Process and Equipment to Increase the Storage Time of Liquid Raw Food

Abstract

This invention aims to decrease the microbial load in liquid food and, at the same time, to reduce the enzyme content in said liquid, in addition to being conducted under temperatures ranging from 6° C. to 50° C. The process works in the following way: The process starts with gasifying the liquid food with pure nitrogen or a nitrogen-carbon dioxide mixture, compressing the gasified liquid to pressure between 250 bar to 500 bar, holding the pressure for at least 300 seconds, then giving an instantaneous decompression. Nitrogen with a carbon content between 1% and 10% may be used to lower the liquids' enzyme content.

Claims

1. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, to allow for an increased storage time of liquid raw food, thereby making it possible to eliminate fluctuations between supply and the continuous processing of such food, decreasing the microbial load in liquid food and, at the same time, if so desired, it further allows for reducing the enzyme content in said liquid, characterized by gasifying the liquid food and then giving an instantaneous decompression, the process being conducted under temperatures ranging from 6° C. to 50° C. and by the fact that the process comprises three sequential steps: a. the first step is to gasify the liquid food, under temperatures ranging from 6° C. and 50° C., compressing it with nitrogen, under pressures ranging from 250 bar to 500 bar, or with a nitrogen and carbon dioxide mixture at proportions varying from 1% to 10% by volume; b. the second step consists of leaving the so gasified liquid to rest in tanks, under a given pressure between 250 bar and 500 bar for at least 300-second; and c. the third step consists of pouring this liquid, now as a mist, a state that is accomplished using a 60° dispersion angle misting nozzle, onto both the central and upper portion of a cone-shaped decompression tank, with its base turned upside down; part of the gases that break free from the liquid being treated recirculate inside this tank as they are driven by a turbine that aspirates them through the upper portion of the tank in order to inject them tangentially on the vertex of the internal cone.

2. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, according to claim 1, characterized by the fact that the temperatures at which the liquids can be processed, between 6° C. and 50° C., are determined together with the compositions of the gases that will be selected for each process: a. pure nitrogen, when only the microbial load needs to be reduced, or b. nitrogen with a carbon content between 1% and 10% to lower the liquids' enzyme content in the first two steps of the process:—gasification and rest.

3. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, according to claim 1, characterized by the process is software-controlled and valves are either pneumatic or electricity-powered and the process works in the following way: a. the temperature and pressure under which the process is to be conducted, b. the hold time, and c. which gas shall be used in the process, pure nitrogen, or which nitrogen-carbon dioxide proportion shall be used will be previously defined by the software.

4. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, according to the previous claims, in its' preferred embodiment, characterized by the fact that the dosing cylinder (CD) aspirates and doses the flow of the liquid being treated, which is in the tank for liquids to be treated (T1) that flow through the valve-controlled (V1) duct (D1), up to the heat exchanger (HE); the liquid to be treated exits the heat exchanger (HE) through the duct (D2) and, controlled by the valve (V2), it is aspirated by the dosing cylinder (CD) that is driven by the driving cylinder (CA); in addition to providing the dosage, the dosing cylinder (CD) concomitantly aspirates the gases contained inside the nitrogen supply tank (T2) or in the carbon dioxide supply tank (T3), or in both of them, whose gas exhaust for the process flow through ducts (D3) and (D4), respectively, and are controlled by valves (V3) and (V4), respectively, which are connected with the gas feeding duct (D5), from which, controlled by valve (V5), the gas is supplied in a pure or mixed state, and is dosed by the aspiration cycle of the dosing cylinder (CD) that is driven by the driving cylinder (CA); therefore, the liquid to be treated and the gas to be used in the treatment—whether pure nitrogen or a mixture of nitrogen and carbon dioxide with contents ranging from 1% to 10% by volume—are aspirated and dosed by the dosing cylinder (CD) and then, upon compressing both liquid and gas, sends them through the duct (D6), controlled by valve (V6), to the gasifying compressor (CG); valves (V5) and (V7) shall be closed and valve (V6) shall be open for this operation involving sending the liquid mixture to be treated, along with the process gas, to the gasifying compressor (CG).

5. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, according to claim 4, characterized by the fact that the gasifying compressor (CG) compresses the process mixture of liquid and gas, the gasified liquid exits the gasifying compressor (CG), under the specified pressure for this operation, through the duct (D7), controlled by valve (V7), and heads for the rest tank (T4) where it is to stay for three hundred seconds; the valve (V7) must be opened, and valves (V6) and (V8) must be closed; as the time allowed for the gasified liquid to remain at rest inside the rest tank (T4) comes to an end, and as the internal pressure (T4) reaches the process pressure, valve (V8) opens up and the gasified liquid drains through the duct (D8) and then, controlled by valve (V9), they are injected by the misting nozzle (N) into the cyclone expansion vessel (VEC) in the form of mist and the misting nozzle (N) sprays the liquids in the form of a cone with a 60° opening that is placed on the vessel's central upper portion, where the operational pressure is 0.2 bar.

6. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, according to claim 4, characterized by the fact that the turbine (TU) aspirates the mist and the gases released from the liquid being treated at the cylindrical section (SC) on top of the cyclone expansion vessel (VEC), and injects them into the gases and liquids separator cyclone (C); the gases captured on top of the gases and liquids separator cyclone (C) are then forced by the turbine (TU) into the duct (D10), located right above the internal cone's (CI) vertex, tangentially to the internal wall of the internal cone (CI); from the base of the gases and liquids separator cyclone (C), the liquids that are separated from the process gases flow through duct (D13), controlled by (V13), to the processed products tank (T5); part of the liquids being processed that, due to the cyclone gases that are formed inside the cyclone expansion vessel (VEC), are thrown against the walls of the cylindrical section (SC) of said vessel, drain through the space (E) between the internal walls of the cyclone expansion vessel (VEC) and the external cone (CI), and then exit the vessel through the duct (D12) placed on the vertex of the internal walls' cone that make up the cyclone expansion vessel (VEC), and flow, through valve (V12), to the processed products tank (T5) with its refrigerator device (RE) inside.

7. “PROCESS AND EQUIPMENT TO INCREASE THE STORAGE TIME OF LIQUID RAW FOOD”, according to claim 1, characterized by the fact that the gases insufflated in the liquids being treated recirculate in the process through two circuits: a. process gases that were separated from the liquid and exited from the top of the gases and liquids cyclone separator (C) return to the base of the inner cone (CI) of the cyclone expansion vessel (VEC), powered by the turbine (TU); b. part of the gases escaping from the gasified liquids are collected at the top of the cyclone expansion vessel (VEC) and return through the vacuum pump (VP) by means of (V10) and (V11) valves, to duct (D2).

Description

[0049] Illustrations and functioning of the preferred embodiment of the invention “PROCESS AND EQUIPMENT FOR INCREASING STORAGE TIME OF LIQUID RAW FOOD” object of the present Patent.

[0050] FIG. 1 shows a schematic view depicting pieces of equipment used in the “PROCESS AND EQUIPMENT FOR INCREASING STORAGE TIME OF LIQUID RAW FOOD” (1); FIG. 1 does not show conventional pressure and temperature sensors, nor the pipes for draining and washing the equipment as these are considered standard devices used in processing liquid food and, therefore, are not part of the claims included herein; the process is software-controlled and valves are either pneumatic or electricity-powered.

[0051] FIG. 1 shows the tank for liquids to be treated (T1); the nitrogen supply tank (T2); the carbon dioxide supply tank (T3); the rest tank (T4); valves (V1), (V2), (V3), (V4), (V5), (V6), (V7), (V8), (V9), (V10), (V11), (V12) and (V13); the dosing cylinder (CD); the actuating cylinder (CA); the heat exchanger (HE); the gasification compressor (CG); the ducts (D1), (D2), (D3), (D4), (D5), (D6), (D7), (D8) e (D9), (D10), (D11), (D12) and (D13); the vacuum pump (VP); the cyclone expansion vessel (VEC), featuring its cylindrical section (SC) and its internal cone (CI); the misting nozzle (N); the turbine (TU); the gas-liquid separator cyclone (C), and the tank for finished products (T5) and its internal refrigerator device (RE).

