JP6033630B2 - Processed food for astringency and method for producing the same - Google Patents

Description

  The present invention relates to a novel processed food such as dried fruit using astringent fruit and a method for producing the same.

  In general, persimmon can be broadly divided into candy and astringent. Since sweet potato has less astringency, it can be eaten as it is, but astringent has a strong astringency and cannot be eaten as it is.

  The cause of the astringency is soluble (water-soluble) tannin contained in the astringency. Soluble tannins are denatured when condensed to insoluble tannins that do not feel astringent.

  Therefore, when using astringents for food, generally, “astringency removal” (de-astringency treatment) is performed in which soluble tannin contained in the astringents is condensed using carbon dioxide gas or alcohol.

  However, since insoluble tannin returns to soluble tannin when heated (astringent return), even if it is an astringent from which astringency has been removed, astringency occurs again and the flavor is impaired when heated by processing or the like. Therefore, when processing astringency, there is a disadvantage that it cannot be easily heated.

  Dried persimmon is widely known as a processed food using astringency.

  Dried persimmons are made by, for example, drying the sun by hanging harvested astringents around the eaves and reducing the water content. By drying, soluble tannin is denatured into insoluble tannin, so that it does not feel astringent. As a result, the original sweetness of astringents becomes prominent, and dried persimmons with a unique flavor can be obtained.

  In Japan, the harvest time of straw is limited to a certain period around October. Dried persimmons cannot be stored for a long time unless they are frozen and stored because there is a risk that microorganisms such as mold will grow and change in quality. For this reason, dried persimmons have a strong feeling as seasonal foods with limited time for distribution.

  As prior arts related to the present invention, there are, for example, Patent Documents 1 and 2.

  Patent Document 1 discloses a method for removing astringency that can be performed in a short time. Specifically, astringency is set in an airtight tank, and microwaves are irradiated to the astringency while decompressing. The astringency is maintained at about 40 ° C. by decompression. Then, carbon dioxide gas or alcohol gas is sprayed in the tank, and these gases are permeated into astringency.

  Patent Document 2 discloses a processing method for astringency that can adjust the production time of dried straw. Specifically, the peeled astringents are stored frozen, appropriately thawed and dried to adjust the production time of the dried persimmons.

JP 61-128837 A JP 2000-217536 A

  As described above, astringents have a limited harvest time and are difficult to handle as processed food materials. Therefore, there are not many types of processed foods using astringency.

  Accordingly, an object of the present invention is to provide a new processed food for astringency that can be stored at room temperature for a long period of time.

  The present invention is a method for producing processed foods using astringency, and includes the following six steps.

  In the first step, the raw astringency is removed and the soluble tannin contained in the astringency is insolubilized. In the second step, the astringent that has been subjected to the astringent treatment is frozen. In the third step, the frozen astringency is cut out. In the fourth step, the cut astringent is primarily immersed in the sugar solution under refrigeration. In the fifth step, the astringent soaked in the primary soaking is secondary soaked in the sugar solution while reducing the pressure at 38 ° C. or lower. In the sixth step, the astringent soaked in the second stage is dried at 38 ° C. or lower.

  According to this manufacturing method, the temperature is maintained at 38 ° C. or lower after the de-astringency treatment. If it is 38 degrees C or less, there is no possibility that astringency may arise by astringent return. Therefore, it is possible to obtain a processed food that can be tasted with a unique flavor without feeling astringency.

  Astringents are frozen in the middle of processing, allowing long-term storage while maintaining quality. Therefore, the production time can be adjusted, and planned production throughout the year can be realized.

  By soaking astringency in a sugar solution, flavor and the like can be improved, and preservation at room temperature can be ensured. Furthermore, by dividing the immersion of the sugar solution into two stages, the sugar solution having a high sugar content can be efficiently permeated into astringency even at a low temperature.

  For example, calcium lactate may be added to the sugar solution used in the fourth step.

