JPH0329386B2 - - Google Patents

Description

[Detailed description of the invention]

B. Field of industrial application of the invention This invention relates to a method for improving the quality of distilled spirits. Conventional technology Alcoholic beverages produced by simple distillation (shochu, whiskey,
Brandy, etc.) contains higher fatty acids and their esters, and these components can crystallize and form flocculent precipitates during cold seasons, or can be oxidized and cause an oily odor. Decrease product value. The methods currently used to remove higher fatty acids and their esters are cold filtration,
There are two activated carbon adsorption methods. The cooling filtration method takes advantage of the crystallization of the above-mentioned esters due to cooling and removes them by filtration, but the equipment costs are high because a refrigerator and a large heat-insulating tank are required, and crystallization cannot be completely prevented. It has the disadvantage that it takes a long time to complete. In the activated carbon adsorption method, several hundred ppm of activated carbon is added to adsorb the above esters and remove them by filtration, but activated carbon lacks adsorption selectivity and has no effect on the quality of sake (taste, aroma, color). big. Furthermore, since the activated carbon is disposable, it is costly. Problems to be Solved by the Invention The present invention is capable of improving the quality of distilled spirits by selectively removing higher fatty acids and their esters while leaving lower fatty acids and their esters, which are flavor components of distilled spirits, remaining. The purpose of the present invention is to provide a method that can be used, has low equipment costs, and low running costs. (b) Means for solving the structural problems of the invention The method for improving the quality of distilled spirits according to the present invention is based on dealuminated Y having a SiO ₂ /Al ₂ O ₃ molar ratio of 10 or more.
type zeolite and SiO ₂ /Al ₂ O ₃ molar ratio of 50 or more
It is characterized by bringing distilled liquor into contact with an adsorbent made of one or more zeolites selected from the group consisting of ZSM-5 type high silica zeolites. The dealuminated Y-type zeolite is
It is preferable that the SiO ₂ /Al ₂ O ₃ molar ratio is 10 or more. Pentasil-type zeolite is a high-silica zeolite represented by ZSM-5, and its SiO ₂ /
It is preferable that the Al ₂ O ₃ molar ratio is 50 or more. The adsorbent may be used either by adding a predetermined amount to distilled liquor and treating it in batches, or by continuously treating it in a fixed bed type. The treatment temperature may be room temperature, and heating and cooling are not necessary. The amount of adsorbent used depends on the amount of higher fatty acids and their esters, but it is usually 500~
A ratio of about 1000 ppm is preferable. In any method, the spent zeolite is treated with a suitable solvent,
For example, ethyl alcohol, propyl alcohol,
It can be regenerated and reused by contacting with butyl alcohol or amyl alcohol aqueous solution. However, since the object is food, it is desirable to use an ethyl alcohol aqueous solution, which is harmless and non-toxic. When an aqueous ethyl alcohol solution is used for regeneration, it is desirable that the alcohol concentration is higher than the alcohol concentration of the distilled liquor, preferably at least 10% higher, since this further reduces the amount of solvent used. There is no higher limit, but if it exceeds 60%, it will be treated as dangerous goods and will be subject to legal restrictions, so 60%
The following are preferred. The temperature at which spent zeolite is regenerated by contacting it with a solvent may be room temperature, but the regeneration time can be shortened by increasing the temperature. In this case, the heating temperature is preferably 60° C. or lower from the viewpoint of saving energy consumption. In addition, when using a fixed bed flow type adsorption tower, it is better to pass the regenerating liquid in the opposite direction to that during the adsorption treatment of distilled liquor. The physical and chemical properties of higher fatty acids and their esters include: a) Solubility in alcohol is highly temperature dependent. b Solubility is highly dependent on alcohol concentration. c It is hydrophobic because it has a long alkyl group. It has properties such as. Among these, the cooling method utilizes property a, and the activated carbon adsorption method utilizes property c. In the case of activated carbon, it adsorbs not only hydrophobic compounds but also compounds with polar groups, so it has a very large effect on taste, aroma, and color, and if the amount used is incorrect, it will have a big impact on the quality of sake. Since the adsorbent of the present invention selectively adsorbs strongly hydrophobic substances, the influence on alcohol quality is small. It is well known that silica-rich zeolites exhibit hydrophobic properties. However, regarding the present invention, ferrierite has no effect at all in dealuminated mordenite even if there is a lot of silica, but dealuminated Y with less silica
Since zeolite-type zeolites exhibit high selectivity, this cannot be explained solely from the perspective of hydrophobicity. Example 1 Shochu (alcohol concentration 43 vol%) 200 c.c. was obtained by simple distillation of a predetermined amount of Y-type zeolite (SiO ₂ /Al ₂ O ₃ molar ratio 14) dealuminated by high-temperature steam treatment.
After stirring at room temperature for 30 minutes, the mixture was filtered through 5B filter paper (Toyo Filter Paper). The analysis was performed by gas chromatography, and the selectivity of adsorption was determined from the removal rate of ethyl caprate, a lower fatty acid ester, and the removal rate of ethyl palmitate, a higher fatty acid ester. The raw materials contained ethyl caprate at 15 ppm and ethyl palmitate at 6 ppm. The results are shown in Table 1. In the dealuminated Y-type zeolite used in Example 1, ethyl palmitate was selectively adsorbed and removed. Furthermore, ethyl C ₁₈ unsaturated fatty acids, which are precursors to oily odor, could also be removed in the same way as ethyl palmitate. Furthermore, 100 c.c. per gram of zeolite after adsorption treatment.
A 60 vol% ethyl alcohol aqueous solution was added thereto, and after stirring at room temperature for 30 minutes, it was filtered and dried. When adsorption experiments were conducted again using the dried zeolite, the adsorption performance did not change at all before and after regeneration. That is, it has been completely regenerated. Example 2 An adsorption test was conducted in the same manner as in Example 1 using ZSM-5 with a SiO ₂ /Al ₂ O ₃ molar ratio of 80. Table 1 shows the results. ZSM- used in Example 2 as shown in Table 1
Ethyl palmitate was selectively adsorbed and removed by 5 zeolite. Furthermore, ethyl C ₁₈ unsaturated fatty acids, which are precursors to oily odor, could also be removed in the same way as ethyl palmitate. The used adsorbent was regenerated and reused in the same manner as in Example 1, but the adsorption performance did not change at all before and after regeneration.

