JP7713632B2 - Grape seed skin separation method - Google Patents

Description

The present invention relates to a method for separating grape seed skins.

Most of the pomace left over after grapes have been squeezed to make wine is discarded, and various attempts have been made to make effective use of it. However, pomace is not suitable for long-term storage as it will soon deteriorate (denaturation and/or putrefaction) due to microorganisms if left as is. In addition, pomace contains a mixture of skins and seeds, and it is preferable to separate these so that their respective uses can be developed.

For example, Patent Document 1 discloses a method for processing wine pomace (pomace) to make effective use of it, and a method for producing a food additive in which wine pomace (pomace) is put into a mixer to make a paste, then the paste-like pomace is crushed into a paste-like material using a mesh that only the seeds pass through, and the paste-like material is dried to make a fine powder. Patent Document 2 discloses a method in which the pomace is once frozen and stored, or dried in the sun or mechanically depending on the use, and then removed as needed, a small amount of water is added, and the pomace is lightly put through a mixer, after which the seeds are removed using a sieve with a mesh that is not large enough to pass through, and only the remaining paste-like portion is dried to make a fine powder.

Patent Document 3 discloses a method for producing a food additive material in which an approximately equal amount of water is added to the juice residue, and the mixture is boiled for approximately 30 minutes to an hour while adding water to retain moisture. In this method, after the boiling, the boiled residue and the boiled water are mixed using a stirrer with a rotating blade (e.g., a food processor), and then the mixture is strained using a mesh with a mesh size of approximately 2 mm to remove the seeds. Patent Document 4 describes a method for producing a dried powder of wild grape skin. In this method, the moisture content is adjusted by preliminary drying, and the seeds are removed by kneading the fruit with hands when the moisture content is 3% to 10%, or by pressing both sides of the spherical fruit when the moisture content is 30% to 55%.

JP 2010-193873 A JP 2013-183734 A JP 2009-165427 A JP 2015-167548 A

However, in the method of Patent Document 1, some paste passes through the mesh together with the seeds, and in the method of Patent Document 2, a large amount of the skin remains on the mesh together with the seeds, so there is a need to improve the method of separating the seeds and skin. Also, in the methods of Patent Documents 1 and 2, the work of putting the pomace through a mixer and crushing the paste-like juice residue with a mesh is inefficient.

In the method of Patent Document 3, when a food processor, which is exemplified as the mixer mentioned above, is used, the seeds may also be crushed, and there is a need to improve the method of separating the skin and seeds. In addition, the method of Patent Document 4 is inefficient because it involves kneading the fruit with hands and pressing both sides of the fruit.

Therefore, the present invention aims to provide a grape seed skin separation method that can efficiently separate the skin and seeds from grape pomace.

The grape seed skin separation method of the present invention includes a crushing step and a separation step. In the crushing step, the skin is crushed by rotating the stirring plate of a stirring device including a storage section for storing a dried residue obtained by drying a pomace having grape seeds and skin to a moisture content of 14% or less , a rotating shaft provided in the storage section in a vertically upright position, a stirring plate fixed to the rotating shaft, and a drive controller for adjusting the rotation speed of the stirring plate , and the temperature of the dried residue at the start of crushing is at most 30° C. In the separation step, after the crushing step, the seeds and the crushed skin are separated by a net having a mesh size smaller than the diameter of the seeds. The stirring plate is either one of a stirring blade having both plate surfaces intersecting with the vertical direction, or a rotating plate formed in a disk shape with a circular center fixed to the rotating shaft and having unevenness formed on an upper surface intersecting perpendicularly with the vertical direction.

The stirring blade is preferably fixed to the rotating shaft at its center in the longitudinal direction . The stirring blade preferably has a blade formed along the longitudinal direction and rotates in the direction in which the blade faces.

The stirring device preferably has a pair of stirring blades that intersect at the center in the longitudinal direction when viewed from above .

The agitator equipped with a rotating plate preferably rotates the rotating plate and causes the dried residue on the rotating plate to collide with the inner surface of the side wall of the storage section .

It is preferable that the method further includes a drying step in which the juice residue is dried to a moisture content of 14% or less while being heated, and a temperature reducing step in which the dried residue obtained by the drying step is cooled to 30°C or less , and the dried residue cooled in the temperature reducing step is subjected to a crushing step .

The grinding process may involve intermittently cooling the dry residue.

The grinding process may involve intermittent stirring of the dry residue.

According to the present invention, the skins and seeds are separated from the grape pomace more reliably and efficiently.

FIG. 1 is a flow diagram of an embodiment of a method for separating grape seed skins. FIG. FIG. 1 is a flow diagram of a stirring process. FIG. 2 is a schematic partial cross-sectional view of the stirring device. FIG. 2 is a schematic explanatory diagram of an agitating blade. FIG. 2 is a schematic diagram of a separation device. FIG. 4 is a schematic, partially sectional view of another stirring device.

As shown in FIG. 1, the grape seed and skin separation method according to one embodiment of the present invention separates the residue (hereinafter referred to as pomace) 13 obtained by squeezing juice 12 from grapes 11 in a juicing process S1 into seeds 16 and skins 17. The pomace 13 contains seeds 16, skins 17, and water. The skins 17 of the pomace 13 may contain seeds 16, and in some cases the seeds 16 are covered by the skins 17.

