Method for ripening vegetable agricultural products in controlled atmosphere and refrigerated container, truck or trailer

Abstract

The invention relates to a method for ripening perishable agricultural products during transportation in a refrigerated container or refrigerated truck or trailer (1), each comprising a controlled atmosphere system (3), the method provides a variable ripening time by changing the temperature in the container, truck or trailer (1) from a temperature at which the ripening agricultural product is maintained in a non-ripening controlled atmosphere to a temperature at which the ripening agricultural product is ripe in a controlled atmosphere. The invention also relates to a refrigerated container or refrigerated truck or trailer (1) for shipping perishable agricultural products such as fruits and vegetables, the container, truck or trailer (1) comprising: a controlled atmosphere system (3) comprising a sensor (7) capable of measuring at least one of the following parameters: temperature, O2 or CO2; the dosing mechanism (8) is used for dosing a ripening agent; and a ripening process controller (9) that controls the ripening process based on the sensed values of temperature, O2 and / or CO2.

Description

[0001] This application is a divisional application of an invention patent application entitled "Method for ripening vegetable agricultural products in a controlled atmosphere and a refrigerated container, truck or trailer", with an international application date of November 14, 2018, an international application number of PCT / EP2018 / 081227, and a national application number of 201880074693.5.

[0002] The present invention relates to a method of ripening perishable agricultural products during transportation in a refrigerated container or a refrigerated truck or trailer, each refrigerated loading space including a controlled atmosphere system, the method providing variable ripening time.

[0003] The present invention also relates to a refrigerated container or a refrigerated truck or trailer for shipping perishable agricultural products such as fruits and vegetables, the container, truck or trailer comprising:

[0004] - A controlled atmosphere system comprising a sensor capable of measuring at least one of the following parameters: temperature, O2 or CO2.

[0005] Ripening produce is often shipped overseas via ship and refrigerated containers. Ripening produce is kept in a temperature-controlled atmosphere to prevent the produce from ripening. Over shorter distances, ripening produce can be transported in refrigerated trucks or trailers.

[0006] An example of a ripenable agricultural product could be bananas. When a shipment of bananas reaches its destination, the bananas must be ripened for a period of time in a warehouse. After the bananas have been in the ripening warehouse for a period of time, they can be distributed to markets / distribution centers at an acceptable level of ripeness.

[0007] To determine the ripening stage of bananas, a 7-stage classification of banana ripening can be used. Stage 1 is all green bananas, stage 2 is green with traces of yellow, stage 3 is more green than yellow, stage 4 is more yellow than green, stage 5 is yellow with green tips and necks, stage 6 is all yellow, and stage 7 is all yellow with brown spots. Previously, bananas would be received from ships at stage 1 (all green) and then ripened in ripening warehouses.

[0008] Another example of such ripenable produce could be avocados, plums or mangoes.

[0009] Other examples of produce that can be ripened would be fruits, vegetables. In fact, most produce that has some respiration and is suitable for a reduced respiration rate can be transported in this way.

[0010] Advantageously, therefore, the ripening process could be controlled during shipment in such a way that the produce could be distributed to distribution centers or even supermarkets in a sufficiently ripe state.

[0011] There are different solutions for controlled atmosphere and ripening of produce in containers, but what these solutions have in common is that they are inefficient and the control of the ripening process is often not thorough.

[0012] Typically, the total ratio of carbon dioxide to oxygen in the container will always remain approximately 21% unless the composition of the outgoing and / or incoming air is actively and effectively manipulated as needed to change the total ratio (21%).

[0013] A system capable of making this type of gross ratio change is a controlled atmosphere system.

[0014] The problem identified is that once the ripening process has been initiated in the container, there is limited control over the ripening process. Currently, the ripening process will be initiated by raising the temperature of the bananas to around 18°C ​​and dosing ethylene to 100 PPM into the atmosphere.

[0015] Using the banana example again, the problem with the ripening process is that once bananas begin to ripen, they give off a lot of heat. At peak ripeness, bananas can generate 300 watts per ton or more. Allowing bananas to ripen without careful controls in a container means large fans are needed to remove the heat generated by ripening and extract the heat from the container.

[0016] The degree of ripeness of bananas varies depending on the variety, ripening stage and conditions. In the ripening warehouse, bananas are manually inspected and sorted as they ripen at different rates. Current container technology does not even allow for ripening in the entire container. This means that there may be some spoiled bananas in the container even if there are other unripe bananas.

[0017] WO 95 / 00030 A1 discloses a system for ripening, for example, bananas during transport, wherein the bananas can be ripened to a stage of ripening sufficient to transport the batch of bananas directly to a retail distribution destination without the usual hold at a ripening facility. The problem of sufficient refrigeration capacity to handle the heat load generated within the container due to the ripening process is also mentioned here.

[0018] In order to avoid so-called hot spots inside containers, one solution is to ship partially filled containers, thereby providing extra space between the cargo stacks to ensure sufficient air circulation and thus reduce the temperature inside the container or keep the temperature inside the container cool.

[0019] This does not meet the desire to transport as much cargo as possible in a container.

[0020] Finally, when ripening produce in containers it is difficult to avoid the creation of hot spots in the produce and to obtain uniform ripening of the produce, and it is an object of the present invention to address this problem.

[0021] In order to be able to use controlled atmosphere to ripen produce in refrigerated containers or refrigerated trucks or trailers, it is important that the produce to be ripened is the only one in each transportable refrigerated load space or that the load has the same ripening properties. Otherwise, it is very difficult to control the ripening process by adjusting parameters such as O2, CO2, ethylene, propylene, acetylene content and temperature.

[0022] In the following, the invention is described with respect to a refrigerated container with a controlled atmosphere system, but as mentioned above, a refrigerated truck or trailer with a controlled atmosphere system may also be used. When the word "container" is used, it should be understood as a refrigerated container with a controlled atmosphere system.

[0023] One object of the present invention is to carefully control the ripening process so that ripe agricultural products can reach the market / distribution center at the ripening stage desired by the customer.

[0024] Therefore, the ripening process can be further carefully controlled by the present invention so that the ripe agricultural products reach a stage close to full maturity but not full maturity.

