Patent Application
20220347623
This invention relates to food preservation.
Today there are literally hundreds of patents describing various method or techniques for extending the life of foods and drinks. These patents typically describe three basis techniques or combinations thereof. The intent of just about all of these devices is to reduce the amount of oxygen which makes up 21% of air to which the consumable is exposed. Of course, reducing the temperature, as in refrigeration, slows down the process of bacteria growth and extends the life span of food and drinks, but is not considered is this analysis.
The first technique involves creating a vacuum. In reality, only various degrees of a partial vacuum are created. As the vacuum level is increased (lower pressure), the amount of oxygen available to react with the food or wine is decreased and the life of the material is increased. The challenges associated with this approach are that vacuum systems are expensive, containers to sustain low pressures are expensive, and only a portion of the oxygen is removed providing limited benefits. Even with a high-level vacuum capable of reducing the pressure to 5 psi absolute (approximately one-third of atmospheric pressure), only two-thirds of the oxygen has been removed. In other words, one-third of the oxygen remains.
The second technique, and by far the most popular, is to replace air (21% oxygen) with an inert gas such as nitrogen or argon. The concept around this approach is quite simple. By replacing the air (oxygen) with these inert gases, the amount of oxidation and deterioration of the consumable, is reduced. This technique is used worldwide and does indeed result in the enhanced shelf life of food and wine. Systems that significantly reduce the level of oxygen (0.1 to 1%) have extended the shelf life of wines indefinitely while food has been extended by months. However, there are many issues associated with the technique. The use of inert gas has been found to be a cost-effective means of preserving consumables on a large-scale basis, but most homes and facilities do not have easy access to these types of gases. While there are dedicated businesses already established that bottle and distribute these gases to major consumers of the gases, this method does not lend itself to the typical user because of gas delivery issues as well as the handling of the heavy high-pressure tanks in which the gases are maintained.
Finally the third approach uses chemicals to slow the deterioration of consumables. Needless to say, this is rather risky (possibility of chemicals entering the food chain) and quite costly. Consequently, the method is rarely used beyond well controlled preservatives in food and cosmetics.
In some implementations, a system for removing oxygen from a container includes a recirculation pump and an oxygen removal device. The recirculation pump includes an intake and a discharge, and the intake includes a first connector. The discharge is fluidically connected to an oxygen removal device.
The system described offers many advantages over previous systems. First, excellent preservation performance as measured in extended shelf life/low oxygen levels is achievable. The performance can be delivered all along the food chain from the farm, through distribution, retail and ultimately home or retail use. This capability can be highly valued in both established as well as emerging markets. Secondly, there are no burdensome gas tanks that continually need to be refilled and/or transported. Thirdly, the final oxygen content of the container can be controlled with no intervention and held to very low levels. Fourthly, the cost can be reasonable. Finally, utilizing oxygen absorbing materials that allows for the discharge of the oxygen back into the environment is politically, commercially and environmentally correct, and very advantageous from a marketing and operational perspective.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
Currently, Europe frequently are placed in sealed containers just prior to being fruit ripening. In these instances, the fruit ripens using the trapped oxygen which is depleted, and the fruit then continues to be preserved for months, as long as the container is not opened thereby allowing oxygen to enter. The illustrated system 100 can store ripened fruit and then reduce or remove the oxygen slowing or preventing further ripening and spoilage.
As illustrated, the system 100 includes a circulating system 102 that extracts oxygen from air resulting in an inert gas or substantially inert gas in an atmospheric pressure environment. The circulating systems includes a circulating pump 104 that includes a canister 106 filled with oxygen reducing material (one time disposable or rechargeable multi use material) from which the oxygen reduced gas is pumped into the enclosed container 108 including, for example, food, bottled goods, clothes, or other items. The gas from the container 108 is then recirculated through the air pump 104 and the oxygen removal process is repeated for the specific container 108. The process can be repeated for other containers.
The system 100 include an oxygen reducing material, other techniques not yet known could be developed in the future and subsequently applied to the proposed system 100. These might be vacuum based or electric field based as examples.
The recirculation can provide multiple advantages. First, the oxygen removal in the container 108 will not be 100% efficient for any practical system. If only a portion of the oxygen is removed as it passes through the container 108, a lower limit of a final oxygen content in the container 108 can be set. As an example, 60% oxygen removal can result in 8% oxygen (40% of the original 20% oxygen content in air) remaining in the container 108. Even if the oxygen removal was 90%, the gas in the container 108 can still have 2% oxygen. But recycling the oxygen deprived gas exiting the container 108 can result in a continually reduced oxygen content. Table 1 is an example that demonstrates the residual oxygen after each cycle.
Even with an oxygen absorption efficiency of only 70%, the oxygen content in the container can drop below 0.6% in, for example, 3 cycles and below 0.1% in, for example, 5 cycles.
The system 100 can be closed to more efficiently use the oxygen absorbing material. When recycling the gas through the canister 108, less oxygen is typically removed with each cycle. No matter how many times the cycle is performed, the amount of oxygen removed is from the original 20% of the container 108. That said, the container 108 may have insignificant leaks that contribute additional oxygen to the system 100. To be technically accurate, due to pressure equalization (final pressure of container to be approximately atmospheric), the amount of oxygen removed can equal to about 25% of the original volume of air.
In some implementations, the oxygen removal material (ORM) can be rechargeable. In some instances, the ORM can be treated with perhaps heat or UV so that the oxygen is released and then the ORM is reused to remove oxygen again. In these instances, the recharging can occur within the system 100.
Proper controls could be implemented in order to optimize performance of the system 200. As an example, the system 200 can be set to run for a given period of time. With different size containers, the operator can select a container size or simply allow the system 200 to run for extended periods of time (e.g., minutes, hours) to most or all the oxygen.
An indirect and more cost-effective means of monitoring the oxygen level could be through the use of a pressure sensor 302. As the oxygen level is reduced, the pressure inside the closed system/container will be reduced. Monitoring this pressure reduction, as well as the rate change in pressure, allows for an accurate determination of the oxygen content. This technique would circumvent having to know the container volume or the efficiency of the oxygen absorbing material, which could change with usage.
Table 2 is listed below and lists estimates for medium quantities, and based upon the assumption that the material used to extract oxygen from the air will be rechargeable (heat or light used to discharge the oxygen).
Although the systems 100-300 has been described as standalone, it should be noted that this could be a subsystem included into other systems. As an example, today's refrigerators have enclosed storage containers to store vegetables, fruits, etc. The proposed systems 100-300 can be built into the refrigerator such that when the containers are opened and subsequently closed, the oxygen reduction recirculating system 102 would be activated either manually or by sensing the closure. As the refrigerator becomes more “intelligent”, this subsystem can be built directly into and monitored by the refrigerator.
This application claims the benefit of priority to U.S. Provisional Application No. 62/907,904, filed on Sep. 30, 2019, and also claims the benefit of priority to U.S. PCT Application No.: PCT/US2020/053592, filed on Sep. 30, 2020; the entire contents of each and together are incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2020/053592 | 9/30/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62907904 | Sep 2019 | US |
