Inference electronic shelf life dating system for perishables

PRIORITY

0001This application claims the benefit of priority to <patcit id="pcit0001" dnum="US61711340A"><text>United States provisional patent application no. 61711340, filed October 9, 2012</text></patcit> which is hereby incorporated by reference.

BACKGROUND

Field of the invention

0002The invention relates to systems and methods for inferring the shelf life or the freshness of one or more perishables when the perishables are monitored intermittently throughout their lives or when a perishable is monitored as part of a group of perishables having varying shelf lives. The invention relates to shelf life monitoring sensors and tags, the absence of shelf life monitoring sensors and tags during time periods in a perishable's life, and the perishable packaging, software, systems and processes for monitoring, inferring, estimating and analyzing the shelf life of a perishable product during the time the perishable is away from a monitoring device.

Description of the Related Art

0003Perishable products, whether produce, meats, fish, pharmaceuticals, blood, chemicals, flowers and other products, each have a unique shelf life. This shelf life is affected by the physical, chemical or biological characteristics of the perishable as well as the packaging of the perishable. Temperature is usually the predominant factor in determining shelf life-with humidity, vibration shock and other factors playing a lesser but important role.

0004For the last forty years the Use-by or Expiration date printed on a label in words and often supplemented by a barcode has been the predominant label for indicating the end time of a perishable. This date represents the perishable manufacturer's assessment of the temperature and other environmental conditions to be experienced by the perishable from the time it is manufactured until it is used. Because temperature is often different from what was predicted, the date alone is not always an accurate representation of shelf life. If a product is properly transported and stored, it can last much longer than the date. Conversely, if the temperature is higher than predicted, the product deteriorates more quickly in relation to temperature.

0005Digital shelf life monitoring labels and devices have been developed for the purpose of supplementing or replacing the paper expiration date. In reference to the use of shelf life sensors and labels to determine shelf life, <patcit id="pcit0002" dnum="US5442669A"><text>US Patent 5,442,669 (Medin</text></patcit>), <patcit id="pcit0003" dnum="US7495558B2"><text>7,495,558 B2 (Pope</text></patcit>), Patent <patcit id="pcit0004" dnum="US7764183B2"><text>7,764,183 B2 (Burchell</text></patcit>), Patent <patcit id="pcit0005" dnum="US7982622B2"><text>7,982,622 B2 (Burchell) are cited, assigned to Infratab</text></patcit>. These patents describe how electronic temperature sensors and labels are used to monitor the shelf life or freshness of a perishable using freshness determining tables in conjunction with temperature sensors to calculate shelf life used and shelf life left of a perishable.

0006<patcit id="pcit0006" dnum="US5442669A"><text>U.S. patent, 5,442,669, Medin</text></patcit>, describes a digital shelf life monitor which integrates time and temperature using a freshness determining table based upon spoilage characteristics of a perishable to calculate shelf life used and an LCD gauge for displaying shelf life left. <patcit id="pcit0007" dnum="US7495558B2"><text>U.S. patent, 7,495,558 B2, Pope et al.</text></patcit>, adds RFID to the freshness determining table and describes a tag configuration in which sensing is separate from the RFID transponder so as to enable various shapes and sizes of tag and flexibility in support of various RF frequencies. It also adds humidity, vibration and other sensors to both its freshness monitoring and to its freshness determining tables and includes methods of inheriting shelf life from a sensor tag to another sensor tag or an identification tag. <patcit id="pcit0008" dnum="US7982622B2"><text>U.S. patent, 7.982,622 B2, Burchell et al.</text></patcit>, adds the use of light and audio to identify items based upon shelf life and describes different physical configurations supported by the two module sensor architecture of the tag.

