JP2011229441A - Method of producing sweet potato liquid koji - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide sweet potato liquid koji that enhances a sugar hydrolase activity.SOLUTION: There is provided a method of producing the sweet potato liquid koji, that includes a step of culturing a koji mold by using a liquid culture medium including a sweet potato scrap having an sweet potato end piece separated from a raw sweet potato body.

Description

  The present invention relates to a method for producing a cocoon liquid koji, and more particularly, to a method for producing a koji liquid koji with enhanced sugar hydrolase activity.

  In general, shochu shochu is obtained by first fermenting yeast with added yeast while allowing the enzyme to act on the koji, breaking down the starch contained in the koji into sugar (ie, saccharification), and distilling and purifying the fermented product. Manufactured.

  In order to saccharify the starch of koji, a sugar hydrolase such as amylase is necessary. As a source of enzyme, salmon is used. As rice cake, rice bran is usually used. This is because rice bran is easy to manufacture and obtain.

  Salmon may be used as a source of enzyme. The shochu using shochu is called pure shochu (shochu made from 100% shochu). Pure potato shochu has a strong flavor peculiar to koji compared to ordinary koji shochu using rice koji, and is evaluated as a differentiated liquor quality.

  However, it is known that sweet potato has a high water content and is difficult to use as a raw material for cultivation of koji. For example, Patent Document 1 describes a roasted potato cake made by cutting potatoes into predetermined dimensions and roasting them with a reduced water content by roasting.

  On the other hand, in a koji, a solid koji that is directly inoculated with a spore of a filamentous fungus as a culture raw material and a culture medium and other nutrient sources are added to water to prepare a liquid medium. There are liquid rice cakes that are inoculated with cultured mycelia.

  The liquid culture method is easy for culture control and quality control, and is a culture form suitable for efficiently producing koji. However, there are few examples in which liquid koji is actually used as an enzyme supply source for producing alcoholic beverages and the like due to weak enzyme activity and insufficient saccharification.

  Patent Document 2 describes producing a koji liquid koji by culturing koji molds in a liquid medium containing koji with the surface covered with an outer skin as a culture raw material. This method for producing the liquid koji does not require any special pretreatment such as roasting or dessert, and can easily produce the koji liquid koji.

  Further, in Non-Patent Document 1, several monoterpene alcohols contribute to the characteristic odor of shochu shochu, and in order to liberate monoterpene alcohol from glycosides such as β-glucoside present in koji, It is described that it is important to control the β-glucosidase activity of sputum.

  Therefore, there is a need for a soot liquid soot that is more manufacturable in production and exhibits high enzyme activity.

JP 2001-95523 A JP2007-74810A

Ota, Journal of the Brewing Society; 86 (4), 250-254, 1991

  The inventor of the present invention solves the above-described conventional problems, and an object of the present invention is to provide a method for producing a liquid koji having better workability in production and enhanced enzyme activity. .

  The present invention provides a method for producing a koji liquid koji, which includes a step of culturing koji mold using a liquid medium containing a piece of sweet potato having an end portion of the sweet potato separated from a main body of the raw sweet potato.

  In one certain form, 6-60g of the pieces of the said sweet potato are added to the liquid culture medium with respect to 100 ml of culture media.

  In one certain form, the carbon source in the said liquid culture medium consists only of the piece of the said sweet potato.

  In one embodiment, the sweet potato is Koganesengan, Akemurasaki, Kokei No. 14, Shirosatsuma, Shiroyutaka, Joy White, Tanegashima Gold, Benihayato, Tanegashima Roman, Anno Red, Anona Kone, Benisatsuma, Beniotome, Venezusma, Ayamura Saki and Joy Red Is at least one selected from the group consisting of

  In one certain form, the said koji mold is a white koji mold, a black koji mold, or a yellow koji mold.

  In one certain form, the liquid soot obtained has enhanced sugar hydrolase activity.

  In one certain form, the said sugar hydrolase is acid-resistant alpha-amylase, alpha-amylase glucoamylase, and beta-glucosidase at least.

  According to the method of the present invention, an enzyme activity, in particular, a sugar hydrolase activity is enhanced in a soy liquid koji, and a soy liquid koji showing a sufficient saccharification power for producing koji shochu is obtained.

