JP2006197809A - Method for preserving food residue, and food residue preserved by the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for preserving a food residue considerably simplifying facilities necessary for a treating process for making food residue such as bean curd refuse preservable for a long time, and remarkably reducing energy necessary for the process: and to provide a food residue preserved by the method. <P>SOLUTION: The method for preserving a food residue comprises charging bean curd refuse 1 comprising a food residue just after being discharged in a food production process into a storage vinyl bag 2; spraying mixture 3 of baker's yeast and glucose to the upper surface of the bean curd refuse 1 in the storage vinyl bag 2 so as to cover the whole of the bean curd refuse; tying the opening of the storage vinyl bag 2 to seal the bag 2. By the method, the bean curd refuse 1 can be sprayed without being cooled and has no need of temperature control after spray because the baker's yeast is applicable to a wide range of temperature allowing ethanol fermentation and has high heat resistance. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a preservation method for long-term preservation of food residues (for example, okara) discharged as a by-product after food production, and a food residue preserved by the preservation method. In particular, the present invention relates to a measure that enables long-term storage of food residues while simplifying equipment for storage processing and reducing energy costs.

  Conventionally, Okara (tofu cake) is listed as a typical food residue used as livestock feed. About 1.4 kg (about 80% moisture) of this okara is discharged per 1 kg of soybeans. For example, 250 tons of okara per day is discharged from a tofu producer in Osaka Prefecture. In addition, since this Okara has high moisture and high nutritional value, if it is left as it is, it will decay quickly, and if it decays in large quantities, the subsequent disposal (incineration, etc.) will be complicated. There is a problem that it becomes. In addition, there is a problem that in the disposal process, the rot is promoted at the transportation stage and a bad odor is emitted. Furthermore, there is a concern that dioxins are generated when incinerated due to the high moisture content.

  In view of this problem, until now, for example, as disclosed in Patent Document 1 below, lactic acid bacteria are introduced into okara and fermented to suppress propagation of miscellaneous bacteria and enable long-term storage. It has been broken. Thus, as a specific treatment process for preventing corruption due to the introduction of lactic acid bacteria, first, the okara discharged from the tofu producer is transported to a treatment facility. In a state where it is lowered from about% to about 50%, lactic acid bacteria are introduced into okara and fermented, and this fermentation prevents the propagation of various bacteria. The reason why the moisture of okara is lowered from about 80% to about 50% as described above is that butyric acid bacteria are more dominant than lactic acid bacteria in a high moisture state, and there is concern about the progress of decay. In other words, the moisture of okara is lowered to about 50% to create an environmental state in which lactic acid bacteria are superior to butyric acid bacteria, and the growth of butyric acid bacteria can be suppressed by the enzymes of lactic acid bacteria.

  However, in the above-described processing method, spoilage may start at the stage of transporting okara from the tofu producer to the processing facility, and even if lactic acid bacteria are added and fermented thereafter, a sufficient effect can be obtained. There was a possibility that corruption could not be suppressed. Also, a special device for lowering the moisture of Okara from about 80% to about 50%, such as a drying device or a mixing device for dry matter (wheat skin waste, hay, etc.) is required, and this device is driven. Energy is also required.

In view of these problems, the inventors of the present invention tried to preserve okara for a long period of time using ethanol fermentation by wine yeast. In other words, wine yeast and sugars such as glucose are added to okara, and this wine yeast performs ethanol fermentation using the sugar as a substrate to generate alcohol, and this alcohol can prevent the propagation of germs (septic bacteria). Is. As a result, the storage stability of okara can be improved without requiring conventional moisture adjustment.
JP-A-9-322729

However, there is still a problem to be solved even in the long-term preservation method of okara using ethanol fermentation by the wine yeast described above.
(1) First, in wine yeast, it is raised that the range of the environmental temperature in which ethanol fermentation is possible is narrow. Specifically, since wine yeast performs ethanol fermentation only in an environment of about 15 ° C., equipment for maintaining this environment is necessary. For example, Okara must be stored in a temperature-controlled warehouse. This necessitates an apparatus for constructing this type of equipment and maintaining the temperature, and energy for driving the apparatus.
(2) Moreover, since wine yeast has low heat resistance, it cannot be added unless the temperature of the okara is sufficiently lowered. Specifically, since the temperature immediately after discharge of okara discharged in the tofu production process is a high temperature of about 90 ° C., after cooling this to the temperature at which ethanol fermentation is possible (about 15 ° C.) It is necessary to add wine yeast. Therefore, a special cooling device for cooling the okara is required and energy for driving this device is also required. Moreover, it is necessary to perform a cooling operation in an aseptic environment so that germs do not enter during the cooling process of the okara, and the environmental management is also complicated.
(3) Wine yeast is expensive (for example, about 6000 yen per 500 g), and when used to store a large amount of discharged okara as described above for a long period of time, the price of livestock feed increases, which is practical. Lack.

