BREAD COMPRISING SACCHARIFIED RICE SOLUTION AND METHOD FOR PREPARING SAME

Information

  • Patent Application
  • 20230093128
  • Publication Number
    20230093128
  • Date Filed
    October 15, 2021
    3 years ago
  • Date Published
    March 23, 2023
    a year ago
Abstract
The present invention relates to a bread comprising a saccharified rice solution and a method for preparing same and, more specifically, to a bread comprising a saccharified rice solution prepared by using Aspergillus oryzae koji, Aspergillus kawachii koji, and lees and a method for preparing same. According to the present invention, a saccharified rice solution prepared by using Aspergillus oryzae koji, Aspergillus kawachii koji, and lees is developed, and thus, as compared with an existing saccharified rice solution prepared by using Aspergillus oryzae koji or Aspergillus kawachii koji, sweetness may be reduced, and the amounts of glutamic acid and aspartic acid may be increased, thus giving further enhanced savory taste. Furthermore, various and rich flavors (aroma) may be enhanced. In addition, by addition of the saccharified rice solution of the present invention, a bread having savory taste and various and rich flavors (aroma) may be prepared.
Description
TECHNICAL FIELD

The present invention relates to bread containing a saccharified rice solution and a method for preparing the same and more specifically, to bread containing a saccharified rice solution prepared using Aspergillus oryzae koji, Aspergillus kawachii koji and lees, and a method for preparing the same.


BACKGROUND ART

In general, bread refers to a product by fermenting a mixture of wheat flour as a main ingredient with water, and then baking the resulting product in an oven. Flour, salt, water, yeast, and dairy products are blended to prepare a dough. In this case, nuts or dried fruits are also added thereto. The quality of bread may depend on the ratio of ingredients and the preparation process. The fermentation process is very important in order to produce high-quality bread and greatly affects the physical properties and flavor of the bread.


Recently, research has been conducted on baking using saccharified rice. In the prior art, Korean Patent No. 10-1750154 discloses a rice fermented composition and rice bread having superior effect of aging-retardation and a method of preparing the same, and Korean Patent No. 10-1926741 entitled “natural fermented bread using rice” discloses a method of improving the quality of bread using fermented rice broth. Therefore, the present invention discloses a method of preparing a saccharified rice solution having improved taste and flavor while solving the problems of conventional saccharified rice solutions, and a method of producing bread containing the same.


DISCLOSURE
Technical Problem

Conventionally, a saccharified rice solution has been prepared using Aspergillus oryzae koji or Aspergillus kawachii koji. In this case, the sweetness increases depending on saccharification. However, there is a recent trend in which consumers are averse to sweet flavors. Therefore, the present invention aims at preparing a saccharified rice solution that has improved various and rich flavors including umami and reduced sweetness compared to a conventional saccharified rice solution prepared using Aspergillus oryzae koji or Aspergillus kawachii koji, and developing bread with improved various and rich flavors including umami, containing the saccharified rice solution.


Technical Solution

In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a saccharified rice solution prepared by adding Aspergillus oryzae koji, Aspergillus kawachii koji and lees to rice flour or rice, followed by hydrolysis.


Meanwhile, the rice flour is preferably alpha rice flour.


Meanwhile, the saccharified rice solution is preferably prepared by further adding glucose or rice syrup to the rice flour or rice, followed by hydrolysis.


In accordance with another aspect of the present invention, provided is a flour dough for baking containing the saccharified rice solution.


In accordance with another aspect of the present invention, provided is bread prepared by baking the dough.


Advantageous Effects

The present invention provides a saccharified rice solution that is prepared using Aspergillus oryzae koji, Aspergillus kawachii koji and lees, and thus is capable of reducing sweetness, providing a further enhanced umami taste based on increased contents of glutamic acid and aspartic acid, and improving various and rich flavors (aroma) compared to a conventional saccharified rice solution prepared using Aspergillus oryzae koji or Aspergillus kawachii koji.





DESCRIPTION OF DRAWINGS


FIG. 1 is a graph showing the results of analysis of the physical properties of bread produced using the saccharified rice solution of the present invention.



FIG. 2 is a graph showing the results of analysis of aroma components of bread produced using the saccharified rice solution of the present invention.





BEST MODE

Conventionally, a saccharified rice solution has been prepared using Aspergillus oryzae koji or Aspergillus kawachii koji. In this case, the sweetness increases due to saccharification. However, there is a recent trend in which consumers are averse to sweet flavors. Therefore, the present inventors made extensive efforts to develop a saccharified rice solution that reduces sweetness and improves various and rich flavors including umami, while maintaining the advantages of conventional saccharified rice solutions prepared using Aspergillus oryzae koji or Aspergillus kawachii koji.