  If it does so, excessive softening of an astringency can be prevented and deformation | transformation can be suppressed.

  For example, in the fourth step, the astringent may be immersed in a sugar solution maintained in a temperature range of 0 ° C. to 10 ° C. for 10 hours to 24 hours.

  If you slowly thaw the astringent, the astringent tissue will be destroyed and softened. As a result, the sugar solution can easily permeate the astringency, and even if the sugar solution has low fluidity due to low temperature, the sugar solution can be spread throughout the astringency by simply immersing it for 10 to 24 hours.

  It is preferable to use a sugar solution having a higher sugar content than the sugar solution of the fourth step as the sugar solution of the fifth step.

Then, the sugar solution having a high sugar content can be uniformly permeated into the entire astringency in a short time.
It is preferable that the water activity of the processed food of astringency produced using the production method described above is 0.7 or less.

  Then, long-term storage at room temperature is possible, and convenience is improved.

  According to the present invention, it is possible to obtain a novel processed food for astringency that can be manufactured throughout the year.

It is a flowchart showing the manufacturing process in this embodiment. It is a picture of a candy cake. It is a table | surface showing the sensory test result.

<Method of manufacturing candy>
FIG. 1 is a flowchart showing a manufacturing process of a novel processed food (dried fruit-like candy) according to the present invention. Hereinafter, this embodiment will be described in detail with reference to this flowchart. However, the following description is merely illustrative in nature and does not limit the present invention, its application, or its use.

(material)
Raw astringent fruit is used as the raw material. If it is a raw astringent, the kind and production place are not ask | required. In addition, the size and maturity can be appropriately selected according to the required quality.

(First step)
In order to insolubilize the soluble tannin contained in the raw astringency, de-astringency processing is performed (step S1). The astringent treatment is used in the production of dried persimmons. For example, there are various methods for removing astringency such as carbon dioxide gas treatment, alcohol treatment, and hot water treatment. In this method, it is sufficient that the astringency can be reduced to a level at which it can be eaten deliciously, as with dried persimmons, and any de-astringency treatment method can be applied.

  In this step, astringency cut processing or the like is not performed, and the form at harvest (spherical fruit state) is maintained.

(Second step)
The astringent that has been subjected to the astringent processing is frozen (step S2). Specifically, the astringent fruit that has been subjected to the astringent treatment is placed in an environment of 0 ° C. or lower, preferably −20 ° C. or lower as it is, and frozen. Freezing allows long-term storage of astringency.

  Therefore, the processing up to this step is performed at the harvest time of the astringency, and a sufficient amount of astringency is stored frozen. By doing so, it is possible to adjust the production time and realize planned production throughout the year. Since it freezes in the form at the time of harvest, quality deterioration during cryopreservation can be suppressed, and even a large amount can be handled easily.

(Third step)
The frozen astringency is cut out (step S3). Specifically, the frozen astringency is cut into, for example, eight equal parts under a temperature environment where the frozen state can be maintained. Since the astringent is hardened by freezing, it can be easily cut into any size without destroying the tissue.

  Since the treatment is performed at a low temperature, quality deterioration due to microbial contamination can be prevented. For completeness, an alcohol dipping treatment may be added in which the cut astringent is dipped in alcohol for a short time.

(Fourth step)
The cut astringents (also called cut astringents) are primarily immersed in the sugar solution while being slowly thawed under refrigeration (step S4). Specifically, the cut astringent in a frozen state is immersed in a sugar solution maintained at the same temperature in a refrigerated environment of 0 ° C. to 10 ° C. for 10 hours to 24 hours, for example.

  By immersing cut astringency in sugar solution, flavor and texture are improved and preservation at room temperature is ensured.

  That is, the astringent taste of astringency cannot be completely removed only by de-astringency processing. On the other hand, by increasing the sugar content of astringency, the astringency is masked, and only the flavor unique to astringency can be utilized. In addition, by giving a high concentration sugar solution to astringency, unique soft physical properties can be obtained after drying. Furthermore, preservability can be improved by reducing the water activity.