  These problems occur not only when okara is stored for a long period of time, but also when other food residues (beer lees, bean paste, etc.) are stored for a long period of time.

  The present invention has been made in view of the above points, and the object of the present invention is to greatly simplify and necessitate equipment necessary for a processing step for enabling food residues such as okara to be stored for a long period of time. Another object of the present invention is to provide a food residue storage method that can greatly reduce the energy required and a food residue stored by the storage method.

-Summary of invention-
In order to achieve the above object, the solution means of the present invention uses baker's yeast as a yeast for ethanol fermentation using a saccharide as a substrate. Bakery yeast is superior to wine yeast in that it has a wide environmental temperature range for ethanol fermentation and has high heat resistance, and is also cheaper and cheaper than wine yeast. Is excellent.

-Solution-
Specifically, the present invention is directed to a storage method for storing food residues for a long period of time. And as this preservation | save method, the food residue immediately after discharged | emitted from the food manufacturing process is thrown into the storage container, and the food stored in the said storage container after the completion of this charging process The surface exposed to the outside air in the residue is provided with a spraying step of spraying baker's yeast and sugar so as to cover the entire surface, and then a sealing step of sealing the storage container.

  By this specific matter, for example, when this solution is applied as a method for preserving okara, the high-temperature, high-moisture okara discharged from the tofu producer is directly used as a storage container, for example, a storage vinyl bag (with a storage container). (It may be) During this operation, the okara is cooled to about 45 ° C. by natural heat dissipation. Thereafter, baker's yeast and sugars (such as glucose) are sprayed over the entire top surface of the okara (surface exposed to the outside air) from the opening of the storage vinyl bag. That is, Okara is in a state of being blocked from the outside air by a layer made of baker's yeast and sugar. Thereafter, the opening of the storage vinyl bag is closed to seal the inside of the bag (in the case of a storage container, the lid is closed to close the inside of the container). When okara is stored in this manner, baker's yeast performs ethanol fermentation using saccharides as a substrate to produce alcohol, and this alcohol prevents the growth of miscellaneous bacteria. In this way, it is possible to improve the storage quality of okara without requiring temperature adjustment or moisture adjustment. Specifically, it can be stored for several months to 2 years. In addition, baker's yeast has a wider temperature range of environmental temperature that enables ethanol fermentation than wine yeast, and ethanol fermentation can be performed in a temperature environment of about 5 ° C to 35 ° C (so-called normal temperature). Therefore, special equipment for maintaining the environmental temperature for ethanol fermentation is not necessary. Further, since this facility is unnecessary, energy for maintaining the environmental temperature is not necessary. In addition, baker's yeast has higher heat resistance than wine yeast and does not die even when sprayed on okara at a temperature reduced by the natural heat dissipation (about 45 ° C.). For this reason, a special cooling device for sufficiently reducing the temperature of the okara before spraying baker's yeast is unnecessary. Further, since this cooling device is unnecessary, energy for driving the cooling device is also unnecessary. Furthermore, baker's yeast is cheaper than wine yeast (for example, about 1000 yen per 500 g), and can store okara for a long time at low cost (about 1/6 of wine yeast). The price will not rise. In addition, according to this preservation | save method, aromatic ester is produced | generated with the ethanol fermentation by the said baker's yeast. For this reason, when the preserved Okara is given to livestock, the palatability is improved and the appetite of the livestock is increased, so that an added value (good quality silage feed) as livestock feed can be obtained. In addition, the production of this aromatic ester is not only due to the ethanol fermentation by baker's yeast described above, but also by the fermentation of lactic acid bacteria present in the storage container in contact with the alcohol produced by the ethanol fermentation. Is also done.

  As described above, when the storage container is made of a non-breathable bag, and in the spraying process, bread yeast and sugar are sprayed so as to cover the entire top surface of the food residue contained in the bag. Can easily form a layer of baker's yeast and saccharides for blocking between food residues and the outside air, and the workability is improved. Moreover, if a bag body (for example, a vertically long bag body) in which the area of the upper surface of the stored food residue is reduced, a large amount of food residue can be stored with a small amount of baker's yeast and sugar.