The present invention provides a saccharified rice solution prepared by hydrolyzing rice flour or rice to which Aspergillus oryzae koji, Aspergillus kawachii koji and lees have been added.


In the present invention, an optimum process of preparing a saccharified rice solution having a high sensory score was established by mixing Aspergillus oryzae koji with Aspergillus kawachii koji at an optimum ratio of 2.5 to 3.5:6.5 to 7.5, further adding lees thereto and performing efficient starch pre-treatment and sugar supplementation (treatment with glucose and rice syrup). At this time, more preferably, Aspergillus oryzae koji is mixed with Aspergillus kawachii koji at a ratio of 3:7. As described above, the saccharified rice solution prepared using Aspergillus oryzae koji, Aspergillus kawachii koji and lees is capable of reducing sweetness to an appropriate level and improving various and rich flavors (fragrance) including umami compared to a saccharified rice solution prepared using only Aspergillus oryzae koji, or Aspergillus kawachii koji.


In addition, the contents of aspartic acid and glutamic acid showing the umami in the saccharified solution containing only Aspergillus oryzae koji or Aspergillus kawachii koji are 0.016% and 0.033%, respectively, but the contents of aspartic acid and glutamic acid in the saccharified solution containing Aspergillus oryzae koji, Aspergillus kawachii koji and lees are 0.023% and 0.049%, which correspond to 69.5% and 67.3% increases, respectively. As described above, the saccharified rice solution prepared using Aspergillus oryzae koji, Aspergillus kawachii koji and lees according to the present invention exhibits remarkably improved umami compared to a saccharified rice solution prepared using only Aspergillus oryzae koji, or Aspergillus kawachii koji.


Meanwhile, any rice flour may be used as the rice flour without limitation as long as it is known in the art, but the rice flour is preferably alpha rice flour. The alpha rice flour means alpha (α)-starch rice flour (i.e., rice flour gelatinized into alpha-starch).


Meanwhile, in the present invention, the saccharified rice liquid is preferably prepared by hydrolyzing rice flour or rice to which glucose or rice syrup has been further added.


The Aspergillus oryzae koji derived from Aspergillus oryzae and the Aspergillus kawachii koji derived from Aspergillus kawachii were used.


The term “lees” refers to the residue left behind after the liquor ingredient is filtered from raw rice wine or sake (unfiltered liquor), which is also called “sake lees”. Lees contain large amounts of dietary fibers, proteins, amino acids, organic acids and vitamins, as well as enzymes such as amylase and protease. Here, saccharification of Rhizopus oryzae left over lees was used.


Meanwhile, the present invention provides a flour dough for baking containing the saccharified rice solution.


Meanwhile, the flour dough for baking is preferably obtained by performing primary fermentation using strong flour, water, and yeast Saccharomyces cerevisiae SPC-SNU 70-1 (KCTC 12776BP) to prepare a sponge dough, adding the saccharified rice solution of the present invention to the sponge dough and then performing secondary fermentation on the resulting mixture.


Meanwhile, in the present invention, the sponge dough may be prepared under any fermentation conditions that allow yeast strains to grow. Preferably, the dough is mixed at a temperature of 24 to 26° C., is allowed to stand at 22 to 28° C. for 20 to 40 minutes, and is fermented at a low temperature of 4 to 8° C. for 14 to 18 hours. The fermentation at a low temperature for a long time as in the above conditions has advantages of causing accumulation of metabolites and increasing extensibility and flavors of the product. In addition, such a method has a low production risk and high efficiency compared to a straight method.


Meanwhile, in the process of preparing the dough of the present invention, the fermentation is preferably performed such that the dough is mixed at a temperature of 26 to 28° C., intermediate fermentation is performed at a temperature of 25 to 28° C. and a relative humidity of 80 to 90% for 20 to 40 minutes, rounding is performed and aging is performed at a temperature of 25 to 28° C. and a relative humidity of 80 to 90% for 10 to 20 minutes. Through the above process, gluten is rearranged and stabilized to prepare for fermentation.


Also, the present invention provides bread prepared by baking the dough.


Also, the present invention provides bread prepared by baking the dough.


Any dough may be used as the dough for baking as long as it is generally prepared by adding water and the like to wheat flour, and if necessary, by adding salt (preferably refined salt), refined sugar, shortening, or the like thereto.


The term “baking” used herein generally means a process of baking to produce bread, and specifically refers to a method of baking using dry heat in an oven. Since a known conventional method can be used, a detailed description thereof will be omitted.


As can be seen from the following example, the present invention provides a saccharified rice solution that is prepared using an Aspergillus oryzae koji, an Aspergillus kawachii koji, and lees and thus is capable of reducing sweetness and improving various and rich flavors (fragrance) including umami taste, compared to a conventional saccharified rice solution prepared using Aspergillus oryzae koji or Aspergillus kawachii koji. Also, bread having excellent various and rich flavors (fragrance) including umami taste can be produced using the saccharified rice solution.