The pomace processing process RS, which separates the seeds 16 and the skin 17, includes a drying process S2, a temperature-reducing process S3, a crushing process S4, and a separation process S5. The drying process S2 dries the pomace 13. The pomace 13 dried by the drying process S2 is hereinafter referred to as the dried residue and is given the reference number 18. The temperature-reducing process S3 reduces the temperature of the dried residue 18 obtained by the drying process S2. That is, the temperature-reducing process S3 reduces the temperature of the dried residue 18. In the dried residue 18, many of the skins 17 contain seeds 16. The crushing process S4 crushes the skin 17 by stirring the dried residue 18. The crushing process S4 selectively crushes only the skin 17, so as not to crush the seeds 16. As a result, both the skin 17 that does not contain the seeds 16 and the skin 17 that covers the seeds 16 are crushed into fine pieces. In the following description, the dried residue 18 that has undergone the crushing step S4 is referred to as the crushed residue and is given the reference number 19. In the separation step S5, the seeds 16 and the peel 17 are separated after the crushing step S4. The peel 17 separated by the juice residue processing step RS is in the form of fine particles, and although it has an irregular shape, the size is generally uniform.

In this example, the seeds 16 and skins 17 are obtained by separating them from the pressed residue 13, but if the dried residue 18 is available, the seeds 16 and skins 17 may be obtained by separating them from the dried residue 18. In that case, the drying step S2 may not be necessary. Also, although the grape seed skin separation method in this example has a temperature-reducing step S3, this temperature-reducing step S3 may not be necessary.

Each step of the pomace processing step RS will be described below. The drying device 21 shown in FIG. 2 is an example of a device that performs the drying step S2. The drying device 21 includes a pressure reduction mechanism 23, a temperature adjustment mechanism 24, and a stirring mechanism 25, and includes a container body 28 that contains the pomace 13. The drying device that performs the drying step S2 is not limited to this example, and may not include at least one of the pressure reduction mechanism, temperature adjustment mechanism, and stirring mechanism as long as it can dry the pomace 13. However, from the viewpoint of evenly and efficiently drying the entire amount of the contained pomace 13, it is preferable that the drying device includes at least one of the pressure reduction mechanism, temperature adjustment mechanism, and stirring mechanism, as in this example, and it is even more preferable that the drying device includes all of them. The drying device may be a commercially available drying device.

The container body 28 has a cylindrical first wall plate 28a and a pair of disk-shaped second wall plates 28b provided at each end of the first wall plate 28a, but the shape of the container body 28 is not limited to this example and may be, for example, a cube. Note that one of the pair of second wall plates 28b or the first wall plate 28a has an opening and closing opening for inserting and removing the juice residue 13 and the dried residue 18 obtained by drying, but this is omitted in Figure 2 to avoid cluttering the drawing.

The volume of the container body 28 is not particularly limited, and the amount of juice pomace 13 that can be placed in the container body 28 is also not particularly limited. In this example, the volume is 500 kg, and approximately 350 kg of juice pomace 13 can be dried. In this way, the drying process S2 is efficient because it can be performed even in a large drying device.

The decompression mechanism 23 decompresses the inside of the container body 28 by sucking the gas inside the container body 28. This allows drying to proceed more efficiently at a lower temperature. The temperature adjustment mechanism 24 is for heating the juice residue 13 contained in the container body 28 via the container body 28. The temperature adjustment mechanism 24 includes a heater 31 arranged on the outer surface of the container body 28 and a temperature controller 32 that switches the heating of the heater 31 on and off and adjusts the temperature when the heating is on. The temperature controller 32 adjusts the temperature of the juice residue 13 contained in the container body 28 to a desired temperature via the container body 28. Note that, regardless of the presence or absence of the temperature adjustment mechanism 24, a temperature sensor (not shown) that detects the temperature inside the container body 28 may be provided, and the temperature detected by this temperature sensor may be considered as the temperature of the juice residue 13.

A temperature sensor (not shown) for detecting the temperature may be provided in the container body 28, and feedback control may be performed by the temperature controller 32 based on the temperature detected by the temperature sensor. In that case, the temperature set by the temperature controller 32 may be regarded as the temperature of the pomace 13 in the drying process S2. In the case where feedback control is not performed, the temperature of the pomace 13 gradually increases as the drying proceeds, i.e., as the moisture content decreases, as shown in Table 1. However, even if the temperature exceeds 100°C under reduced pressure, there is no particular problem in terms of reliably separating the seeds 16 and the peel 17. Table 1 shows data in the case where feedback control is not performed. The relationship between the moisture content and temperature of the pomace 13 when 120 kg of Niagara (harvest year 2018) is dried under reduced pressure is shown. The "drying time" (unit: min) in Table 1 is the time from the start of the decompression, which is the start of drying, to the time of sampling. The implementation date is November 22, 2019. No temperature adjustment was performed. The temperature of the pomace 13 was 50°C or higher in all cases, and as the moisture content decreased, the temperature of the pomace 13 increased. Note that in this specification, the moisture content (%) is a percentage calculated by {(x-y)/x} x 100, where x is the mass of the object before drying and y is the mass of the object after drying, and is calculated using a heat-dry moisture meter ML-50 manufactured by A&D Co., Ltd.