  Moreover, the food residue thrown into the preservation | save container in the said addition process is thrown into a preservation | save container, without passing through the process of temperature adjustment and a water | moisture content adjustment. As described above, baker's yeast can be applied to a food residue having a relatively high temperature that is cooled by natural heat dissipation. Moreover, since the effect of preventing miscellaneous bacteria growth by alcohol is obtained, there is no need for moisture adjustment. In other words, butyric acid bacteria do not grow even in a high moisture state. Therefore, food residues can be stored for a long time without requiring a special device such as a cooling device or a drying device.

  Prior to the spraying step, the mixing step of mixing baker's yeast and sugar is performed, and the baker's yeast and sugar mixed in this mixing step are subjected to the entire surface where food residues are exposed to the outside air in the spraying step. It is sprayed to cover. Thereby, uniform distribution of baker's yeast and saccharides in a layer that blocks food residues from the outside air can be achieved, and ethanol fermentation using baker's yeast can be performed efficiently.

  In the spraying step, baker's yeast and sugar are sprayed so as to cover the entire top surface of the food residue in a powder state. That is, baker's yeast and sugars are in a dry state before spraying, and baker's yeast does not start ethanol fermentation in this state. And these baker's yeast and saccharides are spread | dispersed on a food residue, and baker's yeast starts ethanol fermentation by baker's yeast and saccharide | sugar absorbing the water | moisture content contained in this food residue. In particular, when applied to high moisture food residues such as okara, ethanol fermentation starts immediately after spraying. Thus, by making baker's yeast and saccharides in a powder state, ethanol fermentation can be prevented from being started before spraying, and ethanol fermentation can be started at an appropriate timing.

  Specifically, monosaccharides or disaccharides are listed as sugars to be sprayed on food residues together with baker's yeast in order to perform the ethanol fermentation. For example, as monosaccharides, glucose, fructose, galactose, mannose and the like are listed, and as disaccharides, maltose, sucrose, lactose, cellobiose and the like are listed.

  The storage container is provided with a valve body having a one-valve function that prohibits the passage of gas and liquid from the outside of the container to the inside and allows only the passage of gas from the inside of the container to the outside. This is for discharging carbon dioxide generated along with the ethanol fermentation to the outside of the storage container while preventing invasion of germs from the outside into the container. In particular, when a storage vinyl bag is used as a storage container, there is a risk that the bag internal pressure will increase with the generation of carbon dioxide and it may burst, so it is important to discharge this carbon dioxide.

  Specific examples of the food residue that can be used in the present invention include okara, beer lees, and red bean paste. Since both of these have high moisture and high nutritional value, and there is a possibility that the spoilage proceeds at an early stage, the preservation method according to the present invention is particularly effective. In addition, this invention is applicable also to food residues other than these.

  In addition, the food residue preserve | saved by the food residue preservation | save method as described in any one of the solution means mentioned above is also the category of the technical idea of this invention. That is, it is a food residue containing alcohol produced by ethanol fermentation of baker's yeast that is sprayed with baker's yeast and sugars.

  In the present invention, as a storage method for storing food residues for a long period of time, the temperature range of the environmental temperature at which ethanol fermentation is possible is wider than that of wine yeast, and baker's yeast having higher heat resistance than that of wine yeast is used. The storage container is sealed by spraying baker's yeast and sugar so as to cover the residue. For this reason, the special installation for maintaining the environmental temperature which performs ethanol fermentation, and the special cooling device for fully reducing the temperature of a food residue before spraying of baker's yeast are unnecessary. Moreover, even if the moisture content of the food residue is high, the growth of spoilage bacteria is prevented by the alcohol produced by ethanol fermentation. For this reason, temperature adjustment and moisture adjustment are not required, and food residues can be stored for a long period of time while simplifying equipment for storage processing and reducing energy costs.

  In addition, baker's yeast is cheaper than wine yeast, and it is possible to store okara for a long time at a low cost, so that the price of livestock feed is not increased.

  Furthermore, since aromatic esters are produced with ethanol fermentation by the above baker's yeast, the palatability when stored food residues (ocara) are given to livestock is improved, and the added value as feed for livestock is obtained. It is possible to improve the recyclability of food residues. In addition, it is possible to eliminate the additives that have been necessary in the past for producing high-quality silage feed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. This invention demonstrates the case where okara is used as a food residue and this okara is stored in a state of being packed in a storage vinyl bag.