BRIEF DESCRIPTION OF THE DRAWINGS

0007The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention. The embodiments illustrated herein are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. <ul id="ul0001" list-style="none"><li><figref idref="f0001">FIG.1</figref> is a pictorial illustration of a system and methodology for monitoring the shelf life of multiple vaccine vials in a container and for inferring shelf life of the vaccine for the time period a vaccine vial is away from the container. Inference of shelf life while the vaccine is away is calculated by software in an RFID reader.</li><li><figref idref="f0002">FIG.2</figref> is a pictorial illustration of a cosmetics case comprising an inner liner designed for cosmetics wherein the identity of the item is correlated to the size and shape of a cutout or marker in the inner liner.</li><li><figref idref="f0003">FIG.3</figref> is a pictorial illustration of a system and methodology for monitoring the shelf life of fruits and vegetable packaged for and sold in a farmers market. Shelf life monitoring for different varieties of vegetables and fruits is done from pack to sale using shelf life monitoring inner liners or long tags placed below the produce and a cell phone running shelf life monitoring and inference software. A software application for a cell phone supports inference calculation by the consumer at the time of consumption.</li><li><figref idref="f0002">FIG.4</figref> is a pictorial illustration of a temperature controlled mobile transport container for bio-pharmaceuticals and other temperature sensitive products, wherein shelf life monitoring of the products inside the container is done by zone locations within the container and wherein the shelf life monitoring devices are long tags comprising antenna, power and display modules attached to the outside of the container and sensor modules for monitoring zone locations inside the container.</li><li><figref idref="f0004 f0005">FIG. 5</figref> is a flow chart illustrating a process for inferring shelf life when a product moves away from a temperature or shelf life monitoring device.</li></ul>

DETAILED DESCRIPTION OF THE INVENTION

0008The invention is based on the realization that a plurality of perishable items could be tracked individually by a single tracker by placing an ID label on each item and retaining the perishables in a container that tracks the exit and time away of item exiting from and returned to the container. The container has coupled to it a tracking device comprising the Freshness trend line data of each perishable and includes software to recalculate freshness of each item responsive to the exit from and return to the container of the item.

0009This invention addresses the systems and methods for determining the shelf life of a perishable when the cost of a shelf life label is either too expensive to monitor the perishable throughout its entire life, when there are times in the life of the perishable when temperature monitoring is not practical or when the cost of the label is affordable only when multiple perishables, each with different shelf lives, can be monitored as a group and for which the shelf life of the perishable may have to be inferred.

0010The invention comprises systems and methods for consigning multiple products of a differing nature to a temperature monitored container or space. A temperature controlled container can be as large as a cold storage room, a pre-cooler room, a silo, a reefer, a vat or a refrigerator and as small as a cooler, a vaccine dispensing container or a cosmetics case.

0011The method for inferring shelf life used when the perishable has been removed from the container is based upon shelf life characteristics of the product as known by the shelf life monitoring tag or device, the temperature when returned and the time duration away. Temperature of the perishable upon return can be measured by the reader or by the tag in the space. The inferred shelf life used while away can be calculated by either the reader or the tag. A confidence factor is calculated by either the tag or the reader, reflecting confidence in the accuracy of the temperature that was read, the assumption that this temperature was the highest temperature that was incurred, and the accuracy of the time duration since the perishable's temperature sensing and shelf life calculation when last in the container.

0012The system and methodology of inferring shelf life can be used for specific segments of a perishable's life in conjunction with more precise monitoring of temperature and shelf life in other segments of the perishable's life. The confidence factor assigned to an inferred shelf life can increase if during the time out of the container the perishable's temperature is taken. The more times the temperature is taken when away, the greater the confidence in the inferred shelf life.

0013The system herein includes a remote reading device in close proximity when the container is a refrigerator or display case or at a longer distance when the container is a corn silo, a means of monitoring the temperature of the container and the perishables in the container and away from the container and a means of calculating the shelf life of perishables that are in the container and a means of inferring the shelf life when the perishables are away. Perishables leaving or entering the container are tracked by the reader that is outside of the container. Inferred shelf life used while a perishable is away from a container can be determined in a number of ways, including by the shelf life monitoring tag when the perishable returns or by a reader outside of the container. If a perishable's shelf life metrics and last measurements were recorded into the perishable's RFID identification label when the perishable was removed from the container or were sent to a remote database, inferred shelf life during the time away can be calculated by another reader or device. A reader can be a cell phone or a reader device (RFID, NFC, infrared, magnetic, optical, wireless, Bluetooth, Zigbee). The reader can have its own means of monitoring temperature. The preferred reader for small containers is a cell phone. The preferred reader for larger containers is an RFID ultra-high frequency (UHF) or wireless reader.

