Packaging of respiring biological materials
View Patent ↗Packaging of bananas in containers, for example polyethylene bags, having designed permeabilities to oxygen, carbon dioxide, and ethylene. The bags preferably include a gas-permeable membrane comprising (1) a microporous film, and (2) a polymeric coating on the microporous film. The containers enable storage and/or ripening of bananas under controlled conditions. Using the new containers, bananas can be ripened while they are being transported, or in conventional ripening rooms without opening the containers in which they have been transported, or after they have left a ripening room. In addition, bananas can be preserved in a satisfactory ripened state for longer periods of time.
1. A sealed container which comprises
(a) at least 15 kg of bananas which have not yet reached their climacteric,
(b) a packaging atmosphere around the bananas, the packaging atmosphere containing at least 10% of oxygen and less than 10% of carbon dioxide, with the total quantity of oxygen and carbon dioxide being less than 20%, and
(c) an atmosphere control member which
(i) provides a pathway for oxygen, carbon dioxide and ethylene to enter or leave the packaging atmosphere, and
(ii) consists of a membrane which comprises a microporous film and a polymeric coating on the microporous film,
the sealed container having (i) an oxygen permeability at 13° C. per kilogram of bananas in the container (OP13/kg) of at least 700, (ii) an ethylene permeability at 13° C. per kilogram of bananas in the container (EtP13/kg) which is at least 2 times the OP13/kg, and (iii) an R ratio at 13° C. of at least 2.
2. A sealed container according to claim 1 wherein the OP13/kg is at least 1500 and the EtP13/kg is at least 3 times the OP13/kg.
3. A sealed container according to claim 1 wherein the atmosphere control member has an R ratio at 13° C. of at least 3.5.
4. A sealed container according to claim 1 wherein the packaging atmosphere contains at least 12% of oxygen and less than 10% of carbon dioxide, with the total quantity of oxygen and carbon dioxide being less than 20%.
5. A sealed container according to claim 4 wherein the packaging atmosphere contains 14-19% of oxygen and less than 4% of carbon dioxide.
6. A sealed container according to claim 5 wherein the total quantity of oxygen and carbon dioxide is less than 17%.
7. A sealed container according to claim 1 wherein the atmosphere control member has a P 10 ratio over at least one 10° C. range between 10 and 20° C. of at least 2.0.
8. A sealed container according to claim 1 wherein the membrane has an oxygen permeability (OTR), at all temperatures between 20° and 25° C., of at least 50,000 cc/100 inch 2 .atm.24 hrs.
9. A sealed container according to claim 1 wherein the membrane has an oxygen permeability (OTR), at all temperatures between 20° and 25° C., of 100,000 to 250,000 cc/100 inch 2 .atm.24 hrs.
10. A sealed container which comprises
(a) at least 15 kg of bananas which have passed their climacteric,
(b) a packaging atmosphere around the bananas, the packaging atmosphere containing 1.5 to 6% of oxygen and less than 15% of carbon dioxide, with the total quantity of oxygen and carbon dioxide being less than 16%, and
(c) an atmosphere control member which
(i) provides a pathway for oxygen, carbon dioxide and ethylene to enter or leave the packaging atmosphere, and
(ii) consists of a membrane which comprises a microporous film and a polymeric coating on the microporous film,
the sealed container having (i) an oxygen permeability at 13° C. per kilogram of bananas in the container (OP13/kg) of at least 700, (ii) an ethylene permeability at 13° C. per kilogram of bananas in the container (EtP13/kg) which is at least 2 times the OP13/kg, and (iii) an R ratio at 13° C. of at least 2.
11. A sealed container according to claim 10 wherein the packaging atmosphere contains 1.5-3% of oxygen and less than 7% of carbon dioxide.
12. A sealed container according to claim 10 wherein the bananas have been exposed to ethylene in a ripening room.
13. A sealed container according to claim 10 wherein the membrane has an oxygen permeability (OTR), at all temperatures between 20° and 25° C., of at least 50,000 cc/100 inch 2 .atm.24 hrs.
14. A sealed container according to claim 10 wherein the membrane has an oxygen permeability (OTR), at all temperatures between 20° and 25° C., of 100,000 to 250,000 cc/100 inch 2 .atm.24 hrs.
15. A sealed package which comprises a sealed container which
(a) comprises walls which are relatively impervious to gases,
(b) contains at least 15 kg of bananas which have not yet reached their climacteric and a packaging atmosphere around the bananas, the packaging atmosphere being at a temperature of 13-18° C., and
(c) at least one control section which is provided by an atmosphere control member which
(i) provides a pathway for oxygen, carbon dioxide and ethylene to enter or leave the packaging atmosphere,
(ii) consists of a membrane which comprises a microporous film and a polymeric coating on the microporous film, and which has an oxygen permeability (OTR), at all temperatures between 20° and 25° C., of at least 50,000 cc/100 inch 2 .atm.24 hrs,
(iii) extends across a complete dimension of the sealed container;
the sealing of the sealed container being a non-hermetic seal which permits equilibration of pressures inside and outside the sealed container, and the sealed container having
(i) an oxygen permeability at 13° C. per kilogram of bananas in the container (OP13/kg) of at least 700,
(ii) an ethylene permeability at 13° C. per kilogram of bananas in the container (EtP13/kg) which is at least 2 times the OP13/kg, and
(iii) an R ratio at 13° C. of at least 2.
16. A sealed container according to claim 15 wherein the OP13/kg is at least 1500 and the EtP13/kg is at least 3 times the OP13/kg.
17. A sealed container according to claim 15 wherein the atmosphere control member has an R ratio at 13° C. of at least 3.5.
18. A sealed container according to claim 15 wherein the packaging atmosphere contains at least 10% of oxygen and less than 10% of carbon dioxide, with the total quantity of oxygen and carbon dioxide being less than 20%.
19. A sealed container according to claim 18 wherein the packaging atmosphere contains 14-19% of oxygen and less than 4% of carbon dioxide, and the total quantity of oxygen and carbon dioxide is less than 17%.
20. A sealed container according to claim 15 wherein the membrane has an oxygen permeability (OTR), at all temperatures between 20° and 25° C., of 1,550,000 to 3,875,000 ml/m 2 .atm.24 hrs.
21. A sealed container according to claim 15 wherein the atmosphere control member has a P 10 ratio over at least one 10° C. range between 10 and 20° C. of at least 2.0.
22. A sealed container according to claim 15 which contains at least 1500 pounds (680 kg) of bananas.