JP5429874B2 - Frozen astringent skin peeling method for Japanese astringent Japanese varieties - Google Patents

Description

  The present invention relates to an astringent skin peeling method of, for example, a good astringent skinned Japanese corn variety.

  Japanese chestnuts have poor astringent skin peelability compared with Chugokuguri, and consumption at home is sluggish. In addition, Japanese chestnuts are problematic because of the time and cost required to peel off the astringent skin during processing. For this reason, a number of methods for peeling off Japanese acorns have been studied.

  At present, as a method for removing the Japanese astringent skin, a method of scraping the entire surface of the pulp with a knife is mainly used. However, this method has a problem in that the cost such as the labor cost is high and the yield of the pulp is considerably low as 50 to 60%.

In addition, the following methods are known as the method for peeling off Japanese acorns.
Patent Document 1 discloses an astringent peel exfoliating and shaping method including immersing a chestnut with astringent peel from which a demon skin has been peeled off in an aqueous sodium hydroxide solution.

  Patent Documents 2 and 3 disclose methods utilizing the adiabatic expansion force of water vapor. Specifically, in Patent Document 2, chestnuts are put in an airtight container, heated under pressure with a gas such as water vapor, and then instantaneously released to a buffer device under normal pressure to peel off the demon skin and astringent skin. A method for peeling chestnuts is disclosed. In Patent Document 3, chestnuts are put in an airtight container, pressurized and heated with a gas such as water vapor, and then instantaneously discharged to a buffer device under normal pressure. After the demon skin is separated and removed, high-speed water vapor is sprayed. A chestnut skinning method characterized by separating and removing astringent skin from the chestnut surface is disclosed.

  In Patent Document 4, fresh chestnuts with astringent skin are immersed in warm water of 50 ° C to 80 ° C or showered with warm water, and the surface temperature of the astringent skin is raised to 50 ° C to 80 ° C. A method for peeling a fresh chestnut astringent skin, characterized by spraying a jet of high-pressure water and peeling the astringent skin.

  Patent Document 5 discloses a chestnut skin releasing method characterized in that the chestnut is subjected to fluid heating in which heat treatment is performed while flowing hot air.

  Patent Document 6 discloses chestnut skinning characterized by performing treatment with a chemical solution (hydrochloric acid solution, etc.) on chestnuts with demon skins or chestnuts completely or incompletely removed, followed by microwave irradiation treatment. A processing method is disclosed.

  Patent Document 7 discloses a chestnut skinning method characterized by including an incision step of making an incision in a chestnut seat, and a step of immersing the chestnut in which the incision is formed in an aqueous solution containing an enzyme agent. ing.

  However, these conventional methods are all large-scale and require special equipment and machines, or require a long chemical treatment and heating time, and are not practical methods. Moreover, chemical treatments such as acids and alkalis have the disadvantage that the fruit is discolored. Furthermore, these conventional methods have the disadvantages that it is difficult to completely peel the Japanese astringent skin, and the flesh surface layer adheres to the side of the astringent skin.

  Patent Document 8 discloses a chestnut astringent skinning method characterized by scratching astringent skin with a knife or the like and then subjecting the astringent skin to microwave irradiation treatment with a microwave irradiation device or the like, or subjecting it to heat treatment with an oven or the like. Has been. However, in this method, there is a problem that the quality of the fruit changes, for example, the fruit surface becomes hard when the heat treatment is performed.

  Patent Document 9 discloses a method of freezing and thawing chestnuts before ripeness and peeling off the demon skin and astringent skin at the same time. However, in this method, it is necessary to collect the ripening chestnuts before they fall from the tree and to freeze them after taking out the fruits from the squids.

JP 54-80450 A JP 54-119077 JP-A-57-12988 Japanese Patent Laid-Open No. 2001-238654 JP 2000-125832 A Japanese Patent Laid-Open No. 4-112779 Japanese Patent Laid-Open No. 10-84928 JP 2008-54548 A JP 2002-238526 A

  In view of the above-mentioned circumstances, the present invention provides a method that can peel the fruit astringent skin of a good astringent skinned Japanese corn variety easily and in a short time without changing the quality of the fruit. With the goal.

  As a result of diligent research to solve the above problems, the ripe fruit of the free astringent peeled Japanese corn cultivar after freezing was scratched, or the ripe fruit that had been scratched was subjected to freezing, so that the demon skin and astringent skin The present invention has been completed.

