JP5038687B2 - Method for producing soybean oligosaccharide liquid - Google Patents

Description

  The present invention relates to a method for producing an oligosaccharide liquid, and in particular, without removing the peel from peeled whole soybeans, breaking the whole soybeans, or crushing the whole soybeans, the oligosaccharide directly from the peeled whole soybeans. The present invention relates to a method for producing soybean oligosaccharide that can effectively use the residual soybean from which sugar is extracted and oligosaccharide is extracted as feed and fertilizer, and thus does not require disposal of the residual soybean, and enables reduction of environmental burden.

  An oligosaccharide is a dehydrating combination of 2 to 10 monosaccharides, and is another term for oligosaccharides. Certain oligosaccharides are difficult to be decomposed by human digestive enzymes, so they reach the large intestine without being absorbed in the middle, become nutrients for bifidobacteria, which are useful bacteria in the large intestine, and proliferate the bifidobacteria, It has the property that it is difficult to be degraded by bad bacteria in the large intestine such as C. perfringens or E. coli. Oligosaccharides that are selective for the ease of digestion and degradation are used as health-oriented foods to improve constipation and hyperlipidemia, prevent aging, and prevent obesity and arteriosclerosis. Yes.

  Soybean oligosaccharide is a general term for various oligosaccharides (oligosaccharides) contained in soybean, and is one of the above-mentioned oligosaccharides that are selective in terms of ease of digestion and degradation, and has a sweetness compared to sucrose (sugar). It is weak and gives a refreshing and refreshing sweetness. The soybean oligosaccharide having such a property is particularly useful for the above-mentioned health-oriented food.

Conventionally, as a method for producing soybean oligosaccharide, there is a method in which water is added to okara produced as an unnecessary residue in the production process of tofu and the oligosaccharide component is extracted from various soybean components eluted in water. Are known. There is also known an oligosaccharide production method in which ground soybeans are used in place of okara, oligosaccharide components are eluted from ground soybeans in water, and oligosaccharide components eluted in water are separated. Furthermore, the seed coat of the soybean is removed, the soybean from which the seed coat has been removed is divided into about 2 to 4, and the cracked soybean of half to four is soaked in warm water, and the oligosaccharide is eluted in the warm water. A method described in Japanese Patent Application Laid-Open No. 2004-51493 (Patent Document 1) for producing a soy oligosaccharide solution by concentrating hot water from which water is eluted is known. As another method, when squeezing whole soybeans and squeezing soybean oil, defatted defatted soybeans are produced as a residue of squeezed oil. Extraction methods are also known.
JP 2004-51493 A

  In the above-described conventional method for producing soybean oligosaccharides, crushed soybeans, cracked soybeans, or defatted soybeans become unnecessary residues and are discarded after soybean oligosaccharides are extracted. In particular, the residue obtained by extracting oligosaccharides from okara or pulverized soybean has fine particles, becomes sludge-like, and costs considerably to treat as waste, and places a heavy burden on the environment for disposal. . Further, since the seed coat is also removed from the residue which is cracked soybean from which the oligosaccharide has been extracted, it is gradually refined in the oligosaccharide extraction process, making it difficult to use as a feed or fertilizer. In addition, since the defatted soybean has its seed coat destroyed when it is shredded in the oil extraction process, it is gradually refined in the oligosaccharide extraction process and dispersed in hot water. Therefore, the residue remaining in the oligosaccharide extraction process of defatted soybean is still in a sludge shape, and the cost for processing as waste is considerably high, which places a great burden on the environment for disposal.

  In addition, conventional methods for extracting soybean oligosaccharides from okara, ground soybeans, split soybeans or defatted soybeans extract oligosaccharides from soybeans with seed coats removed or seed coats destroyed, so soybean oligosaccharides are extracted. In the process of extracting sugar, protein and lipid components are almost extracted from soybean together with oligosaccharide, and there are few nutrient components remaining in the residue. Therefore, also in terms of nutritional value, the residue produced by the conventional oligosaccharide liquid production method is difficult to use as feed or fertilizer and must be disposed of as waste. However, disposal of soybean residues as waste requires a considerable amount of money, and the disposal process places a great burden on the environment.

  Therefore, the object of the present invention is to extract the oligosaccharide directly from the peeled whole soybean without removing the seed coat from the whole peeled soybean, breaking the whole soybean, or crushing the whole soybean. Residual soybeans extracted with oligosaccharides can be used effectively as feed and fertilizer, and as a result, there is no special cost for disposal of residual soybeans, and soy oligosaccharide liquid production method that enables reduction of environmental burden. On offer.