2 is a graph showing the enzyme activity of acid-resistant α-amylase in the liquid soot produced in Example 1 and Comparative Example 1. FIG. It is a graph which shows the enzyme activity of the acid-resistant alpha-amylase of the soot liquid koji manufactured in Example 2 and Comparative Example 2. FIG. It is the schematic diagram which showed the position which extract | collected the culture raw material of Example 3 and Comparative Example 3 with respect to the front view of a cocoon main body. It is a graph which shows the enzyme activity of the acid-resistant alpha-amylase and glucoamylase of the soot liquid rice cake manufactured in Example 3 and Comparative Example 3. FIG. It is a graph which shows the saccharification rate obtained by saccharifying sweet potato powder with the soot liquid koji manufactured in Example 3 and Comparative Example 3. It is a graph which shows the enzyme activity of the acid-resistant alpha-amylase and glucoamylase of the soot liquid koji manufactured in Example 5 and Comparative Example 4. It is a graph which shows the enzyme activity of (alpha) -amylase and glucoamylase of the soot liquid koji manufactured in Example 6 and Comparative Example 5. FIG. It is a graph which shows the enzyme activity of the acid-resistant alpha-amylase and glucoamylase of the soot liquid koji produced in Examples 7 and 8 and Comparative Example 6. It is a graph which shows the enzyme activity of the acid-resistant alpha-amylase and glucoamylase of the soot liquid koji produced in Example 9 and Comparative Example 7. 4 is a graph showing the enzyme activities of acid-resistant α-amylase and glucoamylase of the soot liquid koji produced in Example 10. FIG. It is a graph which shows the enzyme activity of (beta) -glucosidase of the soot liquid koji manufactured in Example 11 and Comparative Example 8. FIG.

Liquid medium The liquid medium used in the method of the present invention is a liquid obtained by dissolving or suspending, in water, nutrients necessary for the growth and proliferation of Aspergillus or culture materials containing the nutrients. Such nutrients include, for example, carbon sources, nitrogen sources, inorganic salts and the like.

  As the carbon source, the end portion of the sweet potato separated from the main body of the raw sweet potato is used. The sweet potato is not particularly limited as long as it is of a kind used for the production of shochu. For example, Koganesengan, Akemurasaki, Kokei No. 14, Shirosatsuma, Shiroyutaka, Joy White, Tanegashima Gold, Benihayato, Tanegashima Roma, Anno Red, Anno Kogane, Benisatsuma, Benio Toma, Beniazuma, Ayamura Saki and Joy Red are used. Among them, preferred sweet potatoes are Koganesengan and Joy White.

  The reason for using raw sweet potato is that it is advantageous in terms of energy efficiency because work efficiency and processing are not required.

  Sweet potatoes are tuberous roots that are partly elongated adventitious roots that store nutrients and enlarge. The shape of the sweet potato is therefore substantially cylindrical, with the end portion being formed by gradually becoming narrower in the longitudinal direction. That is, the end part of the sweet potato is a part where the tuberous root enlargement starts from the elongated adventitious root and a part where the hypertrophy existing on the opposite side along the length direction ends. The vicinity of the end portion of sweet potato is recognized as a fibrous and hard portion, unlike the central portion, which is meaty, and in most cases, it is removed from the main body of sweet potato when used for food or processing.

  The end portion of the sweet potato is separated from the main body of the sweet potato. The boundary between the end and the meat part of sweet potato is difficult to determine exactly, but even if the meat part is included in the carbon source to some extent, it does not adversely affect the growth of gonococci or enzyme productivity, There is also no need to strictly separate the end from the flesh.

  The end portion of the sweet potato may be used as it is, as it has been separated empirically according to the type of sweet potato. For example, a piece of sweet potato having a terminal portion removed from the main body of the sweet potato before being used for food or processing can be used as it is as a carbon source.

  A piece of sweet potato having a sweet potato end is separated before the sweet potato body is peeled, and part of the surface may be covered with an outer skin, and is separated after the sweet potato body is peeled. Alternatively, the surface may not be covered with an outer skin. In addition, when it is not required to use only sweet potato as a raw material for gonococcus, moss, cereals, or these components may be used in combination as a carbon source.

  In the present invention, the carbon source concentration is the concentration of sweet potato as a carbon source in the liquid medium, and is calculated based on the weight of sweet potato added to 100 ml of the liquid medium. That is, when 10 g of sweet potato is added to 100 ml of the liquid medium, the carbon source concentration is 10 w / v%.

  A piece of sweet potato having an end portion of sweet potato is used at a rate of 6 to 60 g added to 100 ml of the medium. That is, it is used in such an amount that the carbon source concentration derived from the piece of sweet potato in the liquid medium is 6 to 60 w / v%, preferably 9 to 40 w / v%, more preferably 15 to 30 w / v%. When the carbon source concentration is less than 6 w / v%, the koji mold does not grow or proliferate sufficiently, and the enzyme activity becomes insufficient. When the carbon source concentration exceeds 60 w / v%, the viscosity of the culture solution becomes high and the culture does not proceed easily. Moreover, enzyme activity decreases due to the influence of carbon catabolite repression.