The stirring mechanism 25 is for stirring the juice residue 13, and includes a stirring unit 35, a motor 36, a drive controller 37, etc. The stirring unit 35 has a stirring blade 41, a rotating shaft 42, and a support member 43. The rotating shaft 42 is disposed generally horizontally and is rotatable relative to the second wall plate 28b. The stirring blade 41 is fixed to the rotating shaft 42 by a rod-shaped support member 43, and rotates together with the rotating shaft 42 along the inner wall of the first wall plate 28a by the motor 36. The drive controller 37 controls the motor 36 to switch the rotation of the stirring blade 41 on and off, switch the rotation direction of the stirring blade 41, and adjust the rotation speed of the stirring blade 41.

The agitator blade 41 is formed in a rectangular plate shape, with its long side aligned along the direction from one of the pair of second wall plates 28b to the other. As a result, the agitator blade 41 rotates in a position along the inner wall of the first wall plate 28a to scrape off the juice residue 13. However, the shape of the agitator blade 41 is not limited to this example. The number of agitator blades 41 is not limited to three as in this example.

In FIG. 2, to avoid complicating the drawing, the temperature controller 32, the motor 36, and the drive controller 37 are only shown in FIG. 2(A). The drying device 21 is a so-called horizontal drying device in which the second wall member 28b of the container body 28 is in a vertically upright position, but it may also be a so-called vertical drying device in which the first wall plate 28a is in a vertical position.

The juice residue 13 to be subjected to the drying step S2 may be in a so-called raw state after the juice has been squeezed out, or may be in a frozen state. In this way, the drying method of the juice residue 13 is not limited, and ventilation drying, cold air drying, freeze drying, reduced pressure drying, heat drying, reduced pressure heat drying, sun drying, etc. can be used.

The degree to which the pomace 13 is dried in the drying step S2 is not particularly limited, but from the viewpoint of more reliably and finely grinding the peels 17 in the grinding step S4, it is preferable to dry the pomace 13 until the moisture content is 14% or less. In this example, the pomace 13 is dried so that the moisture content is in the range of 0.2% to 14%, and the grinding step S4 grinds the dried residue 18 with this moisture content. Note that in order to suppress changes in the components of the peels 17, etc., it tends to be preferable to dry at low temperatures for a long time rather than high temperatures for a short time.

The temperature-reducing step S3 may be performed in the drying device 21, or may be left to cool (cooled) after being removed from the drying device 21, or may be performed using a cooling device (not shown). For example, when performed using a drying device 21 equipped with a temperature controller 32, the temperature of the dried residue 18 can be reduced by cooling it via the container body 28. When the temperature is reduced by leaving it to cool or using a cooling device, the temperature can be reduced by storing the dried residue 18 in a container such as a bag, box, can, or container. The material of these containers is not particularly limited and may be paper, plastic, metal, wood, etc.

In the temperature-reducing step S3, the temperature of the dried residue 18 is reduced to a temperature lower than the temperature of the pomace 13 in the drying step S2. As a result, in the crushing step S4, even if the dried residue 18 has the same moisture content, crushing of only the peels 17 is more reliable, and the peels 17 are crushed into finer and more uniformly sized particles. A temperature lower than the temperature of the pomace 13 in the drying step S2 means a temperature lower than the temperature of the pomace 13 at the end of the drying step S2.

In the crushing step S4, it is preferable to crush the dried residue 18 at a temperature of at most 30°C, and therefore, in the temperature-reducing step S3, it is preferable to cool the dried residue 18 to at most 30°C, i.e., to 30°C or less. When the temperature of the squeezed pomace 13 is raised to a temperature higher than 30°C in the drying step S2, it is preferable to cool it to 30°C or less in the temperature-reducing step S3. This allows the dried residue 18 to be provided to the crushing step S4 at a low temperature. In the crushing step S4, it is preferable to crush the dried residue 18 having a moisture content of 14% or less, and this allows the fruit peel 17 to be crushed more effectively.

In the grinding step S4, the temperature of the dried residue 18 increases (is heated) due to stirring the larger the amount of dried residue 18 stored in the grinding device and the longer the grinding time. In the case of a so-called continuous process in which the dried residue 18 is continuously or intermittently supplied to the grinding device, the grinding time is the residence time of a specific dried residue 18 in the grinding device. The higher the temperature of the dried residue 18 in the grinding step S4, the more likely it is that the grinding of the peels 17 will be suppressed. Therefore, in the grinding step S4, it is preferable to stir the dried residue 18 while keeping the temperature low, and it is more preferable to stir the dried residue 18 at a temperature lower than the temperature of the juice residue 13 at the end of the drying step S2.

In the grinding step S4, it is preferable to keep the temperature of the dried residue 18 at 30°C or less, i.e., 30°C or less. However, it is not necessary to keep the temperature at 30°C or less during the grinding step S4. For example, if the temperature of the dried residue 18 is 30°C or less at the start of the grinding step S4, the grinding of the peel 17 is sufficiently improved. In this way, the temperature of the dried residue 18 at 30°C or less may be only a part of the time during the grinding step S4. In this example, the temperature of the dried residue 18 at the start of the grinding step S4 is set to a range of -12.8°C to 30°C, but this lower limit of -12.8°C depends on the performance of the cooling device used, and it is considered that the same effect can be obtained at a temperature lower than -12.8°C as when it is in the range of -12.8°C to 30°C. However, at an extremely low temperature, condensation may occur, and it is preferable to set the temperature taking into consideration the balance with the occurrence of condensation. In addition, in the crushing step S4, the temperature of the dried residue 18 gradually increases, so even if the dried residue 18 is in a frozen state in the temperature decreasing step S3, it may be in a thawed state in the crushing step S4.

