阅读说明：本技术 杀菌方法、杀菌装置 (Sterilization method and sterilization apparatus ) 是由 内藤敬祐 于 2018-05-23 设计创作，主要内容包括：在针对液状物的杀菌方法中,提供在确保杀菌作用的同时进一步抑制了味道的恶化的杀菌方法以及装置。本发明的杀菌方法是如下方法：针对作为水以外的饮品的被处理溶液,实质上不照射发光波长为260nm以下的紫外光,而是照射发光波长为280nm以上320nm以下的紫外光。(Provided are a method and a device for sterilizing a liquid material, which can ensure a sterilizing effect and can further suppress deterioration of taste. The sterilization method of the invention is as follows: a solution to be treated, which is a beverage other than water, is irradiated with ultraviolet light having an emission wavelength of 280nm to 320nm, substantially without being irradiated with ultraviolet light having an emission wavelength of 260nm or less.)

1. A sterilization method is characterized in that,

a solution to be treated, which is a beverage other than water, is irradiated with ultraviolet light having an emission wavelength of 280nm to 320nm, substantially without being irradiated with ultraviolet light having an emission wavelength of 260nm or less.

2. A sterilization device is characterized in that the sterilization device comprises a sterilization chamber,

an ultraviolet light irradiation device is provided along a flow path through which a solution to be treated, which is a beverage other than water, flows, and irradiates ultraviolet light having a main emission wavelength of 280nm to 320nm and substantially no component having an emission wavelength of 260nm or less.

3. A sterilization method is characterized in that,

a solution to be treated as a coffee beverage is irradiated with ultraviolet light having an emission wavelength of 280nm to 320nm and substantially not containing a component having an emission wavelength of 260 nm.

4. A sterilization method is characterized in that,

a solution to be treated as a fruit juice beverage is irradiated with ultraviolet light having an emission wavelength of 280nm to 320nm and substantially not containing a component having an emission wavelength of 260nm or less.

5. A sterilization method is characterized by comprising:

a solution to be treated as an alcoholic beverage is irradiated with ultraviolet light having a main emission wavelength of 280nm to 320nm and containing substantially no component having an emission wavelength of 260nm or less.

Technical Field

The present invention relates to a method and an apparatus for sterilizing drinks other than water.

Background

Conventionally, as a sterilization process using light, there is a sterilization process in which light from an ultraviolet region to a visible region is irradiated with a pulse. In recent years, a sterilization treatment method using ultraviolet light has been desired.

In particular, in the sterilization of foods, sterilization using ultraviolet light (UV sterilization) is considered to be a method which is less likely to deteriorate the taste than heat sterilization. In addition, from the viewpoint of luminous efficiency, it is known that sterilization treatment is performed while suppressing deterioration of taste by irradiating an object with ultraviolet light emitted from a mercury lamp (main emission wavelength is 254nm) using the lamp (see patent documents 1 and 2 below)

Patent document 3 describes a device for irradiating ultraviolet light as a sterilization treatment for fruit juice beverages, fruit jelly, mousse and the like which are foods and drinks. This document describes that sterilization treatment is performed using ultraviolet light of 200 to 300nm, particularly 220 to 280nm (UV-C), as a wavelength region.

Disclosure of Invention

Problems to be solved by the invention

The present invention aims to provide a sterilization method and apparatus for liquid substances, which can ensure sterilization and inhibit the deterioration of taste.

Means for solving the problems

Conventionally, the deterioration of taste of foods including drinks and the like is analyzed by sensory inspection. In contrast, with the recent progress of chemical analysis techniques, quantitative analysis can be performed by an analyzer. The present inventors have newly found the following problems after quantitative analysis by the analyzer: when a liquid material is sterilized by ultraviolet light irradiation, new substances that are not present before treatment are generated or the amount of a specific substance is greatly changed by using light (wavelength 254nm) emitted from a conventionally preferred mercury lamp, which causes a change in taste or odor (flavor).