0014The preferred embodiment of the invention consists of a known number of perishables, all placed into the container at the same time, monitored by a multi-sensor shelf life monitoring tag wherein each perishable has its own individual identification label. This label can be a barcode label, and RFID or NFC label, the perishable's marketing label or if a fruit or vegetable the item's price lookup code (PLU). The preferred identification label is a NFC or RFID label. This embodiment provides a base reference for the group of items and enables the shelf life monitoring tags to be set up for the package or container as a unit.

0015In accordance with this invention a system and methodology are disclosed for tracking a product which departs from a package or base temperature long enough to infer a change in the product's shelf life or to trigger an inference status of the condition of the product. Upon use or return to the container, the perishable's temperature is taken, the time away from the container is verified, an inferred shelf life is estimated, a confidence factor is recorded and if tag history is stored in a remote database, the database is updated.

0016The method includes the tracking of a known product which is removed from a shelf life monitored container and in which the product's last temperature, its shelf life left and its shelf life metrics are known or can be accessed In order to infer how much life was used during the time the perishable was not monitored. The method includes the determination of the time away, the variation in temperature from departure to return, the inference of the change in shelf life that occurred while unmonitored. The inference calculation is further refined by confidence indicator of the temperature experienced while away and by calculations as to whether the current temperature was the highest temperature encountered and by verifications by the perishable handler about the perishable's temperature exposure. The inference calculation of the shelf life used while away can be done by the shelf life monitoring tag in the container or by a reader which can take a temperature reading of the perishable.

0017Intended embodiments of the invention include a doctor's medicine cabinet or work bag, a home medicine cabinet, a vaccine vial carrying case for sensitive field uses carrying multiple disposable syringes, a smart shelf or bin, a display case for foods at a grocery store, a home refrigerator, a reefer or a silo. When the sensor or monitoring device includes RFID or optical recognition, the perishable can be tracked automatically using a barcode, RFID label or optical recognition of the departing and returning objects.

0018As part of the shelf life monitoring systems, similar to those described in <patcit id="pcit0009" dnum="US7495558B2"><text>US Patent 7,495,558 B2</text></patcit>, monitored history can be stored in the monitoring device, the reader or sent to a remote database

0019The system and method includes smart containers such as smart refrigerators, used in conjunction with remote temperature and item tracking devices, such as an RFID reader or cell phone. In this embodiment the reading device determines the identity and the temperature of departing and returning objects, tracks the time duration that the objects were in and out of the container and calculates an inferred shelf life used while in the container and while departed.

0020The invention envisions shelf life determining cases for perishables that include a readable or audible display which can signal an alert when an item in the container is about to or has reached a predefined state, such as "no longer good" or which can be used to check the shelf life when an item departs or returns to the container.

0021In certain countries, both a closed date for storage, i.e. the manufacturer's Use-by date and an "after when opened" date, might both be assigned to a perishable. The systems and methods envisioned by the invention apply to both or either date.

0022The invention envisions that within a container there are different temperature controlled compartments. In the example of a silo levels of the silo are considered zones. These zones within the container -either identified to the user in software at the reader or by identifiers within the shelf life monitoring liner for the container.

0023The invention's primary focus is on highly temperature sensitive products that are out of a monitored environment for short amounts of time (enzymes, reagents), where not having an idea of how much shelf life was used when the object was out of the monitored environment, today, results in the product being tossed rather than used. The inference system envisioned would err on the side of safety, taking into account how long a time the cooled product would take to rise to various temperatures. Included in the inference shelf life is a limit on the total time away from the controlled temperature at the highest temperature envisioned-ensuring that temperature sensitive objects are not used improperly.

0024The invention further can include additional sensors, for example, humidity, vibration, and pathogens in the system's freshness monitoring component. Wherein the freshness monitoring module receives humidity-dependent, vibration-dependent and other-sensor dependent measurement data, it determines a current freshness status based upon this data and accordingly updates the freshness status.

0025Embodiments of the invention provide for shelf life monitoring of a plurality of items in a container and for inferring shelf life used when items are removed from the container for a known period of time.

0026In accordance with the embodiments of the invention, shelf life monitoring tags or devices are either embedded into the container, are configured as removable inner liners designed for the container, or are tags placed inside of the container. The shelf life monitoring tags or devices include a communications transponder module, a sensor module containing one or more sensors for monitoring a plurality of items and environmental conditions, a power module, an optional display module, a software module and a data storage module for storing business data and tag history. The software module includes freshness determining tables for a plurality of items, inference determining modules for pausing monitored shelf life calculations and for inferring shelf life used for items which have been away and have returned to the container.