  The nitrogen source is not particularly limited as long as it is a nitrogen supply source necessary for the growth and growth of Neisseria gonorrhoeae. Examples of organic substances include yeast cells or processed products thereof (for example, yeast cell decomposition products, yeast extracts, etc.), and examples of inorganic substances include nitrates.

  As the nitrate, potassium nitrate, sodium nitrate or the like can be used, and potassium nitrate is particularly preferable. The nitrogen source may be used alone or in combination of two or more organic substances and / or inorganic substances.

  The amount of nitrogen source added is not particularly limited as long as it promotes the growth of Aspergillus, but it is 0.1 to 2% (w / vol), preferably 0.5 to 1.0% (w / Vol). Moreover, the addition amount of nitrate as an inorganic substance is 0.05 to 2.0% (w / vol), preferably 0.1 to 2.0% (w / vol), most preferably 0.2 to 1.5. % (W / vol).

  When the addition amount exceeds the upper limit value and less than the lower limit value, enzyme production is not promoted, which is also not preferable.

Other Nutrition The liquid medium used in the present invention may contain sulfate and phosphate in addition to the carbon source or nitrogen source. Enzyme activity is enhanced by using these inorganic salts in combination.

  For example, calcium sulfate, magnesium sulfate heptahydrate, iron sulfate heptahydrate, ammonium sulfate, etc. can be used as the sulfate. These inorganic salts can be used alone or in combination of two or more.

  The concentration of the above-mentioned inorganic salts in the liquid medium is adjusted to such a level that sugar hydrolase, dietary fiber degrading enzyme, proteolytic enzyme and the like are selectively generated and accumulated in the koji mold culture. . For example, in the case of phosphate, it is 0.05 to 1.0% (w / vol), preferably 0.1 to 0.8% (w / vol).

  To the liquid medium, organic substances other than the aforementioned nitrogen source and inorganic salts, inorganic salts, and the like can be appropriately added as nutrient sources. These additives are not particularly limited as long as they are generally used for culturing koji molds, but organic substances such as wheat koji, corn steep liquor, soybean koji, defatted soybeans, etc., and inorganic salts such as ammonium salt and potassium Water-soluble compounds such as salts, calcium salts and magnesium salts can be mentioned, and two or more kinds of organic substances and / or inorganic salts may be used simultaneously.

  These addition amounts are not particularly limited as long as they promote the growth of Neisseria gonorrhoeae, but are about 0.1 to 5% (w / vol) as organic substances and 0.1 to 1% (w / vol.) As inorganic salts. It is preferable to add about vol.

  When these nutrient sources are added in excess of the upper limit value, the growth of koji mold is inhibited, which is not preferable. Moreover, when the addition amount is less than the lower limit, enzyme production is not promoted, which is also not preferable.

  The liquid medium of Aspergillus obtained by mixing the above-mentioned culture raw material and nitrogen source with water may be sterilized as necessary, and the treatment method is not particularly limited. As an example, a high-temperature and high-pressure sterilization method can be mentioned, which may be performed at 121 ° C. for 15 minutes.

Manufacture of liquid koji After cooling the sterilized liquid medium to the culture temperature, the koji mold is inoculated into the liquid medium. The form of the koji mold inoculated into the medium is arbitrary, and spores or hyphae can be used.

There is no particular limitation on the amount of koji mold inoculated into the liquid medium, but about 1 × 10 ⁴ to 1 × 10 ⁶ spores per 1 ml of the liquid medium, and 0.1 to 10 of the preculture solution for mycelia. It is preferable to inoculate about 1%.

  The culture temperature of the koji mold is not particularly limited as long as it does not affect the growth, but it is preferably 25 to 45 ° C, more preferably 30 to 40 ° C. When the culture temperature is low, the growth of Aspergillus is delayed, and contamination with various bacteria is likely to occur. The culture time is suitably 24 to 120 hours.

As the koji mold used in the present invention, it has the ability to produce sugar hydrolyzing enzymes such as glucoamylase, acid-resistant α-amylase, α-amylase and β-glucosidase, and dietary fiber degrading enzymes such as cellulase, β-glucosidase and xylanase. Neisseria gonorrhoeae is preferred. Specifically, as the white Aspergillus kawachii (Aspergillus kawachii) and the like, Aspergillus awamori as black koji (Asperigillus awamori) or Aspergillus niger (Aspergillus niger), the yellow-green koji mold Aspergillus oryzae (Asperigillus oryzae) or Aspergillus soya ( Aspergillus soyae ) etc. are mentioned.

  Aspergillus oryzae is preferably Aspergillus kawachi. Aspergillus niger is preferably Aspergillus awamori. As for Aspergillus, Aspergillus oryzae is preferable. This is because by using these, a sugar hydrolase is highly produced.