  First, as shown in FIG. 1 (a), a high temperature (about 90 ° C.) and high moisture (about 80% moisture) of okara (food residue) 1 discharged from a tofu producer is stored as it is as a storage container. The plastic bag 2 is charged and stored (the charging step referred to in the present invention). As the storage vinyl bag 2 used here, for example, a bag for 20 kg is used. The size and shape of the storage vinyl bag 2 are not particularly limited, but those having a vertically long shape (those having a depth depth larger than the opening size at the upper end) are preferable. This is because the entire top surface of the okara 1 can be covered with a small amount of baker's yeast and sugar in the spraying step described later, and a large amount of okara 1 can be stored. In addition, this okara charging operation may be carried out automatically or continuously by carrying the okara 1 on a conveyor and placing a storage vinyl bag 2 on the downstream end of the conveyor, or by an operator's manual operation. May be.

  During this series of charging operations, the okara 1 is cooled by natural heat dissipation. For example, it is cooled to about 45 ° C. when it is put into the storage vinyl bag 2. Then, when a predetermined amount of the okara 1 is put into the storage vinyl bag 2, the charging operation is finished, and then the spraying process is started. In this spraying step, as shown in FIG. 1 (b), the mixture 3 of baker's yeast and glucose is sprayed from the upper opening of the storage vinyl bag 2 over the entire top surface of the okara 1 (the surface exposed to the outside air). become. These baker's yeast and glucose are premixed in a powder state. That is, in this state, baker's yeast and glucose are in a dry state so that ethanol fermentation of baker's yeast is not started. The baker's yeast and glucose are mixed in advance in a predetermined ratio (mixing step). Thereby, uniform distribution of baker's yeast and glucose can be achieved. By spraying the mixture 3, the okara 1 is blocked from the outside air by a layer made of baker's yeast and sugar (see an enlarged view of FIG. 1B). For the operation of spraying the mixture 3 of baker's yeast and glucose, the mixture 3 is conveyed by a conveyor, and a storage vinyl bag 2 is disposed at the downstream end of the conveyor, so that the automatic continuous spraying can be performed. It may be sprayed manually.

  When spraying the mixture 3 of baker's yeast and glucose, the mixture 3 and the okara 1 may be mixed and stirred, and the mixture 3 may be sprayed over the entire upper surface of the okara 1. However, since only the mixture 3 sprayed on the upper surface of the okara 1 can sufficiently perform ethanol fermentation, which will be described later, and it is possible to prevent the propagation of various bacteria, it is not always necessary to perform mixing and stirring.

  When the mixture 3 of baker's yeast and glucose is sprayed over the entire top surface of the okara 1 in this way, the baker's yeast and glucose absorb the water contained in the okara 1, thereby causing the baker's yeast to undergo ethanol fermentation. Start. That is, by making baker's yeast and glucose in a powdered state, ethanol fermentation can be prevented from starting before spraying, and ethanol fermentation can be started at an appropriate timing.

  Thereafter, as shown in FIG. 1 (c), the opening of the storage vinyl bag 2 is closed and tied with a string 4 or the like, and the inside of the bag is hermetically sealed so as to prevent the introduction of outside air (the sealing step referred to in the present invention). ).

  In addition, on the surface of the storage vinyl bag 2 that faces the upper space in the bag (the space not filled with okara), the passage of gas and liquid from the outside of the bag to the inside is prohibited, A seal member (a member having a one-way permeable membrane) 5 is attached as a valve body having a one-valve function that allows only passage of gas from the outside to the outside. Specifically, a small-diameter opening is formed in a part of the storage vinyl bag 2, and a one-way permeable membrane is attached so as to close the opening. Thereby, the seal structure which permits only passage of gas from the bag inside toward the outside is obtained. This configuration is for discharging carbon dioxide generated along with ethanol fermentation to the outside of the bag while preventing invasion of germs from the outside into the bag. This discharge of carbon dioxide can prevent the storage vinyl bag 2 from bursting.

  This completes the operation for saving the okara. If the okara is stored in this manner, baker's yeast produces ethanol by using glucose, which is a saccharide, as a substrate to produce alcohol, and this alcohol prevents the propagation of miscellaneous bacteria. In this way, it is possible to improve the storage quality of okara without requiring temperature adjustment or moisture adjustment.

  In addition, the aromatic ester is produced | generated in the inside of the preservation | save vinyl bag 2 with the ethanol fermentation by the said baker's yeast.

  The inventors of the present invention stored the okara in a plurality of preserving vinyl bags by this technique, and conducted an experiment on the period until the occurrence of mold on the okara. As a result, no fungi were observed in all the vinyl bags for storage even after 3 months. In addition, about half of the products did not show mold even after 2 years.