Hereinafter, the present invention will be described in more detail with reference to the following examples. The scope of the present invention is not limited to the examples, and encompasses modifications of the technical concept equivalent thereto.


Example 1: Preparation of Saccharified Rice Solution Using Aspergillus oryzae Koji and Aspergillus kawachii Koji of Present Invention

In this example, an optimal process for preparing a saccharified rice solution having excellent sensory scores was established by setting an optimal mixing ratio of Aspergillus oryzae koji to Aspergillus kawachii koji and then further performing efficient starch pre-treatment and sugar supplementation (treatment with glucose and rice syrup).


1) Analysis Method


For analysis of the saccharified rice solution, pH, TTA (measurement of acidity), Brix (measurement of sweetness), organic acid, free sugar, and free amino acid were analyzed and sensory evaluation was performed.


Specifically, pH analysis was performed by homogenizing a mixture of 5 g of a sample with 95 mL of distilled water and then measuring the pH of the resulting sample three times using a pH meter. For TTA analysis, the appropriate amount of NaOH was measured in accordance with 6.8.1.1 Acidity, 6. the Food Standards Test Method, 8. General Test Method, in Food Codex. For Brix analysis, the refractive index of the saccharometer was measured in accordance with 2.1.4.1 saccharide, 2. Food Ingredients Test Method, 8. General Test Method in Food Codex. For sensory evaluation, properties, taste, texture, and color were evaluated in accordance with 1.1 Property (sensory evaluation), 1. Food General Test Method, 8. General Test Method in Food Codex.


In addition, the organic acids, free sugars, and free amino acids were assayed by instrumental analysis, and detailed analysis conditions are shown in Tables 1 to 3.









TABLE 1





Organic acid assay
















Analytical
UPLC (Waters, USA) Model name: Acquity UPLC


Instrument



Column
Unison US-C18 (Imtakt, USA) 250 × 4.6 mm, 5 μm


Detector
PDA (Waters, USA)


Analysis
Mobile Phase: 0.1% phosphoric acid


conditions
Flow rate: 0.7 ml/min



Column Temperature: 25° C.



Sample Temperature: 20° C.


Sample
2 g of sample is diluted 10x with tertiary DW (w/w %),


preparation
followed by mixing under vortexing.



After centrifugation, the supernatant is diluted at a suitable



ratio for analysis (final dilution ratio of 1/20), and then



filtered through 0.45 μm filter.



Instrumental analysis
















TABLE 2





Free sugar analysis
















Analytical
HPLC (Shiseido, USA) Model name: Nanospace S1-2


Instrument



Column
Carbohydrate High Performance (Waters) 4.6 × 450 mm,



4 μm


Detector
RID (Shiseido, USA)


Analysis
Mobile Phase: 80% Acetonitrile


conditions
Flow rate: 1 ml/min



Column Temperature: 35° C.


Sample
2 g of sample is diluted 10x with tertiary DW (w/w %),


preparation
followed by mixing (under vortexing, product (bread):



Sonication 5 min)



After centrifugation, the supernatant is diluted at a suitable



ratio for analysis and then filtered through 0.45 μm filter,



(final dilution ratio: material 1/100, product (bread) 1/10)



Instrumental analysis
















TABLE 3





Free amino acid assay
















Analytical
HPLC (Thremo Dionex, USA) Model name: Dionex Ultimate


Instrument
3000


Column
Inno Cl8 column (YoungJin Biochrom, Korea) 4.6 × 450 mm,



5 μm


Detector
FL Detector (Agilent, USA)


Analysis
Mobile Phase A: 40 mM Sodium phosphate, pH 7


conditions
Mobile Phase B: 3DW/Acetonitrile/Methanol (10:45:45 v/v %)



Flow rate: 1.5 ml/min



Column Temperature: 40° C.



Sample Temperature: 20° C.


Sample
2 g of sample is diluted 10x with tertiary DW (w/w %),


preparation
followed by mixing under vortexing



After centrifugation, the supernatant is diluted at a suitable



ratio for analysis and then filtered through 0.45 μm filter.



Instrumental analysis









2) Setting Optimal Mixing Ratio of Saccharified Rice Solution Using Aspergillus oryzae Koji and Aspergillus kawachii Koji


In the present invention, a saccharified rice solution exhibiting excellent sensory properties was prepared using Aspergillus oryzae koji and Aspergillus kawachii koji, instead of malt, which is generally used as an enzyme source. During the saccharification process, Aspergillus oryzae formed in Aspergillus oryzae koji, produces saccharides, decomposes rice proteins to produce amino acids, and creates a mild sweetness. In addition, Aspergillus kawachii formed in Aspergillus kawachii koji produces various organic acids, especially fresh acidic flavor (citric acid). Based thereon, Aspergillus kawachii can create a variety of tastes (sour taste and umami taste) than conventional saccharified liquids (e.g., Sikhye (Korean traditional rice beverage).