  These koji molds can be used either by culturing with one kind of strain or by mixed culturing with two or more kinds of the same or different kinds. There is no problem with using any form of spores or hyphae obtained by preculture, but it is preferable to use hyphae because the time required for the logarithmic growth phase is shortened.

  Any culture apparatus may be used as long as it can perform liquid culture. However, since Neisseria gonorrhoeae needs to perform aerobic culture, it needs to be performed under aerobic conditions in which oxygen and air can be supplied into the medium. Moreover, it is preferable to stir so that the raw material, oxygen, and koji mold in the medium are uniformly distributed in the apparatus during the culture. The stirring conditions and the aeration amount may be any conditions as long as the culture environment can be maintained aerobically, and may be appropriately selected depending on the culture apparatus, the viscosity of the medium, and the like.

  By culturing by the above culture method, a liquid koji having an enzyme activity such as a sugar hydrolase degrading starch can be obtained.

  As used herein, the liquid koji includes a liquid-cultured culture itself, a culture supernatant, a clarified liquid obtained by filtering or centrifuging the culture, a concentrate thereof, and the like. Also, dried liquid koji is equivalent to liquid koji and can be used as an enzyme source as well.

  For example, the liquid koji of the present invention preferably exhibits the following enzyme activity in an unconcentrated state. Each enzyme activity is measured according to the method described in the examples.

  The acid-resistant α-amylase (ASAA) activity is 15 U / ml or more, preferably 18 U / ml or more, more preferably 20 U / ml or more.

  The α-amylase (AA) activity is 250 U / ml or more, preferably 280 U / ml or more, more preferably 300 U / ml or more.

  The glucoamylase (GA) activity is 50 U / ml or more, preferably 60 U / ml or more, more preferably 70 U / ml or more.

The β-glucosidase (BGL) activity is 200 U / ml or more, preferably 300 U / ml or more, more preferably 400 U / ml or more. Since β-glucosidase activity contributes to the production of monoterpene alcohol, which is a characteristic scent of potato shochu, it is useful for obtaining a more concentrated type of potato shochu.

Use of liquid koji The koji liquid koji obtained by the production method of the present invention can be used in the same manner as solid koji as an enzyme source for producing fermented foods and drinks such as shochu, sake, soy sauce, miso, mirin and amazake. it can. The use of the soy liquid soy obtained by the production method of the present invention as an enzyme source for producing soy shochu is particularly preferable because pure shochu is produced.

Manufacture of shochu shochu Manufacture of shochu shochu can be carried out in the same manner as that of shochu shochu using general rice (solid) rice bran. Use it.

  In the present invention, as a fermentation raw material (so-called hanging raw material) for shochu shochu, potatoes such as sweet potato, potato and cassava can be used and are not particularly limited.

  The moss as the raw material can be used as it is, but a freeze-dried product (dried rice cake) or a dried and pulverized product (such as sweet potato powder) can also be used. In addition, these potatoes are subjected to a fermentation process after pretreatment such as steaming, crushing, and shredding after cutting and removing the tip and lesions. What is necessary is just to select suitably according to the enzyme activity of liquid soot, etc.

  Moreover, when manufacturing a shochu shochu using the above-mentioned soot liquid cake, all processes can be performed in a liquid phase. As a method for producing a shochu shochu in which the entire process is performed in a liquid phase, for example, when sweet potato is used as a raw material, the sweet potato is melted and liquefied using a heat-resistant enzyme agent at a high temperature of about 80 ° C. Examples include a method of distilling and producing mash that has been fermented with alcohol by adding the yeast soy liquid koji and yeast by an atmospheric distillation method or a vacuum distillation method.

  Moreover, a part of the obtained liquid soot can also be used as a starter in the next liquid soot production. Thus, by continuously producing the liquid soot, stable production is possible, and at the same time, production efficiency can be improved.

  The liquid koji of the present invention can also be used as a pharmaceutical preparation such as an enzyme preparation and a digestive agent because of its high enzyme activity. In this case, the obtained koji mold culture may be concentrated and purified to a desired degree, and an appropriate excipient, thickener, sweetener and the like may be added to prepare a preparation by a conventional method.

Saccharification of saccharification raw material When saccharifying a saccharification raw material using the liquid koji of the present invention, the sugar hydrolase contained in the liquid koji of the present invention is allowed to act on the saccharification raw material. For example, the saccharified raw material is pretreated as necessary, and then poured into water containing a sufficient amount of liquid soot for the saccharified raw material to be immersed, and statically maintained at a temperature suitable for the enzyme to act. Or shaken or agitated as necessary. As pretreatment of the saccharification raw material, operations such as washing, pulverization, heating, and alkali treatment are generally performed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to these Examples.

