JP2003339338A - Method for processing fruit and vegetable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method with which astringency of a fruit or vegetable having an astringent component is simply removed in a short period of time and a method with which an unfreezable fruit or vegetable is produced by a process approximately the same as that of the method. <P>SOLUTION: The method for removal of astringency of the fruit and the vegetable comprises immersing the fruit or vegetable in alkali ion water, taking out the fruit or vegetable from the alkali ion water and freezing and after passage of a fixed time, thawing and drying the fruit or vegetable. The fruit or vegetable is further frozen to give the excellent unfreezable fruit and vegetable. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for easily removing astringency of a fruit or vegetable having an astringency component in a short period of time,
It also relates to a method of processing fruits or vegetables into an antifreeze regardless of whether or not it has an astringent component.

[0002]

2. Description of the Related Art "Persimmon persimmon", which does not lose its astringency even if the fruit is red and ripe, cannot be used as it is. Therefore, various types of de-astringent treatment have been conventionally applied to astringent persimmons.

[0003]

The most primitive method of removing astringency is to dry persimmons, that is, to process the persimmons into "dried persimmons". When making dried persimmons, it is common practice to peel the ripe astringent persimmon, dry it in the sun, and dry it under natural conditions, but this method requires that the sun be dried for about one month, which is extremely Takes time.
Moreover, there is a problem that the quality depends on the weather conditions. For example, if the temperature is too high, blue mold may adhere to the surface of the persimmon.

On the other hand, in recent years, deastringent methods using alcohol have been widely practiced. When this method (alcohol is sprayed on the surface of the astringent persimmon or the astringent persimmon is immersed in an alcohol solution), deastringency can be completed within a few days, and the problem of blue mold can be preferably avoided. .

However, since persimmons that have been deastringent using alcohol become soft as a whole, there is the problem that it is difficult to cut them with a kitchen knife, and the original taste and texture of raw persimmons are impaired. Will be lost. Also, persimmons that have been deastringent using alcohol will have their internal water frozen strongly when frozen for storage. Therefore, in this state, a knife such as a knife cannot be inserted, and unless it is thawed, it cannot be used for food. However, when such a frozen persimmon is thawed, there is a problem that the frozen water is separated and becomes softer than the state before the freezing.

The present invention has been made to solve the above-mentioned problems of the prior art, and it is possible to easily remove astringent fruits or vegetables having an astringent component in a short period of time. It is an object of the present invention to provide a method capable of producing an antifreeze fruit or vegetable by a process substantially similar to the method.

[0007]

The method for processing fruits and vegetables according to the present invention comprises immersing fruits or vegetables in alkaline ionized water, then removing from the alkaline ionized water and freezing, and thawing after a predetermined time has elapsed. -Characterized by performing a drying process. By performing this processing, for fruits and vegetables (for example, astringent persimmon) that have an astringent component,
You can easily get rid of astringency in a short time. Moreover, because the pulp and the like can be removed from the astringent state, it can be easily cut, the original taste and texture are not impaired, and the time required for the astringent treatment is greatly reduced compared to the conventional method. It can be shortened.

[0008] Further, since the free water inside is removed by performing the thawing / drying process, there is no possibility of "strong freezing" when frozen again after the thawing / drying process. For example, even if it is frozen in the temperature range around -24 ° C, it can be easily cut with a knife, etc., and can be easily torn off with teeth (antifreeze). ) Can be processed.

Further, before freezing, a step of immersing the fruit or vegetable in the polymerized chitosan solution may be carried out, and in this case, better antifreezing property can be obtained. Further, before or after this step, or instead of this step, a step of immersing in a potassium carbonate solution or a calcium lactate solution may be carried out, and in this case, the deastringency treatment may be more preferably performed. it can.

Further, when the thawing / drying treatment is carried out for 3 days or more, the evaporation and drying of water considerably progress. Therefore, for example, when the processing method according to the present invention is applied to astringent persimmon, a dried persimmon-like processed persimmon. Therefore, compared with the conventional method for producing dried persimmon, the time can be greatly shortened.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments (first and second embodiments) of the present invention will be described below.