The present invention includes the following.
(1) A method for peeling a chestnut astringent skin, in which ripe fruits of a good astringent skinned Japanese corn variety after freezing are scratched and the demon skin and astringent skin are peeled simultaneously.
(2) A chestnut astringent skinning method, comprising subjecting a ripe fruit of a good astringent skinned Japanese corn variety with scratches to freezing treatment and then peeling the demon skin and astringent skin simultaneously.
(3) The method according to (1) or (2), characterized in that the good astringent peeled Japanese varieties are Japanese corn varieties Porotan (variety registration No. 15658) or their cultivars.
(4) The method according to any one of (1) to (3), wherein the wound site is on a line that goes around the center of the seat from the top of the fruit.

  According to the present invention, fruit astringent skin of a good astringent skin peeled Japanese corn variety can be peeled easily and in a short time without changing the quality of the fruit, and the cost reduction of the astringent skin peeling in the chestnut processing field is achieved. Can do.

It is a system diagram of Polotan. It is a figure which shows the wounding site | part of a fruit. It is the photograph of the fruit after freezing. It is a photograph of the fruit after peeling of the demon skin and the astringent skin in Example 1. It is the photograph of the fruit (a) before freezing after the wound in Example 2, and the fruit (b) after freezing. Fruit (b) peeled with devil skin and astringent skin in Example 2 (a) and fruit (b) of cultivar “Tsukuba” with skinned devil skin and astringent skin in the same manner as described in Example 2 It is a photograph.

Hereinafter, the present invention will be described in detail.
The chestnut astringent skin peeling method according to the present invention is a method in which a ripe fruit of a good astringent skinned Japanese corn cultivar after freezing is scratched and the demon skin and the astringent skin are simultaneously peeled (hereinafter referred to as “first method”). Further, the chestnut astringent skin peeling method according to the present invention is a method in which a ripe fruit of a good astringent skin peeled Japanese corn variety is subjected to freezing, and then the demon skin and the astringent skin are simultaneously peeled (hereinafter referred to as `` secondary '' Method "). Hereinafter, the first method and the second method may be collectively referred to as “the present method”.

  In this method, by freezing the ripe fruit of the good astringent skin peeled Japanese corn varieties, the astringent skin adheres to the demon skin instead of the flesh, so peeling off the devil skin and the astringent skin at the same time peels off the skin. Can be peeled off.

  Here, the good astringent skin peeled Japanese corn varieties mean varieties excellent in astringent skin peelability among Japanese varieties. Examples of the good astringent peeled Japanese corn varieties include Japanese corn cultivar “Porotan” and its progeny cultivars “550-40” or their cultivars. "Porotan" was registered as a cultivar as registration number 15658 on October 22, 2007 by the seedling method. Its characteristics are as follows. (1) Astringent skin peelability is good, (2) Large fruit, (3) Powdery and excellent in taste, (4) Early growth, (5) Less fruit, (6) Insect damage rate depending on location high. FIG. 1 shows a system diagram of “Porotan”. As shown in FIG. 1, “Porotan” is a hybrid variety of “550-40”, which is an early-growing large fruit line, and “Tanzawa”, which is an early-growing main variety. “Porotan” is provided by the Fruit Tree Research Institute of the National Agriculture and Food Research Organization.

  In addition, examples of the “Porotan” lineage varieties include, for example, hybrid varieties of the varieties shown in FIG. 1 and “Porotan”.

  Further, the term “ripe fruit” as used herein means a fruit that is harvested in a state where the straw is cleaved. In general, the ripe fruit demon skin and zodiac are colored brown.

  In the first method, first, a ripe fruit of a good astringent skin peeled Japanese corn variety is subjected to a freezing treatment. For example, the ripe fruit is placed in a plastic bag and stored in a freezer at −80 to −10 ° C. (preferably −30 to −20 ° C.) for 1 day to 48 weeks (preferably 1 to 2 weeks). After storage, the frozen ripe fruit is thawed to an extent that can be damaged (for example, 30 minutes to 1 hour) at room temperature (for example, 15 to 25 ° C.). After thawing, the ripe fruit is scratched and peeled to peel off the demon skin and astringent skin simultaneously. For example, as shown in FIG. 2, the wound site is the longest line on the line that goes around the center of the seat from the top of the fruit, as shown in FIG. Make scratches (cuts) to the point where

  On the other hand, in the second method, the ripe fruit of the good astringent peeled Japanese corn variety is first damaged. After scratching, the scratched ripe fruit is subjected to a freezing treatment. After freezing, after thawing, peel off the demon skin and astringent skin at the same time. The method of scratching, freezing treatment conditions, and thawing conditions can be in accordance with the first method described above.

