JPH10174570A - Food processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a food processing system capable of effectively utilizing ozone to sterilize food-processing apparatuses and equipments, and foods with high sterilizing power and capable of reusing waste water after it is cleaned. SOLUTION: This food processing system for cleaning and processing foods comprises a sterilizing process in which apparatuses and equipments to be used in the system and foods are sterilized using ozone-containing gas and a process for cleaning foods and processing them. The system also contains a waste water-oxidizing and treating process in which waste water discharged from each process is oxidized with ozone-containing gas, and the ozone- containing gas which has been used in and discharged from the sterilizing process for the apparatuses, equipments and the foods is fed to the waste water- oxidizing and treating process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a food processing system for cooking rice, cutting vegetables and fruits, processing fish meat, and cooking other foods. The present invention relates to a food processing system that treats wastewater used together with cleaning and disinfecting of instruments, equipment and food used in the food processing process.

[0002]

2. Description of the Related Art Conventional sterilization in food processing often uses means such as steam heating and boiling for equipment to be used. For the food itself, means such as addition of a bactericide such as hypochlorous acid or immersion in ozone water is used.

On the other hand, miscellaneous effluent in the processing of foods has a high BOD (Biochemical Ox) containing a high concentration of suspended solids and organic matter.
ygen Demand: Biochemical oxygen demand) wastewater. These wastewaters can be released simply by dilution,
River pollution is a problem.

[0004] On the other hand, such a wastewater treatment technique generally uses an aerobic biological treatment method using activated sludge or the like, but a treatment method using yeast or the like has also been developed.

[0005]

In the conventional food processing technology, sterilization of equipment is mainly performed by heat sterilization, so that heat-resistant food poisoning bacteria and the like are not completely sterilized.
There is also a problem that the bacteria themselves change to have heat resistance. Therefore, the processed food may be contaminated by heat-resistant bacteria. In addition, there is also a problem that bacteria are recontaminated in a drying stage after sterilization by a heat treatment. Furthermore, heat treatment may not be possible for foods such as fruits and vegetables.

[0006] Therefore, heat-resistant bacteria of foods and equipment in food processing are sterilized by an effective method to prevent re-contamination during drying, increase the reliability of food sterilization, and maintain freshness. It is an issue to extend this.

[0007] If wastewater from food processing is discharged only by dilution, it causes pollution of rivers and the like, such as eutrophication and generation of trihalomethane, and also affects the quality of tap water.

[0008] Also, in wastewater treatment, high BOD wastewater increases the scale of treatment equipment and the power used for treatment. A challenge has been to reduce the BOD of wastewater in such food processing, reduce the size of treatment facilities, and save energy.

An object of the present invention is to provide an apparatus for food processing,
An object of the present invention is to provide a food processing system that can safely sterilize instruments and food with high sterilizing power, prevent recontamination during drying, and treat wastewater in food processing.

Another object of the present invention is to provide a cleaning, drying,
It is an object of the present invention to provide a food processing system capable of efficiently using ozone-containing gas used for sterilization and recycling wastewater-treated water to reduce washing water.

[0011]

The gist of the present invention to achieve the above object is as follows.

[1] A food processing system for cleaning and processing food includes a sterilization step of sterilizing utensils, equipment and food used by using an ozone-containing gas, and a step of cleaning and processing food. A food processing system having a wastewater oxidation treatment step of oxidizing wastewater discharged from the process using an ozone-containing gas, and supplying the ozone-containing gas used in the sterilization process of the appliance, equipment and food to the wastewater oxidation treatment step; is there.

[2] The food processing system according to the above, wherein the wastewater discharged from each of the above steps is treated in the wastewater oxidation treatment step to recycle the water for cleaning appliances or food.

[3] In the above-mentioned food processing system, in each step using the ozone-containing gas, the ozone-containing gas is circulated in order from a lower steam partial pressure to a higher steam partial pressure.

[4] The food processing system according to the above, wherein ozone water, alkaline water or acid water generated by electrolysis of water is used as water used in the washing and processing steps of the food.

[5] The food processing system according to the above, wherein a solid-liquid separation means for the wastewater discharged from each of the above steps is provided before the wastewater oxidation treatment step.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Cleaning of utensils, equipment and food
In addition to water, steam, and hot water, at least one of ozone water, acidic water, and strongly acidic water is used. In addition, ozone-containing gas (air) is used for sterilization at the same time as drying. The ozone water can be produced by aerating and dissolving ozone in water, and the acidic water and the strongly acidic water can be produced by electrolyzing water or a saline solution.

