阅读说明：本技术 一种冷冻大黄鱼品质保障方法及其应用 (Frozen large yellow croaker quality guarantee method and application thereof ) 是由 张宾 毛俊龙 于 2019-09-27 设计创作，主要内容包括：本发明属于海鲜保鲜技术领域。本发明公开了一种冷冻大黄鱼品质保障方法,其包括保鲜液配制、前处理、保鲜处理及贮藏,其中采用的保鲜液由茶黄素、石榴提取物、阿魏酸、海藻酸钠和生物保鲜剂与水混合后制得；本发明还公开了一种冷冻大黄鱼品质保障方法的应用,将其应用于长时间贮藏冷冻大黄鱼。本发明中,利用茶黄色、石榴多酚、阿魏酸和生物保鲜剂的抗氧化活性、抗菌抑菌活性和四者之间具有非常好的协同增效作用,用以保证大黄鱼冻藏品质；大黄鱼表面颜色偏黄色,茶黄素的使用并不影响产品外观,反而增强鱼体的颜色,保障产品冻藏品质,此外海藻酸钠赋予良好的成膜性,使保鲜液更易附着成膜,提高保鲜处理的效率和效果。(The invention belongs to the technical field of seafood preservation. The invention discloses a quality guarantee method for frozen large yellow croakers, which comprises the steps of preparation of a fresh-keeping solution, pretreatment, fresh-keeping treatment and storage, wherein the adopted fresh-keeping solution is prepared by mixing theaflavin, pomegranate extract, ferulic acid, sodium alginate, a biological fresh-keeping agent and water; the invention also discloses an application of the quality guarantee method of the frozen large yellow croaker, and the quality guarantee method is applied to long-time storage of the frozen large yellow croaker. According to the invention, the tea yellow color, the pomegranate polyphenol, the ferulic acid and the biological preservative have very good synergistic effect on the antioxidant activity, the antibacterial activity and the bacteriostatic activity of the four, so that the frozen storage quality of the large yellow croaker is ensured; the surface color of the large yellow croaker is yellow, the use of theaflavin does not affect the appearance of the product, but enhances the color of the fish body, ensures the frozen storage quality of the product, and in addition, sodium alginate has good film forming property, so that the fresh-keeping liquid is easier to adhere to form a film, and the efficiency and effect of the fresh-keeping treatment are improved.)

1. A quality guarantee method for frozen large yellow croakers is characterized by comprising the following steps:

a) preparing a fresh-keeping solution: preparing a fresh-keeping solution from 0.25-0.45 wt% of theaflavin, 0.15-0.30 wt% of pomegranate extract, 0.10-0.30 wt% of ferulic acid, 3-5 wt% of sodium alginate, 5-8 wt% of a biological fresh-keeping agent and the balance of water;

b) pretreatment: leaching fresh large yellow croaker with water;

c) fresh-keeping treatment: immersing the washed fresh large yellow croaker in a fresh-keeping solution, taking out the large yellow croaker for freezing treatment at the temperature of minus 35 ℃ and below, taking out the large yellow croaker for immersing treatment in the fresh-keeping solution, taking out the large yellow croaker for freezing treatment at the temperature of minus 35 ℃ and below, and finally taking out the large yellow croaker for immersing treatment in the fresh-keeping solution;

d) and (3) storage: storing the treated large yellow croaker at-18 deg.C or below for a long period.

2. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 1, wherein:

in the step c), the fresh-keeping treatment is specifically that the washed fresh large yellow croaker is immersed in the fresh-keeping liquid for 30-50 minutes, then taken out and frozen at-35 ℃ and below for 8-10 hours, then taken out and immersed in the fresh-keeping liquid for 8-15 seconds, taken out and frozen again at-35 ℃ and below for 1-2 hours, and finally taken out and immersed in the fresh-keeping liquid for 5-15 seconds.

3. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 1, wherein:

the biological preservative is prepared from large yellow croaker leftovers through enzymolysis, purification and Maillard reaction.

4. The method for guaranteeing the quality of frozen large yellow croaker according to any one of claims 1 or 3, wherein:

the preparation method of the biological preservative comprises the following steps,

firstly, adding water into large yellow croaker leftovers, crushing to obtain homogenate, drying the homogenate to obtain homogenate powder, then drying and crushing the homogenate powder to obtain homogenate micro powder, adding the homogenate micro powder into water, uniformly mixing, and standing to obtain a mixed solution;

secondly, adding protease which accounts for 0.5-2.0 wt% of the weight of the mixed solution into the mixed solution, uniformly mixing, performing enzymolysis treatment, and then inactivating enzyme to obtain an enzymolysis solution;

thirdly, cooling the enzymatic hydrolysate, centrifuging and taking supernatant, adding trichloroacetic acid solution into the supernatant, standing, centrifuging and taking the supernatant as polypeptide solution;

and fourthly, adding maltose into the polypeptide solution, uniformly mixing, reacting for 2.5-4 hours in a heating and pressurizing environment, and cooling to obtain the biological preservative.

5. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 4, wherein:

the first step is specifically that the large yellow croaker leftovers are added with water in an amount which is 2-2.5 times the weight of the large yellow croaker leftovers and are crushed to prepare homogenate, the homogenate is dried to prepare homogenate powder, the homogenate powder is dry-ground and crushed and is sieved by a 200-250-mesh sieve to prepare homogenate micro powder, and the homogenate micro powder is added into water in an amount which is 3-4 times the weight of the homogenate micro powder to be uniformly mixed and is stirred for 1-1.5 hours to prepare mixed liquid.

6. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 4, wherein:

and step two, adding protease accounting for 0.5-2.0 wt% of the mixed solution into the mixed solution, uniformly mixing, performing enzymolysis for 3-6 hours at 45-60 ℃, and then inactivating the enzyme to obtain an enzymolysis solution.

7. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 6, wherein:

the protease is prepared from trypsin, flavourzyme and papain in a weight ratio of 1: (1.5-2.5): (0.7-1.1).

8. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 4, wherein:

and step three, specifically, cooling the enzymatic hydrolysate, centrifuging, taking supernatant, adding an isovolumetric trichloroacetic acid solution with the mass content of 15% into the supernatant, standing for 30-60 minutes, centrifuging, and taking the supernatant as a polypeptide solution.

9. The method for guaranteeing the quality of the frozen large yellow croaker according to claim 4, wherein:

and step four, specifically, adding maltose accounting for 2-5 wt% of the polypeptide solution into the polypeptide solution, uniformly mixing, reacting for 2.5-4 hours at 76-84 ℃ under the pressure of 1.2-1.4 atm, and cooling to obtain the biological preservative.

10. The application of the method for guaranteeing the quality of the frozen large yellow croaker according to any one of claims 1 to 9, wherein the method comprises the following steps:

it can be used for long-term storage of frozen Pseudosciaena crocea.

Technical Field

The invention relates to the technical field of seafood preservation, in particular to a quality guarantee method for frozen large yellow croakers and application thereof.

Background

The large yellow croaker is an important economic fish in Zhejiang, and the activity of the endogenous enzyme of the large yellow croaker is strong, so that some proteins and unsaturated fatty acids in the fish are easy to be oxidized, thereby delaying the reproduction of fish microorganisms and inhibiting the activity of the endogenous enzyme of the fish. Although partial enzyme activity in the fish meat can be passivated by low-temperature frozen storage, the phenomenon of fish meat quality deterioration still commonly occurs in the long-term frozen storage process.

Disclosure of Invention

In order to solve the problems, the invention provides a frozen large yellow croaker quality guarantee method which can delay the propagation of microorganisms in the large yellow croaker, inhibit the activity of endogenous enzymes in the large yellow croaker and guarantee the frozen preservation quality of the large yellow croaker;

the invention also discloses an application of the quality guarantee method for the frozen large yellow croaker.

A quality guarantee method for frozen large yellow croakers comprises the following steps:

a) preparing a fresh-keeping solution: preparing a fresh-keeping solution from 0.25-0.45 wt% of theaflavin, 0.15-0.30 wt% of pomegranate extract, 0.10-0.30 wt% of ferulic acid, 3-5 wt% of sodium alginate, 5-8 wt% of a biological fresh-keeping agent and the balance of water;

b) pretreatment: leaching fresh large yellow croaker with water;

c) fresh-keeping treatment: immersing the washed fresh large yellow croaker in a fresh-keeping solution, taking out the large yellow croaker for freezing treatment at the temperature of minus 35 ℃ and below, taking out the large yellow croaker for immersing treatment in the fresh-keeping solution, taking out the large yellow croaker for freezing treatment at the temperature of minus 35 ℃ and below, and finally taking out the large yellow croaker for immersing treatment in the fresh-keeping solution;

d) and (3) storage: storing the treated large yellow croaker at-18 deg.C or below for a long period.

In the treatment method, firstly, the preservation solution which is mainly composed of theaflavin, pomegranate extract, ferulic acid and a biological preservative is adopted, and secondly, the preservation solution is subjected to multiple times of immersion and freezing treatment during the treatment of the preservation solution, so that the preservation solution can form uniform and firm ice coats on the surfaces of the large yellow croakers; the theaflavin is a golden yellow pigment existing in yellow tea and black tea, is a product of tea fermentation, has good antioxidant activity, and can enhance the body color of the large yellow croaker body and ensure the frozen storage quality because the surface color of the large yellow croaker is yellow and the appearance of the large yellow croaker is not affected by the use of the theaflavin; the pomegranate extract contains abundant pomegranate polyphenols, and also has strong antioxidant activity; ferulic acid has the functions of eliminating free radicals and promoting the generation of enzymes for eliminating the free radicals, and also has strong antioxidant activity; the biological preservative is prepared from large yellow croaker leftovers through enzymolysis and Maillard reaction purification, has safe and reliable sources, can improve the use of large yellow croaker processing waste, reduces waste, and has good antibacterial and bacteriostatic functions; the theaflavin, the pomegranate extract, the ferulic acid and the biological preservative take effect synergistically, so that the effects of antioxidation, antibiosis and bacteriostasis can be better achieved, the activity of endogenous enzymes in the fish meat of the large yellow croaker is reduced, the oxidation change of proteins and unsaturated fatty acids in the fish meat is slowed down, the propagation of microorganisms in the fish meat is slowed down, and the process of deterioration of the fish meat quality of the large yellow croaker is greatly slowed down in the process of freezing and storing.