  According to the present method described above, the fruit astringent skin of a good astringent skinned Japanese corn variety can be peeled completely and in a short time without using a special machine, and labor and cost can be greatly reduced.

  After applying this method, the astringent skin can be easily peeled with bare hands. Further, since only the astringent skin can be removed, the surface of the pulp after peeling is very beautiful, and the yield of the pulp is high.

  Furthermore, according to this method, a fruit (or pulp) can be provided without changing the quality of the fruit.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, the technical scope of this invention is not limited to these Examples.

[Example 1] Simultaneous peeling of demon skin and astringent skin by scratching ripe fruits after freezing Ripe fruits harvested in a timely manner from "Porotan" planted at the Fruit Tree Laboratory .

  The fruit was placed in a plastic bag and stored in a freezer (Teon) at -20 ° C for 1 week. FIG. 3 is a photograph showing the appearance of the fruit after freezing.

  After storage for one week, the fruit taken out from the freezer was melted at room temperature for about 30 minutes, and then the demon skin was scratched to reach the flesh (approximately 3 mm). The wound site was the longest line on the line that passed from the top of the fruit to the center of the seat and circled (FIG. 2). Peeling was performed by manually peeling the demon skin and the astringent skin simultaneously without using tools.

[Example 2] Ripe fruit harvested at the right time from "Porotan" planted at the Fruit Tree Research Institute I tried.

  Before freezing, the devil skin of the fruit was scratched to the extent that it reached the flesh (approximately 3 mm). The wound site was defined as the longest line on the circle that passed through the center of the seat from the top of the fruit. After wounding, the fruit was placed in a plastic bag and stored in a freezer (TAEON) at -20 ° C for 1 week.

  After storage for one week, the fruit was melted at room temperature for about 30 minutes, and the demon skin and the astringent skin were peeled off as if they were manually peeled off at the same time.

The peeling results of the demon skin and astringent skin in Examples 1 and 2 are shown in FIGS.
FIG. 4 is a photograph of the fruit after peeling the demon skin and astringent skin in Example 1. In Example 1, when frozen, the demon skin became hard, so the fruit could not be damaged until it melted to some extent. In the fruit of "Porotan", the astringent skin adsorbed toward the demon skin, so that the astringent skin could be removed at the same time as the demon skin was removed.

  On the other hand, when the fruits of the “Tsukuba” and “Tanzawa” strains are subjected to the peeling method described in Example 1, the astringent skin is also adsorbed to the pulp, so that the astringent skin can be removed from the fruits. There wasn't.

FIG. 5 is a photograph of the fruit (a) before freezing and the fruit (b) after freezing after wounding in Example 2.
In Example 2, when the wounded fruit was frozen, the slightly scratched part opened and the flesh became visible (FIG. 5 (b)). In Example 2, after melting for about 30 minutes and peeling off the devil skin and the astringent skin from the wounded portion of the “Porotan” fruit, the astringent skin could be removed cleanly.

  FIG. 6 shows the fruit (Porotan) peeled with demon skin and astringent skin in Example 2 (a) and the cultivar “Tsukuba” which peeled devil skin and astringent skin in the same manner as the skinning method described in Example 2. It is a photograph of fruit (b). In addition, Table 1 below shows the average astringent skin peeling rate in the fruits of various varieties obtained by peeling off the demon skin and the astringent skin by the peeling method described in Example 2. The average peel peel rate was calculated by taking the average of 10 fruits by calculating the ratio of the area where the peels per fruit were peeled off without adhering to the flesh.

  As can be seen from FIG. 6 and Table 1, in the varieties such as “Tsukuba”, “Rihei”, “Tanzawa”, “Kunimi”, etc. I couldn't remove the astringent skin cleanly.

Claims (3)

A chestnut astringent skinning method characterized by scratching demon skin and astringent skin at the same time by scratching a frozen Japanese cultivar Porotan (variety registration No. 15658) or a ripe fruit of the strain . A method for peeling a chestnut skin, which comprises subjecting a damaged Japanese cultivar Porotan (variety registration No. 15658) or a ripe fruit of its strain to freezing treatment and then peeling the devil skin and the astringent skin simultaneously. . The method according to claim 1 or 2 , wherein the wound site is on a line that goes around the center of the seat from the top of the fruit.

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