[0025] If the agricultural products are, for example, bananas, the aim is to have them in stage 2-3 by the time they reach the market / distribution centre. This means that the shipment of bananas can be distributed directly from the ship, truck or trailer to the market / distribution centre. In other words: by controlling the ripening process in transit, the transport time can also be used to ripen the bananas. This means that the bananas can go from shipment to market faster and directly.

[0026] The costs of ripening can thus be reduced, as the current ripening in ripening rooms and warehouses can be omitted. Each container can be individually controlled to ripen at the appropriate time. Since the produce does not have to go to a ripening warehouse, the transport routes are shorter and the overall delivery time is shortened.

[0027] Another object of the present invention is to detect when the produce to be ripened is at different stages of the CO2 generation curve and control the conditions of the container to manage the ripening of the produce. Figure 2 The ripening curve shows that the CO2 measurement is used to detect where the bananas currently being shipped are on the ripening curve.

[0028] This can be achieved by the present invention's method for ripening perishable agricultural products during transportation in a refrigerated container or a refrigerated truck or trailer, each including a controlled atmosphere system, providing variable ripening times by the steps of:

[0029] - Establishing a controlled atmosphere inside a container, truck or trailer containing ripening produce;

[0030] - changing the temperature in the container, truck or trailer from a temperature at which the ripening agricultural produce is maintained in a non-ripening controlled atmosphere to a temperature at which the ripening agricultural produce matures in a controlled atmosphere;

[0031] - dosing a ripening agent into the controlled atmosphere to initiate ripening while maintaining the controlled atmosphere;

[0032] - Check whether the ripening rate is increasing or decreasing and determine the ripening state of the produce by measuring the CO2 respiration rate;

[0033] - When the CO2 respiration rate is rising, the ripening model is calibrated using the input of the ripening start time based on the planned delivery;

[0034] - when a predetermined ripening stage is reached, changing the temperature to a temperature at which the produce can be ripened for transportation; and

[0035] -Maintaining agricultural products at a predetermined state of ripening under controlled atmosphere conditions.

[0036] The respiration rate can be expressed as a function of CO2 production. When measuring CO2 concentration, the measurement is performed inside the container by a CO2 sensor.

[0037] CO2 production in standard cubic meters per hour can be expressed as (CO2 concentration in container (CO2 %)) X (ventilation rate in standard cubic meters per hour) equals (mass of cargo / produce (bill of lading)) X (specific respiration (mlCO2 / kg / h)).

[0038] Once ripening begins, it cannot be stopped. It can be slowed down, but it cannot be stopped.

[0039] It is therefore important to initiate or start ripening when there is sufficient time to ripen the produce to a specific stage prior to delivery and to initiate or start ripening shortly before delivery so that over-ripening is avoided.

[0040] When a customer orders a batch of produce (e.g., bananas), it is determined which ripening stage a batch of bananas in a refrigerated container, refrigerated truck, or trailer should be in upon delivery. As an example, a batch in one refrigerated container may be ordered as light green bananas at a ripening stage that allows them to be stored in stores prior to sale (or sold at an early ripening stage), while another batch may be ordered at a stage where the batch consists of half green and half yellow bananas ready for sale.

[0041] Therefore, the start time of ripening based on planned delivery should be understood as the point in time during the transportation or storage of agricultural products in refrigerated containers, refrigerated trucks or trailers, where the remaining time before delivery corresponds to the ripening stage of the agricultural products to the requirements of the customer's order.

[0042] Climax-ripenable produce (e.g., bananas) picked at a given ripening stage has a given percentage of starch that can be converted to sugars during the ripening process. Final ripening is the process of activating the conversion of starch to sugars to a desired level for sale.

[0043] The conversion process requires a given amount of energy per kg of starch to be converted, which is equal to a given amount of kg CO2 produced / kg of ripenable agricultural product.

[0044] The ripening stage of bananas can be assessed based on yellowness, which is an indirect measure of the sweetness of the banana, which in turn can be expressed as the amount of starch converted into soluble sugars (glucose, fructose).

[0045] During the starch to sugar conversion process, heat (and thus CO2) is released, and there is a correlation between the starch to sugar conversion percentage and the specific cumulative CO2 production per mass unit of the ripenable agricultural product.

[0046] Taking bananas as an example, the ripeness indicator can be identified as the color of the banana. The color can be measured by one or more sensors. The ripening rate can then be expressed as the color change per time unit. The color change can then be input to adjust the O2, thereby adjusting the ripening rate.

[0047] Even if a scheduled delivery has been agreed upon, circumstances such as inclement weather may affect the delivery time. If the scheduled delivery time is changed, the ripening of the produce may be adjusted to meet the maturity for the rescheduled delivery time.

[0048] According to one embodiment of the method, the O2 content in the container is increased from a controlled atmosphere level to 5-21%, preferably to 7-10%, before the ripening agent is injected.

[0049] According to one embodiment of the method, after the injection of the ripening agent, the O2 content in the container is increased for a period of 12-48 hours.

[0050] According to one embodiment of the method, ripening is started at a predetermined time before the planned end of ripening.

[0051] The planned end of ripening is to be understood as the time in which the agricultural product has reached the determined (ordered) ripening stage.

[0052] According to one embodiment of the method, the controlled atmosphere has an O2 content of 1-10% and a CO2 content of 0-10%.

[0053] According to one embodiment of the method, the controlled atmosphere has an O2 content of 2-5% and a CO2 content of 3-7%.

[0054] According to one embodiment, the ripening stage is defined by the cumulative CO 2 production (or O 2 consumption) per mass unit of the ripenable agricultural product during the ripening process.

[0055] According to one embodiment of the method, the specific heat generation from the ripenable agricultural product is maintained below 300 watts / ton by controlling the atmosphere within the container, truck or trailer with respect to O2, CO2, ripening agent concentration and / or temperature. In another embodiment, the specific heat generation from the ripenable agricultural product is maintained below 200 watts / ton, also by controlling the atmosphere within the container, truck or trailer with respect to O2, CO2, ripening agent concentration and / or temperature.

[0056] Once ripening begins, a controlled atmosphere system in a refrigerated container, refrigerated truck or trailer can adjust the ripening rate of the produce by adjusting one or more of the following parameters: O2, CO2, ripening agent concentration and / or temperature.