  However, when immersed in a sugar solution with a high sugar content from the beginning, the fluidity of the sugar solution is further reduced because it is processed at a low temperature where the concentration is originally high and the fluidity of the sugar solution is low. Therefore, it is not possible to stably infiltrate the sugar solution up to the center of the cut astringency simply by dipping.

  Therefore, in this method, in order to spread the sugar solution having a high sugar content throughout the cut astringency, the solution is preliminarily immersed in a sugar solution having a lower sugar content before being immersed in the sugar solution having the desired high sugar content. Step immersion is adopted.

  As the sugar solution (primary sugar solution) in this step, for example, a sugar solution having a sugar content in the range of 25 to 35 (%) can be used, and the kind thereof is not limited. For example, sucrose, glucose, fructose, maltose, reduced starch saccharified product, or a sweetener such as trehalose or sorbitol can be dissolved in water to form a sugar solution.

  By slowly thawing the cut astringency, the cut astringent tissue is destroyed and softened. As a result, the primary sugar solution can easily penetrate into the cut astringency, and even if the primary sugar solution has low fluidity due to low temperature, the primary sugar solution can be spread throughout the cut astringency simply by soaking for 10 to 24 hours. Can do. Therefore, the sugar content of the whole cut astringency can be increased in a short time even at low temperatures.

  It is preferable to add calcium lactate to the primary sugar solution. For example, calcium lactate is added to the primary sugar solution at a concentration of 0.1 to 0.5% by weight. By adding calcium lactate, excessive softening and deformation of cut astringency can be prevented. Therefore, the shape of the cut astringency can be stably maintained, and handling becomes easy.

  In order to prevent discoloration due to oxidation, an appropriate amount of vitamin C may be added to the primary sugar solution as an antioxidant.

(Fifth step)
The primary soaked cut astringent is secondarily immersed in a sugar solution having a higher sugar content while reducing the pressure at 38 ° C. or lower (step S5). As the primary sugar solution penetrates the entire cut astringency by the primary immersion, the sugar solution having a high sugar content easily penetrates into the cut astringency. In this method, in order to increase the sugar content of the cut astringency to a desired sugar content in a short time, secondary dipping is performed while adjusting the temperature and pressure.

  As the sugar solution (secondary sugar solution) in this step, for example, a sugar solution having a sugar content in the range of 50 to 60 (%) can be used, and the kind thereof is not limited as in the case of the primary sugar solution. From the viewpoint of compatibility with astringent flavor, glucose is preferably used for the secondary sugar solution.

  The temperature of the secondary sugar solution is kept as high as possible up to 38 ° C. This is because when the temperature exceeds 38 ° C., astringent return occurs and soluble tannins may be generated in the cut astringent. By increasing the immersion temperature, the fluidity of the sugar solution is increased. Therefore, even if the secondary sugar solution has a higher sugar content and lower fluidity than the primary sugar solution, the fluidity of both can be brought closer by increasing the soaking temperature, and the secondary sugar solution to the cut astringent It can promote penetration.

  Further, the secondary immersion is performed under reduced pressure. For example, a cut astringent that has been subjected to primary immersion treatment may be introduced into a pressure vessel storing secondary sugar solution, and air in the pressure vessel may be sucked with a vacuum pump. The more the pressure is reduced, the higher the permeability of the secondary sugar solution to cut astringency, so the higher the degree of pressure reduction is preferable. However, as the degree of decompression is increased, a large facility is required and the running cost is increased. Therefore, the degree of pressure reduction is sufficient if it is at least lower than the normal pressure, and can be appropriately selected according to the specifications.