[Table] Comparative Example 1 Commercially available Y-type zeolite (SiO ₂ /Al ₂ O ₃ molar ratio
4.8), an adsorption experiment was conducted in the same manner as in Example 1. As shown in Table 2, Y-type zeolite that was not dealuminated did not adsorb ethyl palmitate at all even when 1000 ppm was added. Comparative example 2 Commercially available mordenite (SiO ₂ /Al ₂ O ₃ molar ratio 10)
Mordenite with a high SiO ₂ /Al ₂ O ₃ ratio was prepared by dealumination using hydrochloric acid, and an adsorption experiment was conducted in the same manner as in Example 1. As shown in Table 2, almost no ethyl palmitate was adsorbed even though 2000 ppm was used. Furthermore, even if the SiO ₂ /Al ₂ O ₃ molar ratio was increased, the adsorption ability of ethyl palmitate did not improve much, but rather it began to adsorb ethyl caprate. Comparative Example 3 Even when ferrierite (SiO ₂ /Al ₂ O ₃ molar ratio = 17), which is a type of high-silica zeolite, was used, as shown in Table 2, it adsorbed only a small amount of ethyl palmitate. Ta. Comparative Example 4 When coconut shell activated carbon with a specific surface area of 900 m ² /g and 20 to 50 meshes was used, as shown in Table 2, not only ethyl palmitate but also ethyl caprate was removed, resulting in poor selectivity and Ta.

【table】

[Table] The samples subjected to the adsorption treatment shown above and the untreated samples were kept at -5°C for one week and the turbidity was visually compared.
The samples treated with the adsorbent having a low adsorption capacity shown in 1. showed turbidity, whereas the samples of Examples 1 and 2 and Comparative Example 4 showed no turbidity at all. C. Effects of the invention Since only the substances that cause the formation of flocculent precipitates and the precursors of oily odor are selectively adsorbed, the influence on the quality of alcoholic beverages is small. Since the adsorption operation can be performed at room temperature, energy can be saved compared to the cold filtration method. The equipment cost is lower than the cooling filtration method. If you use a fixed bed type, there is no need for filter paper and you can save on manpower. Processing time is shorter than the cooling filtration method. (In the cold filtration method, the material must be kept at a low temperature for a long time to completely form crystals.) Adsorbent costs are low because it can be easily regenerated.

Claims (1)

[Claims] 1. A group consisting of a dealuminated Y-type zeolite with a SiO ₂ /Al ₂ O ₃ molar ratio of 10 or more and a ZSM-5 type high-silica zeolite with a SiO ₂ /Al ₂ O ₃ molar ratio of 50 or more. A method for improving the quality of distilled spirits, which comprises bringing distilled spirits into contact with an adsorbent made of one or more types of zeolites selected from the following. 2. The method for improving the quality of distilled liquor according to claim 1, wherein the zeolite used as an adsorbent is one obtained by regenerating spent zeolite that has been brought into contact with distilled liquor and brought into contact with an aqueous solution of ethyl alcohol.