Meanwhile, in the present invention, it was attempted to set the optimal mixing ratio of Aspergillus oryzae koji to Aspergillus kawachii koji. For this purpose, saccharified rice solutions were prepared by varying the mixing ratio of Aspergillus oryzae koji to Aspergillus kawachii koji, the pH, TTA, Brix, total organic acid content, total free sugar content, and total free amino acid content of the saccharified rice solutions were measured and sensory evaluation was performed. The results are shown in Table 4. In addition, the results for detailed components of metabolites, organic acids, free sugars, and free amino acids are shown in Table 5. Based thereon, it was possible to calculate the optimal mixing ratio (2.5-3.5:6.5-7.5) of Aspergillus oryzae koji to Aspergillus kawachii koji, which had the best sensory score.














TABLE 4






TI
T2
T3
T4
T5




















Hard rice
21.74
21.74
21.74
21.74
21.74



Aspergillus

10.87
15.22
21.74
0
6.52



oryzae koji









Aspergillus

10.87
6.52
0
21.74
15.22



kawachii koji








Feed water
56.52
56.52
56.52
56.52
56.52


Total
100
100
100
100
100


Remarks

Aspergillus


Aspergillus


Aspergillus


Aspergillus


Aspergillus





oryzae


oryzae


oryzae


kawachii


oryzae




koji:Aspergillus
koji:Aspergillus
koji
koji
koji:Aspergillus




kawachii


kawachii

100%
100%

kawachii




koji = 5:5
koji = 7:3


koji = 3:7


Brix
43.3
43.4
45.3
42.8
42.1


(Sweetness







measurement)







pH
4.47
4.79
5.94
3.92
4.18


TTA
5.98/12.29
4.03/10.02
1.07/5.73
12.14/19.38
8.35/14.82


(Acidity







measurement)







Total organic acid
0.217
0.156
0.033
0.300
0.273


(%)







Total free sugar
30.328
30.244
32.482
28.795
26.891


(%)







Total free amino
0.378
0.414
0.395
0.338
0.371


acid







(%)







Sensory score
5.84
5.59
3.41
4.52
7.21


(9-point scale)





















TABLE 5





Analysis items
Tl
T2
T3
T4
T5





















Organic
Malic acid
0.063
0.058
0.024
0.041
0.021


acid
Lactic acid
0.021
0.006
0.000
0.099
0.067


(%)
Acetic acid
0.000
0.000
0.000
0.000
0.000



Citric acid
0.000
0.000
0.000
0.000
0.000



Succinic acid
0.124
0.084
0.000
0.152
0.186



Fumaric acid
0.009
0.009
0.009
0.008
0.000



Total
0.217
0.156
0.033
0.300
0.273


Free sugar
Fructose
0.000
0.000
0.000
0.000
0.000


(%)
Glucose
23.369
25.381
27.353
23.951
22.528



Sucrose
0.000
0.000
0.000
0.000
0.000



Maltose
6.959
4.862
5.129
4.844
4.363



Lactose
0.000
0.000
0.000
0.000
0.000



Total
30.328
30.244
32.482
28.795
26.891


Free
Aspartic acid
0.017
0.019
0.027
0.014
0.016


amino acid
Glutamic acid
0.036
0.041
0.047
0.028
0.033


(%)
Asparagine
0.019
0.019
0.014
0.015
0.017



Serine
0.015
0.018
0.025
0.009
0.013



Glutamine
0.028
0.033
0.028
0.016
0.022



Histidine
0.011
0.010
0.007
0.009
0.010



Glycine
0.009
0.011
0.015
0.005
0.007



Threonine
0.011
0.015
0.019
0.006
0.009



Arginine
0.002
0.001
0.001
0.062
0.038



Alanine
0.024
0.028
0.032
0.017
0.021



GABA
0.002
0.003
0.005
0.002
0.002



Tyrosine
0.028
0.030
0.024
0.024
0.026



Valine
0.022
0.026
0.027
0.011
0.018



Methionine
0.011
0.012
0.011
0.009
0.010



Ornithine
0.000
0.000
0.000
0.000
0.000



Tryptophan
0.008
0.009
0.008
0.008
0.009



Phenylalanine
0.030
0.032
0.016
0.026
0.028



Isoleucine
0.015
0.019
0.020
0.007
0.011



Leucine
0.048
0.050
0.039
0.041
0.045



Lysine
0.025
0.023
0.014
0.020
0.024



Proline
0.017
0.016
0.017
0.019
0.014



Total
0.378
0.414
0.395
0.338
0.371









3) Preparation of Saccharified Rice Solution at Optimum Mixing Ratio of Aspergillus oryzae Koji to Aspergillus kawachii Koji Using Addition of Sugar Supplementation