(First Embodiment: Removal of Astringent Persimmon) First, a fresh astringent persimmon is prepared and peeled. Next, the peeled astringent persimmon is immersed in alkaline ionized water having a pH of 7.5 or higher for at least 1 minute or longer (preferably 5 to 10 minutes). After that, drain water well and put in a freezer (freezer) to freeze. At this time, the temperature in the freezer is -18 ° C.
The following is preferable.

Freezing is carried out for 1 to 3 days (preferably about 24 hours). After that, the persimmons are taken out from the storage and thawed and dried for 1 to 7 days (preferably about 24 hours). When the frozen persimmon is thawed, the water frozen during freezing will be melted and released from the pulp appropriately. Then, by drying this, excess water (free water) is removed from the inside of the persimmon, and astringent components (tannin) are also removed.

The thawing / drying treatment is basically carried out by leaving the frozen persimmon at room temperature (that is, natural thawing and natural drying). At that time, a fan or the like is used to blow air, or Alternatively, it may be forcibly dried in an atmosphere of low humidity.

The persimmon obtained through such a process has no astringency and becomes "sweet persimmon", which is edible (raw).
Besides, it can be suitably used as a raw material of processed foods (persimmon confectionery, persimmon beverages, etc.).

In particular, by performing the step of immersing in alkaline ionized water, it is possible to perform deastringency more suitably than when simply chilling and thawing, and also to remove astringency while the pulp is in a somewhat hard state. It can be carried out. To explain this point in more detail, since the alkali ion water has small water molecule clusters, it has good permeability, and therefore, when raw fruits and vegetables are immersed in alkali ion water, The alkaline ionized water will penetrate smoothly into it.

The alkaline ionized water has a function of neutralizing the tannin, which is an astringent ingredient, to some extent and also has a high thermal conductivity because the water molecules are in a polymerized state. When a fruit or the like in which alkaline ionized water has penetrated into the tissue is frozen, growth of ice crystals is hindered, and formation of large ice crystals in the tissue can be suitably suppressed.

When raw fruits and the like are frozen, the water in the tissues freezes, but when they are simply frozen without being immersed in alkaline ionized water, ice crystals usually grow large. , It will freeze strongly. As a result, the cell membrane will be destroyed, and when thawed, this will melt and a large amount of water will flow out of the tissue,
It will be in the so-called "guzzling" state.

Further, even when the conventional astringent method using alcohol is used, the pulp becomes so soft that it is difficult to cut with a kitchen knife or the like, but when the fruit etc. soaked in alkaline ionized water is frozen, As described above, strong freezing of water in the tissue, and tissue destruction due to freezing are preferably avoided, so even if water leaks during thawing, it will be appropriately suppressed, and the pulp etc. It can be thawed in a somewhat rigid state (state in which the properties do not change much from the raw state). Therefore, in addition to being easy to cut, the original taste and texture of raw persimmon are not impaired, and the time required for deastringency treatment can be greatly shortened as compared with the conventional method.

Further, even if it is refrigerated again from this state, since free water has already been removed, there is no possibility of "freezing" (antifreeze). For example, -24 ° C.
Even if it is frozen in the front and back temperature zones, you can easily cut it as it is with a knife etc., and you can easily bite it with your teeth, so you can eat it directly as an ice confection without thawing It is also possible to do so. Further, even if it is thawed, its properties do not change so much, so that it can be repeatedly cooled and thawed, and it can be stored for a long time while maintaining its quality.

In this embodiment, the target of processing is "astringent persimmon", but it can also be applied to other fruits and vegetables having an astringent component. Further, it can be applied to other fruits and vegetables (for example, figs, grapes, etc.) having no astringent component as a method for producing antifreeze fruits and vegetables.

(Second embodiment: deastringency of astringent persimmon / production of dried persimmon-like persimmon) First, astringent persimmon in a raw state is prepared and peeled. Next, the peeled astringent persimmon is immersed in alkaline ionized water having a pH of 7.5 or higher for at least 1 minute or longer (preferably 5 to 10 minutes). After that, drain water well and put in a freezer (freezer) to freeze. At this time, the temperature in the freezer is preferably -18 ° C or lower.

Freezing is for 1 to 3 days (preferably 2 days)
To do. After that, the persimmons are taken out of the refrigerator and thawed and dried for 1 to 7 days (preferably 3 days). When the frozen persimmon is thawed, as described above, the water frozen during freezing is melted, and it will be appropriately released from the pulp.By drying this free water, excess water is removed from the inside of the persimmon, The astringency component (tannin) will also be removed.

