JP2015177779A - Method of producing processed chestnut, and processed chestnut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processed chestnut containing a large amount of polyphenol.SOLUTION: A method of producing a processed chestnut includes boiling a raw chestnut, whose hard shell is removed but astringent skin remains, with boiling water for 30-40 minutes; vacuum packing and then quickly freezing the resulting chestnut; and keeping the resulting chestnut refrigerated.

Description

  The present invention relates to a method for producing processed chestnuts and processed chestnuts. More specifically, the present invention relates to a processed chestnut manufacturing method in which raw chestnuts with astringent skin from which demon skin has been removed are heat-treated and then rapidly frozen to manufacture, and processed chestnuts manufactured by the method.

  Traditionally, chestnuts are tasted all over the world due to their taste and variety of cooking methods, but the production areas and seasons are limited, and whether they are raw chestnuts and heat-treated chestnuts (including peeled chestnuts) Regardless, drying, fruit browning, insect bite, mold, etc., and a decrease in palatability cannot be avoided, and the range of use as food is narrowed.

  The biggest cause is that the chestnut demon skin (outer skin) is made of fiber with rougher texture than ginnan and walnuts, so it is easy to dry. It passes through and enters the inside, causing a component change and causing deterioration in taste, aroma, color tone, and the like.

  In addition, chestnut astringent skin contains a large amount of tannin, a polyphenolic body with strong antioxidant power, which helps to prevent changes in fruit composition while fresh chestnuts are fresh. (Tianjin sweet chestnuts) and peeled chestnuts lose the antioxidant power that astringent skin had, so the browning of the fruits progresses rapidly, and at the same time the taste and aroma are lost, compared with those prepared with fresh chestnuts do not become.

  In addition, the well-known bottling “Kuri no Kanro-ni” is an anti-oxidant and an anti-oxidant that does not cause the fruit to lose its shape after peeling off the large Tamba chestnut demon skin and astringent skin with a sharp knife. Although it is manufactured by adding a sugar solution and heating, such a product tends to lose its shape when taken out from a bottle and subjected to secondary processing.

  Also, because it is soaked in a thick sugar solution, the application of secondary processing is limited, and the `` peeled chestnut '' that is soaked in the sugar solution is easily deformed and has a high addition like a maroon rasse. It is not used in the production of value food.

  Patent Document 1 discloses a cooked chestnut that retains its original color and flavor by applying a protein such as gelatin or collagen to the surface of the peeled chestnut when the peeled chestnut is contained in a container and sealed and heat-sterilized. ing.

  JP 2006-211996 A

Patent Document 1 describes that gelatin or collagen is separately added to the surface of peeled chestnuts when sterilized by heating, but does not describe a processing method for leaving a large amount of collagen in the material.
Focusing on the above problems, the object of the present invention is that it can be stored for a long time without surface treatment with proteins, water-soluble polysaccharides, etc. It is to provide processed chestnuts that can be easily cooked by suppressing the deterioration of taste, fragrance and color tone, expanding the use of quality and year-round processed foods.

The purpose is to produce raw chestnuts with astringent skin from which the demon skin has been removed, boiled with boiling water for about 30 to 40 minutes, vacuum packaged, and then subjected to quick freezing and frozen storage, and the present method Is achieved by producing processed chestnuts containing greater than 0.03 g per 100 g or about 0.39 g polyphenols.
In addition, the present inventors boiled raw chestnuts with astringent skin from which demon skin has been removed, boiled with boiling water for about 30 to 40 minutes, vacuum packaged, quickly frozen and stored frozen, the chestnut's original taste, The fragrance and color tone are easily maintained, and the present invention has been completed by finding opportunities for use as a quality and anniversary processed food.

  As described above, the present invention manufactures processed chestnuts so that fresh chestnuts with astringent skin from which demon skin has been removed are boiled with boiling water for about 30 to 40 minutes, and then subjected to quick freezing treatment after being vacuum-packed and stored frozen. Thus, it becomes possible to provide processed chestnuts containing more than 0.03 g per 100 g or containing about 0.39 g of polyphenol.