Example 1 and Comparative Example 1
芋 Manufacture of liquid candy Aspergillus oryzae, Aspergillus kawachi (NBRC4308 strain), which is a standard strain related to white mold, was prepared.

2. Preculture method 100 ml of a preculture medium having a composition of 65% white barley 8% (w / v), KNO ₃ 0.2% (w / v), KH ₂ PO ₄ 0.3% (w / v), It put into the conical flask with a capacity | capacitance of 500 ml with a baffle, autoclaved at 121 degreeC for 15 minutes, and inoculated the spore 1 platinum ear of the koji mold after cooling at room temperature. Thereafter, rotary shaking culture was performed at a temperature of 37 ° C. and 100 rpm for 24 hours.

3. Main culture method The culture raw material was prepared as follows.

  As Example 1, both ends of raw Koganesengan (those without peeling off the skin) were cut off and 6 g of cut pieces having end portions were collected and used as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  As Comparative Example 1, a meaty portion was obtained by cutting off both ends of a raw Koganesengan (as it was without peeling off the skin). This meaty portion was cut and collected with a weight of 6 g per piece as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

100 ml of a main culture medium (pH non-adjusted) having the composition of the above culture raw materials, KNO ₃ 0.4% (w / v), KH ₂ PO ₄ 0.6% (w / v), and 500 ml baffled triangle The flask was sterilized by autoclaving at 121 ° C. for 15 minutes. After cooling to room temperature, 2 ml of the preculture was inoculated. Then, the rotation shaking culture was performed at 37 degreeC and 100 rpm for 72 hours.

4). Measurement of enzyme activity Enzyme activity was measured using a culture supernatant obtained by centrifugation from the culture medium in which main culture was performed, as a liquid sputum sample. The measuring method is as follows.

Acid-resistant α-amylase (ASAA) activity:
After 9 ml of 100 mM acetate buffer (pH 3.0) was added to 1 ml of the culture supernatant and acid treatment was performed at 37 ° C. for 1 hour, measurement was performed using an α-amylase measurement kit (manufactured by Kikkoman).

5). Measurement Result The measurement result of ASAA activity (U / ml) is shown in FIG.

  According to these results, when a sweet potato piece having a raw sweet potato end is used as a culture raw material (ie, a carbon source of a liquid medium) for producing a liquid liquid koji, when a meat part of the sweet potato is used It was found that ASAA activity was significantly improved.

Example 2 and Comparative Example 2
芋 Manufacture of liquid candy Cultivation and measurement of enzyme activity A phlegm liquid koji was produced in the same manner as in Example 1 except that the culture raw material prepared as follows was used, and ASAA activity (U / ml) was measured.

  As Example 2, 6 g, 9 g, and 12 g of cut ends having raw ends were cut off at both ends of raw Joy White (as it was without peeling the skin), and used as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%, 9 w / v%, and 12 w / v%, respectively.

  As Comparative Example 2, a meaty portion was obtained by cutting off both ends of raw Joy White (as it was without peeling off the skin). This meaty portion was cut and collected with a weight of 6 g per piece as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

2. Measurement Result The measurement result of ASAA activity (U / ml) is shown in FIG.

  Based on these results, when a sweet potato piece having a raw sweet potato end is used as a culture raw material for producing a liquid liquid koji, the ASAA activity of the liquid koji correspondingly increases when the amount of the culture raw material is increased. It has been found.

Example 3 and Comparative Example 3
芋 Manufacture of liquid candy Cultivation and measurement of enzyme activity A liquid liquid koji was produced in the same manner as in Example 1 except that the culture raw material prepared as follows was used.

  FIG. 3 is a schematic view showing the positions where the culture raw materials of Example 3 and Comparative Example 3 were collected with respect to the front view of the cocoon body. The numbers in the figure correspond to the numbers of the culture raw materials described below.

  As Example 3, the head, which is the end portion of the raw Koganesengan (as it is without peeling the skin), was cut off, and 6 g of cut pieces having the head were collected and used as a culture raw material ( Raw material 1). In this case, the carbon source concentration in the liquid medium is 6% w / v%.

  Moreover, the tail part which is the terminal part on the opposite side to the head of raw koganesengan was cut off, and 6 g of cut pieces having the tail part were collected and used as a culture raw material (raw material 2). In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  As Comparative Example 3, 6 g of a meat part was collected from a position shifted from the head of raw koganesengan by 1 cm in the central direction (raw material 3) and from a position shifted from the tail by 1 cm in the central direction (raw material 4) to obtain a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  Further, 6 g of the fleshy material was collected from a position (raw material 5) shifted 2 cm in the central direction from the head of raw koganesengan and a position shifted 2 cm in the central direction from the tail (raw material 6) to obtain a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  In addition, 6 g of a meaty portion was collected from the central position of the raw koganesengan and used as a culture raw material (raw material 7). In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  Subsequently, the ASAA activity (U / ml) of the obtained soot liquid cake was measured in the same manner as in Example 1. Moreover, the glucoamylase (GA) activity of the obtained soot liquid koji was measured as follows.

