JPH0570120A - Silica gel for stabilization of beer - Google Patents

Abstract

PURPOSE:To obtain a silica gel for the stabilization of beer capable of selectively and exclusively removing the clouding substances in beer. CONSTITUTION:The objective silica gel for the stabilization of beer has the following characteristics. The specific surface area is 200-500m<2>/g, the fine pore volume is 0.5-2.0cc/g, the average pore radius is 60-200Angstrom , the ratio x of the peak intensity at 3500cm<-1> to the peak intensity at 1800 cm<2> in infrared absorption spectrum is 0.5<x<2.5 and the ratio y of the peak intensity at 3750cm<-1> to the peak intensity at 3500cm<-1> in infrared absorption spectrum is 1.0<y<9.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to silica gel for stabilizing beer.

[0002]

BACKGROUND OF THE INVENTION Beer is a fermented product whose main ingredients are malt and hops of barley. In the manufacturing process, proteins and polyphenols derived from the above raw materials are by-produced.
If left in beer without removing these by-products, they colloidally associate during storage and cause turbidity, and especially in light-colored beer, its transparent appearance is lost and the commercial value is significantly impaired. There is a problem.

As a method for preventing such turbidity of beer, it has been attempted to effectively remove proteins and polyphenols that cause turbidity by using tannin, papain, polyvinylpolypyrrolidone (PVPP), silica gel or the like. Has been done. Among them, silica gel is widely used because it does not impair the quality of beer such as foam, aroma and taste.

For example, JP-A-1-165363 discloses a specific surface area of 300 to 700 m ² / g and a pore volume of 1.0 to
It is described that spherical silica gel having an average particle diameter of 5 to 20 μm and a pore size of 2.0 cc / g and an average pore radius of 100 to 180 Å is described. In addition, Japanese Patent Publication No. 3-2748
No. 3, gazette discloses a specific surface area of 530 to 720 m ² / g, a pore volume of 0.9 to 1.5 cc / g, and an average pore radius of 50 to 120.
Å, it is described to use water-containing silica gel having a water content of 7 to 25% by weight (wet weight basis).

[0005]

The mechanism of action of silica gel for stabilizing beer on turbid substances is considered to be due to the selective adsorption of turbid substances on the silica gel pores. The electrostatic trapping removal resulting from the existence state of. The present invention is
It is an object of the present invention to provide silica gel having a high effect of stabilizing beer by optimizing not only the pore structure of silica gel but also the surface properties.

[0006]

The present invention has a specific surface area of 20.
0-500 m ² / g, pore volume 0.5-2.0 cc / g,
The average pore radius is 60 to 200Å, and the infrared absorption spectrum has a peak intensity at 1860 cm ^-1 of 3
The ratio x of the peak intensity at 500 cm ⁻¹ is 0.5 <x <
The silica gel for stabilizing beer is provided in the range of 2.5.

As described above, the cause of turbidity of beer is protein and polyphenol, but the protein in beer is
There are also frothing proteins associated with the key properties of beer, lathering and lathering. Therefore, the beer flavor, flavor,
It is important to selectively remove only turbid proteins and polyphenols without impairing the characteristics of beer such as foam. The physical properties of the silica gel of the present invention are defined from such a viewpoint.

The specific surface area must be in the range of 200 to 500 m ² / g. Specific surface area is 200m ² / g
If it is less than the above, sufficient adsorption capacity cannot be obtained. When the specific surface area exceeds 500 m ² / g, useful components such as foaming proteins may be adsorbed and removed, which is not suitable.

The pore volume should be in the range of 0.5 to 2.0 cc / g. Pore volume is 0.5cc /
If it is less than g, the adsorbed amount of the turbid component may be insufficient, which is unsuitable. When the pore volume exceeds 2.0 cc / g, the mechanical strength of silica gel is insufficient, the silica gel is crushed into fine powder during beer treatment, and it takes time for the subsequent filtration step, which is unsuitable.

The average pore radius must be 60 to 200Å. If the average pore radius is less than 60Å,
It is not suitable because sufficient adsorption capacity cannot be obtained. If the average pore radius exceeds 200Å, useful components such as foaming proteins may be absorbed, which is not suitable.

The silica gel of the present invention is required to exhibit the following infrared absorption spectrum. The infrared absorption spectrum of silica gel shows that siloxane (Si-O-S
i) An absorption peak at 1800 cm ⁻¹ derived from a bond, an absorption peak derived from a silanol group (Si—OH), etc. appear. The absorption peak derived from the silanol group is derived from the absorption peak near 3500 cm ^−1, which is derived from the associative silanol group in which adjacent silanols are associated with each other by hydrogen bond, and the isolated silanol group which does not cause such hydrogen bond. There are two types of absorption peaks near 3750 cm ^-1 .

1860 cm ^-1 derived from a siloxane bond
When the ratio of the peak intensity of 3500 cm ⁻¹ corresponding to the associative silanol group to the peak intensity of x is x, the silica gel of the present invention needs to have a range of 0.5 <x <2.5. .. In this case, a sufficient turbid protein removing effect is exhibited. If x is 0.5 or less, the absolute amount of silanol groups capable of electrostatically removing proteins is too small, which is unsuitable. When x is 2.5 or more,
It is not suitable because the association between silanol groups is extremely advanced and the affinity for turbid proteins is reduced. A more preferable range is 1.0 <x <1.5.