Preferably, the pomegranate polyphenol content in the pomegranate extract is 40-50 wt%.

Preferably, in the step c), the fresh-keeping treatment is specifically that the washed fresh large yellow croaker is immersed in the fresh-keeping solution for 30-50 minutes, then taken out and frozen at-35 ℃ and below for 8-10 hours, then taken out and immersed in the fresh-keeping solution for 8-15 seconds, taken out and frozen again at-35 ℃ and below for 1-2 hours, and finally taken out and immersed in the fresh-keeping solution for 5-15 seconds.

Preferably, the biological preservative is prepared from large yellow croaker leftovers through enzymolysis, purification and Maillard reaction.

Preferably, the preparation method of the biological preservative is as follows,

firstly, adding water into large yellow croaker leftovers, crushing to obtain homogenate, drying the homogenate to obtain homogenate powder, then drying and crushing the homogenate powder to obtain homogenate micro powder, adding the homogenate micro powder into water, uniformly mixing, and standing to obtain a mixed solution;

secondly, adding protease which accounts for 0.5-2.0 wt% of the weight of the mixed solution into the mixed solution, uniformly mixing, performing enzymolysis treatment, and then inactivating enzyme to obtain an enzymolysis solution;

thirdly, cooling the enzymatic hydrolysate, centrifuging and taking supernatant, adding trichloroacetic acid solution into the supernatant, standing, centrifuging and taking the supernatant as polypeptide solution;

and fourthly, adding maltose into the polypeptide solution, uniformly mixing, reacting for 2.5-4 hours in a heating and pressurizing environment, and cooling to obtain the biological preservative.

Preferably, the first step is to increase the large yellow croaker leftovers by 2-2.5 times of water by weight, grind the large yellow croaker leftovers to prepare homogenate, dry the homogenate to prepare homogenate powder, dry grind the homogenate powder, grind and grind the homogenate powder, screen the homogenate powder by a 200-250 mesh sieve to prepare homogenate micro powder, add the homogenate micro powder into 3-4 times of water by weight, mix the homogenate micro powder uniformly and stir the mixture for 1-1.5 hours to prepare the mixed solution.

Preferably, step two, specifically, adding protease with the weight of 0.5-2.0 wt% of the mixed solution into the mixed solution, uniformly mixing, performing enzymolysis at 45-60 ℃ for 3-6 hours, and then inactivating the enzyme to obtain the enzymatic hydrolysate.

Preferably, the protease is a mixture of trypsin, flavourzyme and papain in a weight ratio of 1: (1.5-2): (0.8-1.1).

Preferably, in the third step, the enzymatic hydrolysate is cooled and then centrifuged, the supernatant is taken, an isometric trichloroacetic acid solution with the mass content of 15% is added into the supernatant, the supernatant is taken as the polypeptide solution after the centrifugation after the standing for 30 to 60 minutes.

Preferably, step four, specifically, adding maltose accounting for 2-5 wt% of the polypeptide solution into the polypeptide solution, uniformly mixing, reacting at 76-84 ℃ under 1.2-1.4 atm for 2.5-4 hours, and cooling to obtain the biological preservative.

In the preparation process of the biological preservative, the leftovers of the large yellow croaker are firstly added with water and crushed, then the leftovers of the large yellow croaker are dried and ground in a dry grinding way, so that the components of the leftovers of the large yellow croaker in the obtained mixed solution can be distributed more uniformly as much as possible, the particles are finer, the subsequent enzymolysis process is facilitated, the enzymolysis adopts compound protease, the enzymolysis efficiency can be improved, and the efficient and stable operation of the enzymolysis process can be ensured; then, purifying the polypeptide after enzymolysis to remove inactive or low-activity components and improve the purity of the active peptide; and then, Maillard reaction is carried out on the purified active peptide, so that the fishy smell of the large yellow croaker leftovers can be removed, and the antibacterial and antioxidant activity of the product can be improved, so that the fresh-keeping effect is better.

An application of frozen large yellow croaker in long-term storage is disclosed.

Therefore, the invention has the following beneficial effects: according to the invention, the tea yellow color, the pomegranate polyphenol, the ferulic acid and the biological preservative have very good synergistic effect on the antioxidant activity, the antibacterial activity and the bacteriostatic activity of the four, so that the frozen storage quality of the large yellow croaker is ensured; the surface color of the large yellow croaker is yellow, the use of theaflavin does not affect the appearance of the product, but enhances the color of the fish body, ensures the frozen storage quality of the product, and in addition, sodium alginate has good film forming property, so that the fresh-keeping liquid is easier to adhere to form a film, and the efficiency and effect of the fresh-keeping treatment are improved.

Detailed Description

The technical solution of the present invention will be further described with reference to the following embodiments.

It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present invention, all the equipments and materials are commercially available or commonly used in the industry, and the methods in the following examples are conventional in the art unless otherwise specified.