Glucoamylase (GA) activity:
Measured according to the National Tax Agency prescribed analysis method. Specifically, 0.2 ml of 200 mM acetate buffer (pH 5.0) was added to 1 ml of starch solution and preheated at 40 ° C. for 5 minutes. To this, 0.1 ml of the culture supernatant was added and reacted at 40 ° C. for 20 minutes, and 0.1 ml of 1N sodium hydroxide solution was added to stop the reaction. Thereafter, the mixture was allowed to stand for 30 minutes and neutralized by adding 0.1 ml of 1N hydrochloric acid solution. As a control, add 0.2 ml of 0.2 M acetate buffer to 1 ml of starch solution, preheat at 40 ° C. for 5 minutes, add 0.1 ml of 1N sodium hydroxide solution, and then add 0.1 ml of culture supernatant. Thereafter, the same operation as described above was performed. The amount of glucose produced in the reaction solution was measured using Glucose CII-Test Wako (manufactured by Wako Pure Chemical Industries).

  The glucoamylase activity was expressed with 1 unit of activity to produce 1 mg of glucose from soluble starch at 40 ° C. for 60 minutes.

2. Measurement Results FIG. 4 shows the measurement results of ASAA activity (U / ml) and GA activity (U / ml) of the liquid koji obtained using each culture raw material.

  From these results, it was found that the ASAA activity and the GA activity are high even if the head portion or the tail portion is used as the culture raw material for producing the cocoon liquid koji if it is the end portion of the sweet potato.

Example 4
Saccharification of sweet potato powder 1.0 g of sweet potato powder (manufactured by Nippon Flour Pharmaceutical Co., Ltd.), 49 ml of 100 mM acetic acid buffer (pH 4.0), and 1.0 ml of the straw liquid cake obtained in Example 3 were placed in a 100 ml Erlenmeyer flask. Saccharification was performed under reciprocal shaking at 100 ° C. and 100 rpm. After 4 hours, the glucose concentration of the supernatant was measured with a glucose measurement kit (CII-Test Wako: manufactured by Wako Pure Chemical Industries, Ltd.). The results are shown in FIG.

  As described above, the cocoon liquid koji using the end portion of sweet potato as a culture raw material was superior in saccharification power than the koji liquid koji using the meaty portion of sweet potato.

Example 5 and Comparative Example 4
Use of black koji mold 1. Aspergillus oryzae, Aspergillus awamori (NBRC4388 strain), which is a standard strain for Aspergillus niger, was prepared.

2. Cultivation and measurement of enzyme activity Next, a preculture was prepared and main culture was carried out in the same manner as in Example 1 except that Aspergillus awamori was used as the koji mold.

  The culture raw material used for the main culture was prepared as follows.

  As Example 5, both ends of raw Koganesengan (those without peeling off the skin) were cut off, and the cut ends having end portions were collected and used as a culture raw material. The magnitude | sizes of the cut piece which has a terminal part were 12 g and 18 g. In this case, the carbon source concentration in the liquid medium is 12 w / v% and 18 w / v%, respectively.

  As a comparative example 4, a meat quality portion was obtained by cutting off both ends of a raw koganesen gun (as it was without peeling off the skin). This meat part was cut to obtain a culture raw material. The size of the cut meat part was 12 g and 18 g. In this case, the carbon source concentration in the liquid medium is 12 w / v% and 18 w / v%, respectively.

  The culture supernatant obtained by centrifugation from the culture medium in which the main culture was performed was used as a liquid sputum sample, and the acid-resistant α-amylase (ASAA) activity as in Example 1 and the glucoamylase (ASA) activity in the same manner as in Example 3. GA) activity was measured.

3. Measurement Results FIG. 6 shows the measurement results of ASAA activity (U / ml) and GA activity (U / ml).

  From the results of Example 5 and Comparative Example 4, it was found that when black koji molds are cultured, the cut ends having the end portion of sweet potato give higher GA activity than the meaty portion of sweet potato.

Example 6 and Comparative Example 5
Use of jaundice 1 As a Neisseria gonorrhoeae strain, Aspergillus oryzae (RIB40 strain), which is a standard strain for yellow koji mold, was prepared.