[0052] The process works in the following way.

[0053] The following are previously defined by the software: [0054] 1—the temperature and pressure under which the process is to be conducted; [0055] 2—the hold time, and [0056] 3—which gas shall be used in the process, for example, pure nitrogen, or which nitrogen-carbon dioxide proportion shall be used.

[0057] The dosing cylinder (CD) aspirates and doses the flow of the liquid being treated, which is in the tank for liquids to be treated (T1) that flow through the valve-controlled (V1) duct (D1), up to the heat exchanger (HE) that may be used as a cooling or heating device and that will keep the liquid to be treated under the specified temperature for the process; the liquid to be treated exits the heat exchanger (HE) through the duct (D2) and, controlled by the valve (V2), it is aspirated by the dosing cylinder (CD) that is driven by the driving cylinder (CA); in addition to providing the dosage, the dosing cylinder (CD) concomitantly aspirates the gases contained inside the nitrogen supply tank (T2) or in the carbon dioxide supply tank (T3), or in both of them, whose gas exhaust for the process flow through ducts (D3) and (D4), respectively, and are controlled by valves (V3) and (V4), respectively, which are connected with the gas feeding duct (D5), from which, controlled by valve (V5), the gas is supplied in a pure or mixed state, and is dosed by the aspiration cycle of the dosing cylinder (CD) that is driven by the driving cylinder (CA); therefore, the liquid to be treated and the gas to be used in the treatment—whether pure nitrogen or a mixture of nitrogen and carbon dioxide with contents ranging from 1% to 10% by volume—are aspirated and dosed by the dosing cylinder (CD) and then, upon compressing both liquid and gas, sends them through the duct (D6), controlled by valve (V6), to the gasifying compressor (CG); valves (V5) and (V7) shall be closed and valve (V6) shall be open for this operation involving sending the liquid mixture to be treated, along with the process gas, to the gasifying compressor (CG).

[0058] The gasifying compressor (CG) is a device available in the market, and is used in liquid food homogenization; it can be a multiple stage or a single hydraulic cylinder compressor.

[0059] FIG. 1 further shows that when the gasifying compressor (CG) compresses the process mixture of liquid and gas, the gasified liquid exits the gasifying compressor (CG), under the specified pressure for this operation, through the duct (D7), controlled by valve (V7), and heads for the rest tank (T4) where it is to stay for three hundred seconds in order to complete the required time for chemical reactions to take effect aimed at reducing enzyme content; for this operation, valve (V7) must be opened, and valves (V6) and (V8) must be closed.

[0060] The rest tank's (T4) volume is calculated as a function of the capacity of the gasifying cylinder (CG) so that as the gasified liquids enter this tank it rapidly reaches the process pressure; the liquids are set to rest, under the specified pressure for the process, for as long as it has been defined.

[0061] As the time allowed for the gasified liquid to remain at rest inside the rest tank (T4) comes to an end, and as the internal pressure (T4) reaches the process pressure, valve (V8) opens up and the gasified liquid drains through the duct (D8) and then, controlled by valve (V9), they are injected by the misting nozzle (N) into the cyclone expansion vessel (VEC) in the form of mist.

[0062] The misting nozzle (N) sprays the liquids in the form of a cone with a 60° opening that is placed on the vessel's central upper portion, where the operational pressure is 0.2 bar.

[0063] The microbial load reduction of liquids being treated can happen if and only if: [0064] A—the liquid being treated is gasified under the specified pressure for each process, between 250 bar and 500 bar, by the gasifying compressor (CG), and, under such pressure, is kept inside the rest tank (T4) for as long as specified, under the temperature and pressure set forth for each liquid; [0065] B—the cyclone expansion vessel (VEC) pressure in the central and upper portion of the cyclone expansion vessel, by function of the gases-based cyclone formed therein, is under a pressure of 0.2 bar.