In the grinding step S4, the dried residue 18 may be cooled intermittently. This is because intermittent cooling has an energy-saving effect compared to continuous cooling, while the grinding efficiency of the peels 17 is about the same.

The grinding step S4 may be continuous stirring, or may be intermittent stirring of the dried residue 18. In the case of intermittent stirring, the grinding step S4 includes a continuous stirring step S4a for continuously (continuously) stirring the dried residue 18, and a stirring stop step S4b for stopping the continuous stirring step S4a, as shown in FIG. 3. The continuous stirring step S4a is a step for grinding the peel 17, and while grinding is continued, the ground peel 17 becomes unevenly distributed at the bottom of the stored dried residue 18, and the unground and less ground peel 17 is located at the top. The stirring stop step S4b is for eliminating such uneven distribution. By the stirring stop step S4b, the large peel 17 unevenly distributed at the top of the dried residue 18 sinks to the bottom of the dried residue 18. As a result, by performing the continuous stirring step S4a again, the grinding of the peel 17 by the continuous stirring step S4a proceeds more effectively. If grinding is performed using a stirring device 91 (see FIG. 7) described below, stirring can be performed continuously and does not need to be performed intermittently.

In FIG. 3, the grinding process S4 has a determination process S4c after the continuous stirring process S4a. The determination process S4c determines whether the peels 17 have reached the desired grinding level. If the determination process S4c returns a positive result, the process proceeds to the separation process S5, and if the determination process S4c returns a negative result, the process returns to the stirring stop process S4b. Note that if the determination process S4c returns a negative result and the unground or not-yet-ground peels 17 sink to the bottom during the determination process S4c, the process may proceed to the continuous stirring process S4a after the determination process S4c without passing through the stirring stop process S4b.

The crushing step S4 can be performed, for example, by a stirring device 51 shown in FIG. 4. The stirring device 51 is an example of a device that crushes only the peel 17 by stirring the dried residue 18. It includes a container 52, which is a storage section that stores the dried residue 18, a stirring mechanism 53, and a temperature control mechanism 56. However, the temperature control mechanism 56 is not necessary. The container 52 includes a cylindrical container body 52a that stores the dried residue 18, and a lid 52b, and an exhaust port 52c is formed in the lid 52b. The exhaust port 52c is for preventing the pressure inside the container 52 from increasing excessively. It is preferable to provide a filter in the exhaust port 52c to prevent the crushed peel 17 from passing through.

The stirring mechanism 53 is for stirring the dried residue 18, and includes a stirring unit 57, a motor 58, a drive controller 61, and the like. The stirring unit 57 is disposed in the container 52, and has a rotating shaft 62, a support member 63, and stirring blades 66, 67. The support member 63 is fixed to the inner bottom of the container body 52a, and the rod-shaped rotating shaft 62 is rotatably mounted on the support member 63 in a vertically upright position. The stirring blades 66, 67 are an example of a stirring plate, and are fixed to the rotating shaft 62. As a result, the stirring blades 66, 67 rotate integrally with the rotating shaft 62 by the motor 58. The drive controller 61 controls the motor 58 to switch the rotation of the stirring blades 6, 67 on and off, and adjust the rotation speed of the stirring blades 66, 67. The rotation of the stirring blades 66, 67 stirs the dried residue 18, thereby crushing the fruit peel 17. It has been confirmed that the pericarp 17 can be crushed when a large amount of dried residue 18 (6 kg) is placed in the container 52. Moreover, crushing of the seeds 16, which are harder than the pericarp 17, is suppressed.

As shown in Figs. 4 and 5, the stirring blades 66 and 67 are formed in a rectangular plate shape, and the plate surfaces SA and SB are arranged so that they face in each of the up and down directions. As a result, the stirring blades 66 and 67 have surfaces along a plane where the plate surfaces SA and SB intersect with the vertical direction. The plate surface facing up is marked with the symbol SA, and the plate surface facing down is marked with the symbol SB. By arranging the plate-shaped stirring blades 66 and 67 in this manner, the dried residue 18 is stirred by shear. In this way, the stirring device 51 applies active shear to the dried residue 18 by the plate-shaped stirring blades 66 and 67 as a crushing stress greater than the centrifugal force or the gravity on the dried residue 18. The plate surfaces SA and SB facing in each of the up and down directions may be inclined with respect to the vertical direction as long as the direction has a vertical component. Note that the support member 63 is omitted from the illustration in Fig. 5.

The stirring blades 66 and 67 have a rectangular shape with a narrower width from the center toward both ends in the longitudinal direction, and when viewed from above as shown in FIG. 5, they cross at a 90° angle in the longitudinal center. This center is fixed to the rotating shaft 62. The stirring blades 66 and 67 have blades 66a and 67a with gradually decreasing thickness formed along the longitudinal direction, and by rotating the stirring blades 66 and 67 together in the direction in which the blades 66a and 67a face, a larger shear force is likely to be generated. The stirring blades 66 and 67 are not limited to crossing each other in the longitudinal center, and may face in the same direction.

