JP3001893B2 - Fresh seafood freshness preserving agent and method of preserving freshness - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a freshness-maintaining agent and a freshness-maintaining method that maintain the freshness of fish and shellfish for a long time and are excellent in safety for the human body.

(Prior Art) In many cases, the value of fish and shellfish is influenced by freshness. For this reason, various measures have been taken so that freshness is not reduced during transportation or storage. In general,
A method of quick freezing immediately after catching is employed, but in this case, a large-scale apparatus is required, and some fish and shellfish are not suitable for freezing. In addition, with the freezing, the destruction of the tissue due to the growth of ice crystals becomes a problem.
Therefore, various methods for keeping freshness without freezing have been tried.

As one of the methods, there is a use of a freshness preserving agent. As the freshness preserving agent, a method using gallic acid or a salt thereof and ascorbic acid or a salt thereof as active ingredients has been proposed (Japanese Patent Application Laid-Open No. Sho 60/1985). -221032 publication).

On the other hand, it is known that a product containing an extract of tea leaves and an extract of a ginger plant has an antimicrobial action (Japanese Patent Application Laid-Open No. 61-34790), but it has a freshness-retaining ability. It is not known.

(Problems to be Solved by the Invention) However, the method using gallic acid, ascorbic acid or a salt thereof in the use of a freshness preserving agent also has problems such as not yet having a sufficient freshness preserving effect.

The present inventors have conducted intensive studies to solve such a problem of the freshness preserving agent. As a result, the extract extracted from tea leaves and the one containing an antioxidant have a deodorizing effect, Have an effect of maintaining the freshness of the sushi very well.

An object of the present invention is to provide a freshness preserving agent and a freshness preserving method capable of favorably maintaining freshness of fresh fish and shellfish.

(Means for Solving the Problems) The present invention relates to a freshness preserving agent for preserving freshness of fresh seafood by directly contacting the same with fresh seafood, comprising an extract from tea leaves and an antioxidant And a freshness maintaining agent for fresh seafood.

The present invention also relates to a method for preserving freshness of fresh seafood, wherein a freshness preserving agent containing an extract from tea leaves and an antioxidant is brought into direct contact with fresh seafood. And a method for maintaining freshness of fresh seafood.

In the present invention, an extract obtained by extracting a fresh leaf or a dried product of tea leaves mainly with an organic solvent such as alcohols such as methanol, ethanol and propanol, ketones such as acetone and methyl ethyl ketone, water, or a mixed solvent thereof is used. These extracts contain various compounds such as flavone compounds, amine compounds, unsaturated aldehyde compounds, and organic acids such as tannic acid.

On the other hand, as the antioxidant, tocophenol, L-ascorbic acid, gallic acid, and the like are particularly preferably used from the viewpoint of freshness retention ability and safety to the human body. These antioxidants can be used alone or in admixture of two or more. It is sufficient to add the antioxidant in an amount of 0.1 to 5 times the extract.

The extract and the antioxidant can exert a freshness maintaining effect by being brought into contact with fish and shellfish as it is or dissolved in a solvent such as water or ethanol. As a contact method, any method such as spraying or dipping may be used. In particular, since the present extract is soluble in water, it is preferable to use the extract as a 0.01 to 10% by weight aqueous solution. This is because if it is less than 0.01% by weight, the effect of maintaining freshness cannot be sufficiently exhibited, and if it exceeds 10% by weight, the effect is not remarkably improved, and it is not economical. For example, 1 to 30 fish and shellfish are added to the aqueous solution.
After being immersed for about a minute, they may be transported or stored, or may be immersed in the aqueous solution during the transportation or storage period. Further, the aqueous solution may be intermittently or continuously sprayed on the surface of the fish or shellfish during transportation or storage.

In addition, by freezing the aqueous solution and laying the ice around fish and shellfish, or by using it as glaze water in frozen storage, it is possible to increase the freshness retention ability in combination with the effect of low temperature, which is particularly preferable.

(Example) Next, an example of the present invention will be specifically described.

Production Example of Extract 250 g of dry powder of tea tree leaves and 600 ml of ethanol were charged into a Soxhlet extractor and heated under reflux for 20 hours. The raw material residue was filtered off from the extract, and the filtrate was concentrated under reduced pressure to dryness to obtain 78.0 g of a dark green extract.

Example 1 The above extract and antioxidant were each dissolved in a 50% aqueous ethanol solution with the composition shown in Table 1 below, and the horse mackerel immediately after capture was sprayed for about 1 minute using a commercially available hand spray. After holding at 2 ° C for 48 hours, appearance and K
The value was measured.

The K value is measured by Bulletin Japanese Societvy Science
of Fish, 24 , 749-750 (1959). The K value indicates denaturation of the protein of fish and shellfish, and a lower K value indicates better freshness.

 Table 1 shows the results.

Example 2 The above extract and antioxidant were each dissolved in a 50% aqueous ethanol solution according to the composition shown in Table 2 below. After storing for 48 hours, the appearance and K value were measured. Table 2 shows the results.

As is clear from these results, it can be seen that the combination of the extract and the antioxidant has excellent freshness retention ability.

(Effect of the Invention) According to the present invention, fresh fish and shellfish are transported by using an extract from tea leaves and an antioxidant in combination as a freshness preserving agent, as compared with a case where the antioxidant is used alone. After storage or storage, the freshness has been significantly improved. Specifically, the appearance of fresh seafood is improved, for example, the eyes are transparent, the gills are clear red, and the measurement lines do not change color.
It was also found that the K value was significantly reduced.

Claims (5)

(57) [Claims] 1. A freshness preserving agent for preserving the freshness of fresh seafood by direct contact with the fresh seafood, comprising an extract from tea leaves and an antioxidant. And a freshness maintaining agent for fresh seafood. 2. The freshness maintaining agent for fresh seafood according to claim 1, comprising an aqueous solution containing 0.01 to 10% by weight of said extract. 3. The freshness preserving agent for fresh fish and shellfish according to claim 1, comprising a frozen product of an aqueous solution containing 0.01 to 10% by weight of said extract. 4. The method according to claim 1, wherein the antioxidant is tocophenol, L-
The fresh seafood freshness preserving agent according to any one of claims 1 to 3, wherein the agent is selected from the group consisting of ascorbic acid and gallic acid. 5. A method for preserving freshness of fresh seafood, wherein a freshness preserving agent containing an extract from tea leaves and an antioxidant is brought into direct contact with fresh seafood. A method for maintaining freshness of fresh seafood.