0027In the preferred embodiments of the invention individual items in the container are identified by a barcode, RFID tag or NFC identification label. The invention does support items with no serialized identification that are a part of a known and documented batchlot, have an attached printed marketing label or are used in conjunction with a container or inner liner designed for particular shapes and sizes of items, wherein these shapes can be identified as representing a specific item or item group.

0028In the preferred embodiments readers are configured with (i) shelf life monitoring software or (ii) shelf life inference software or both. Shelf life monitoring software is used to set up the shelf life monitoring tags for the container and group of items in the container, identify items placed into and removed from the container and retrieve temperature and shelf life history from the tag. Shelf life inference software is used to identify an item that is removed from and returns to the container, estimate the shelf life used during a known time duration and assign a confidence factor to the estimate. When the reader has an onboard temperature sensor, the confidence factor becomes higher the more temperature sensings that are taken while the item is away.

0029Preferred readers are RFID readers used when there are a large number of containers and NFC-enabled cell phones when a limited number of containers or items are being monitored. Other embodiments include wireless LAN, Bluetooth, Zigbee or infrared devices.

0030The preferred embodiments of the invention draw upon the calculation of shelf life as used in Infratab's shelf life monitoring tags described in <patcit id="pcit0010" dnum="US7495558B2"><text>US Patent 7,495,558 B2</text></patcit>, assigned to Infratab. As described therein, the calculation of shelf life is done based upon freshness determining tables which determine the shelf life used per sensing period. Wherein the preferred data in the tables are determined using Arrhenius kinetics, the tables support shelf life calculations that are linear, exponential or experiential.

0031The system includes in its preferred embodiment the incorporation of the methodology described in <patcit id="pcit0011" dnum="US7495558B2"><text>US Patent 7,495,558 B2</text></patcit> for representing shelf life as a percentage of life left and used calculation which defines the life of the perishable as starting at 100 and ending at 0, the use-by end of life of the perishable. The methodology for inferring shelf life used while the perishable is away from the sensor is based upon time duration the perishable has been away from the container, the temperature of the perishable at the time it leaves the container, the temperature at the time it returns to the container and a confidence factor for the inferred shelf life used calculation. The confidence factor takes into consideration time duration since the last sensing, highest temperature perishable was exposed to while away, time and temperature exposure that would cause the perishable to rise to the measured temperature and other factors.

0032Depending upon the environment of the container and how temperature is measured inside the container, the inferred shelf life used while away can be calculated by the sensing device or by reader or remote software. In accordance with <patcit id="pcit0012" dnum="US7495558B2"><text>US Patent 7,495,558 B2</text></patcit>, shelf life, temperature and time alerts can be set to notify users that the perishable is in trouble. In accordance with <patcit id="pcit0013" dnum="US7495558B2"><text>US Patent 7,495,558 B2</text></patcit>, shelf life status of the perishable can be transferred to daughter sensor, ID tags, barcodes or paper labels if appropriate.

CONTAINER--SENSOR CONFIGURATIONS

0033FIG.1a is a pictorial illustration of a system and method for monitoring the shelf life of multiple vaccine vials <b>3</b> stored in a temperature monitored container <b>1,</b> said container having an inner liner <b>2</b> comprising a shelf life monitoring device <b>9</b> configured with sensors at specified grid locations within the container. Said purpose of the shelf life monitoring device <b>9</b> is to monitor the temperature and determine shelf life used per sensing period for each of the plurality of vaccine vials, for registering vials exiting and entering the container and for inferring shelf life for vaccine vials that have left the container and returned.