[0057] According to one embodiment of the method, the ripening process is controlled based on the correlation among ripening time, temperature, O2, CO2 and ripening agent dosing.

[0058] According to one embodiment of the method, the speed of the ripening process is controlled by adjusting the O2 content in the container atmosphere to achieve a specific CO2 production or O2 consumption per mass unit of the ripenable agricultural product.

[0059] According to one embodiment of the method, the ripening stage is defined by the cumulative CO 2 production (or O 2 consumption) per mass unit of the ripenable agricultural product during the ripening process.

[0060] According to one embodiment of the method, the ripening process is calibrated by time input and a ripening correlation between the maximum respiration rate corresponding to the type of ripenable agricultural product and the ripening stage of the ripenable agricultural product in the container, truck or trailer at that time.

[0061] According to one embodiment of the method, the ripening stage is monitored using an electronic color sensor which measures color within the infrared spectrum.

[0062] According to one embodiment of the method, an electronic color sensor is used to measure the amount of chlorophyll and / or the amount of beta-carotene.

[0063] According to one embodiment of the method, the ripening process is calibrated and / or started when the measured CO2 respiration rate from the ripenable agricultural product reaches a stable signal.

[0064] To achieve a stable signal, the actual CO2 respiration rate is evaluated relative to a moving average of the CO2 respiration rate in an interval between 4 hours and 48 hours, preferably between 12 hours and 24 hours, and exceeds twice the standard deviation calculated based on CO2 respiration readings measured within the last / previous 12 hours.

[0065] When the ripening agent is injected and a stable signal of increased respiration rate is detected within the above time interval and when it exceeds twice the standard deviation, the ripening model is calibrated, where the cumulative measurement of CO2 respiration starts as an integration of a separate ripening model for determining the ripening state of one or more agricultural products.

[0066] The timing starts when the ripening agent is injected and the actual CO2 respiration rate is evaluated relative to a moving average or rolling average of the CO2 respiration rate in an interval between 4 hours and 48 hours, preferably between 12 hours and 24 hours, and a standard deviation calculated based on CO2 respiration readings measured within the last / previous 12 hours.

[0067] The ripening rate can thereby be adjusted relative to the remaining delivery time.

[0068] According to one embodiment of the method, the ripening process is adjusted based on the updated ripening end time, or the ripenable agricultural product is kept under a maintained controlled atmosphere when a predetermined ripening stage is reached.

[0069] The ripening rate can thereby be adjusted or slowed down relative to the remaining delivery time.

[0070] As an example, the ripening stage may be monitored by using an electronic color sensor that measures color within the infrared spectrum.

[0071] As an example, the color sensor may be an optical multispectral sensor that may provide information such as the amount of chlorophyll, the water content, the amount or intensity of red pigment, and the like.

[0072] In one embodiment, the amount of chlorophyll and / or the amount of beta-carotene is measured.

[0073] The measurements are used as feedback to the controller to adjust one or more of the following parameters: O2, CO2, ripening agent concentration and / or temperature.

[0074] According to one embodiment of the method, the ripening agent is ethylene and / or propylene and / or acetylene.

[0075] This may also be accomplished by the present invention with a refrigerated container or refrigerated truck or trailer for shipping perishable produce such as fruits and vegetables, the container, truck or trailer comprising:

[0076] - a controlled atmosphere system comprising a sensor capable of measuring at least one of the following parameters: temperature, O2 or CO2;

[0077] - a dosing mechanism for dosing a ripening agent; and

[0078] - A dosing process controller that controls the ripening process based on sensed values ​​of temperature, O2 and / or CO2.

[0079] The ripening process controller is a hardware CPU connected to a memory.

[0080] According to one embodiment, the controlled atmosphere system includes an electronic color sensor.

[0081] According to one embodiment, the controlled atmosphere system includes a dosing mechanism for dosing a ripening agent.

[0082] According to one embodiment, the controlled atmosphere system includes a dosing mechanism for a ripening agent receptor blocker.

[0083] An example of such a ripening agent receptor blocker may be 1-MCP.

[0084] According to one embodiment, the controlled atmosphere system includes a ripening agent removal system, which includes photocatalytic destruction, ozone destruction, or absorption removal.

[0085] According to one embodiment, the ripening agent is ethylene and / or propylene and / or acetylene.

[0086] If the controller can determine where a particular banana is on the CO2 production curve, the ripening process can be controlled. The ripening process is a multi-factor parameter process. At least CO2, O2, ethylene / propylene / acetylene and temperature all have an impact on the ripening process. Once the controller determines where the banana is on the CO2 production curve, the controller can control the atmosphere and temperature of the container so that the banana does not over-ripen and arrives at its destination at the correct ripeness according to the customer's expectations or specifications.

[0087] Specifically, the process requires 1) maintaining a stable atmosphere and temperature state in which ripening is absent, 2) initiating the ripening process by modifying / dosing the atmosphere and raising the temperature, and 3) slowing down the ripening process by lowering the temperature and modifying / purging the atmosphere.

[0088] The controller may be provided with a ripening baseline for a ripening model for, for example, a banana shipment. The ripening model may be modified based on real-time sensor input from the container. This may be necessary because the amount of O2, CO2, and ethylene, as well as the temperature generated for each different shipment and container may be different. Therefore, the ripening baseline model is calibrated for a specific banana shipment. Individual containers may be ripened according to the specific banana shipment requirements.

[0089] Therefore, each ripenable commodity will have a separate ripening model, which will be provided for each container, and the ripening baseline model can be calibrated for a specific commodity shipment. This allows individual containers to be ripened according to the requirements of the specific commodity shipment.

[0090] In the context of the present application, calibration means that when a certain CO 2 respiration rate is reached, the cumulative measurement of CO 2 respiration starts as an integration of an individual catalytic model for determining the ripening state of one or more agricultural products.

[0091] When ripenable produce is ripened in a controlled atmosphere (providing low O2 and high CO2 to slow the ripening rate), precise management of temperature within the container becomes much easier to manage.

[0092] Low O2 will correspond to an O2 content in the range of 1-10% (preferably 2-5%), and high CO2 will correspond to a CO2 content in the range of 0-10% (preferably 3-7%).