The sugar content in the saccharified rice solution prepared at the optimal mixing ratio of Aspergillus oryzae koji to Aspergillus kawachii koji (2.5˜3.5:6.5˜7.5) was corrected and sugar supplementation was performed to prevent quality deviation. In order to confirm the optimal sugar supplementation, pH, TTA, Brix and total free sugar content of the saccharified rice solution prepared by changing the mixing ratio of supplemented sugar components (glucose, sugar, rice syrup) were measured and sensory evaluation was performed. The results were as shown in Table 6, which shows that the experimental group supplemented with glucose and rice syrup had the best sensory score as the harmony of sweetness was the best.















TABLE 6






T6
T7
T8
T9
T10
T11





















Hard rice
21.74
21.74
21.74
21.74
21.74
21.74



Aspergillus

6.52
6.52
6.52
6.52
6.52
6.52



oryzae koji










Aspergillus

15.22
15.22
15.22
15.22
15.22
15.22



kawachii koji









Feed water
56.52
56.52
56.52
56.52
56.52
56.52


Total
100
100
100
100
100
100


Glucose
25
0
0
12.5
0
12.5


Rice syrup
0
25
0
0
12.5
12.5


Sugar
0
0
25
12.5
12.5
0


Remarks
Glucose
Rice syrup
Sugar
Glucose,
Sugar, rice
Glucose,






sugar
syrup
rice syrup


Brix
41.6
40.3
43.9
43.2
42.1
42.1


pH
4.04
4.07
4.02
4.04
4.01
4.18


TTA
6.44/11.13
6.71/12.02
6.57/11.31
6.33/11.01
7.13/12.50
8.35/14.82


(Acidity








measurement)








Total free sugar
31.850
22.790
31.110
31.090
27.030
26.891


(%)








Sensory score
5.25
5.09
5.46
6.84
6.45
7.14


(9-point scale)















4) Preparation of Saccharified Rice Solution Prepared at Optimum Mixing Ratio of Aspergillus oryzae Koji to Aspergillus kawachii Koji, while Performing Sugar Supplementation and Varying Starch Pre-Treatment Process


A saccharified rice solution was prepared at the optimal mixing ratio of Aspergillus oryzae koji to Aspergillus kawachii koji (2.5˜3.5:6.5˜7.5), while performing sugar supplementation and changing starch pre-treatment (gelatinization, a-starch). The pH, TTA, Brix and total free sugar content of the saccharified rice solution were measured and sensory evaluation thereof was performed. The moisture content of hard rice prepared by the gelatinization process was calculated, the content of alpha rice flour (rice flour) prepared by the a-starch preparation process was reduced, and the feed water content was increased to adjust the content of the starch used for saccharification to a similar level thereto. The results of total organic acids, total free sugars, total free amino acids and sensory scores after starch pretreatment (gelatinization, a-starch) were overall similar (Table 7). Therefore, it is possible to use alpha rice flour (rice flour) instead of hard rice in the preparation process. Based thereon, it is possible to shorten the process of preparing hard rice and pulverize raw materials and thereby to improve shelf life and production workability.











TABLE 7






T12
T13

















Hard rice
21.74
0



Aspergillus

6.52
6.25



oryzae koji






Aspergillus

15.22
14.58



kawachii koji





Feed water
56.52
64.58


Alpha rice flour
0
14.58


(Rice flour)




Total
100
100


Glucose
12.5
12.5


Rice syrup
12.5
12.5


Total
125
125


Brix
42.1
41.9


pH
4.18
4.31


TTA
8.35/14.82
8.16/14.97


(acidity




measurement)




Total organic acid
0.273
0.316


(%)




Total free sugar
26.891
25.881


(%)




Total free amino
0.371
0.378


acid (%)




Sensory score
7.21
7.29


(9-point scale)









Example 2: Preparation of Saccharified Rice Solution Using Aspergillus oryzae Koji, Aspergillus kawachii Koji and Lees of Present Invention

In this example, a saccharified rice solution was prepared by adding lees in order to supplement the saccharified rice solution using Aspergillus oryzae koji or Aspergillus kawachii koji in Example 1. In the saccharification process of Rhizopus oryzae remaining in lees, starch is decomposed to produce free sugars and amino acids.


The pH, TTA, Brix, total organic acid content, total free sugar content, and total free amino acid content of the saccharified rice solution prepared by varying the amount of lees while Aspergillus oryzae koji and Aspergillus kawachii koji are used at the optimal mixing ratio were measured and sensory evaluation was performed. The results are shown in Table 8. In particular, as the alpha rice flour content of the starch material increases, the metabolite content and the sensory evaluation score increase. Therefore, among the saccharified rice solutions to which lees were added, T15 was set as the optimal experimental group.