  As described above, in this embodiment, long-term storage of okara is enabled by using baker's yeast as yeast for performing ethanol fermentation using saccharides as a substrate. Compared with wine yeast, this baker's yeast has a wider temperature range of environmental temperature at which ethanol fermentation is possible, and ethanol fermentation can be performed in a temperature environment of about 5 ° C. to 35 ° C. (so-called normal temperature). Therefore, special equipment for maintaining the environmental temperature for performing ethanol fermentation is unnecessary. Further, since this facility is unnecessary, energy for maintaining the environmental temperature is not necessary. In addition, baker's yeast has higher heat resistance than wine yeast and does not die even when sprayed on okara at a temperature reduced by the natural heat dissipation (about 45 ° C.). For this reason, a special cooling device for sufficiently reducing the temperature of the okara before spraying baker's yeast is unnecessary. Further, since this cooling device is unnecessary, energy for driving the cooling device is also unnecessary. Furthermore, baker's yeast is cheaper than wine yeast, and it is possible to store okara for a long period of time at a low cost, without causing an increase in the price of livestock feed.

  In addition, as described above, since aromatic esters are generated with ethanol fermentation by baker's yeast, when stored okara is given to livestock, the palatability is improved and the added value as livestock feed is obtained. be able to. In particular, in the case of Okara, the demand for tofu increases rapidly in summer and winter, resulting in a large amount of by-product and oversupply, while in the spring and autumn, the amount of by-product decreases and there is a shortage of livestock feed. There was a current situation. According to this embodiment, since it is possible to store okara for a long period of time for several months or more, it becomes possible to consume the surplus of okara produced as a by-product in summer in autumn, and for high quality livestock throughout the year. Feed can be stably supplied.

-Other examples-
In the embodiment described above, the case where okara is used as a food residue and the okara is stored in a state of being packed in a storage vinyl bag has been described. The present invention is not limited to this, and can also be applied to beer lees, bean koji, and other food residues as food residues. A storage container may be used as a container for storing food residues.

  In addition, monosaccharides or disaccharides can be used as saccharides to be applied to food residues together with baker's yeast. For example, as monosaccharides, fructose, galactose, mannose and the like are listed in addition to the above glucose, and as disaccharides, maltose, sucrose, lactose, cellobiose and the like are listed.

It is a figure which shows a series of work of the food residue preservation | save method.

Explanation of symbols

1 Okara (food residue)
2 Vinyl bag for storage (container for storage)
3 Mixture of baker's yeast and glucose (sugar) 5 Seal member (valve)

Claims (9)

A storage method for long-term storage of food residues,
An input process for storing the food residue immediately after being discharged from the food manufacturing process in a storage container;
After the completion of this charging step, a spraying step of spraying baker's yeast and sugar so as to cover the entire surface exposed to the outside air in the food residue stored in the storage container,
Then, the preservation | save process of sealing the said storage container is provided, The preservation | save method of the food residue characterized by the above-mentioned. In the preservation method of the food residue of Claim 1,
The storage container is a non-breathable bag,
In the spraying process, the bread yeast and sugar are sprayed so as to cover the entire top surface of the food residue contained in the bag,
In the sealing process, the opening of the bag body is tied to seal the bag body, and the method for preserving food residues is characterized. In the preservation method of the food residue of Claim 1 or 2,
A method for preserving a food residue, characterized in that the food residue introduced into the storage container in the input step is input into the storage container without going through the temperature adjustment and moisture adjustment steps. In the preservation method of the food residue of Claim 1, 2, or 3,
Prior to the spraying process, a mixing process is performed in which baker's yeast and saccharides are mixed together. A method for preserving food residues, characterized by being sprayed over the entire surface. In the preservation method of the food residue according to any one of claims 1 to 4,
A method for preserving a food residue, characterized in that, in the spraying step, baker's yeast and sugar are sprayed so as to cover the entire top surface of the food residue in a powder state. In the preservation method of the food residue according to any one of claims 1 to 5,
The method for preserving food residues, wherein the saccharide is a monosaccharide or a disaccharide. In the preservation method of the food residue according to any one of claims 1 to 6,
The storage container is provided with a valve body having a one-way valve function that prohibits the passage of gas and liquid from the outside of the container to the inside and allows only the passage of gas from the inside of the container to the outside. To save food residue. In the preservation method of the food residue according to any one of claims 1 to 7,
The method for preserving a food residue, wherein the food residue is okara, beer lees, or bean paste.   A food residue preserved by the food residue preservation method according to any one of claims 1 to 8, wherein baker's yeast and sugars are sprayed, and the alcohol produced by ethanol fermentation of the baker's yeast A food residue characterized by containing.

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