When a plurality of appliances, appliances and foods to be cleaned are in a continuous line, a means for introducing and discharging cleaning water and a means for introducing and discharging ozone-containing gas for drying are provided throughout. After washing by flowing washing water, drying and sterilization are performed by passing an ozone-containing gas through.

On the other hand, in the step of oxidizing waste water, a means for bubbling the ozone-containing gas generated by the ozone generator into the waste water of the oxidizing tank is provided in the oxidizing tank for collecting the effluent from each step. Oxidizes pollutants in wastewater.

The ozone generated by the ozone generator is supplied to an ozone water generation step and a wastewater oxidation treatment step after passing through a drying step for appliances, equipment and food. In order to effectively use ozone, the ozone-containing gas is circulated sequentially from a lower partial pressure to a higher partial pressure of steam in each step.

Further, in order to improve the efficiency of oxidation by ozone in the wastewater oxidation treatment step, it is desirable to add solid-liquid separation means for separating solid-liquid from wastewater discharged from each step of food processing. As the solid-liquid separation means, it can be performed by means such as ordinary precipitation separation, centrifugation, and filtration separation. The wastewater separated by the solid-liquid separation means is introduced into a wastewater oxidation treatment tank and supplied with ozone to be oxidized, and solid components such as pollutants are separately treated.

Further, the water after the above-mentioned wastewater oxidation treatment is:
It can be returned to the cleaning process for appliances, equipment and food, and can be recycled and used as primary cleaning water. As a result, the total amount of required water can be reduced.

In addition, acidic water and alkaline water obtained by electrolysis of water can be used as water for processing foods.

In particular, in the rice cooking process, it is preferable to use acidic water in the rice immersion step up to the rice cooking step and to use alkaline water in the rice cooking step.

The production ratio of alkaline water and acidic water by electrolysis is approximately 4: 1 in the ratio of alkaline water to acidic water.
Accordingly, tap water, purified water, or the like may be appropriately mixed and used with the acidic water having a small amount of generation.

In order to enhance the sterilizing effect of the processed food during storage or packaging, it is preferable to provide a step of sterilizing containers used for storage and packaging with ozone water or an ozone-containing gas.

First, most of the fungi are sterilized by heat by using steam or hot water in the washing step of the utensil, equipment and food used in each of the above steps. Furthermore, by using ozone water or acidic water, bacteria are killed by destruction of tissues and destruction of enzyme metabolism.

After that, by exposing to the ozone-containing gas generated from the ozone generator, the adhering water evaporates and the remaining bacteria are sterilized by ozone. Since ozone destroys and sterilizes fungal tissues, it has a strong bactericidal activity against heat-resistant spores.

The above-mentioned ozone-containing gas is consumed in the step of drying appliances, equipment and foods in sterilizing bacteria adhering thereto, but most of the ozone-containing gas remains as it is. for that reason,
This can be used in the ozone water generation step to produce ozone water. Again, ozone is not completely consumed,
Remains in the gas phase. Since the above-mentioned ozone residual gas is further introduced into the wastewater oxidation treatment layer and used for oxidation of pollutants in the wastewater, it can be consumed almost completely, so that the influence on the atmosphere can be reduced.

Ozone is dissolved in water to generate hydroxyl radicals having strong oxidizing power, and oxidatively decomposes organic substances and the like in the water.

The above-mentioned ozone water, acidic water and alkaline water obtained by electrolysis of water have various effects in food processing. For example, ozone water has the effect of improving the flavor of foods in addition to sterilization. Acidic water is known to have the effect of maintaining freshness and improving the water absorption rate of rice grains. On the other hand, alkaline water
Improve the taste of cooked rice, improve the taste of processed bean foods and suppress hardening,
It has the effects of preventing discoloration of meat, making water absorption of dried foods uniform, and excavating.

Therefore, by applying each of the three types of water according to the processed food, the taste can be improved,
The use of additive chemicals can be reduced.

[0033]

Next, the present invention will be specifically described based on examples.

Embodiment 1 FIG. 1 is a schematic diagram showing an embodiment of the food processing system of the present invention. This system includes a food cleaning step 1, a food processing step 2, an appliance cleaning device 3, an ozone generator 4, and a wastewater oxidation treatment device 5.