TABLE 8






T14
T15
T16
T17




















Aspergillus

2.65
2.29
2.65
2.39



oryzae koji








Aspergillus

6.35
5.72
6.35
5.74



kawachii koji







Feed water
31.75
29.85
42.33
33.49


Lees
52.91
45.72
42.33
52.63


Alpha rice flour
6.35
16.43
6.35
5.74


(rice flour)






Total
100
100
100
100


Glucose
5.3
5.1
5.3
5.3


Rice syrup
5.3
5.1
5.3
5.3


Total
110.58
110.58
110.58
110.58


Brix
27.7
34.9
26.7
27


(Sweetness






measurement)






pH
4.42
4.27
4.16
4.14


TTA
7.46/13.40
9.11/14.10
7.34/13.10
8.33/13.86


(Acidity






measurement)






Total organic acid
0.3231
0.218
0.280
0.309


(%)






Total free sugar
14.859
16.390
15.641
13.797


(%)






Total free amino
0.394
0.379
0.399
0.391


acid (%)






Sensory score
4.86
6.72
5.18
5.54


(9-point scale)






Remarks
Low alpha

Low lees
High lees



rice flour

content
content



content









Meanwhile, in order to perform sensory evaluation upon addition of lees, the contents of ingredients of free amino acids were further analyzed. As a result, as shown in Table 9, the contents of glutamic acid and aspartic acid, which are amino acids related to umami, in T15 (saccharified rice solution containing lees, Table 8) compared to T5 (saccharified rice solution without lees, Table 4) were high, and the contents of proline, ornithine, and leucine, which were used to create a strong flavor felt in the bread crust, were high. This indicates that the umami taste and flavor are enhanced by the addition of lees.













TABLE 9







Analysis items
T5
T15





















Free
Aspartic acid
0.016
0.023



amino acid
Glutamic acid
0.033
0.049



(%)
Asparagine
0.017
0.023




Serine
0.013
0.019




Glutamine
0.022
0.027




Histidine
0.010
0.014




Glycine
0.007
0.018




Threonine
0.009
0.014




Arginine
0.038
0.073




Alanine
0.021
0.042




GABA
0.002
0.003




Tyrosine
0.026
0.030




Valine
0.018
0.021




Methionine
0.010
0.011




Ornithine
0.000
0.006




Tryptophan
0.009
0.027




Phenylalanine
0.028
0.011




Isoleucine
0.011
0.000




Leucine
0.045
0.042




Lysine
0.024
0.036




Proline
0.014
0.032




Total
0.371
0.52










Overall, by addition of lees, it was possible to prepare a saccharified rice solution with enhanced various rich flavor, including umami, while appropriately reducing the sweetness created in the saccharified rice solution using Aspergillus oryzae koji or Aspergillus kawachii koji.


Example 3: Preparation of Bread Using Saccharified Rice Solutions of Examples 1 and 2 and Testing

In this example, bread (plain bread) was prepared using the saccharified rice solutions of Example 1 (containing Aspergillus oryzae koji and Aspergillus kawachii koji) and Example 2 (containing Aspergillus oryzae koji, Aspergillus kawachii koji and lees) and tested.


1) Preparation of Bread (Plain Bread) Using Saccharified Rice Solutions of Examples 1 and 2


The components of the sponge dough (see Table 10 below) were put into a mixer (product name: SK101S MIXER: Japan), kneaded in the second stage for 2 minutes and in the third stage for 1 minute, and mixed such that the final temperature of the dough was 25° C. Then, the dough was allowed to stand at room temperature for 30 minutes, and then primarily fermented in a fermenter at 6° C. for 16 hours to prepare sponge dough. Then, the components of the dough (see Table 10 below) are put into a mixer (product name: SK101S MIXER: Japan), kneaded in the first stage for 1 minute, the sponge dough was added thereto, and the resulting mixture was kneaded in the second stage for 3 minutes and in the third stage for 3 minutes, and mixed such that the final temperature of the dough was 27° C. The dough was intermediate-fermented in a fermenter at 27° C. and a relative humidity of 85% for 30 minutes, was divided into uniform segments, rounded, and aged in a fermenter at 27° C. and a relative humidity of 85% for 15 minutes. After aging, the dough was molded and placed in a bread case. Then, the dough placed in the bread case was fermented at 37° C. and at a relative humidity of 85% for 50 minutes to prepare bread dough. The prepared bread dough was baked in an oven at an upper heat of 170° C. and at a lower heat of 210° C. for 35 minutes, and then was cooled at room temperature until the internal temperature reached 32° C.