[0093] Since the controller can control the ripening speed, the process can be controlled according to the estimated arrival time of the shipment. If the shipment is delayed, the controller can delay the ripening process accordingly. The controller can be connected to a remote server. This means that the controller can receive ripening instructions remotely.

[0094] For example, if the shipper needs bananas in a more ripe state than usual due to a faster demand for ripe bananas, a ripening command is sent to the controller earlier than usual. This will mean that the bananas will be received at the final terminal in a more ripe state than normal.

[0095] The controller can modify the ripening parameters of the controlled atmosphere in the container so that the ripening time can be adjusted and hot spots in the container can be avoided.

[0096] One option for controlling ripening according to one aspect of the present invention is to determine the respiration rate and cumulative respiration of the exact produce being transported.

[0097] Each agricultural product has a specific respiration curve based on mgCO2 per kg of fruit or vegetable per hour and the elapsed time.

[0098] Such a curve is loaded into the controller and the sensed values ​​of CO2 produced by the respiration of the produce during transport are compared to the curve values ​​already present in the controller.

[0099] The value can be described as 催熟开始 Time 催熟结束 The integral of CO2 produced by the respiration of agricultural products corresponds to the CO2 generated from the time 催熟开始 Time 催熟结束 The area beneath a curve or graph.

[0100] In the event of a controller failure, the system is provided with a fail-safe mode which establishes a fail-safe atmosphere within the container.

[0101] In this case, the container atmosphere may be saturated with O2 and / or the temperature may be elevated due to a refrigeration system failure. Ethylene-blocking atmospheres may be used to control ripening. An example of a ripening agent receptor blocker may be 1-MCP.

[0102] Additionally, ethylene can be destroyed by passing the atmosphere through an ozone atmosphere or similar ethylene removal system.

[0103] Other examples of determining the ripening state of the produce may be a camera that detects color changes in the produce, one or more devices that measure the sugar content of the produce, and one or more devices that measure the hardness of the produce.

[0104] The above and other features and advantages of the present invention will become apparent to those skilled in the art through the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, in which:

[0105] Figure 1 A refrigerated container for shipping perishable produce such as fruits and vegetables is shown, the refrigerated container including equipment for establishing and maintaining a controlled atmosphere within the container;

[0106] Figure 2 shows an example of a CO2 production curve for a batch of bananas within a container including a controlled atmosphere;

[0107] Figure 3 is an example of a CO2 production curve for a batch of bananas, showing the cumulative measured CO2 respiration rate from ripenable produce in order to determine the ripening stage within a container including a controlled atmosphere;

[0108] Figure 4 A flow chart showing steps for providing a method of ripening perishable agricultural products during transportation in a refrigerated container or a refrigerated truck or trailer, each including a controlled atmosphere system, the method providing variable ripening times;

[0109] Figure 5 A flow chart showing the different ripening stages of agricultural products;

[0110] Figure 6 A flow chart illustrating signals to and from a hardware controller for controlling the process is shown; and

[0111] Figure 7 A flow chart illustrating the steps associated with the ripening model is shown.

[0112] Various embodiments are described below with reference to the accompanying drawings. Throughout the text, like reference numerals refer to like elements. Therefore, like elements will not be described in detail with respect to the description of each accompanying drawing.

[0113] It should also be noted that the drawings are only intended to facilitate the description of the embodiments.

[0114] They are not intended as an exhaustive description of the claimed invention or to limit the scope of the claimed invention. Additionally, an illustrated embodiment need not have all of the aspects or advantages illustrated.

[0115] An aspect or advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiment even if not so stated or explicitly described.

[0116] Throughout, the same reference numerals are used for the same or corresponding parts.

[0117] Figure 1 Refrigerated container 1 is shown in the figure, which has a space 2 for shipping perishable agricultural products such as fruits and vegetables. The container 1 is provided with equipment 3 for establishing and maintaining a controlled atmosphere in the container 1. Controlled atmosphere means that an atmosphere with an O2 content in the range of 1-10% (preferably 2-5%) and a CO2 content in the range of 0-10% (preferably 3-7%) is established in the container 1.

[0118] When the ripening of agricultural products begins to produce CO 2 , the controlled atmosphere system 3 can adjust the CO 2 content in the loading space 2 of the container 1 through the pressure swing adsorber or membrane 4 .

[0119] The controlled atmosphere system 3 may be provided with a pipeline 6 leading to a valve or a vacuum pump 5 .

[0120] In case the controlled atmosphere system 3 is provided with a vacuum pump 5 , CO 2 will be removed through the membrane 4 via the pipe 6 and the pump 5 to the surrounding environment.

[0121] As gas is removed from the interior of the container it is replaced by atmospheric ambient air which enters through natural gaps or slots in the container 1, for example around the door of the container or through a valve (not shown).

[0122] One objective is to identify parameters in the ripening process that serve as suitable trigger points to automate the process.

[0123] Suitable trigger points may be the O2 content and / or CO2 content in the controlled atmosphere, the temperature and / or the addition of a ripening agent.

[0124] The present invention relates to a method of ripening perishable agricultural products during transport in a refrigerated container or a refrigerated truck or trailer 1, each comprising a controlled atmosphere system 3, the method providing a variable ripening time by the following steps, the steps comprising:

[0125] - establishing a controlled atmosphere 400 in a container, truck or trailer 1 loaded with ripenable agricultural products;

[0126] - changing the temperature in the container, truck or trailer 1 from the temperature at which the ripenable agricultural product is kept in a non-ripening controlled atmosphere to the temperature at which the ripenable agricultural product ripens in a controlled atmosphere 401;

[0127] - dosing a ripening agent into the controlled atmosphere to initiate ripening while maintaining the controlled atmosphere 402;

[0128] - Check whether the ripening rate is increasing or decreasing and determine the ripening state of the agricultural product by measuring the CO2 respiration rate 403;

[0129] - When the CO2 respiration rate is rising, the ripening model 600 is calibrated 404 using an input of the ripening start time based on the planned delivery;

[0130] - when the predetermined ripening stage is reached, the temperature is changed to a transportation temperature 405 at which the agricultural products can be ripened; and

[0131] -Maintaining the agricultural product at a predetermined ripening stage under controlled atmosphere conditions 406.

