugh unit was calculated by using Haugh unit calculator which converts egg weight and egg white value into Haugh unit, and yolk index value was calculated by the ratio of egg yolk height / yolk width (Lee SH, No HK, Jeong YH. 1996. Effect of chitosan coating on quality of egg during storage.J Korean Soc Food Nutr 25: 288-93).

In detail, the Haugh unit is a comprehensive measure of egg quality that measures egg weight and egg whites. The eggs treated with the chitosan solution according to each control and Example were stored for 5 weeks at 25 ° C. to measure the change in Haugh unit and the results are shown in Table 5 below.

As can be seen from Table 5, the overall Haugh unit decreased with the storage period, and similarly decreased between the untreated and 1% acetic acid coated eggs for 5 weeks. Eggs coated with the chitosan solution of Examples 8-11 showed a higher Haugh unit compared to the untreated, whereas eggs coated with the chitosan solution of Examples 13-14 were similar to the untreated.

 TABLE 5

Haugh unit changes during 5 weeks storage of chitosan coated eggs at 25 ° C

coating Week 0 1 week 2 weeks 3 weeks 4 Weeks 5 Weeks Control No treatment   99.1 67.8 54.5 49.6 49.0 44.5 1% acetic acid   99.1 68.2 59.8 52.7 44.4 35.7 Chitosan ² Example 8   99.1 77.2 70.0 63.3 58.4 56.6 Example 9   99.1 78.5 70.0 69.0 60.2 61.5 Example 10   99.1 74.6 69.5 59.3 53.7 57.1 Example 11   99.1 81.6 69.7 58.4 58.1 58.9 Example 12   99.1 76.5 68.8 53.4 47.5 45.8 Example 13   99.1 66.4 54.2 49.4 45.6 42.1 Example 14   99.1 70.5 56.4 56.2 45.8 38.6

From the above results, the quality preservation effect of the egg by the coating of the chitosan solution of Examples 8 to 11 during the storage period was clear, and it can be seen that the effect has a preservation effect for at least 3 weeks compared to the untreated.

In addition, as described above, the value obtained by dividing the height of the yolk by the diameter of the yolk is called a yolk index and is used to evaluate the freshness of the yolk. The decrease in yolk index during storage is due to the weakening of the yolk sac. During storage, the yolk index is transferred to the yolk sac through the yolk sac, resulting in lower yolk height and larger diameter. The longer the storage period and the higher the storage temperature, the faster the moisture transfer and eventually the egg yolk ruptures, resulting in a mixture of egg yolk and egg white (Obanu ZA, Mpieri AA. 1984. Efficiency of dietary vegetable oils in preserving the quality of shell eggs under ambient tropical conditions.J Sci Food Agric 35: 1311-17). Eggs coated with chitosan solution according to each control and Example were stored for 5 weeks at 25 ° C. to measure yolk index change and the results are shown in Table 6 below.

As can be seen in Table 6, both control and chitosan coated eggs decreased yolk index values as the storage period increased. After 5 weeks of storage, the yolk index value of the untreated group decreased from 0.48 at initial storage to 0.24, and the 1% acetic acid-coated egg decreased to 0.21, which is the yolk index value after 5 weeks of the eggs coated with the chitosan solution of Examples 12-14. Similar to 0.21-0.24. On the other hand, the eggs coated with the chitosan solution of Examples 8 to 11 showed a significantly high yolk index value (0.27-0.32) even after 5 weeks.

The yolk index value after 5 weeks of the eggs coated with the chitosan solution of Examples 8 to 11 was 0.27-0.32, which is similar to or higher than the yolk index value of 0.28 after 3 weeks of the untreated, the coating of the chitosan solution of Examples 8 to 11 The quality preservation effect of the egg was clear, and the effect was found to have a preservation effect for at least two weeks compared to the untreated.