[0066] Only upon meeting these conditions the automatic instrumentation of the equipment allows the equipment starts the operation; valve (V9) regulates the flow of the liquid being treated that comes to the misting nozzle (N), as per instructions provided by the software; otherwise, during the course of operation of the equipment, said valve causes the liquids to diverge to the reprocessing line using a specific pipeline that, in addition to being conventional it is typically used by the liquid food industry, that being the reason why it was not included in FIG. 1 and is not part of the claims included herein.

[0067] As the process goes even further, the turbine (TU) aspirates the mist and the gases released from the liquid being treated at the cylindrical section (SC) on top of the cyclone expansion vessel (VEC), and injects them into the gases and liquids separator cyclone (C); the gases captured on top of the gases and liquids separator cyclone (C) are then forced by the turbine (TU) into the duct (D10), located right above the internal cone's (CI) vertex, tangentially to the internal wall of the internal cone (CI), thereby giving rise to the formation of an ascending cyclone of gases inside such vessel that, upon reaching the upper portion of the internal cone (CI), will make sure that the process pressure in the center of the cyclone is 0.2 bar; from the base of the gases and liquids separator cyclone (C), the liquids that are separated from the process gases flow through duct (D13), controlled by (V13), all the way to the processed products tank (T5); part of the liquids being processed that, due to the cyclone gases that are formed inside the cyclone expansion vessel (VEC), are thrown against the walls of the cylindrical section (SC) of said vessel, drain through the space (E) between the internal walls of the cyclone expansion vessel (VEC) and the external cone (CI), and then exit the vessel through the duct (D12) placed on the vertex of the walls' cone that make up the cyclone expansion vessel (VEC), and flow, through valve (V12), to the processed products tank (T5) with its refrigerator device (RE) inside.

[0068] FIG. 1 also shows that the gases insufflated in the liquids being treated recirculate in the process through two circuits: [0069] First—process gases that were separated from the liquid and exited from the top of the gases and liquids cyclone separator (C) return to the base of the inner cone (CI) of the cyclone expansion vessel (VEC), powered by the turbine (TU), to create an ascending fluid cyclone. [0070] Second—part of the gases escaping from the gasified liquids are collected at the top of the cyclone expansion vessel (VEC) and return through the vacuum pump (VP), which aspirates the gases and reinject them, by means of (V10) and (V11) valves, located in duct (D2), which is the inlet duct for the liquid being treated, and the gases follow along with these liquids into the injector cylinder (CD), thereby carrying out the recirculation of process gas applied to the gasification of the liquid being treated.

[0071] The vacuum pump (VP) is a conventional vacuum pump whose function is to reduce the volume of gas collected at the top of the expansion vessel, under low pressure, and adjust its volume to the operating conditions of the dosing cylinder (CD).

[0072] As a small part of process gases leaves the equipment in solution form with the treated liquids, replacement is handled through the software, based on simple parameters such as operating time and temperature, which acts on the gas supply valves and the dosing cylinder (CD).

[0073] The purpose of the process and equipment, object of this patent, is to increase the storage time of raw products inside the plants in order to balance the supply of raw material to the continuous production process, in which case an increase of 96 hours in the raw products' storage time will be more than sufficient.

[0074] The object of this patent was applied in laboratory tests and showed that orange juice samples treated by this process, under a temperature of 20° C. and a pressure of 250 bar, using nitrogen as a process gas with 1% carbon dioxide by volume, with a hold time of 300 seconds and maintained at 10° C. in storage containers without contact with atmospheric air, showed no signs of colony growth or formation of fermentation gases nor gelation for a period of 7 days after treatment; separation into two phases was easily reversed by mechanical agitation inside the containers. Test results indicate that higher gasification pressures of the process gases, higher temperatures, higher percentages of CO2 in the process gas with the same value of low pressure expansion, and equal amount of “hold time” will cause greater increases in storage time.