The food 11 as a raw material is washed in a food washing step 1, and is processed in a food processing step 2 such as cutting and cooking to become a processed food 12. The utensil 15 used in the above steps 1 and 2 is cleaned, sterilized and dried by the utensil cleaning device 3.

In the utensil cleaning device 3, after cleaning the utensil 15 using the water 13 and the treated water 17, the ozone-containing air 14 having a high ozone concentration (10 to 50 g / m ³ ) generated by the ozone generator 4 is discharged. After compressing to 3-10kgf,
Spray for 60 seconds to simultaneously dry and sterilize. The ozone generator 4 (made by Simon) generates ozone using air (or oxygen) as a raw material.

The wastewater 16 from the food washing step 1, the food processing step 2, and the utensil washing apparatus 3 is a wastewater oxidation treatment apparatus 5 having an oxidation treatment tank and an ozone-containing gas aerator.
Will be introduced.

The wastewater having a BOD of 3,000 to 30,000 mg / l is retained in an ozone oxidation treatment tank for a certain period of time, and aerated with an ozone-containing gas at an ozone concentration of 5 to 30 g / m ³ and atmospheric pressure which has passed through the utensil washing device 3. In response, pollutants in the wastewater are oxidized and decomposed by ozone.

The treated water 17 oxidized and decomposed to a BOD of about 1 to 100 mg / l is reused in the primary food washing step 1 or the appliance washing apparatus 3.

When the rice cooker was sterilized by this system, the number of viable bacteria became zero.

[Embodiment 2] FIG. 2 is a schematic view showing another embodiment of the food processing system of the present invention, and shows an example of rice cooking as an example of food processing.

This system comprises a rice washing step 1a, a dipping step 2
a, rice cooking process 2b, rice cooking process 6, ozone generator 4, packaging container sterilizing device 7, utensil washing device 3, ozone water generator 8, waste water solid-liquid separator 9, waste water oxidation treatment device 5
It consists of.

The rice 18 is washed in the rice washing step 1a, immersed in water for a certain period of time in the immersion step 2a, and absorbs water.
b. The cooked rice 20 is packaged in a container in a packaging step 6.

The packaging containers used here are supplied sterilized by the packaging container sterilizer 7. In the packaging container sterilizing apparatus 7, the ozone-containing air 14 having a high ozone concentration (10 to 50 g / m ³ ) generated by the ozone generator 4 is sprayed on the packaging container to sterilize and remove bacteria attached to the container. The utensils used in the respective steps 1a, 2a and 2b are cleaned and cleaned by the utensil cleaning device 3 as in the first embodiment.
Sterilized and dried.

Here, ozone water 21 (ozone concentration of 0.1 to 5 mg / l) having a high sterilizing power generated by the ozone water generator 8 is used as the cleaning water. In the ozone water generator 8, ozone-containing air is bubbled into water in the ozone contact tank to dissolve ozone in the water.

The ozone water generation device 8 includes the utensil cleaning device 3
The air containing the unreacted ozone having an ozone concentration of 5 to 30 g / m ³ used in the step is introduced. The ozone-containing air used in the utensil washing device 3 includes air containing unreacted ozone used in the packaging container sterilizing device 7 (ozone concentration of 3 to 25 g).
/ M ³ ). That is, the above-described steps are connected to sequentially reuse the ozone-containing air 14.

In each of the steps 1a, 2a, and 2b, and the wastewater 16 from the utensil washing device 3, the wastewater from which solids are separated in the wastewater solid-liquid separation device 9 is oxidized by the wastewater oxidation treatment device 5. It is introduced into a tank and oxidized with ozone as in Example 1.

As the ozone-containing air used for the above-mentioned wastewater oxidation treatment, ozone-containing air (ozone concentration 1 to 20 g / m ³ ) introduced through the ozone water generator 8 is introduced and reused. The treated water 17 is supplied to the apparatus washing apparatus 3 or the rice washing step 1a.
Reused in

FIG. 3 is an explanatory diagram of an ozone utilization system flow in this embodiment. The air or oxygen 22 which is an ozone raw material is introduced into the ozone generator 4 and ozone is generated to become ozone-containing air 14. This is introduced into the packaging container sterilizing device 7 having the dryest atmosphere, and then used in the drying step 3b of the utensil cleaning device 3.

The ozone-containing air 14 containing a small amount of water in the drying step 3b is then supplied to the ozone water generator 8, passes through the water to generate ozone water, and is introduced into the wastewater oxidation treatment apparatus 5.