  In order to solve the above-mentioned problems, the present invention provides the following means.

(1) A hot water extraction step of extracting a saccharide from the whole soybean into the water by boiling the whole soybean in water to produce a saccharide liquid that is a liquid containing the sugar;
By applying the process to the carbohydrate solution, viewed contains a carbohydrate solution treatment step of generating a soybean oligosaccharide solution containing soybean oligosaccharide at a concentration higher than in the sugar interstitial fluid before the treatment,
Before Symbol sugar quality liquid treatment step,
A residual soybean removal step of removing the residual soybean from which the sugar has been extracted in the hot water extraction step from the carbohydrate liquid;
A first concentration step of concentrating the carbohydrate liquid from which the residual soybean has been removed in the residual soybean removal step to produce a concentrated carbohydrate solution;
Autoclaving step of autoclaving the concentrated carbohydrate solution;
Filtering the first concentrated carbohydrate solution sterilized in the autoclave step with a filter to produce a filtered concentrated carbohydrate solution;
Refrigerated storage step of storing the filtered concentrated saccharide liquid in a container at a low temperature of 0 ° C. or more and 5 ° C. or less for a period of 1 day or more, and precipitating water-soluble dietary fiber in the container;
A decantation step in which the supernatant of the filtered concentrated saccharide liquid in which the water-soluble dietary fiber is precipitated in the refrigerated storage step is separated from the precipitate that has precipitated in the container;
A second concentration step of concentrating the supernatant taken out in the decantation step to produce a soybean oligosaccharide solution;
A method for producing a soybean oligosaccharide liquid , comprising :

  ADVANTAGE OF THE INVENTION According to this invention, the special expense for the disposal process of residual soybean is not required, and the soybean oligosaccharide manufacturing method which makes it possible to reduce environmental impact can be provided.

  Next, the present invention will be described in more detail with reference to embodiments of the present invention. FIG. 1 is a process diagram showing a soybean oligosaccharide production method according to the present embodiment. This soybean oligosaccharide production method is composed of 9 steps from the washing / water immersion step S1 to the concentration step S9 in FIG.

  In the water washing / water soaking step S1, the whole soybeans with seed coats are washed with water to wash away the dirt adhering to the seed coats, and the washed whole soybeans are put into a container, and water of 5 times weight ratio is put into the container. In addition, the whole soybeans are soaked in water at room temperature for 12 hours, and the whole soybeans are swollen until they swell about 4 times by weight. Depending on the water immersion temperature, the degree of swelling of whole soybeans differs, so the water immersion time is adjusted according to the temperature, and the whole soybeans are swollen until they swell about 4 times in weight ratio.

  In the hot water extraction step S2, the whole soybeans swollen in the water washing / water soaking step S1 are placed in a pan together with 5 times the weight of water and boiled at atmospheric pressure for about 235 minutes to heat the sugar containing oligosaccharides. Extract with water. The present embodiment is characterized in that the hot water extraction step S2 is performed on the whole soybeans with seed coats. Carbohydrates such as oligosaccharides and water-soluble dietary fiber dissolve well in hot water by extracting with hot water while still using whole soybeans, but the protein and lipids of soybeans are hindered by the seed coat and dissolved in hot water Is slight. And the soybean which became residue by extracting saccharides, such as an oligosaccharide, and water-soluble dietary fiber is a whole soybean with a seed coat | cover. From this, the residue can be easily removed by the subsequent residue soybean removal step S3, so that no special expense is required for the disposal treatment of the residue soybean, and the residue hardly puts a burden on the environment. Moreover, since most of the protein and lipid remain in the residual soybean, the residual soybean is useful as a feed or fertilizer, and from this point of view, there is almost no processing cost for the residual soybean.

  In the pressure kettle at the end of the hot water extraction step S2, water containing saccharides such as oligosaccharides and water-soluble dietary fiber and soy extracted from the sugar and water-soluble dietary fiber (residual soybean) are mixed. To do. In the residual soybean removal step S3, a mixture of the carbohydrates such as oligosaccharides and water containing water-soluble dietary fiber and the residual soybeans is transferred to a jar, and the carbohydrates such as oligosaccharides and the like excluding residual soybeans and Water-containing dietary fiber-containing water is obtained.

  In the concentration step S4, saccharides such as oligosaccharides and water-containing dietary fiber-containing water obtained in the residual soybean removal step S3 are concentrated five times with a vacuum kettle (concentration until the liquid volume is reduced to 1/5). .