The agitator 51 is provided with two pairs of agitator blades 66 and agitator blades 67, which are arranged at a distance in the vertical direction. This allows the crushing force to be applied to the peel 17 more efficiently than when there is only one pair. The number of pairs of agitator blades 66 and agitator blades 67 is not limited to two pairs, and may be three or more pairs. The agitator blades 66 and agitator blades 67 do not have to be the same size or shape. The agitator blades 66 and agitator blades 67 do not have to be conceptualized as pairs, in which case the number of agitator blades 66 and agitator blades 67 may be the same or different. When at least one of the agitator blades 66 and agitator blades 67 is provided in multiples, the agitator blade 66 or agitator blade 67 arranged at the bottom may be shaped to scrape up the dried residue 18. An example of a shape that scrapes up the dried residue 18 is a shape in which at least a part of the plate surface SA is inclined relative to the horizontal.

In this example, the rotation speed of the agitator blades 66, 67 is set to a range of 200 rpm to 800 rpm. However, the rotation speed of the agitator blades 66, 67 may be set appropriately depending on the progress of crushing of the peel 17, etc.

The crushed residue 19 obtained by crushing in the crushing step S4 (see FIG. 1) is a mixture of seeds 16 and finely granulated pericarp 17. The crushed residue 19 is subjected to a separation step S5 (see FIG. 1) and separated into the seeds 16 and pericarp 17.

The separation device 71 shown in FIG. 6 is an example of a device that performs the separation step S5. The separation device 71 is a sieve device that includes a supply section 72 to which the crushed residue 19 is supplied, a net 73, a receiving section 76, and a vibration mechanism 77. The net 73 is disposed in the open lower part of the supply section 72 and is vibrated by the vibration mechanism 77. The mesh size (not shown) of the net 73 is smaller than the diameter of the seeds 16, so that the seeds 16 remain on the net 73, and the pericarp 17 crushed to a size smaller than the seeds 16 by the agitator 51 passes through the mesh size of the net 73 and is guided to the receiving section 76 provided below the net 73. In this way, the pericarp 17 and the seeds 16 are separated. In this example, for example, the seed division is 2.36 mm or more, and the pericarp division is less than 2.36 mm, but the boundaries of the size classification divisions are not limited to this and can be set according to the size of the seeds 16, etc.

An outlet 76a is formed in the lower part of the side wall of the receiving part 76 for the peels 17 to exit, and the bottom plate 76b is inclined so as to be lower toward the outlet 76a. This allows the peels 17 guided into the receiving part 76 to smoothly exit through the outlet 76a to the outside and be collected in a peel collection container 78. The seeds 16 on the net 73 are collected in a seed collection container (not shown). In this way, the finely granulated peels 17 and the uncrushed seeds 16 are collected separately.

According to the above-mentioned configuration, the obtained pericarp 17 is reliably separated from the seeds 16 and is efficiently obtained in the form of fine granules. As a result, the bulk density of the obtained pericarp 17 is 0.50 g/ ^cm3 , which is more than ^three times the bulk density of the dried residue 18, which is 0.14 g/cm3, making it easier to secure a storage space and to transport. In a method in which the squeezed pomace 13 is made into a paste and then dried, the fine powder may become hard lumps when the paste is dried, but the method of this example does not cause such hard lumps.

In the above juice residue processing step RS, the agitator for performing the crushing step S4 is not limited to the above-mentioned agitator 51 (see FIG. 4), and may be any commercially available product as long as it can selectively crush the peels 17 of the dried residue 18 contained in the container. For example, the agitator 91 shown in FIG. 7 includes a cylindrical container 92 in which the dried residue 18 is contained, and a stirring mechanism 93. A hopper 92a is provided on the top surface of the container 92, and the dried residue 18 is supplied into the container 92 through this hopper 92a. An outlet 92b for the crushed residue 19, which is a mixture of the seeds 16 and the crushed peels 17, is formed on the side wall of the container 92.

The stirring mechanism 93 includes a stirring unit 96, a motor 97, and a drive controller 98. The stirring unit 96 is disposed inside the container 92. The stirring unit 96 is provided with a rotating plate 101 formed in a disk shape in a generally horizontal position with each plate surface facing up and down. The rotating plate 101 is an example of a stirring plate that stirs the dried residue 18. The rotating shaft 102 is provided on the inner bottom surface of the container 92 in a vertically upright position so as to be freely rotatable in the circumferential direction. The rotating plate 101 has a circular center fixed to the rotating shaft 102, and the upper surface 101a intersects perpendicularly to the vertical direction. The upper surface 101a has fine irregularities. When the rotating plate 101 rotates in the circumferential direction, the dried residue 18 on the rotating plate 101 collides with the inner side wall of the container 92 due to centrifugal force, and the peel is crushed by the stress (impact) from the rotating plate 101. The pericarp 17 may also be crushed, for example, due to collisions between the pericarp 17 or due to unevenness of the upper surface 101a. However, the seeds 16 are prevented from being crushed. In this way, crushed residue 19 is obtained. By opening the outlet 92b while rotating the rotating plate 101, the crushed residue 19 is guided to the outside.

The lower the temperature in the cooling step S3, the higher the rotation speed of the agitator blades 66, 67 (see FIG. 4) and the rotating plate 101 in the crushing step S4, and the lower the moisture content of the dried residue 18 subjected to the crushing step S4, the smaller the size of the peels 17 tends to be crushed. Therefore, by adjusting at least one of these, the peels 17 can be crushed to the desired size. However, if the rotation speed of the agitator blades 66, 67 (see FIG. 4) and the rotating plate 101 is excessively high, the seeds 16 may also be crushed, so it is preferable to set the rotation speed high within a range in which the seeds 16 are not crushed.