TABLE 10








Addition of
Addition of





Example 1
Example 2




Control
saccharified
saccharified




group
rice solution
rice solution



















Sponge
Strong flour
70
70
70


dough
Commercial yeast:
0.7
0.7
0.7




Saccharomyces








cerevisiae (SPC-







SNU 70-1 (KCTC






12776BP)a






Rimusoftb
0.3
0.3
0.3



Feed water
42
42
42


Dough
Strong flour
3
30
30



Refined salt
1.8
1.8
1.8



White sugar
7
7
7



Whole milk powder
3
3
3



Butter
10
10
10



Commercial yeast
0.6
0.6
0.6



Feed water
13
7
8



Example 1
0
10
0



saccharified rice






solution






(T13)






Example 2
0
0
10



saccharified rice






solution






(T15)









a: Saccharomyces cerevisiae SPC-SNU 70-1 (KCTC 12776BP) is derived from Korean Patent No. 10-1551839 (Registration date: Sep. 3, 2015) b: Rimusoft is an emulsifier as a food additive (glycerin fatty acid ester) and represents “Rimusoft super (v)”.


2) Texture and Ingredient Analysis and Sensory Evaluation of Bread


The texture and component analysis, and sensory evaluation of bread prepared using the saccharified rice solutions of Examples 1 and 2 above were performed.


First, the texture (physical property) was compared using a texture analyzer (Stable Micro Systems texture analyzer). As analysis indicators, hardness, cohesiveness, springiness, gumminess, chewiness, and resilience were measured. A higher hardness value indicates higher hardness. Springiness means the degree to which a substance returns to its original state, cohesiveness means the ability of food to retain its original state, gumminess means stickiness, chewiness refers to the degree of swallowing, and resilience refers to a force at which an object is restored after pressed. Each analysis parameter was repeatedly measured in 3 replicates.


As a result, as can be seen from FIG. 1 and Table 11, both bread produced using the saccharified solutions of Examples 1 and 2 had improved overall texture (decreased hardness, increased cohesiveness and resilience, and maintained springiness).















TABLE 11






Hardness
Springiness
Cohesiveness
Gumminess
Chewiness
Resilience





















Control group
1.336
0.863
0.489
0.654
0.564
0.181


Example 1
0.84
0.746
0.513
0.712
0.349
0.194


saccharified








rice solution








Example 2
0.92
0.592
0.542
0.498
0.295
0.213


saccharified








rice solution









Then, the free sugar component was analyzed (see Table 2), and the fragrance component was compared using the GS/MS system (Table 12).










TABLE 12





Analysis system
Operation conditions







GC/MS analysis
*GC Model name: Agilent 7890A



*Inlet temperature: 230° C.



*Column: DB-WAX (60 m × 250 um × 0.25 uM)



*Carrier gas: helium



*Flow rate: 1 ml/min



*Oven temperature program : from 40° C. (5 min)



→ 8° C./min → 230° C. (10 min)



*MS detector: Agilent 5975C MSD (El mode)


SPME analysis
* Fiber: DVB/Carboxen/SPME (Supelco Co.)



* Sample equilibration time



incubation temp. 85° C.



incubation time 30 min









As a result, as can be seen from Table 13, the bread made using the saccharified solution of Example 2 exhibited an increase in various types of sweetness (increased content of several free sugars) compared to the control group, and exhibited an appropriately reduced sweetness compared to bread made using the saccharified solution of Example 1. That is, the bread made using the saccharified solution of Example 2 had an appropriate sweetness.














TABLE 13









Example 1
Example 2





saccharified rice
saccharified rice



Free sugar (%)
Control
solution
solution









Fructose
0.75
1.22
1.10



Glucose
0.46
2.26
1.14



Sucrose
0.00
0.00
0.00



Maltose
2.10
2.04
1.83



Lactose
0.82
0.89
0.94



Total
4.13
6.42
5.01










Meanwhile, sensory evaluation was performed on the saccharified rice solutions of Examples 1 and 2. As a result, as can be seen from Table 14, the sensory score was higher in bread made using the saccharified solutions of Examples 1 and 2 compared to the control group, and in particular, the saccharified rice solution of Example 2 exhibited an improved umami taste compared to the saccharified rice solution of Example 1. This indicates that the umami taste and flavor are enhanced by the addition of lees.