  In the autoclaving step S5, the concentrated liquid obtained in the concentrating step S4 is put into a high-pressure kettle, the temperature inside the high-pressure kettle is set to 120 ° C. (pressure in the high-pressure kettle: about 2 atm), heated under pressure for 7 minutes, and concentrated. Sterilize the solution.

  In the filtration step S6, the sterilized concentrated solution obtained in the autoclave step S5 is filtered through a filter having a nominal diameter of 0.2 microns, and is peeled off from the surface of the whole soybeans in steps S1 to S3, or the liquid is used in the processes of steps S4 and S5. Removes solids of 0.2 microns or more formed by agglomeration.

  In the refrigerated storage step S7, the concentrate obtained by filtration in the filtration step S6 is put in a container, cooled to a temperature of 2 ± 0.5 ° C., stored for about 2 days, and heavy components in the concentrate are precipitated. The precipitated component is rich in water-soluble dietary fiber. The water-soluble dietary fiber component precipitates and gels while being stored at a low temperature to form a jelly. Oligosaccharides are oligosaccharides having a low molecular weight, starch and water-soluble dietary fiber are polysaccharides, and molecular weight is large and heavy, so that oligosaccharides gradually float during water storage and water-soluble dietary fibers gradually precipitate. Therefore, in the refrigerated storage step S7, the oligosaccharide and the water-soluble dietary fiber are separated into a supernatant component and a precipitation component in the container, the oligosaccharide is contained in the supernatant, and the dietary fiber is contained in the precipitate. Refrigerated storage is also meaningful in terms of preventing the growth of germs in the concentrate.

  In the decantation step S8, the concentrated solution is stored at a low temperature in the refrigerated storage step S7, and when the heavy components of the concentrated solution are in a precipitated state at the bottom of the container, the container is gently tilted and only the supernatant liquid is transferred to another container. Pour into. Note that decantation is a term in the chemical field, and refers to an operation of sinking a precipitate toward the bottom of the container and then pouring only the supernatant liquid by gently tilting the container. The component precipitated in the concentrated solution refrigerated in step S7 contains a large amount of water-soluble dietary fiber as described above, and the water-soluble dietary fiber component is in a jelly shape during refrigerated storage. Then, only the liquid supernatant can be easily taken out, and the precipitate does not flow out together with the supernatant. In the present embodiment, the oligosaccharide can be separated and taken out from the water-soluble dietary fiber with high yield and low cost by the refrigerated storage step S7 and the decantation step S8.

  In the concentration step S9, the supernatant obtained in the decantation S8 is concentrated about 5 times with a vacuum kettle to obtain the soybean oligosaccharide solution of this embodiment. When the concentrated solution obtained in the concentration step S9 was analyzed, the concentrated solution contained 12.5% oligosaccharide components and had a sugar content of 75%. The breakdown of the oligosaccharide components was raffinose 2.7% and stachyose 9.8%.

  Although the present invention has been described in detail with the embodiment for ease of understanding, the present invention is of course not limited to this embodiment. For example, the present invention can be implemented even if the water immersion step of step S1 is omitted. Even if it shifts to hot water extraction process S2 immediately after a water washing process without omitting water immersion and swelling whole soybeans, an oligosaccharide component can be extracted in hot water in hot water extraction process S2. Moreover, in the said embodiment, although the temperature in each process, time, a density | concentration, the nominal diameter of a filter, etc. were shown by the specific value, the method of this invention is not limited to these values. For example, in the above embodiment, in the hot water extraction step S2, oligosaccharide was first extracted by boiling at 235 minutes under atmospheric pressure, but the boiling time may be longer or shorter than 235 minutes. The longer the boiling time, the better the oligosaccharide yield. Further, the hot water extraction step S2 may be performed under pressure, not under atmospheric pressure. In order to perform the hot water extraction step S2 under pressure, for example, the swollen soybeans obtained in the water washing / water immersion step S1 are put into a pressure cooker, water at a weight ratio of 5 times is added, and the temperature in the pressure cooker is 105.5 ± 0.5. Perform hot water extraction for about 90 minutes under pressure of ℃. In this hot water extraction for about 90 minutes, oligosaccharides still remain in the residual soybean, so to further increase the yield, after the first hot water extraction under pressure, the contents of the pressure cooker Is separated into oligosaccharide eluate and soybeans using a rice cake, and only the soybeans are put into the pressure cooker again, and the second hot water extraction is performed under the same conditions as the first. The oligosaccharide contained in the whole soybean is mostly extracted by the hot water extraction under the two pressures. In addition, hot water extraction under pressure is given as an example of a pressure at which the temperature in the pressure kettle becomes 105 ° C. However, hot water extraction with this pressure being a higher value is effective in terms of increasing extraction efficiency. However, the higher the pressure, the more protein is eluted in addition to the oligosaccharide, and there is another problem that the purity of the oligosaccharide decreases.