The grape variety is not particularly limited, and this example is effective for Vitis labrusca, Vitis vinifera, Vitis amurensis, Vitis coignetiae, other species, or all hybrids of these. For example, Niagara, Delaware, Portland, New Niagara, Neo Muscat, Shine Muscat, Kyoho, Concord, Pione, Steuben, Muscat of Alexandria, Kaiji, Ruby Roman, Aurora Black, Campbell Early, Buffalo, Aki Queen, Sun Verde, Aki Suzu, Queen Nina, Sunny Dolce, Black Bead, Fuji Minoru, King Delaware, Oriental Star, Golby, Suiho, Yoho, Seto Giants, Sunny Rouge, Beni Nanyo, Red Niagara, Tabiji, Rosario Bianco, Pittero Bianco, Shitama, Summer Black, Izu Nishiki, Black Olympia, Mills, North Red, North Black, Himrod Seedless, Beni Izu, Takasumi, Ryuho, Risamart, Seibel 9110, Seibel 5279, Seibel 13053, Rondo, Regent, Acolon, Kai Noir, Kai Blanc, Yama Sauvignon, Bijou Noir, Armonoir, Mondebrier, Colline Verte, Black Queen, Ryugan, Kiyomi, Kiyomi, Yamayuki, Hokujun, Adirondack, Koshu, Muscat Berry A, Saint-Semillon, Shinano Riesling, Little Prince, New York Muscat, Berry Alicante A, Yamabudo, Black Pegar, White Pegar, Chardonnay, Pinot Blanc, Sauvignon Blanc, Chenin Blanc, Semillon, Riesling, Kerner, Silvaner, Bacchus, Muscat, Morio Muscat, Muscat Ottonel, Albariño, Gewürztraminer, Pinot Gris, Viognier, Macabeo, Parellada, Xarello, Ugni Blanc, Torrontes, Palomino, Petit Manseng, Glera, Pedro Ximenez, Verdejo, Marsanne, Muscadet, Moscato Bianco, Muller-Thurgau, Sarajenge, Furmint, Ortega, Perrelet, Siegerrebe, Fuchselrebe, Scheurebe, Muskateller, Solaris, Gutedel, Knobling, Muscaris, Grüner Veltliner, Gros Manseng, Savagnin, Schönberger, Eilen, Welsh This method is effective for a wide variety of grapes, including Riesling, Garganega, Cabernet Sauvignon, Cabernet Franc, Sangiovese, Pinot Noir, Syrah, Tannat, Zweigelt, Dornfelder, Trollinger, Barbera, Petit Verdot, Merlot, Lemberger, Pinot Meunier, Rothberger, Cinsault, Zinfandel, Nebbiolo, Malbec, Mourvedre, Portugieser, Tempranillo, Helfensteiner, Saperavi, Frueburgunder, Cabernet Mitos, Cabernet D'orsa, Cabernet Cubine, Aglianico, Gamay, Carignan, Grenache, Carmenere, Pinotage, and Rondinella. The method is also effective for grapes of any variety, regardless of the grape origin, harvest year, storage container for the pomace 13, or storage container for the dried pomace 18.

[Example 1] to [Example 5]
Using a drying device, a cooling device (not shown), an agitator, and a separator 71, seeds 16 and peels 17 were obtained from the pomace 13, and these were used as Examples 1 to 5. The drying device was the same as the drying device 21, except that it did not have a temperature control mechanism 24. The agitator had the same configuration as the agitator 51, but did not have a temperature control mechanism 56, and the total number of the agitator blades 66 and the agitator blades 67 was four. The pomace 13 fed to the drying device was the same as described below. In Examples 1 to 5, dried residues 18 with different moisture contents were obtained, and each was fed to the agitator to grind the peels 17. The conditions are shown in Table 2. In the "Crushing process time" column in Table 2 and subsequent tables, "total XX" refers to the case where the rotation speed, temperature, etc. were changed during the crushing process, and indicates the total time of stirring. In addition, in each table in Table 2 and subsequent tables, "processed mass" refers to the mass fed to the process in which the process is performed. In each process, there were cases where the mass obtained by a process was less than the processed mass due to losses caused by adhesion to the equipment of that process, but these differences were very small and could be ignored.
<Juice residue>
Drying date: July 21, 2020 Grape variety: Niagara Harvest year: 2018 Origin: Hokkaido Weight of pomace (kg): 111.5
Moisture content (%); 64.9
Storage container: 500kg container Storage temperature (°C): -17

The crushed state of the pericarp 17 obtained in Examples 1 to 5 was visually evaluated based on the standard of Example 1. The evaluation criteria were as follows, and the evaluation results are shown in Table 2 as "Crushing Evaluation".
Standard and 0: The peel is uneven in size, but crushed. +1: The peel is finer and more uniform in size than the standard, which is good. +2: The peel is finer and more uniform in size than the standard, which is very good.

The processing speed (feed rate of crushed residue 19) in the separator 71 for Examples 2 to 5 is shown in the "Processing speed" column of the "Separation process" in Table 3. After the crushing process, the mixture was divided once, and half of the mixture was classified using the separator 71 to confirm the proportion of each section. The section over 2.36 mm ("over" means "larger") was used as the seed section. The proportion of seeds 16 between 2.36 mm and 4.75 mm was calculated by dividing the mixture (manual tapping test) to confirm whether the seeds 16 were properly separated. These results are shown in Table 3. The numerical ranges indicated by "-" in each table include the endpoints before and after "-". "Seed purity" in Table 3 and Tables 9 and 10 described below is a percentage value (unit: %) calculated by (seed mass (unit: g) / seed section mass (unit: g)) x 100. The "seed section mass" is the mass of "2.36 mm over" after reduction, and the "seed mass" is the mass of the parts that were visually recognized as seeds taken from the "seed section mass" and measured.