  In this step, the pressure may be continuously reduced, but it is preferably intermittently reduced. That is, the atmospheric pressure in the secondary immersion is alternately changed between reduced pressure and normal pressure. By doing so, the penetrability of the secondary sugar solution into the cut astringent can be increased without highly reducing the pressure, and the permeation can be performed efficiently in a short time.

  By performing such secondary dipping treatment, for example, the secondary sugar solution can be permeated throughout the cut astringency within 8 hours.

(Sixth step)
The cut astringent soaked in the secondary is dried at 38 ° C. or less (step S6). Specifically, the cut astringency is taken out from the secondary sugar solution, and the secondary sugar solution remaining on the surface of the cut astringency is washed away with water, and then put into a dryer to dry the cut astringency.

  The dryer is configured so that wind adjusted to a temperature of 38 ° C. or less is blown to the cut astringency, and the cut astringency is dried by air drying while preventing the occurrence of astringency return. The degree of drying is preferably dried until the water activity becomes 0.7 or less so that it can be stored at room temperature for a long period of time. Although drying time changes with the capability of a dryer, it can dry in about 12 hours-48 hours, for example.

  During drying, the surface of the cut astringency may be irradiated with ultraviolet rays. If it does so, the sanitary condition of the cut astringency during drying can be maintained with the favorable sterilization power of ultraviolet rays. Drying removes the moisture from the cut astringency and gives a soft dried fruit-like candy.

  You may perform finishing processes, such as spraying powdered sugar on the surface of the dried cut astringency. Finally, the obtained confectionery is individually packaged by a predetermined amount.

<Rice cake>
FIG. 2 shows the confectionery manufactured by the method described above.

  The water content of the candy cake is about 18% by weight, which is lower than that of the dried candy (water content is about 24% by weight). The water activity value of the candy confectionery is about 0.56, and long-term storage at room temperature is possible. Since the sugar concentration is high, it exhibits soft physical properties and can be easily eaten while enjoying the texture even for elderly people and children with weak chewing ability.

  Persimmon confectionery has a completely different appearance and flavor from conventional dried persimmons.

  FIG. 3 shows the results of a sensory test comparing strawberries and dried strawberries. In the sensory test, 10 male and female panelists (30 to 70 years old) taste sweet candy (Example) and dried persimmon (comparative example), and compare the appearance and flavor of the persimmon with each person's image. It was.

  As a result, 6 people in regard to the flavor of the dried potatoes and all the people in terms of appearance were evaluated to be the same or similar to the dried potatoes, whereas 10 people in the case of the confectionery were all flavored and looked like dried potatoes. Evaluated as clearly different (0/10).

  In particular, the flavor of candy sweets was highly evaluated for having a refreshing feeling with no stickiness compared to dried candy.

  As described above, according to the production method of the present invention, it becomes possible to mass-produce a new processed food that anyone can eat deliciously using astringency that is difficult to handle.

  In addition, the manufacturing method etc. concerning this invention are not limited to embodiment mentioned above, The other various structure is included. For example, in the embodiment, the concentration of the sugar solution is divided into two stages, but it may be divided into three or more stages.

Claims (3)

A method for producing processed foods using astringency,
A first step of de-biking raw astringent to insolubilize soluble tannin contained in the astringent;
A second step of freezing the astringent that has been removed
A third step of separating the frozen astringency;
A fourth step of primarily immersing the cut astringent in a primary sugar solution under refrigeration;
A fifth step of secondarily immersing the astringent persimmon soaked in a sugar solution having a higher sugar content than the primary sugar solution while reducing the pressure at 38 ° C. or lower;
A sixth step of drying the astringent soaked secondarily at 38 ° C. or lower until the water activity becomes 0.7 or lower ;
Manufacturing method. The manufacturing method according to claim 1,
A production method of adding calcium lactate to the sugar solution used in the fourth step. In the manufacturing method of Claim 1 or Claim 2,
In the fourth step, the astringent is immersed in a sugar solution maintained in a temperature range of 0 ° C. to 10 ° C. for 10 hours to 24 hours .