The sterilization method of the present invention is characterized in that a solution to be treated as a beverage other than water is irradiated with ultraviolet light having an emission wavelength of 280nm to 320nm substantially without being irradiated with ultraviolet light having an emission wavelength of 260nm or less.

It was confirmed that by irradiating the solution to be treated with light having the above wavelength band (UV-B), the generation of root-cause substances such as bitter taste, unpleasant odor components and malodorous components, which are generated when the solution is irradiated with light having a wavelength of 254nm, can be suppressed, and sterilization can be performed while preventing the deterioration of taste.

The sterilization apparatus of the present invention is characterized in that an ultraviolet light irradiation device is provided along a flow path through which a solution to be treated, which is a beverage other than water, flows, and the ultraviolet light irradiation device irradiates ultraviolet light having a main emission wavelength of 280nm to 320nm and substantially containing no component having an emission wavelength of 260nm or less.

Effects of the invention

According to the present invention, a sterilization method and apparatus can be realized which further suppress deterioration of taste while ensuring a sterilization effect.

Drawings

Fig. 1 is a cross-sectional view along a flow path schematically showing a configuration of a main part in an example of a sterilization apparatus according to the present invention.

Fig. 2 is a sectional view taken along line a-a of fig. 1.

Fig. 3 shows emission spectra of the light sources of example 1, example 2, and comparative example 1.

FIG. 4A is the analysis result of the GC/GCMS system for the olfactory recognizer of coffee beverage.

Fig. 4B is a diagram illustrating a change in the drawing mode of the diagram of fig. 4A.

FIG. 5A shows the result of an analysis of apple juice by GC/GCMS sniffer.

Fig. 5B is a graph shown by changing the drawing mode of the graph of fig. 5A.

FIG. 6A shows the results of an analysis of the sniffer GC/GCMS system for lemon juice.

Fig. 6B is a graph shown by changing the drawing mode of the graph of fig. 6A.

FIG. 7A is the analysis result of the GC/GCMS system for the olfactory recognizer of wine.

Fig. 7B is a graph illustrating a change in the drawing mode of the graph of fig. 7A.

Fig. 8 is the result of an analysis of a taste sensor for coffee beverages.

Fig. 9 is a photograph showing the sterilization effect when the ultraviolet light irradiation treatment was performed using the light source of example 1.

Fig. 10 is a graph showing relative values of bactericidal activity at different wavelengths.

Detailed Description

The object to be treated in the sterilization apparatus and the sterilization method of the present invention is a solution to be treated for a beverage other than water. Examples of such a solution to be treated include alcoholic beverages such as wine, japanese liquor and beer, coffee, fruit juice and liquid flavor itself.

Fig. 1 is a cross-sectional view along a flow path schematically showing a configuration of a main part in an example of a sterilization apparatus according to the present invention. Fig. 2 is a sectional view taken along line a-a of fig. 1. In addition, in each drawing, the dimensional ratio in the drawing does not necessarily coincide with the actual dimensional ratio.

The sterilization apparatus includes a reactor 10. The reactor 10 includes a flow path 3 through which the solution 2 to be treated flows and an ultraviolet irradiation device 20 provided along the flow path 3. The ultraviolet irradiation device 20 is configured to emit ultraviolet light having a main emission wavelength of 280nm to 320nm and substantially not containing a component having an emission wavelength of 260nm or less.

In the present specification, light having an emission wavelength of 280nm to 320nm mainly means light having a wavelength band of 280nm to 320nm, which represents a half value of an emission spectrum. The light substantially not containing a component having an emission wavelength of 260nm or less means light not containing a component having an emission wavelength of 260nm or less in a wavelength band representing a half value of an emission spectrum.

The reactor 10 has a cylindrical outer tube 11 and a cylindrical inner tube 12 which are coaxially arranged. The flow path 3 of the treatment target solution 2 is formed by a region sandwiched between the inner peripheral surface of the outer pipe 11 and the outer peripheral surface of the inner pipe 12.