0034In this embodiment each vial has an identity label <b>4.</b> This identity label can be a barcode, an RFID label or a NFC identity label. In preparation for storing vaccines in the container, a control station, comprising a computer <b>5,</b> reader <b>6</b> and shelf life monitoring software <b>7,</b> adds the shelf life freshness determining tables of the vaccine into the shelf life monitoring device <b>9.</b> When vials are placed into container <b>1,</b> shelf life monitoring software <b>7</b> registers the vaccine vials <b>3</b> that are placed into the container <b>1.</b> Data associated with setting up the shelf life monitoring device s and identifying the vials in the container 1 is sent to a remote database <b>8.</b> When container <b>1</b> is received at a location for dispensing vaccines, vaccine vial <b>13</b> is removed from container 1. At the receiving location, a control station, comprising a computer <b>11,</b> reader <b>10</b> and shelf life receiving software <b>12</b> registers vaccine vial <b>13</b> as having left the container <b>1</b>and informs the shelf life monitoring device 14. The monitoring device pauses its shelf life calculations for the vial. Shelf life receiving software <b>12</b> updates database <b>8</b> about the event. When vaccine vial 13 is returned to container 1, shelf life inference software <b>15</b> estimates how much shelf life was used when the vial was away, informs the shelf life monitoring device 14 that the vial has returned and sends data about the event to the remote database <b>8.</b> The shelf life monitoring device updates its history with inferred shelf life calculation and resumes shelf life monitoring for vial 13.

0035<figref idref="f0002">FIG.<b>2</b></figref> is a pictorial illustration of a case 21 for monitoring the shelf life of a set of cosmetics bottles or boxes <b>25,</b> said case 21 comprising a product liner <b>24</b> with a cutout or marked grid for various shapes and sizes corresponding to cosmetics bottles and boxes stored in the container and a shelf life monitoring liner <b>23</b> comprising a sensor grid corresponding to product liner 24, wherein said purpose of the shelf life monitoring liner <b>23</b> is to monitor the temperature and determine shelf life used per sensing period for each of the cosmetics in the container, for registering cosmetics exiting and entering the container and for inferring shelf life for cosmetics <b>25</b> that have left the container and returned and wherein the identity of the items are recognized by the size, shape and position of the cutouts or markers of the product inner liner <b>24.</b>

0036<figref idref="f0003">FIG.3</figref> is a pictorial illustration of a process for monitoring a container 3<b>1</b> used to store, transport and sell multiple varieties of fruits or vegetables 3<b>2</b> comprising an NFC shelf life monitoring multi-sensor inner liner 3<b>3</b>. The use case for this embodiment is a farmer who sells his products at farmers markets. Other use cases include pharmacies, fisheries, hospitals and service providers. Products are tracked by batchlot 3<b>7</b>, product variety and location of the farmers market. Shelf life monitoring begins when the items are packed in preparation of the farmers market and ends when all products are sold.

0037The farmer uses an NFC smartphone 3<b>5</b> with shelf life monitoring software application 3<b>4</b>, said application used to communicate to the shelf life monitoring inner liner <b>33</b> to set up the device with freshness determining tables for the perishables, to check status, to check out product that is sold and to save tag events in a remote database.

0038At the market the farmer uses the NFC smartphone 3<b>5</b> with a software application <b>34</b> register product sold, get alert conditions <b>43</b> of perishables, discount products with life left below a set amount and provide customers with data for use at home with shelf life inference software for consumers. A buyer having a NFC smartphone and consumer inference shelf life software <b>39</b> can connect to the remote database <b>26</b> and query data about the product purchased <b>38,</b> for the further use in a home inventory system such as a cupboard or refrigerator. At any time the consumer can measure the temperature of the known item and its packages and update its shelf life for further use by using the software application of the cell phone.

0039<figref idref="f0002">FIG.<b>4</b></figref> is a pictorial illustration of a temperature controlled mobile transport container <b>41,</b> wherein shelf life monitoring of the products inside the container is done by zone locations within the container <b>45, 46. 47</b> and wherein the shelf life monitoring devices are long tags 42 comprising antenna, power and display modules <b>43</b> attached to the outside of the container and sensor modules <b>44</b> for monitoring zone locations inside the container. Container zone temperatures are monitored, wherein the shelf life determinations for the products in the zone include a confidence factor related to product's location in the zone. In this use case the shelf life and temperature monitoring tags are designed to monitor zones that have previously been determined to have a consistency in the condition being monitored.

0040This embodiment of the invention is also applicable to non-movable large containers such as silos and vats, where monitoring of certain locations within the container is needed to determine the temperature and shelf life loss rate at various levels of the container.

