Packaging systems for the control of relative humidity of fresh fruits, vegetables and flowers with simultaneous regulation of carbon dioxide and oxygen

Abstract

A water permeable sealed container for preservation of produce such as fruit, vegetables and flowers made out of three layer laminate corrugated to form, further three to five layer construct. The layers also include a layer of Kraft paper fluting and layer of polymer which is enclosed between two layers of Kraft paper. The container has a lid, which absorbs water vapor and transmits water vapor from the interior of the container to the exterior through micro perforations. The container can also regulate relative humidity within a range of 75% to 85% for some foods by removing moisture from the food generated from respiration and suppressing product decay due to microorganisms. The laminate may be die cut to be formed into a range of box designs for vertical profiles that provide ventilation spaces between containers in a vertical stack and to provide airflow channels within a stack.

1 . A water permeable sealed container for the preservation of fresh fruits, vegetables and flowers that consists of:
 a) A three layer water permeable laminate corrugated to form a further three to five layer construct consisting of one or two layers of kraft paper fluting and a further one or two layers of kraft paper; and   b) A water permeable lid that is sealed by a range of adhesives and/or tape to the laminate.   
     
     
         2 . A sealed container system and lid ( FIG. 1 ,  FIG. 2 ,  FIG. 3  and  FIG. 4 ) that be designed in various shapes, sizes and container designs. 
     
     
         3 . A sealed container system and lid for the preservation of fresh fruits, vegetables and/or flowers modified atmosphere package between 1% and 15% oxygen and 1% and 20%% carbon dioxide at relative humidity between 75% RH and 100% RH. 
     
     
         4 . A sealed container that includes a three layer laminate that consists of:
 a) A first layer of 150 to 250 g per m 2  kraft paper;   b) A layer 10 to 100 g per m 2  of water permeable polymer that may be constituted from a range of plastic materials including but not limited to polyamide (nylon 6, 11, 12 or 66 and blends thereof), polycarbonate, polyethylene, polyethyleneterepthalate, polypropylene, polystyrene, polyvinylchloride, and mixtures thereof;   c) A second layer of 20 to 100 g per m 2  kraft paper which effectively encloses the polymeric film between the two layers of kraft paper.   
     
     
         5 . A sealed container that is constituted from a three to five layer corrugate formed by the corrugation and adhesion of the laminate to a kraft paper flute and a further layer of kraft paper. 
     
     
         6 . A sealed container that is formed by die cutting the corrugate sheet into a range of container shapes that may include constructs shown in  FIG. 1  and  FIG. 2 . 
     
     
         7 . A sealed container that is formed from kraft paper that is either bleached or unbleached. 
     
     
         8 . A sealed container that is formed from kraft paper that consists of either virgin or recycled wood fiber. 
     
     
         9 . A sealed container that consists of a thermoformed polymeric lid that may be constituted from a range of plastic materials including but not limited to polyamide (nylon 6, 66, 11, Or 12 and blends thereof) polycarbonate, polyethylene, polyethyleneterepthalate, polypropylene, polystyrene, polyvinylchloride, and mixtures thereof. 
     
     
         10 . A sealed container that deploys several methods to provide an airtight seal between the laminate and the lid including but not limited to:
 a) A lid with friction fit compressed physical attachment to the laminate;   b) A lid with adhesive applied to the lid edges at the point of contact with the laminate of the container;   c) A lid design that is sealed to the laminate of the container with gas barrier adhesive tape.   
     
     
         11 . A sealed container that uses a laminate and lid that absorbs water vapour and transmits water vapour from the interior of the container (80% to 100% RH) to the exterior of the container (10% RH to 50% RH). 
     
     
         12 . A sealed container that contains a laminate and lid that have low permeabilities to the transfer of oxygen and carbon dioxide gas. 
     
     
         13 . A sealed container that uses a range of microperforations (60 to 90 microns in diameter) in either the container laminate and/or the lid 
     
     
         14 . A sealed container that provides a range of microperforations designed for specific package volumes, product type and respiration to provide for the following conditions:
 Category 1:   High Barrier Film:   Oxygen transmission rates of: 100 to 1500 cm 3  per m 2  per 24 hours at 25° C. at 1 atm   Carbon dioxide transmission rates of: 100 to 2000 cm 3  per m 2  per 24 hours at 25° C. at 1 atm.   Sample product applications: Baby carrots, beets and other root crops;   fresh cut salads.   Category 2:   Medium Barrier Film:   Oxygen transmission rates of: 1500 to 5000 cm 3  per m 2  per 24 hours at 25° C. at 1 atm   Carbon dioxide transmission rates of: 1500 to 7500 cm 3  per m 2  per 24 hours at 25° C. at 1 atm.   Sample product applications: Fruits such as cantaloupe, honey dew, tomatoes, apple, pears, cherries, grapes, peaches, nectarines, kiwi, strawberries, tomatoes, cucumbers (in general citrus, pome and drupe fruits, berries and greenhouse crops).   Category 3:   Low Barrier (High Permeability) Film:   Oxygen transmission rates of: 25,000+over cm 3  per m 2  per 24 hours at 25° C. at 1 atm   Carbon dioxide transmission rates of 25,000+cm 3  per m 2  per 24 hours at 25° C. at 1 atm.   Sample product applications: Mushrooms, asparagus.   
     
     
         15 . A system that can regulate relative humidity within the container within a range of 75 to 94%, preferably between 75% and 85% for some foods by removing moisture from the food and the moisture generated from respiration. The resulting relative humidity suppresses product decay due to micro-organisms. 
     
     
         16 . A system for the maintenance of fruit, vegetable and flower quality using modified atmospheres consisting of 1% to 50% carbon dioxide and 1% to 15% oxygen. 
     
     
         17 . A system that independently controls modified atmospheres and relative humidity within the container at temperatures of 0° C. to 25° C. 
     
     
         18 . A system where the sealed package of respiring produce can contain a mass ratio (grams) to total package volume (cm 3 ) of between 0.3 to 0.6. The headspace gas composition of the sealed package can be between 1% and 50% carbon dioxide and 1% to 15% oxygen with an internal relative humidity of 75% RH to 100% RH. 
     
     
         19 . A system which independently controls modified atmospheres and humidity within the container. 
     
     
         20 . A system where the three layer laminate once corrugated into a three or five layer construct may be die cut to a wide range of designs that may be further formed into a range of box designs that provide for flexible vertical profiles that provide ventilation spaces between containers in a vertical stack and to provide air flow channels within a stack, within an individual pallet and among pallets of containers constituting a trailer or storage room load.