2. Cultivation and measurement of enzyme activity Subsequently, a preculture was prepared and main culture was carried out in the same manner as in Example 1 except that Aspergillus oryzae was used as the koji mold.

  The culture raw material used for the main culture was prepared as follows.

  As Example 6, both ends of a raw Koganesengan (those without peeling off the skin) were cut off, and the cut ends having end portions were collected and used as a culture raw material. The magnitude | sizes of the cut piece which has a terminal part were 9g and 18g. In this case, the carbon source concentration in the liquid medium is 9 w / v% and 18 w / v%, respectively.

  As Comparative Example 5, a meaty portion was obtained by cutting off both ends of a raw Koganesengan (those without peeling off the skin). This meat part was cut to obtain a culture raw material. This meat part was cut to obtain a culture raw material. The size of the cut meat part was 9 g and 18 g. In this case, the carbon source concentration in the liquid medium is 9 w / v% and 18 w / v%, respectively.

  Α-Amylase (AA) activity and glucoamylase (GA) activity were measured using a culture supernatant obtained by centrifuging from the culture solution subjected to main culture as a liquid sputum sample. Glucoamylase (GA) activity was measured in the same manner as in Example 3, and α-amylase (AA) activity was measured in the same manner as in Example 1 except that no acetate buffer was added.

3. Measurement Results FIG. 7 shows the measurement results of AA activity (U / ml) and GA activity (U / ml).

  From the results of Example 6 and Comparative Example 5, it was found that even when cultivated with yellow gonococcus, the cut ends having the end portion of sweet potato give higher enzyme activity than the meat portion of sweet potato.

Examples 7 and 8 and Comparative Example 6
影響 Effect of presence or absence of epidermis Cultivation and measurement of enzyme activity A liquid koji was produced in the same manner as in Example 1 except that the culture raw material prepared as follows was used, and the acid-resistant α-amylase (ASAA) activity and in Example 3 were produced. Thus, glucoamylase (GA) activity was measured.

  As Example 7, both ends of raw Koganesengan (those without peeling off the skin) were cut off and 6 g of cut pieces having end portions were collected and used as culture raw materials. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  As Example 8, both ends of the raw Koganesengan peeled off were cut off and 6 g of cut pieces having end portions were collected and used as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

  As Comparative Example 6, a meaty portion was obtained by cutting off both ends of a raw Koganesengan (those without peeling off the skin). The meaty portion was cut and collected with a weight of 6 g per piece to obtain a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

2. Measurement Results FIG. 8 shows the measurement results of ASAA activity (U / ml) and GA activity (U / ml).

  From the results of Examples 7 and 8 and Comparative Example 6, it was found that the cut piece having the end portion of the sweet potato gives higher enzyme activity than the fleshy portion of the sweet potato both in the peeled state and in the peeled state. did.

Example 9 and Comparative Example 7
Effect of carbon source concentration Cultivation and measurement of enzyme activity A liquid koji was produced in the same manner as in Example 1 except that the culture raw material prepared as follows was used, and the acid-resistant α-amylase (ASAA) activity and in Example 3 were produced. Thus, glucoamylase (GA) activity was measured.

  As Example 9, both ends of a raw Koganesengan (those without peeling off the skin) were cut off, and the cut ends having end portions were collected and used as culture raw materials. The magnitude | sizes of the cut piece which has a terminal part were 3g, 6g, 9g, 15g, 20g, 25g, 30g, 50g, 60g, 70g and 80g. In this case, the carbon source concentration in the liquid medium is 3 w / v%, 6 w / v%, 9 w / v%, 15 w / v%, 20 w / v%, 25 w / v%, 30 w / v%, 50 w, respectively. / V%, 60 w / v%, 70 w / v% and 80 w / v%.

  As a comparative example 7, a meat quality portion was obtained by cutting off both ends of a raw koganesen gun (as it was without peeling off the skin). This meaty portion was cut and collected with a weight of 6 g per piece as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v%.

2. Measurement Results FIG. 9 shows the measurement results of ASAA activity (U / ml) and GA activity (U / ml).

  According to the results of Example 9 and Comparative Example 7, when using a piece having a sweet potato end as a culture raw material, both the ASAA activity and the GA activity are in the range of 3 to 25% with an increase in the amount used in the medium. Increased. In the range of 25 to 60%, the activity is somewhat reduced, but the activity is sufficiently higher than when using the meaty part left by cutting off both ends of the sweet potato.

Example 10
Effect of pre-heating treatment Cultivation and measurement of enzyme activity A liquid koji was produced in the same manner as in Example 1 except that the culture raw material prepared as follows was used, and the acid-resistant α-amylase (ASAA) activity and in Example 3 were produced. Thus, glucoamylase (GA) activity was measured.