 TABLE 6

Changes in Yolk Index during Chitosan Coated Eggs at 25 ° C for 5 Weeks

coating Week 0 1 week 2 weeks 3 weeks 4 Weeks 5 Weeks Control No treatment 0.48 0.42 0.33 0.28 0.25 0.24 1% acetic acid 0.48 0.41 0.36 0.30 0.25 0.21 Chitosan Example 8 0.48 0.42 0.40 0.34 0.30 0.27 Example 9 0.48 0.43 0.42 0.37 0.33 0.32 Example 10 0.48 0.42 0.39 0.33 0.29 0.28 Example 11 0.48 0.42 0.40 0.34 0.33 0.29 Example 12 0.48 0.42 0.41 0.30 0.29 0.24 Example 13 0.48 0.38 0.34 0.29 0.24 0.21 Example 14 0.48 0.40 0.35 0.29 0.25 0.21

Experimental Example 3

Changes in Egg Grade During Storage

Egg grades are divided into AA (72 or more), A (60-71), B (31-59), and C (30 or less) based on the Haugh unit of Experimental Example 2 according to the USDA standard. Lee SH, No HK, Jeong YH. 1996. Effect of chitosan coating on quality of egg during storage.J Korean Soc Food Nutr 25: 288-93.). The results of measuring the grade change of eggs using Haugh unit during storage are shown in Table 7 below.

 TABLE 7

Grade change during 10 weeks chitosan coated eggs at 25 ° C for 5 weeks

coating Week 0 1 week 2 weeks 3 weeks 4 Weeks 5 Weeks AA AA A B AA A B AA A B C AA A B C AA A B C Control No treatment 10  3 6 1      1 9         10      1 9          7 3 1% acetic acid 10  3 5 2      6 4         10          9 1          6 4 Chitosan Example 8 10  7 3  3 6 1  2 3 5  1 3 6  1 3 6 Example 9 10  8 2  3 7  4 4 2  2 2 6  3 3 4 Example 10 10  7 3  5 3 2  1 4 5  1 2 7  1 5 4 Example 11 10  8 2  6 3 1  1 3 6  1 5 4  1 4 4 1 Example 12 10  8 2  3 6 1      2 8      2 7 1      1 9 Example 13 10  1 8 1      3 7      1 8 1          10          8 2 Example 14 10  3 7      5 5      3 7      1 7 2          7 3

The grade of the egg gradually decreased with the storage period, and the grade reduction pattern of the control and the egg coated with the chitosan solution of Examples 13 to 14 was similar. Eggs from all controls and eggs coated with the chitosan solutions of Examples 13-14 were lowered to B and C grades after 5 weeks of storage at the initial AA grade of storage. On the other hand, the eggs coated with the chitosan solution of Examples 8 to 11 showed distribution of AA grade 10-30%, Grade A 30-50%, Grade B 40-60% after 5 weeks at the initial AA grade 100%. . From these results, it can be seen that the quality preservation effect of the eggs by coating with the chitosan solution of Examples 8 to 11 is clear.

The egg preservative using the chitosan of the present invention and a method for manufacturing the same, which are configured as described above, provide a new functional chitosan with reduced production costs by simplifying the conventional process when preparing chitosan from crab shell, and coating the egg using the same. It is an excellent invention which greatly improves preservability.

Claims (3)

Hydrochloric acid (HCl) was added to the crustacean shell material in a ratio of 1:15 (w / v) crustacean shell: hydrochloric acid, followed by decalcification for 30 minutes, and then 10 times (w / v) 3% sodium hydroxide (NaOH) solution corresponding to deproteinization reaction for 5 minutes, and then 10% sodium hypochlorite (NaOCl) corresponding to 10 times (w / v) the weight of the deproteination raw material. Solution was added for 5 minutes, and then deacetylation was performed for 30 minutes by adding 45% sodium hydroxide (NaOH) corresponding to 10 times (w / v) the weight of the depigmented raw material. Thereby preparing chitosan; And The method for preparing an egg preservative using chitosan, comprising diluting the chitosan prepared in the step to a concentration of 2% (w / v) in a 1% acetic acid solution. Egg preservative using chitosan produced using the manufacturing method of claim 1. delete