The thawing and drying treatment is carried out by placing the frozen persimmon at room temperature and blowing it with a fan or by forcibly drying it in an atmosphere of low humidity. However, since the surface drying occurs in the second day after the start of the thawing / drying treatment, it is preferable to carry out this treatment in a room where the temperature is controlled.

The persimmon obtained through such a process becomes "sweet persimmon" because the astringency is eliminated. In addition, the surface of persimmon becomes dry and wrinkled and becomes "dried persimmon", which can be used as it is as "dried persimmon-like processed persimmon", or as a raw material for processed foods (persimmon sweets, persimmon drinks, etc.). Can be used as

In particular, as described above, by carrying out the step of immersing in alkaline ionized water, deastringency can be suitably carried out without destroying cells and tissues.

Further, conventionally, it took about 1 month to produce dried persimmons, but according to the method according to the present embodiment, processed persimmons (dried persimmon-like processed persimmons) having the same properties as dried persimmons are manufactured in about 1 week. Therefore, the time required for processing can be greatly reduced.

Further, even if it is frozen again from this state, the free water has already been removed, so there is no possibility of "freezing" (antifreeze), and like the first embodiment, Even if it is frozen in the temperature range around -24 ° C, it can be easily cut with a knife or the like as it is, and can be easily torn off by teeth. Therefore, it is possible to eat directly as an ice confectionery without thawing. Further, even if it is thawed, its properties do not change so much, so that it can be repeatedly cooled and thawed, and it can be stored for a long time while maintaining its quality.

As described above, in both the first and second embodiments, the peeled persimmon is immersed in alkaline ionized water, then drained and frozen. Before freezing here, persimmons may be dipped in a polymerized chitosan solution (8-fold solution), and then frozen after waiting for the chitosan solution to dry. In this way, when frozen again after the thawing / drying process, it is possible to obtain a better frozen anti-persimmon. That is, it is possible to provide a state in which it can be more easily cut, and a state in which it can be more easily bitten by the teeth.

Instead of immersing the persimmon in the chitosan solution, or before or after the step of immersing the persimmon in the chitosan solution, the step of immersing the persimmon in the potassium carbonate solution or the calcium lactate solution can be carried out. In this case, the astringency component (tannin) contained in the astringent persimmon becomes insoluble by binding with potassium carbonate or calcium lactate in the solution, and the astringency component is not perceived by human taste. It can be processed persimmon.

The potassium carbonate solution used here is
Potassium carbonate can be extracted and produced from ash obtained by burning persimmon trees, branches, leaves and the like. Alternatively, industrially produced potassium carbonate or calcium lactate may be used.

[0032]

As described above, according to the fruit and vegetable processing method of the present invention, fruits and vegetables having good antifreezing properties can be produced by a simple operation and in a short time. can do.

When applied to fruits or vegetables having an astringent component, deastringency can be easily achieved in a shorter time than in the conventional method. Moreover, since it is possible to de-astringent while the flesh etc. are hard, it can be easily cut, the original taste and texture of the ingredients are not impaired, and the time required for de-astringent processing is also compared to the conventional method. And can be greatly shortened.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4B016 LC02 LC06 LE03 LG01 LG05                       LK01 LK05 LK09 LP08 LP11                       LP13                 4B069 BA03 CA06 CA08 HA01 HA11                       HA12 KA06 KA10 KB03 KC11                       KC13 KC24 KC29

Claims (5)

[Claims] 1. Processing of fruits and vegetables, characterized in that the fruits or vegetables are immersed in alkaline ionized water, then taken out from the alkaline ionized water, frozen, and thawed and dried after a predetermined time has elapsed. Method. 2. The method for processing fruits and vegetables according to claim 1, wherein the fruits or vegetables are frozen again after the thawing / drying treatment. 3. The method for processing fruits and vegetables according to claim 1, wherein a step of immersing the fruits or vegetables in a polymerized chitosan solution is carried out before freezing. 4. The fruit according to claim 1, wherein a step of immersing the fruit or vegetable in a potassium carbonate solution or a calcium lactate solution is performed before freezing. How to process vegetables. 5. The method for processing fruits and vegetables according to claim 1, wherein the thawing / drying treatment is performed for 3 days or more.