  In more detail, as shown in the test analysis results (FIGS. 2 and 3), the polyphenol content is 0.39 g per 100 g in the case of chestnut with astringent skin and 0.03 g per 100 g in the case of peeled chestnut. As shown in the test results of Fig. 4, it is proved that the storage of chestnuts with astringent skins and peeled straws is excellent in taste, aroma and color, and is an effective method for long-term storage. Therefore, the present invention can be utilized year-round.

The figure which shows one Example of this invention and shows the manufacturing process of processed chestnut. The figure which shows the analysis test result book of a chestnut with a strawberry with astringent skin. The figure which shows the analysis test result book of a chestnut with a striped straw. The figure which shows a vacuum packaging and frozen chestnut taste sensory test result.

Hereinafter, specific manufacturing processes and evaluations of the present invention will be described with reference to the drawings.
FIG. 1 shows the manufacturing process, the left column shows a rough process, and the right column shows the work contents.

1. Is a raw material preparation process, which prepares raw chestnuts.
In this process, the raw chestnuts are prepared in (1), and the selection work (2) for size and insect bite is performed, and the selected raw chestnuts are subjected to (3) cleaning, sterilization and insecticidal treatment. is there.
This treatment is performed by diluting the raw chestnut 300-600 times and immersing it in a 6% sodium hypochlorite solution placed in a water tank for about 10 minutes.
Insecticides are not removed by drug stripping as soon as they are removed or stored in ice (stored at -2 ° C for 4 weeks). Other methods include hot water treatment (soaked in hot water at 50 ° C. for 30 minutes) and fumigation treatment with methyl iodide.

  2. In the peeling process of (4), the demon skinning work of (4) is performed, and a knife is usually used, but it can also be carried out by a method of manual peeling and mechanical peeling. In either case, correct by visual inspection and machine, select (5), and inspect the quality.

  3. Is a boil process, and the work, removal, and sterilization are performed with a broom of (6). In this operation, the cooking time is slightly different depending on the variety and size, but it is possible to perform the squeezing and sterilization at the same time by boiling for about 30 to 40 minutes. Remove spills or remove with a spoon.

  4). In the inspection process of (7), the processed chestnut that has been boiled is immediately subjected to inspection and weighing in (7) with the coarse heat removed, and packaged in (8). Usually, it is packaged by vacuum pack packaging or air inert gas sealed pack, but it is not necessary to seal the gas when storing frozen.

  Next, 5. In this rapid cooling process, the packaged chestnuts are quickly subjected to quick freezing treatment (9) in an atmosphere of −30 ° C. ± 5 ° C. The quick freezing time varies by about 30 to 90 minutes depending on the processing amount and the freezing temperature.

6). Is a storage process, specifically storage and management in a freezer compartment.
This completes a series of manufacturing processes and enables long-term storage management.

  Next, the content of the frozen chestnut with astringent skin produced by the process of the present invention and the content of chestnut polyphenols in the conventional peeled cocoon, and the sensory test results of the old and new packaging and frozen chestnut produced by the process of the present invention will be described.

FIG. 2 is an analysis test report of chestnuts with astringent skin produced in the process of the present invention, and is a result of a test analysis by the Japan Food Analysis Center (Motoyoyogi, Shibuya-ku, Tokyo) (No. 13106672001-01).
The test method is the FOLIN-CIOCALTEU (foreign thiocult) method. The foreign thiocult method is a method that utilizes the color of a foreign reagent (phenol reagent) reduced by a phenolic hydroxyl group, and has been adopted as an official ISO method for analyzing the total amount of polyphenols in tea leaves and tea beverages. Yes.
As a result of analysis by this method, it was found that the amount of polyphenol was 0.39 g / 100 g.