[0132] Figure 4 An example of the method is shown in the flowchart of FIG.

[0133] If the agricultural product is bananas, the predetermined ripening stage may be stage 2-3, wherein stage 2 is green with traces of yellow and stage 3 is more green than yellow.

[0134] The breathing rate can be expressed as a function of CO 2 production. When measuring the CO 2 concentration, the measurement is performed inside the container 1 by means of the CO 2 sensor 7 .

[0135] CO2 production in standard cubic meters per hour can be expressed as (CO2 concentration in container 1 (CO2 %)) X (ventilation rate in standard cubic meters per hour) equals (mass of cargo / agricultural product (bill of lading)) X (specific respiration (mlCO2 / kg / h)).

[0136] The ripening rate can be checked to see if it is increasing or decreasing by measuring the increase or decrease in the CO2 respiration rate. If the ripening rate is not increasing or decreasing, the produce is stable. If an increase or decrease in the CO2 respiration rate is measured or detected, the ripening state is determined by measuring the cumulative CO2 respiration rate.

[0137] According to one embodiment of the method, the O2 content in the container 1 is increased from the controlled atmosphere level to 5-21%, preferably to 7-10%, before the ripening agent is injected.

[0138] According to one embodiment of the method, after the injection of the ripening agent, the O2 content in the container 1 is increased for a period of 12-48 hours.

[0139] According to one embodiment of the method, ripening is started at a predetermined time before the planned end of ripening.

[0140] In some cases, the planned end of ripening may coincide with the planned delivery time.

[0141] When the term "planned delivery" is used, it refers to the specific stage of ripening when the customer orders the delivery.

[0142] When the term "planned end of ripening" is used, it refers to a specific ripening stage determined by the shipping company based on planned deliveries.

[0143] In the case of transporting a refrigerated container from a ship to a terminal or warehouse, the container may be without power for a shorter or longer period of time, and if the longer period exceeds 3 hours, the advantage may be that the ripening of the agricultural products has been completed while the container is still on the ship (still connected to the power supply).

[0144] According to one embodiment of the method, the controlled atmosphere has an O2 content of 1-10% and a CO2 content of 0-10%.

[0145] According to one embodiment of the method, the controlled atmosphere has an O2 content of 2-5% and a CO2 content of 3-7%.

[0146] According to one embodiment of the method, the specific heat generation from the ripenable agricultural product is maintained below 300 W / ton by controlling the atmosphere in the container, truck or trailer 1 with respect to O2, CO2, ripening agent concentration and / or temperature. In another embodiment, the specific heat generation from the ripenable agricultural product is maintained below 200 W / ton, also by controlling the atmosphere in the container, truck or trailer 1 with respect to O2, CO2, ripening agent concentration and / or temperature.

[0147] According to one embodiment of the method, the ripening process is controlled based on the correlation among ripening time, temperature, O2, CO2 and ripening agent dosing.

[0148] According to one embodiment of the method, the speed of the ripening process is controlled by adjusting the O2 content in the container atmosphere to achieve a specific CO2 production or O2 consumption per mass unit of the ripenable agricultural product.

[0149] According to one embodiment of the method, the ripening stage is defined by the cumulative CO 2 production (or O 2 consumption) per mass unit of the ripenable agricultural product during the ripening process.

[0150] According to one embodiment of the method, the ripening process is calibrated by time input and a ripening correlation between the maximum respiration rate 21 corresponding to the type of ripenable agricultural product and the ripening stage of the ripenable agricultural product in the container, truck or trailer 1 at the time.

[0151] According to one embodiment of the method, the ripening stage is monitored using an electronic color sensor which measures color within the infrared spectrum.

[0152] According to one embodiment of the method, an electronic color sensor is used to measure the amount of chlorophyll and / or the amount of beta-carotene.

[0153] Advantageously, the ripening model 600 can be calibrated and ripening can be started under the same conditions each time with respect to the goods.

[0154] Therefore, to achieve a stable signal, the actual CO2 respiration rate is evaluated relative to a moving average of the CO2 respiration rate in an interval between 4 hours and 48 hours, preferably between 12 hours and 24 hours, and is twice the standard deviation calculated based on the CO2 respiration readings measured within the last / previous 12 hours.

[0155] When the ripening agent is injected and a stable signal of increased respiration rate is detected within the above time interval, the ripening model 600 is calibrated, where the cumulative measurement of CO2 respiration begins as an integration of the individual ripening models 600 that determine the ripening state of one or more agricultural products.

[0156] The timing is started when the ripening agent is injected and the actual CO2 respiration rate is evaluated relative to a moving average or rolling average of the CO2 respiration rate in an interval between 4 hours and 48 hours, preferably between 12 hours and 24 hours and exceeds twice the standard deviation calculated based on the readings of CO2 respiration measured within the last / previous 12 hours.

[0157] According to one embodiment of the method, the ripening process is calibrated and / or started when the cumulative measured CO2 respiration rate from the ripenable agricultural product exceeds, on average, 50% of the measurements made within the last 24 hours.

[0158] This allows the ripening stage to be determined and the ripening rate to be adjusted relative to the remaining delivery time.

[0159] According to one embodiment of the method, the ripening process is adjusted based on the updated ripening end time, or the ripenable agricultural product is kept under a maintained controlled atmosphere when a predetermined ripening stage is reached.

[0160] The ripening rate can thereby be adjusted or slowed down relative to the remaining delivery time.

[0161] To control the ripening rate, temperature is an effective parameter to control or slow down the biological processes in the ripenable produce. If the ripening rate needs to be further reduced, the amount of oxygen surrounding the ripenable produce can be reduced. This is known as CA conditions.

[0162] During ripening, the amount of O2 is more important than temperature and is therefore used as a rate control for the ripening process.

[0163] According to one embodiment of the method, the ripening agent is ethylene and / or propylene and / or acetylene.