The exhaust gas 23 oxidized from the waste water in the waste water oxidation treatment device 5 is subjected to an exhaust gas treatment (not shown), becomes ozone-free, and is released into the atmosphere.

As described above, the ozone-containing air is circulated in order from a device having a lower partial pressure of water vapor to a device having a higher water vapor partial pressure.
Ozone can be used efficiently.

Embodiment 3 FIG. 4 is a schematic diagram showing another embodiment of the food processing system of the present invention.

This system shows an example of the application of electrolyzed water in the rice cooking process. The system is configured by adding an electrolyzed water generator 10 to the configuration shown in FIG. 2 of the second embodiment. .

The electrolyzed water generator 10 electrolyzes the introduced water in an electrolyzer to form alkaline water 25 having a pH of 8 to 10.
And the acidic water 24 of pH 3-6 is produced.

The acidic water 24 is used in the rice immersion step 2a, and the alkaline water 25 is used in the rice cooking step 2b.

By using acidic water 24 having a pH of 4.5 to 5.5 as immersion water, the water absorption rate of rice can be increased, and by using alkaline water having a pH of 8 to 9 as water for cooking rice, 20 tastes can be improved.

The alkaline water: acid water produced by electrolysis is produced at a weight ratio of about 4: 1. Since the amount of acidic water generated is small, it is sufficient to use a mixture of tap water and purified water to balance the two. The cleaning of the utensil and the drainage treatment are the same as in the second embodiment.

[0059]

According to the food processing system of the present invention, bacteria used to contaminate equipment, equipment and food used, in particular,
Heat-resistant bacteria that are difficult to heat-sterilize can be sterilized, and the freshness retention time of processed food can be extended.

Further, wastewater in food processing can be treated and recycled as washing water, so that the burden of post-processing can be reduced. Therefore, environmental pollution can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a food processing system according to a first embodiment.

FIG. 2 is an explanatory diagram of a food processing system according to a second embodiment.

FIG. 3 is an explanatory diagram of an ozone utilization system flow of the present invention.

FIG. 4 is an explanatory diagram of a food processing system according to a third embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Food washing process, 2 ... Food processing process, 1a ... Rice washing process, 2a ... Dipping process, 2b ... Rice cooking process, 3 ... Appliance washing device, 3b ... Drying process, 4 ... Ozone generator, 5 ... Wastewater oxidation treatment device , 6: Packaging process, 7: Packaging container sterilizer, 8 ...
Ozone water generator, 9: solid-liquid separator for wastewater, 10: electrolyzed water generator, 11: food, 12: processed food, 13 ...
Water, 14 ozone-containing air, 15 equipment, 16 drainage,
17 ... treated water, 18 ... rice, 19 ... packaging container, 20 ... cooked rice, 21 ... ozone water, 22 ... air or oxygen, 23 ... exhaust gas, 24 ... acidic water, 25 ... alkaline water.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kenji Baba 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd.Hitachi Research Laboratory Co., Ltd. (72) Inventor Teruji Iwata 1-chome Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture No. 6-3 Tokiko Co., Ltd. (72) Shintaro Tsujimi, inventor, 1-chome, Fujimi, Kawasaki-ku, Kawasaki, Kanagawa Prefecture No. 6-3 Tokiko Co., Ltd. Noriko Nakura, 1-6-1, Fujimi, Kawasaki-ku, Kawasaki, Kawasaki, Kanagawa No. 3 Tokiko Co., Ltd.

Claims (5)

[Claims] 1. A food processing system for cleaning and processing food, comprising: a sterilization step of sterilizing utensils, equipment and food used by using ozone-containing gas; and a step of cleaning and processing food. A wastewater oxidation treatment step of oxidizing wastewater discharged using an ozone-containing gas, wherein the ozone-containing gas used in the sterilization step of the appliance, equipment and food is supplied to the wastewater oxidation treatment step. Food processing system. 2. The food processing system according to claim 1, wherein the water obtained by treating the wastewater discharged from each of the steps in the wastewater oxidation treatment step is recycled for washing equipment or washing food. 3. The food processing system according to claim 1, wherein in each step using the ozone-containing gas, the ozone-containing gas is circulated in order from a lower steam partial pressure to a higher steam partial pressure. 4. The food processing system according to claim 1, wherein ozone water, alkaline water or acid water generated by electrolysis of water is used as water used in the washing and processing steps of the food. 5. The food processing system according to claim 1, further comprising means for separating solid-liquid wastewater discharged from each of the steps before the wastewater oxidation treatment step.