The material constituting the outer tube 11 in the reactor 10 is not particularly limited, and a metal material such as stainless steel can be used, for example. As a material constituting the inner tube 12 in the reactor 10, any material may be used as long as it transmits ultraviolet light from the ultraviolet light irradiation device 20, and for example, quartz glass or the like can be used.

The ultraviolet irradiation device 20 is disposed inside the inner tube 12 in the reactor 10 along the central axis 5 of the reactor 10. As described above, the ultraviolet irradiation device 20 includes a light source that emits ultraviolet light whose main emission wavelength is 280nm to 320nm and which substantially does not include a component having an emission wavelength of 260nm or less. When light having an emission wavelength including a component of 260nm or less (for example, light from a low-pressure mercury lamp (a bright line of 254 nm)) is emitted to the treatment target solution 2, the taste of the treatment target solution 2 is deteriorated. This will be described later with reference to the embodiments.

As the light source used as the ultraviolet light irradiation device 20, for example, a XeBr excimer lamp (peak wavelength: 283nm) in which a mixed gas of Xe and Br is sealed as a discharge gas can be used₂An excimer lamp (peak wavelength: 289nm), an XeCl excimer lamp (peak wavelength: 308nm) in which a mixed gas of Xe and Cl is sealed as a discharge gas, and the like.

As a light source used as the ultraviolet light irradiation device 20, for example, an ultraviolet light emitting fluorescent lamp can be used. The ultraviolet light emitting fluorescent lamp irradiates a phosphor with light emitted from an excimer generated by dielectric barrier discharge as excitation light, and emits ultraviolet light in a specific wavelength range obtained by excitation of the phosphor as emission light. As the phosphor, for example, bismuth-activated yttrium aluminum borate or the like which emits ultraviolet light having a peak wavelength of 290nm by excitation can be used. Further, cerium-activated lanthanum phosphate or the like having a broad emission peak with a peak wavelength of around 320nm and a half width can be used as the phosphor by excitation.

As a light source used in the ultraviolet light irradiation device 20, an LED element configured to emit light having an emission wavelength of 280nm to 320nm and substantially not containing a component having an emission wavelength of 260nm or less can be used.

The ultraviolet irradiation amount of the ultraviolet irradiation device 20 to the solution 2 to be treated is preferably 170mJ/cm, for example²Above, more preferably 170 to 500mJ/cm². By making the ultraviolet irradiation amount 170mJ/cm²As described above, the sterilization treatment can be performed while suppressing the change in the taste and smell of the solution to be treated 2 itself.

The diameter of the flow path 3 in the reactor 10, i.e., the distance between the inner peripheral surface of the outer tube 11 and the outer peripheral surface of the inner tube 12 is preferably 0.05 to 1mm, for example. With this configuration, even when the solution to be treated 2 is made of a material having a low transmittance of ultraviolet light from the ultraviolet light irradiation device 20 (for example, when 99% of the amount of ultraviolet light irradiated to the solution to be treated 2 is opaque), the solution to be treated 2 can be uniformly sterilized.

The flow rate of the solution 2 to be treated flowing through the flow path 3, the size of the ultraviolet light irradiation region in the flow path 3 (i.e., the length of the flow path 3 in the direction of the light source included in the ultraviolet light irradiation device 20), and other conditions can be appropriately set so that the ultraviolet light irradiation amount is within the above-described specific range.

In the above-described sterilization apparatus, while the solution 2 to be processed is introduced into the flow path 3 and flows through the flow path 3, the ultraviolet light of the wavelength band emitted from the ultraviolet light irradiation device 20 is irradiated to the solution 2 to be processed, thereby performing sterilization processing of the solution 2 to be processed. As a result, as shown in the results of the examples described later, the sterilization effect can be exhibited while suppressing deterioration of the taste of the solution 2 to be treated as a drink.

While the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made. For example, the reactor 10 is not limited to the above-described structure as long as the ultraviolet irradiation device 20 is provided along the flow path through which the solution 2 to be treated flows.