[0164] When the agricultural products are loaded or for a period of time after the agricultural products are loaded into the refrigerated container 1, the atmosphere in the container is controlled and the agricultural products are kept under the controlled atmosphere. One or more sensors 7 measure the values ​​of CO2, O2 and / or temperature, and the values ​​are transmitted to the controller 9, which is a hardware CPU connected to a memory for controlling the ripening process. The control of the ripening process is completed by the correlation of the values ​​contained in the ripening model 600 based on the ripening baseline 601. The main control parameter for controlling the ripening process is the generation of CO2. Each specific agricultural product has a specific ripening baseline 601, from which the generation of CO2 can be determined. By storing such data in the controller 9 or in a memory communicating with the controller 9, it can be determined whether the sensed value of the generation of CO2 follows the ripening baseline 601, or whether the controlled atmosphere needs to be corrected to follow the ripening model 600 of the specific agricultural product to be ripened.

[0165] The controller communicates with the refrigerated container system and controls parameters such as CO2 atmosphere 602, O2 (e.g., through ventilation) 603, air flow 604, ripening agent dosing control 605 and / or refrigeration temperature control (heating / cooling) 606.

[0166] Thus, the controller 9 changes one or more of the parameters of the temperature and atmosphere of the container to control the position of the produce in the ripening model 600 relative to the ripening baseline 601 .

[0167] The result of the control may be, for example, increasing or decreasing O2 by introducing ambient atmosphere or by supplying O2, increasing or decreasing CO2, purging and / or adding ripening agents, and / or increasing or decreasing the temperature.

[0168] As an example, controlling ripening in a controlled atmosphere in a refrigerated container 1 can be performed as follows: when the agricultural products are in place in the refrigerated container 1 and after the refrigeration and controlled atmosphere system is started, the CO2 content in the container is monitored via the sensor 7, and when the CO2 content indicates that it is in a stable state (not rising, not falling), the ripening of the agricultural products is initiated. In the controller 9, the sensed value from the sensor 7 is used to control the ripening process under the controlled atmosphere.

[0169] When the ripening process is initiated, the temperature inside the container 1 is raised from the transport temperature to the ripening temperature and a ripening agent such as ethylene or propylene and / or acetylene is dosed into the atmosphere inside the container 1 if necessary.

[0170] The ripening process can also be initiated by dosing a ripening agent and then raising the temperature in the container 1 .

[0171] In addition, the ripening process can be initiated by simultaneously dosing the ripening agent and increasing the temperature in the container 1 .

[0172] As an example, when the produce is bananas, the transport temperature will typically be in the range between 13.5°C - 14.5°C, and the ripening temperature will be in the range between 14.5°C - 18°C.

[0173] In another example, when the produce is bananas, the transport temperature will typically be in the range between 12.5°C - 14.5°C, and the ripening temperature will be in the range between 12.5°C - 18°C.

[0174] With different varieties of bananas, lower temperatures can be used. The parameter is to obtain the lowest possible transport temperature without causing chilling damage.

[0175] As an example, when the produce is avocados, the transport temperature will typically be in the range between 7°C-13°C, and the ripening temperature will be in the range between 17°C-20°C.

[0176] As an example, when the produce is plums, the transport temperature will typically be in the range between 0°C-4°C, and the ripening temperature will be in the range between 18°C-20°C.

[0177] As an example, when the produce is mangoes, the transport temperature will typically be in the range between 10°C-14°C, and the ripening temperature will be in the range between 16°C-27°C.

[0178] The data of the relevant agricultural products are loaded into the controller 9, or the controller communicates with a memory in which the data of the agricultural products to be transported are stored. Such data are uploaded manually or automatically into the memory of the controller. When preparing a refrigerated container, truck or trailer to transport the agricultural products, the transportation and ripening data will be associated with the relevant agricultural products.

[0179] exist Figure 2 In FIG. 1 , a CO2 production curve for a batch of bananas is shown, and at 20 of the curve, the CO2 level produced is at a low, stable rate. Here, the bananas have not yet entered the ripening process. The bananas can remain in this position for a long time.

[0180] At 21, the CO2 level increases greatly and the rate of change of CO2 production is at a maximum. This is shown by the steep slope of the CO2 production curve and indicates that the ripening process has been initiated.

[0181] The ripening process may be initiated by modifying the parameters of the controlled atmosphere. Specifically, the temperature may have been increased and ripening agents introduced into the atmosphere in the container.

[0182] At 22, the CO2 production rate is at a maximum, but begins to decline. The heat generated at stage 22 is also at a maximum, up to 300 watts / ton or more.

[0183] At stage 23, the CO2 production rate is decreasing. This indicates that the bananas are suitable for delivery to a distribution center. Ideally, the bananas arrive at the dock in such a condition that they can be shipped directly to the distribution center, but the ripening stage can also accommodate situations where the bananas will be stored for a period of time before being delivered to the distribution center or will be stored for a period of time at the distribution center.

[0184] exist Figure 3 In FIG. 1 , a CO 2 production curve for a batch of bananas is also shown, and an area 24 under the curve representing the cumulative measured CO 2 respiration rate from the ripenable produce is shown to determine the ripening stage within the container 1 including the controlled atmosphere system 3 .

[0185] exist Figure 5In the embodiment of the method shown, the agricultural products are placed in a refrigerated container, and after the refrigeration and controlled atmosphere system is started and the system is operated in the normal controlled atmosphere mode 500, the CO2 content in the container is monitored 501 via the sensor 7, and when the O2 content, CO2 content and temperature are in a stable state (not rising, not falling) 502, the ripening of the agricultural products is initiated 503. Here, the ripening of the agricultural products is in stage 20. At the beginning of ripening 510, the temperature is increased 511, for example, to 18°C, and one or more ripening agents are dosed into the atmosphere 512, and the CO2 respiration rate is determined 513, after which the ripening starting point 514 is calibrated / determined. Here, the ripening of the agricultural products is in stage 21.

[0186] The ripening state is now checked 520 and the CO2 respiration rate is checked 521 relative to the ripening model, and the ripening process is controlled 522 by the controller 9 by purging / adding ripening agent 523, adjusting the CO2 / O2 balance in the controlled atmosphere 524, and adjusting the temperature 525. Next, the end of ripening is determined 526. Here, the ripening of the agricultural product is at stage 22.