[Example 6] to [Example 12]
Examples 6 to 12 were carried out in which the conditions of the temperature of the dried residue 18 at the start of the grinding process and the rotation speed of the stirring blades 66, 67 in the grinding process were different from each other. The respective conditions are shown in Table 4, and the other conditions were the same as those of Example 1. The squeezed pomace 13 subjected to the drying device was the same in all cases, and was as follows.
<Juice residue>
Drying date: July 31, 2019 Grape variety: Niagara Harvest year: 2018 Origin: Hokkaido Weight of juice residue (kg): 151.3
Moisture content (%); 67.8
Storage container: 500kg container Storage temperature (°C): -17

Evaluation was performed using the same method and criteria as in Example 1. The results are shown in Table 4.

[Example 13] to [Example 14]
Examples 13 and 14 were carried out in which the temperature of the dried residue 18 at the start of the grinding step was different from each other. In Example 13, the temperature lowering step was not carried out. The respective conditions are shown in Table 5, and the other conditions were the same as in Example 1. The squeezed pomace 13 supplied to the drying device was the same in all cases, and was as follows.
<Juice residue>
Drying date: November 6, 2019 Grape variety: Niagara Harvest year: 2019 Origin: Hokkaido Weight of juice residue (kg): 156.1
Moisture content (%); 67.6
Storage container: 500kg container Storage temperature (°C): -17

Evaluation was performed using the same method and criteria as in Example 1. However, no manual tapping test was performed. The results are shown in Table 5.

[Example 15] to [Example 18]
Seeds 16 and pericarp 17 were obtained from the following pomace 13 under the conditions shown in Table 6, and these were used as Examples 15 to 18. The other conditions were the same as those of Example 1. Examples 15, 16, and 18 were carried out three times using the same pomace 13 under the same conditions, and the Example numbers in the table are given subnumbers of "-1" to "-3", respectively.

<Pomace of Example 15>
Drying date: May 22, 2019 Grape variety: Niagara Origin: Hokkaido Weight of juice residue (kg): 140.1
Moisture content of pomace (%): 61.4
Harvest year: 2018 Storage container: 500 kg container Storage temperature (℃): -17
<Pomace of Examples 16 and 17>
Drying date: September 25, 2019 Grape variety: Niagara Origin: Hokkaido Weight of pressed residue (kg): 120.6
Moisture content of pomace (%): 67.1
Harvest year: 2018 Storage container: 500 kg container Storage temperature (℃): -17
<Pomace of Example 18>
Drying date: September 27, 2019 Grape variety: Niagara Origin: Hokkaido Weight of juice residue (kg): 132.2
Moisture content of pomace (%): 64.8
Harvest year: 2017 Storage container: 20 kg container Storage temperature (℃): -17

The evaluation was performed using the same method and evaluation criteria as in Example 1. The results of the crushing evaluation and classification are shown in Table 6, and the results of the manual tapping test are shown in Table 7. The values in parentheses in the "Processing mass" column of the "Separation process" in Table 6 indicate the recovered mass obtained in the separation process because the processing mass was not measured. The "Total mass" (unit: g) in Table 7 is the sum of "4.75 mm over", "2.36 mm over seeds", and "2.36 mm over remainder", and the "Seed purity" in Table 7 was calculated by replacing the seed division mass (unit: g) in the above-mentioned calculation formula for calculating the seed purity in Table 3 with the value obtained by subtracting the mass of "4.75 mm over" from the mass of "2.36 mm over".

[Example 19] to [Example 20]
Seeds 16 and pericarp 17 were obtained from the following squeezed pomace 13 under the conditions shown in Table 8, and these were used as Examples 19 and 20. The other conditions were the same as in Example 1.

<Juice residue>
Drying date: September 24, 2020 Grape variety: Niagara Origin: Yamagata Prefecture Weight of juice residue (kg): 94.3
Moisture content of pomace (%): 68.3
Harvest year: 2020 Storage container: 20 kg container Storage temperature (℃): -17

Except for the fact that the manual tapping test was not performed, the evaluation was performed using the same method and evaluation criteria as in Example 1. The evaluation results are shown in Table 8.

[Example 21] to [Example 24]
Seeds 16 and pericarp 17 were obtained from the following squeezed pomace 13 under the conditions shown in Table 9, and were used as Examples 21 to 24. In the crushing process of these Examples, stirring was performed intermittently, and two continuous stirring steps were performed. The other conditions were the same as those of Example 1.

<Juice residue>
Drying date: October 4, 2018 Grape variety: Zweigelt Origin: Hokkaido Weight of pressed residue (kg): 187.2
Moisture content of pomace (%): 74.1
Harvest year: 2015 Storage container: 500 kg container Storage temperature (℃): -17

Evaluation was performed using the same method and evaluation criteria as in Example 1. Note that the manual tapping test was performed only for Example 21. The evaluation results are shown in Table 9.

[Example 25] to [Example 28]
Seeds 16 and pericarp 17 were obtained from the following squeezed pomace 13 under the conditions shown in Table 10, and were used as Examples 25 to 28. In the crushing process of these Examples, stirring was performed intermittently, and three consecutive stirring steps were performed. The other conditions were the same as those of Example 1.