FIG. 3 is a conventional striped chestnut analysis test report and results at the Japan Food Analysis Center (No. 13106672002-01).
The test method is the FOLIN-CIOCALTEU (forein thiocult) method as in FIG.
According to this analysis result, the amount of polyphenol was 0.03 g / 100 g.

  In this way, it was found that the content of chestnut polyphenol in the straw with astringent skin manufactured according to the present invention in FIG. 2 is 13 times the conventional value in FIG.

It is said that the higher the content of polyphenol, the better the body, but no processed chestnut exceeding the conventional content has been proposed.
The present invention has been a trial and error for a novel processing step, and has resulted in a processed chestnut having a polyphenol content exceeding the conventional content.
Furthermore, it was also confirmed that the chestnut with the astringent peel according to the present invention has less deterioration of the components than the conventional peeled chestnut and can maintain the quality in the long term.

FIG. 4 is a taste sensory test analysis result of the vacuum packaged / frozen chestnut of the present invention.
That is, it is the result of normal freezing and quick freezing treatment of chestnuts with the rinds with astringent skin of the present invention and chestnuts with conventional peeled straws, and investigation after 57 days.
The comparison items are four items of the color, flesh quality (hardness), taste and fragrance of the flesh, but it was found that the chestnuts were peeled off with the astringent skin and the results were better than the chestnuts, and the deterioration of the ingredients was also suppressed.

The test survey was conducted at the Agricultural Processing Instruction Center in Ibaraki Agricultural Research Center.
The sensory test was conducted by a predetermined evaluation method with the participation of a total of 12 monitors from the Ibaraki Horticultural Research Institute, Ibaraki Agricultural Processing Instruction Center, Kasama Regional Agricultural Improvement Promotion Center, and Kasama City Agricultural Administration Division.

  Next, a method for cooking or processing the frozen chestnut with astringent skin manufactured in the process of the present invention will be described.

In the first cooking method, 500 g of the processed chestnut produced in the present invention is put in edible oil (about 1 liter) previously heated to 180 ° C. to 200 ° C. while being frozen and fried for about 3 minutes.
When the astringent skin becomes fox-colored, take it out of the pan and sprinkle with salt.
It can be eaten as a salty fried chestnut confectionery as well as with cinnamon. Furthermore, it can be eaten as a chestnut confectionery by vacuum packaging.

Next, 500 g of the processed chestnut produced in the same manner is placed in a pan filled with about 1 liter of water while being frozen and boiled. Add about 30% (150 g) of white sugar to the chestnut and simmer for about 10 minutes while removing the acupuncture at medium heat. Discard the broth afterwards.
Add 1 liter of water and 350 g of sugar to the boiled chestnuts and simmer for 30 minutes on low heat.
Drain the boiled chestnuts in a separate container so that no juice enters. Dispose of the broth because it is astringent.
Boiled chestnuts in sugar water (sugar solution) with the same amount of water and sugar are added, and then the juice is boiled. It can be stored in a vacuum pack and can be boiled at any time by freezing.
In addition to this, it can be used for various side dishes and sweets such as tempura, chestnut rice, boiled honey, yokan and paste.

  By using the processed chestnuts processed according to the present invention as described above, quality such as taste, aroma, color tone, shelf life, etc. is maintained for a long time compared to conventional raw chestnuts and processed chestnuts, and it can be used all year round. It is possible to provide safe and reliable processed chestnuts, such as prevention of mold and bacteria by freezing and storage.

  In particular, since it is possible to suppress a decrease in the content of polyphenols, it has been confirmed that even chestnuts stored frozen for two years have almost no deterioration in shape and components.

Claims (3)

  A method for producing processed chestnuts, in which raw chestnuts with astringent skin from which the demon skin has been removed are boiled with boiling water for about 30 to 40 minutes, then packed in a vacuum pack, and then rapidly frozen and stored frozen.   Processed chestnuts produced by the method of claim 1 and containing more than 0.03 g polyphenol per 100 g.   A chestnut manufactured by the method of claim 1, wherein the processed chestnut contains about 0.39 g of polyphenol per 100 g.

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