[0187] Thereafter, normal controlled atmosphere mode is re-entered 530, and the temperature is adjusted / lowered 531, and the CO2 respiration rate is monitored 532. Ripening of the produce is now at stage 23.

[0188] In the controller 9, the sensed value from the sensor 7 is used to control the ripening process under the controlled atmosphere.

[0189] When the ripening process is initiated, the temperature inside the container is raised from the transport temperature to the ripening temperature and, if necessary, a ripening agent is dosed into the atmosphere inside the container.

[0190] Ripening will be initiated by introducing a ripening agent and raising the temperature relative to the transport temperature. The ripening process is calibrated and / or started when the controller detects a stable signal from the measured CO2 respiration rate of the ripenable produce.

[0191] Generally, the transport temperature can be interpreted as a temperature below the ripening temperature, and at this temperature, the ripening will be kept as low as possible.

[0192] To achieve a stable signal, the actual CO2 respiration rate is evaluated relative to a moving average of the CO2 respiration rate in an interval between 4 hours and 48 hours, preferably between 12 hours and 24 hours, and exceeds twice the standard deviation calculated based on CO2 respiration readings measured within the last / previous 12 hours.

[0193] When the ripening agent is injected and a stable signal of increased respiration rate is detected within the above time interval and when it exceeds twice the standard deviation, the ripening model is calibrated, where the cumulative measurement of CO2 respiration starts as an integration of a separate ripening model for determining the ripening state of one or more agricultural products.

[0194] The timing starts when the ripening agent is injected and the actual CO2 respiration rate is evaluated relative to a moving average or rolling average of the CO2 respiration rate in an interval between 4 hours and 48 hours, preferably between 12 hours and 24 hours, and a standard deviation calculated based on CO2 respiration readings measured within the last / previous 12 hours.

[0195] Figure 7 An implementation scheme of the ripening model is shown in the flow chart of FIG.

[0196] Here, the ripening model 600 is based on sensor input 700 from the real-time controlled atmosphere in the container, truck or trailer 1. In step 701, the sensor input is used to modify the ripening model 600 to provide an individual ripening model for a specific container, truck or trailer 1 and a specific produce cargo. The ripening model 600 is based on a conceptual ripening baseline.

[0197] In step 702, the controller 9 changes one or more of the parameters of the temperature and atmosphere of the container, truck or trailer 1 to control the position of the produce in the ripening model 600. The output from the controller 9 controls the regulation of the following steps: step 703: increase / decrease O2 by supplying / exhausting air to / from the atmosphere; step 704: increase / decrease O2; step 705: purge / add ripening agent; and step 706: increase / decrease temperature.

[0198] In one aspect, the controlled atmosphere system can be operated in an on / off mode with a set point of 5% CO2. When the system is active and the CO2 is above the set point, the system reduces the CO2 level to 5%.

[0199] On the other hand, the system may have an operating tolerance of 0.3%. This means that when the CO2 level is above the set point, the system reduces the CO2 level to 4.7% and stops. Thereafter, ambient atmosphere (comprising 21% O2) is allowed to enter the container and when 5.3% CO2 is reached, the system starts reducing the CO2 level. Thus, the system has an operating margin of 0.6% CO2.

[0200] Figure 6 An example of a controller configured to control ripening according to the method is shown.

[0201] By measuring the time to raise the CO2 content or CO2 concentration by 0.6% (without interference from the controlled atmosphere system or fresh air / ambient atmosphere supply), the number represents the value of CO2 production from the batch of agricultural products per time unit. When this value is divided by the payload of the container, the specific CO2 production per kilogram per hour is calculated.

[0202] The above calculation can be compensated with the figure / number of free volume within the container. Free volume is the space within the container that is not occupied by payload or load of agricultural products.

[0203] As an example, a standard 40-foot refrigerated container has a volume of 67m 3 , the load is 22.000 kg of bananas with a density of 1, and the free volume is 67 m 3 –22m 3 =45m 3 .

[0204] Multiplying the free volume by the CO2 production (rise in CO2 concentration) will give the CO2 production in standard cubic meters.

[0205] In another aspect, the above calculations can be calibrated by compensating for container leakage.

[0206] exist Figure 3 In the figure, a stage 25 is also indicated before the maximum production of mg CO2 per kg of fruit per hour is reached (stage 22). Here, the maximum heat production is also reached. Therefore, the purpose is to control the ripening process by adjusting the controlled atmosphere by the controller to slow down the ripening process by reducing the temperature and modifying the controlled atmosphere at stage 25 before reaching stage 22.

[0207] Thus, heat generation is kept low.One way to control / modify the atmosphere may be purging.

[0208] The example above involves bananas, but avocados, plums, mangoes or all other ripenable produce can be treated accordingly.

[0209] In order to process ripenable agricultural products according to the above method, a refrigerated container or a refrigerated truck or trailer 1 for transporting perishable agricultural products such as fruits and vegetables is provided. The container, truck or trailer 1 comprises:

[0210] - a controlled atmosphere system 3 comprising a sensor 7 capable of measuring at least one of the following parameters: temperature, O2 or CO2;

[0211] - a dosing mechanism 8, which is used to dose the ripening agent; and

[0212] - A ripening process controller 9, which controls the ripening process based on sensed values ​​of temperature, O2 and / or CO2.

[0213] Such systems are Figure 6 It is schematically shown in FIG.

[0214] According to one embodiment, the controlled atmosphere system 3 comprises an electronic color sensor.

[0215] According to one embodiment, the controlled atmosphere system 3 comprises a dosing mechanism 8 for dosing a ripening agent.

[0216] According to one embodiment, the controlled atmosphere system includes a dosing mechanism 10 for a ripening agent receptor blocker.

[0217] An example of such a ripening agent receptor blocker may be 1-MCP.

[0218] According to one embodiment, the controlled atmosphere system includes a ripening agent removal system 11, which includes photocatalytic destruction, ozone destruction, or absorption removal.

[0219] According to one embodiment, the ripening agent is ethylene and / or propylene and / or acetylene.

[0220] Although specific features have been shown and described, it should be understood that they are not intended to limit the claimed invention, and it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the claimed invention. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.

[0221] The claimed invention is intended to embrace all alternatives, modifications, and equivalents.