TABLE 14







Saccharified rice
Saccharified




solution of
rice solution of


Analysis items
Control
Example 1
Example 2



















Sensory
Sweetness
4.85
8.26
6.45


evaluation
Saltiness
5.16
5.03
5.71


(9-point
Sourness
4.96
5.24
5.69


scale)
Umami
5.48
6.33
8.17



Overall
5.11
7.21
7.94









Meanwhile, as shown in FIG. 2 and Table 15, the bread prepared using the saccharified solutions of Examples 1 and 2 were detected to have a greater variety of flavor ingredients (Example 1: 17 types, Example 2: 14 types) than the control group (12 types). Bread prepared using the saccharified rice solution of Example 1 was found to have a great amount of alcohol having fruity, floral, and whiskey flavors, and a great amount of aldehyde having savory flavors such as roasted, bread, and almond flavors. Bread made using the saccharified rice solution of Example 2 was found to have great amounts of alcohol having fruity, floral, and whiskey flavor characteristics, aldehyde having savory flavors such as roasted, bread, and almond flavors, and ester having sweet and fresh flavors such as fruity and apple flavors. This is considered to be due to various metabolites produced during the preparation of the saccharified rice solution of Example 2.













TABLE 15







Saccharified
Saccharified




Control
rice solution
rice solution



Flavor Area
group
of Example 1
of Example 2
Description




















Alcohol
Ethanol
38,496,132
91,670,582
160,923,927
Strong,







Alcohol,







Ethereal



Isobutyl alcohol
6,379,861
6,427,139
9,415,984
Wine, malty



3-Methyl-1-butanol

122,146,206

Whiskey







fruity







banana



2-Heptanol
1,469,788


Fresh







lemongrass







herbal floral







fruity



1-Hexanol


4,042,512
Green,







Fruity,







Sweet,







Woody,







Floral



Phenethyl alcohol

73,224,730

Rose-







honey-like



Total
46,345,781
293,468,657
174,382,423



Aldehyde
3-Methylbutane

1,674,724

Chocolate,







Roasted







Bread,







Fruity, Corn







flakes



Hexanal
2,813,624
2,146,948
2,120,518
Fresh,







Green,







Fruity,







Sweaty



2-Amylfuran
2,631,942
2,355,922
2,251,848
Fruity,







Green,







Earthy



Acetoin
2,934,085
4,467,510
3,029,328
Sweet







buttery







creamy







dairy milky







fatty



Nonanal
3,296,232
1,681,528
2,714,667
Waxy,







green, fatty



Furfural

3,909,770

Sweet,







Almond,







Bread



Benzaldehyde

12,784,843
10,714,977
Almond,







Strong,







Bitter,







Cherry



Benzeneacetaldehyde

3,012,631

Honey,







floral



Total
1,675,883
32,033,876
20,831,338



Ketone
2-Heptanone
32,696,033
22,106,778
15,733,276
Fruity,







Spicy,







Sweet,







Grass,







Coconut,







cinnamon



2-Nonanone
59,845,480
32,634,616
29,141,357
Fruity fresh







sweet green







weedy







earthy







herbal



2-Undecanone

11,149,345
8,590,500
Floral and







fatty







pineapple



Total
92,541,513
65,890,739
53,465,133



Ester
Isoamyl formate
93,602,735

146,191,846
Fruity green







apple



Ethyl hexanoate
1,516,859

2,071,142
Sweet,







Fruity,







Green,







Creamy,







Milky,







Balsamic



Hexyl formate

2,531,475

Green waxy







floral herbal







plum apple







cucumber



Ethyl octanoate
14,551,853
4,392,463

Fruity,







Wine, Pear







brandy,







Banana,







Sweet,







Fresh



Diethyl succinate


5,521,844
Fruity







apple,







cooked







apple,







ylang-ylang



Total
109,671,447
6,923,938
153,784,832












Total
360,234,624
398,317,210
402,463,726










Overall, it can be seen from the above results that, using the saccharified rice solution (Example 2) containing Aspergillus oryzae koji, Aspergillus kawachii koji and lees, it is possible to prepare a saccharified rice solution that is capable of reducing sweetness and improving various and rich flavors including umami due to the high contents of glutamic acid and aspartic acid, which are umami taste-related amino acids, compared to the saccharified rice solution containing Aspergillus oryzae koji and Aspergillus kawachii (Example 1).

Claims
  • 1-5. (canceled)
  • 6. A method of preparing a saccharified rice solution comprising adding Aspergillus oryzae koji, Aspergillus kawachii koji and lees to a rice flour or rice, and conducting hydrolysis.
  • 7. The method according to claim 6, wherein the rice flour is alpha rice flour.
  • 8. The method according to claim 6, wherein the saccharified rice solution is prepared by further adding a glucose or rice syrup to the rice flour or rice prior to conducting hydrolysis.
  • 9. A saccharified rice solution prepared by the method of claim 6.
  • 10. A flour dough for baking comprising the saccharified rice solution according to claim 9.
  • 11. A bread prepared by baking the flour dough according to claim 10.
Priority Claims (1)
Number Date Country Kind
10-2020-0176742 Dec 2020 KR national
PCT Information
Filing Document Filing Date Country Kind
PCT/KR2021/014352 10/15/2021 WO