  As a non-treated section, it has a cut end having a terminal portion obtained by cutting off both ends of raw Koganesengan (as it is without peeling the skin), and a terminal section obtained by steaming the whole Koganesengan as a heat treatment section and then cutting off both ends. Pieces of 6 g, 9 g, and 12 g were collected as culture raw materials. In this case, the carbon source concentration in the liquid medium is 6 w / v%, 9 w / v, and 12 w / v, respectively.

2. Measurement Results FIG. 10 shows the measurement results of ASAA activity (U / ml) and GA activity (U / ml). Both ASAA activity and GA activity were found to have high activity regardless of the presence or absence of heat pretreatment.

Example 11 and Comparative Example 8
芋 Manufacture of liquid candy Cultivation and measurement of enzyme activity Except for using the culture raw material prepared as follows, a sputum liquid koji was produced in the same manner as in Example 1, and β-glucosidase (BGL) activity (U / ml) was measured. . BGL activity is an enzyme that contributes to the production of monoterpene alcohol, a characteristic scent of potato shochu (Ota, Journal of the Brewing Society; 86 (4), 250-254, 1991). It is expected that a dark shochu can be obtained by using a shochu with high activity.

  As Example 11, both ends of a raw koganesen gun were cut off, and 6 g and 9 g of cut ends having end portions were collected as culture raw materials. In this case, the carbon source concentration in the liquid medium is 6 w / v% and 9 w / v%, respectively.

  As Comparative Example 8, a meat portion that was left by cutting off both ends of a raw Koganesengan was obtained. The meat part was cut and collected with a weight of 6 g and 9 g per piece as a culture raw material. In this case, the carbon source concentration in the liquid medium is 6 w / v% and 9 w / v%, respectively.

  Subsequently, the BGL activity of the obtained soot liquid cake was measured as follows.

BGL activity:
After preheating the mixed solution of 0.5 ml of 50 mM acetate buffer (pH 5.0) to 0.25 ml of 4 mM p-nitrophenyl-β-D-glucopyranoside solution at 37 ° C., 0.25 ml of culture supernatant Was added and mixed well to initiate the reaction. After reacting at 37 ° C. for exactly 15 minutes, 2.0 ml of 200 mM sodium carbonate solution was added and mixed well to stop the reaction. This reaction-terminated liquid was put into an absorbance measurement cell, and absorbance was measured at a wavelength of 410 nm. As the measurement of the blank value, the reaction solution was heated at 37 ° C. for 20 minutes, and after adding 2.0 ml of 200 mM sodium carbonate solution, the absorbance of the solution mixed well after adding the culture supernatant was measured. Based on a calibration curve prepared in advance, the amount of free p-nitrophenol is calculated.

  BGL activity was defined as 1 unit as the titer that acts on p-nitrophenyl-β-D-glucopyranoside to release 1 nmol of p-nitrophenol per minute at 37 ° C.

2. Measurement Result The measurement result of BGL activity (U / ml) is shown in FIG.

  From these results, it was found that a piece having a raw sweet potato end gives higher BGL activity than a meaty part.

1 ... head,
2 ... Tail,
3 ... a part shifted 1 cm from the head toward the center,
4 ... A part shifted 1 cm from the tail toward the center,
5: A portion shifted by 2 cm from the head toward the center,
6: The part shifted 2cm from the tail toward the center,
7 ... Central part.

Claims (7)

  A method for producing a koji liquid koji, comprising a step of culturing koji mold using a liquid medium containing a sweet potato snip having a sweet potato end portion separated from a raw sweet potato body.   2. The method for producing a koji liquid koji according to claim 1, wherein 6 to 60 g of the sweet potato pieces are added to 100 ml of the medium in the liquid medium.   The method for producing a soot liquid koji according to claim 1 or 2, wherein the carbon source in the liquid medium consists only of a piece of the sweet potato.   The sweet potato is selected from the group consisting of Koganesengan, Akemurasaki, Kokei No.14, White Satsuma, White Yutaka, Joy White, Tanegashima Gold, Benihayato, Tanegashima Roma, Anno Red, Anno Kogane, Benissatsuma, Beniotome, Beniazuma, Ayamura Saki and Joy Red The method for producing a soot liquid soup according to any one of claims 1 to 3, wherein the soot is at least one kind.   The method for producing a koji liquid koji according to any one of claims 1 to 4, wherein the koji mold is white koji mold, black koji mold or yellow koji mold.   The method for producing a cocoon liquid koji according to claim 1, wherein the obtained koji liquid koji has an enhanced sugar hydrolase activity.   The method for producing a strawberry liquid koji according to claim 6, wherein the sugar hydrolase is at least acid-resistant α-amylase, α-amylase, glucoamylase, and β-glucosidase.

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