Claims

1. A method of ripening perishable agricultural products during transportation in a refrigerated container or a refrigerated truck or trailer (1), each of which includes a controlled atmosphere system (3), the method providing a variable ripening time by the following steps, the steps comprising: - establishing a controlled atmosphere (400) in the container, truck or trailer (1) loaded with ripenable agricultural products, the controlled atmosphere having an O2 content of 1-10% and a CO2 content of 0-10%; - Obtaining the ripening start time based on the planned delivery of ripenable agricultural products; - maintaining the ripenable agricultural product in the controlled atmosphere until the ripening starts; - changing the temperature in the container, truck or trailer (1) from a temperature at which the ripenable agricultural product is maintained in a non-ripening controlled atmosphere to a temperature at which the ripenable agricultural product is ripened in a controlled atmosphere (401); - dosing a ripening agent into the controlled atmosphere to initiate ripening while maintaining the controlled atmosphere (402); - checking whether the ripening rate is increasing or decreasing and determining the ripening state of the ripenable agricultural product by measuring the CO2 respiration rate (403); - When the CO2 respiration rate is rising, calibrating (404) the ripening model (600) using an input of the ripening start time based on the planned delivery; - when a predetermined ripening stage is reached, changing the temperature in the refrigerated container or refrigerated truck or trailer to the transport temperature of the ripenable agricultural product (405); and - maintaining the ripenable agricultural product at a predetermined ripening stage under controlled atmosphere conditions (406), The ripening stage is defined by the cumulative CO2 production or O2 consumption per unit mass of ripenable agricultural product during the ripening process.

2. The method according to claim 1, characterized in that Prior to injecting the ripening agent, the O2 content in the container (1) is increased from a controlled atmosphere level to 5-21%.

3. The method according to claim 1 or 2, characterized in that: Prior to injecting the ripening agent, the O2 content in the container (1) is increased from a controlled atmosphere level to 7-10%.

4. The method according to claim 2, characterized in that: After injection of the ripening agent, the O2 content in the container (1) is increased for a period of 12-48 hours.

5. The method according to claim 1 or 2, characterized in that: Ripening begins at a predetermined time before the planned end of ripening.

6. The method according to claim 1 or 2, characterized in that: The controlled atmosphere has an O2 content of 2-5% and a CO2 content of 3-7%.

7. The method according to claim 1 or 2 further comprises maintaining the specific heat generation from the ripenable agricultural product below 300 W / ton by controlling the atmosphere within the container, truck or trailer (1) in relation to O2, CO2, ripening agent concentration and / or temperature.

8. The method according to claim 1 or 2, characterized in that: The ripening process is controlled based on the correlation among ripening time, temperature, O2, CO2 and ripening agent dosage.

9. The method according to claim 1 or 2, characterized in that: The ripening rate is controlled by adjusting the O2 content within the container atmosphere to achieve a specific CO2 production or O2 consumption per unit mass of ripenable produce.

10. The method according to claim 1 or 2, characterized in that: The ripening process is calibrated by the following: the input at a certain time and the ripening correlation between the maximum respiration rate corresponding to the type of ripenable agricultural product at that time and the ripening stage of the ripenable agricultural product in the container, truck or trailer (1).

11. The method according to claim 1 or 2, characterized in that: The ripening stage is monitored using an electronic color sensor that measures color within the infrared spectrum.

12. The method according to claim 1 or 2, characterized in that: An electronic color sensor is used to measure the amount of chlorophyll and / or the amount of beta-carotene.

13. The method according to claim 1 or 2, characterized in that: The ripening process is calibrated and / or started when the actual CO2 respiration rate is evaluated relative to a moving average or rolling average of the CO2 respiration rate in an interval between 4 hours and 48 hours and exceeds twice the standard deviation calculated based on readings of CO2 respiration measured within the last / previous 12 hours.

14. The method according to claim 13, characterized in that The ripening process is calibrated and / or started when the actual CO2 respiration rate is evaluated relative to a moving average or rolling average of the CO2 respiration rate in an interval between 12 hours and 24 hours and exceeds twice the standard deviation calculated based on readings of CO2 respiration measured within the last / previous 12 hours.

15. The method according to claim 1 or 2, characterized in that: The ripening process is adjusted based on the updated ripening end time, or the ripenable agricultural product is kept under a maintained controlled atmosphere when a predetermined ripening stage is reached.

16. The method according to claim 1 or 2, characterized in that: The ripening agent is ethylene and / or propylene and / or acetylene.

17. A refrigerated container or a refrigerated truck or trailer (1) for transporting perishable agricultural products, the container, truck or trailer (1) comprising: - a controlled atmosphere system (3) comprising a sensor (7) capable of measuring at least one of the following parameters: temperature, O2 or CO2, wherein the controlled atmosphere in the container, truck or trailer has an O2 content of 1-10% and a CO2 content of 0-10%; - a dosing mechanism (8) for dosing a ripening agent; and - a dosing process controller (9), which controls the ripening process based on sensed values ​​of temperature, O2 and / or CO2, and which is configured to perform the method of claim 1.

18. A refrigerated container or refrigerated truck or trailer (1) according to claim 17, wherein the perishable agricultural products are fruits or vegetables.

19. A refrigerated container or a refrigerated truck or trailer (1) according to claim 17, characterised in that Includes electronic color sensor.

20. A refrigerated container or a refrigerated truck or trailer (1) according to claim 17 or 18, characterised in that The controlled atmosphere system (3) comprises a dosing mechanism (8) for dosing a ripening agent.

21. A refrigerated container or a refrigerated truck or trailer (1) according to claim 17 or 18, characterised in that The controlled atmosphere system (3) comprises a dosing mechanism (10) for a ripening agent receptor blocker.

22. A refrigerated container or a refrigerated truck or trailer (1) according to claim 17 or 18, characterised in that The controlled atmosphere system (3) comprises a ripening agent removal system (11), wherein the ripening agent removal system comprises photocatalytic destruction, ozone destruction or absorption removal.

23. A refrigerated container, refrigerated truck or trailer (1) according to claim 17 or 18, characterised in that: The ripening agent is ethylene and / or propylene and / or acetylene.

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