Furthermore, 3 derived from an associative silanol group
To the peak intensity of 500 cm ^-1, when the ratio of the peak intensity of 3750cm ^-1, which derived from the isolated silanol group and y, is preferably in the range of 1.0 <y <9.
When y is 1.0 or less, the association between silanol groups is extremely advanced, and the affinity with the cloudy protein is reduced, which is not suitable. When y is 9 or more, the absolute amount of silanol groups at which proteins can be removed electrostatically is too small, which is unsuitable. The case of 1.1 <y <5 is more preferable.

It is generally known that in a water-containing substance, the possibility of microbial growth increases as the water content increases. If the water content is high, it is not suitable as silica gel for stabilizing beer. is there. From this point of view, it is preferable to keep the water content low, and when the water content is 7% by weight or less, the growth of Escherichia coli, mold and the like can be sufficiently suppressed, and it is more preferable.

The particle size of the silica gel which is finally brought into contact with beer is appropriately selected depending on the separation method of beer and silica gel and the contact time, but the average particle diameter is in the range of 1 to 50 μm. preferable.

The method for producing the silica gel of the present invention is not particularly limited, and various methods can be adopted. The control of the pore characteristics is not particularly limited, and a conventionally known technique can be used. About infrared absorption spectrum,
The means for imparting the above-mentioned physical properties can be achieved, for example, by controlling the firing temperature and time when removing water from the silica hydrogel.

The firing temperature is preferably about 200 to 350 ° C. If the firing temperature exceeds 350 ° C, y
Is not preferable because the value of may become too large. When the firing time is too long, the value of x is 0.
There is a risk that it will be 5 or less. For example, when the firing temperature is 200 ° C., the firing time is suitably about 2 to 36 hours, and when the firing temperature is 300 ° C., the firing time is suitably about 0.1 to 24 hours.

[0018]

The mechanism of removal of turbid substances such as proteins and polyphenols in beer from the silica gel of the present invention is not always clear, but by optimizing the pore structure, only turbid substances can be selectively distinguished from foaming proteins. It seems that it will be possible to remove it. Furthermore, the infrared absorption spectrum is
It is considered to reflect the physical properties of the surface. In the silica gel of the present invention, since the amount of silanol on the surface and the existing form are optimized, it is considered that the turbid substance can be selectively removed based on the electrostatic force.

[0019]

【Example】

(Synthesis of silica gel) An aqueous solution of No. 3 sodium silicate,
It was diluted so that the SiO ₂ conversion concentration would be 5% by weight. While maintaining this at 40 ° C., a 20% by weight aqueous solution of sulfuric acid was added over 10 minutes until pH = 10 while stirring to obtain a partially neutralized silica slurry. While stirring this slurry, the temperature was raised to 70 ° C., and 20% by weight of sulfuric acid was further added over 60 minutes until pH = 6 to obtain a completely neutralized silica slurry. This slurry was washed with water and filtered to obtain silica hydrogel, which was dried and then calcined to obtain silica gel having various physical properties as shown in Table 1.

The pore characteristics of silica gel were measured by the nitrogen adsorption / desorption method. Here, the specific surface area is BET method and the pore volume is B
It was determined by the JT method. The average pore radius is a pore radius showing a volume value of 50% with respect to the total pore volume in the cumulative distribution of the pore volume with respect to the pore radius. The infrared absorption spectrum was obtained by diluting the sample with KBr and measuring the diffuse reflection light.

[0021]

[Table 1]

(Stabilization test of beer) Young beer immediately after main fermentation in a factory was stored at -1 ° C for 1 month, and then each silica gel in Table 1 was added at a ratio of 0.5 g to 1 liter of beer. Was added in and removed by filtration. Store the filtered beer in a constant temperature bath at 50 ° C for 3 days, then 0
It was stored for 24 hours in a thermostatic bath at 0 ° C, and further stored for 20 hours in a thermostatic bath at 20 ° C. The turbidity of this beer was measured at 20 ° C. using a haze meter. The results are shown in Table 2 in EBC turbidity units. For comparison, the measurement results of beer not treated with silica gel are also shown.

(Foam-holding property) The beer immediately after the filtration is 2
It was maintained at 5 ° C., and the measurement was performed according to the sigma value measuring method. (Me
thods of Analysis of the American Society of Brewi
The results are shown in Table 2. For comparison, the measurement results of beer not treated with silica gel are also shown.

[0024]

[Table 2]

[0025]

The silica gel for beer stabilization treatment of the present invention can selectively remove only turbid substances in beer. Moreover, since the foaming protein is not removed, the beer treated with this does not easily cause clouding and has good foam retention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomio Akita 1150 Hazawa-machi, Kanagawa-ku, Yokohama, Kanagawa Prefecture Asahi Glass Co., Ltd. Central Research Laboratory

Claims (3)

[Claims] 1. A specific surface area of 200 to 500 m ² / g, a pore volume of 0.5 to 2.0 cc / g, an average pore radius of 60 to 200 Å
And, in the infrared absorption spectrum, 1860 cm
^A silica gel for stabilizing beer, wherein the ratio x of the peak intensity at 3500 cm ^{-1 to} the peak intensity at ^-1 is in the range of 0.5 <x <2.5. 2. In the infrared absorption spectrum, 3500
to the peak intensity of cm ^-1, the ratio y of the peak intensity of 3750cm ^-1 is 1.0 <beer stabilization processing silica gel claim 1, characterized in that the range of y <9. 3. A method for removing cloudy proteins in beer using the silica gel according to claim 1.