<Juice residue>
Drying date: August 19, 2020 Grape variety: Campbell Early Origin: Miyazaki Prefecture Harvest year: 2020 Mass of pomace (kg): 101.9
Moisture content of pomace (%): 71.8
Storage container: 20 kg container Storage temperature (℃): -17

Evaluation was performed using the same method and criteria as in Example 1. The evaluation results are shown in Table 10.

[Example 29] to [Example 31]
Seeds 16 and pericarp 17 were obtained from the following squeezed pomace 13 under the conditions shown in Table 11, and these were used as Examples 29 to 31. In the crushing process of these Examples, stirring was performed intermittently, and two continuous stirring steps were performed. The other conditions were the same as those of Example 1.

<Juice residue>
Drying date: September 15, 2020 Grape variety: Buffalo Origin: Hokkaido Harvest year: 2020 Mass of pomace (kg): 88.0
Moisture content of pomace (%): 74.9
Storage container: 20 kg container Storage temperature (℃): -17

The evaluation was performed using the same method and evaluation criteria as in Example 1, except that the manual tapping test was not performed. The evaluation results are shown in Table 11.

[Example 32]
Seeds 16 and pericarp 17 were obtained from the following squeezed pomace 13 under the conditions shown in Table 12, and designated as Example 32. In these Examples, the grinding step was performed by intermittent stirring, and two continuous stirring steps were performed. The other conditions were the same as those in Example 1.

<Juice residue>
Drying date: October 3, 2020 Grape variety: Muller-Thurgau Origin: Hokkaido Harvest year: 2020 Mass of pomace (kg): 116.5
Moisture content of pomace (%): 77.6
Storage container: 20 kg container Storage temperature (℃): 2

The evaluation was performed using the same method and evaluation criteria as in Example 1, except that the manual tapping test was not performed. The evaluation results are shown in Table 12.

[Example 33]
Seeds 16 and pericarp 17 were obtained from the following squeezed pomace 13 under the conditions shown in Table 12, and this was designated as Example 33. The grinding step was carried out using a stirring device 91, and the rotation speed of the rotating plate 101 is shown in Table 13. The other conditions were the same as those of Example 1.

<Juice residue>
Drying date: November 29, 2019 Grape variety: Niagara Origin: Hokkaido Harvest year: 2019 Mass of pomace (kg): 120.0
Moisture content of pomace (%): 67.6
Storage container: 500kg container Storage temperature (°C): -17

Evaluation was performed using the same method and evaluation criteria as in Example 1. The evaluation results are shown in Table 13. The "Seed purity" in Table 13 was calculated by replacing the "seed division mass" (unit: g) in the aforementioned calculation formula for calculating the seed purity in Table 3 with the mass of "2.36 mm to 4.75 mm."

11 Grape 12 Fruit juice 13 Juice residue 16 Seed 17 Pericarp 18 Drying residue 19 Grinding residue 21 Drying device 24 Temperature control mechanism 51,91 Stirring device 52 Container 53,93 Stirring mechanism 62,102 Rotating shaft 66,67 Stirring blade 71 Separation device 101 Rotating plate RS Juice residue treatment process S1 Squeezing process S2 Drying process S3 Temperature lowering process S4 Grinding process S5 Separation process

Claims (8)

a grinding step in which a grinding device includes a storage section for storing a dried residue obtained by drying a pomace having grape seeds and skins to a moisture content of 14% or less , a rotating shaft provided in the storage section in a vertically upright position, a stirring plate fixed to the rotating shaft, and a drive controller for adjusting the rotation speed of the stirring plate, and the grinding device rotates the stirring plate to grind the dried residue to grind the skins , and the temperature of the dried residue at the start of grinding is at most 30°C ;
and a separation step of separating the seeds and the crushed pericarp using a net having mesh sizes smaller than the diameter of the seeds after the crushing step .
The stirring plate is
A method for separating grape seeds and skins, comprising either an agitator blade whose two plate surfaces intersect with the vertical direction, or a rotating plate formed in a circular shape with its circular center fixed to the rotating shaft and with unevenness formed on its upper surface that intersects perpendicularly with the vertical direction . The grape seed skin separation method according to claim 1 , wherein the stirring blade has a center in a longitudinal direction fixed to the rotating shaft. 3. The grape seed skin separation method according to claim 1 or 2, wherein the stirring blade has a blade formed along the longitudinal direction and rotates in the direction in which the blade faces. The grape seed pericarp separation method according to any one of claims 1 to 3, wherein the stirring device has a pair of the stirring blades that cross at the center in the longitudinal direction when viewed from above. The grape seed skin separation method according to claim 1 , wherein the stirring device equipped with the rotating plate rotates the rotating plate and collides the dried residue on the rotating plate against the inner surface of the side wall of the storage section. A drying step of drying the juice residue while heating it to a moisture content of 14% or less ;
The drying process further includes a temperature reducing process for reducing the temperature of the dried residue obtained by the drying process to 30° C. or lower .
The grape seed skin separation method according to any one of claims 1 to 5, wherein the dried residue cooled in the temperature-lowering step is subjected to the crushing step . The method for separating grape seed skins according to claim 1 , wherein the crushing step comprises intermittently cooling the dried residue. The method for separating grape seed skins according to claim 1 , wherein the crushing step comprises intermittently stirring the dried residue.