  Moreover, although the autoclave process S5 was the heat treatment for 7 minutes under the pressure of about 2 atmospheres where the pressure kettle temperature becomes 120 ° C., the pressure and the heating time are not limited thereto. However, the heating time of 7 minutes is long enough for sterilization, and if the heating time is too long, the concentrated solution will scorch against the pressure cooker. Moreover, although the nominal diameter of the filter used in filtration process S6 was 0.2 micron, the nominal diameter is not limited to this value. The larger the nominal diameter of the filter, the shorter the time required for filtration. However, the final mouthfeel of the oligosaccharide gradually becomes coarser, and conversely, the smaller the nominal diameter of the filter, the longer the required time for filtration. However, the mouthfeel of the oligosaccharide finally obtained becomes smooth. In the filtration step S6, it is efficient to filter a certain amount of sterilized concentrated solution at a time, but for the convenience of the capacity of the decompression kettle and the pressure kettle in the processing from step S1 to step S6, 1 If the dormitory of the sterilized concentrate obtained by the process from batch S1 to S6 is insufficient for filtration in the filtration step S6, a step of storing the sterilized concentrate refrigerated immediately before the filtration step S6 is provided. In addition to the previous sterilized concentrate that has been stored refrigerated, the sterilized concentrate obtained by the process from step S1 to step S6 for the second time is added to the sterilized concentrate obtained in the next process from step S1 to step S6. The liquid may be filtered. At this time, it is necessary to return the sterilized concentrate that has been refrigerated to room temperature, mix the precipitates such as dietary fiber that have precipitated during storage, and the supernatant, and then mix with the sterilized concentrate that is generated later. It is.

  In the refrigerated storage step S7, the storage is performed at a temperature of 2 ° C. for 2 days. If the temperature is in the range of −1 ° C. to 5 ° C., the water-soluble dietary fiber that is a precipitate can be gelled. In addition, since the growth of various bacteria can be prevented, the present invention can be carried out. The period of the refrigerated storage is 2 days for gelation of the water-soluble dietary fiber, but a longer period, for example, 5 days may be used.

  The round soybean used in the present invention may be either yellow soybean or black soybean. Black soybean contains a kind of anthocyanin, a polyphenol known as an antioxidant, and is said to be preferable for health promotion. However, when the raw material is black soybean, the oligosaccharide solution obtained in step S9 is blackish. It becomes a color and is different from the light yellow transparent oligosaccharide liquid obtained from yellow soybean. Therefore, when black soybean is used as a raw material and a transparent oligosaccharide solution is obtained, a decoloring step using activated carbon may be provided following step S9.

It is process drawing which shows the soybean oligosaccharide manufacturing method which is this Embodiment.

Explanation of symbols

S1 Washing / water soaking process S2 Hot water extraction process S3 Residual soybean removal process S4 Concentration process S5 Autoclave process S6 Filtration process S7 Refrigerated storage S8 Decantation process S9 Concentration process

Claims (1)

A hot water extraction step of extracting a saccharide from the whole soybean into the water by boiling the whole soybean in water to produce a saccharide liquid which is a liquid containing the sugar;
By applying the process to the carbohydrate solution, viewed contains a carbohydrate solution treatment step of generating a soybean oligosaccharide solution containing soybean oligosaccharide at a concentration higher than in the sugar interstitial fluid before the treatment,
The carbohydrate solution treatment step includes
A residual soybean removal step of removing the residual soybean from which the sugar has been extracted in the hot water extraction step from the carbohydrate liquid;
A first concentration step of concentrating the carbohydrate liquid from which the residual soybean has been removed in the residual soybean removal step to produce a concentrated carbohydrate solution;
Autoclaving step of autoclaving the concentrated carbohydrate solution;
Filtering the first concentrated carbohydrate solution sterilized in the autoclave step with a filter to produce a filtered concentrated carbohydrate solution;
Refrigerated storage step of storing the filtered concentrated saccharide liquid in a container at a low temperature of 0 ° C. or more and 5 ° C. or less for a period of 1 day or more, and precipitating water-soluble dietary fiber in the container;
A decantation step in which the supernatant of the filtered concentrated saccharide liquid in which the water-soluble dietary fiber is precipitated in the refrigerated storage step is separated from the precipitate that has precipitated in the container;
A second concentration step of concentrating the supernatant taken out in the decantation step to produce a soybean oligosaccharide solution;
A method for producing a soybean oligosaccharide liquid , comprising :

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