0041<figref idref="f0004 f0005">FIG. <b>5</b></figref> is a flow chart illustrating a process for inferring shelf life when a product moves away from a temperature or shelf life monitoring device. When product <b>55</b> leaves the container, shelf life monitoring is stopped in the shelf life monitoring tag <b>57</b> until the item returns. The tag <b>57</b> is notified by the control station <b>51,</b> comprised of reader <b>53</b> and shelf life monitoring software <b>52</b> the item <b>55</b> is leaving the container. The tag <b>57</b> pauses shelf life monitoring and sends freshness data about the item, comprised of shelf life left, current temperature of the item, last sample time and summary of shelf life spoilage characteristics of the item. If the item has an RFID or NFC ID label <b>56</b> attached to the item, the shelf life monitoring software <b>52</b> will write the shelf life summary data supplied by the tag <b>57</b> to the ID label <b>56.</b> The shelf life monitoring software <b>52</b> will also store the data and will send the information that the item is leaving and the shelf life summary data for the item to a remote database <b>54.</b>

0042When the tagged item 55 is away, a perishable handler of the item can infer how much shelf life has been used and how much shelf life is left for the tagged item <b>55.</b> To do this the perishable handler has to have a device <b>58</b> that can read the ID label <b>56</b> of the item <b>55.</b> The preferred reader is an NFC smart phone capable of running a shelf life inference software application <b>65.</b> The perishable handler has to also have a means of taking the temperature of the perishable item <b>55.</b> The preferred system for taking the temperature is an add-on module to a cellphone which senses temperature of items in the proximity of the cellphone <b>66.</b> The shelf life inference software 65 takes the current temperature and time. Using the cell phone's NFC communications <b>66,</b> the shelf life inference software accesses the data in the ID tag <b>56,</b> calculates how much freshness has been used since the last temperature sensing, and asks the user about highest temperature the item has encountered in the time away. The more frequently that temperature of the perishable item is taken, the higher the confidence factor.

0043When the perishable item <b>55</b> is returned to its container, the shelf life inference software <b>52</b> running in control station <b>51</b> will notify the shelf life monitoring tag <b>57</b> via the reader <b>53</b> that the perishable item has returned. The tag <b>57</b> will resume its shelf life monitoring of the item. The inference software <b>52</b> will also determine if it or tag <b>57</b> will make the calculation as to shelf life used while the item <b>55</b> was away. Either the tag <b>57</b> or the inference software <b>52</b> can do this. When shelf life used and shelf life left for the perishable item is calculated, both the tag <b>57</b> and the inference software will update their history. The inference software running in the control station will also send data about the event to the remote database.

0044Specific examples of the disclosure are set out below in the following numbered clauses. <ul id="ul0002" list-style="none"><li>Clause 1 . A system for tracking the freshness state of each of a plurality of perishables in a container having an access door, comprising an ID label attached to each of said perishables, a tracking device, coupled to said container being responsive to the movement of an ID label exiting or returning to said container for updating the freshness data for the Perishable corresponding to said ID label, said tracking device comprising software operative to calculate the out of container time for a perishable.</li><li>Clause 2. A system as in clause 1 wherein said tracking device is attached to said container.</li><li>Clause 3. A system as in clause 1 wherein tracking device is remote from said container.</li><li>Clause 4. A system as in clause 1 wherein said container comprises one or more liners and comprises a tracking device in each of said liners.</li><li>Clause 5. A system as in clause 1 wherein said tracking device comprises software for determining time out of the container of an item, the changes in temperature of the item.</li><li>Clause 6. A system as in clause 4 comprising wherein the tracking device in each of said liners comprises freshness data related to the items in the associated liner.</li><li>Clause 7. A system as in clause 1 wherein said tracking device comprises a cell phone.</li><li>Clause 8. and a tracker being operative to store freshness for each of said items and/or updating said data responsive to the exit from and/or return to said container or ID label.</li><li>Clause 9. A system for tracking the freshness state of each of a plurality of perishable items in a container, said container having an access door and each of said perishable items having an ID label, said system comprising a tracking device communicatively coupled to said container operative responsive to the exiting or the returning of an ID label for updating the freshness status of the perishable corresponding to said label.</li><li>Clause 10. A method of calculating of freshness status of each of a plurality of perishable items, comprising attaching an ID label to each of said items, placing the plurality of items in a container, coupling to the container a tracking device responsive to the exiting of and the returning to the container of an item to read the ID label of the item and recalculate the freshness status of the item identified by the label.</li></ul>