Patent Application
20210163217
The present disclosure relates to containers and other packaging used to store perishable items such as harvested produce and methods of making and using thereof.
Common agricultural products, such as fresh produce, can be highly susceptible to degradation and decomposition (i.e., spoilage) when exposed to the environment. The degradation of the agricultural products can occur via abiotic means as a result of evaporative moisture loss from an external surface of the agricultural products to the atmosphere, oxidation by oxygen that diffuses into the agricultural products from the environment, mechanical damage to the surface, and/or light-induced degradation (i.e., photodegradation). Biotic stressors such as bacteria, fungi, viruses, and/or pests can also infest and decompose the agricultural products.
Harvested produce (e.g., fruits, vegetables, berries, etc.) is often stored at high density (i.e., high total volume of produce per unit volume of storage container) for extended periods of time prior to consumption, for example during shipping. During this time, the produce can be susceptible to mass loss, molding, and/or other mechanisms for spoilage if proper storage conditions are not maintained. Equipment and methods for decreasing the rate of spoilage while maintaining high quality produce, with minimal loss in mass/moisture or infestation by fungi during storage and shipping, are therefore desirable.
Described herein are packaging (e.g., containers) and methods for storing perishable items. The containers can include a plurality of openings that cause a reduction in in-package relative humidity. The perishable items can be coated with a protective coating to prevent moisture loss from produce during storage. The perishable items can be coated prior to storage in the packaging or after being placed in the packaging. The container and coatings therefore allow the perishable items to be stored at lower relative humidity (e.g., lower than industry standards for shipment and storage, or lower than about 90% relative humidity), which can help delay the growth of biotic stressors such as fungi, bacteria, viruses, and/or pests.
The protective coatings can be formed by treating the perishable items with a coating mixture that includes a coating agent dissolved or suspended in a solvent. The coating agent can include a plurality of monomers, oligomers, fatty acids, esters, amides, amines, thiols, carboxylic acids, ethers, aliphatic waxes, alcohols, salts, or combinations thereof. The coating agent can be a non-sanitizing coating agent. The solvent in which the coating agent is added to can include water and/or an alcohol. The solvent in which the coating agent is added to can include or be formed of a sanitizing agent. For example, the solvent can include ethanol, methanol, acetone, isopropanol, or ethyl acetate. Sanitizing the produce or edible product can result in a reduction in a rate of fungal growth on the produce or edible product, or in an increase in the shelf life of the produce or edible product prior to fungal growth. In some embodiments, the mixture includes a sanitizing agent such as citric acid.
Like numbers in the drawings refer to like elements.
As used herein, the term “relative humidity” (or “RH”) is defined as a ratio, expressed as a percentage, of the partial pressure of water vapor present in air to the equilibrium vapor pressure (i.e., the partial pressure of water vapor needed for saturation) at the same temperature.
As used herein, a “coating” or “protective coating” is understood to mean one or more layers of monomers, oligomers, polymers, fatty acids, esters, triglycerides, diglycerides, monoglycerides, amides, amines, thiols, thioesters, carboxylic acids, ethers, aliphatic waxes, alcohols, salts (inorganic salts or organic salts such as fatty acid salts), acids, bases, proteins, enzymes, or combinations thereof disposed over and substantially covering a surface of a perishable item such as a piece of produce.
As used herein, a “coating agent” refers to a chemical formulation that can be used to coat the surface of a substrate (e.g., after removal of a solvent in which the coating agent is dispersed) to form a coating (e.g., a protective coating) on the surface of produce. The coating agent can comprise one or more coating components. For example, the coating components can be compounds of Formula I, I-A and/or Formula I-B, or monomers or oligomers of compounds of Formula I, I-A and/or Formula I-B. Coating components can also comprise fatty acids, fatty acid esters, fatty acid amides, amines, thiols, carboxylic acids, ethers, aliphatic waxes, alcohols, salts (inorganic salts or organic salts such as fatty acid salts), or combinations thereof.
The term “alkyl” refers to a straight or branched chain saturated hydrocarbon. C1-C6 alkyl groups contain 1 to 6 carbon atoms. Examples of a C1-C6 alkyl group include, but are not limited to, methyl, ethyl, propyl, butyl, pentyl, isopropyl, isobutyl, sec-butyl and tert-butyl, isopentyl and neopentyl.
The term “alkenyl” means an aliphatic hydrocarbon group containing a carbon-carbon double bond and which may be straight or branched having about 2 to about 6 carbon atoms in the chain. Preferred alkenyl groups have 2 to about 4 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl, or propyl are attached to a linear alkenyl chain. Exemplary alkenyl groups include ethenyl, propenyl, n-butenyl, and i-butenyl. A C2-C6 alkenyl group is an alkenyl group containing between 2 and 6 carbon atoms. As defined herein, the term “alkenyl” can include both “E” and “Z” or both “cis” and “trans” double bonds.
The term “alkynyl” means an aliphatic hydrocarbon group containing a carbon-carbon triple bond and which may be straight or branched having about 2 to about 6 carbon atoms in the chain. Preferred alkynyl groups have 2 to about 4 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl, or propyl are attached to a linear alkynyl chain. Exemplary alkynyl groups include ethynyl, propynyl, n-butynyl, 2-butynyl, 3-methylbutynyl, and n-pentynyl. A C2-C6 alkynyl group is an alkynyl group containing between 2 and 6 carbon atoms.
The term “cycloalkyl” means monocyclic or polycyclic saturated carbon rings containing 3-18 carbon atoms. Examples of cycloalkyl groups include, without limitations, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptanyl, cyclooctanyl, norboranyl, norborenyl, bicyclo[2.2.2]octanyl, or bicyclo[2.2.2]octenyl. A C3-C7 cycloalkyl is a cycloalkyl group containing between 3 and 7 carbon atoms. A cycloalkyl group can be fused (e.g., decalin) or bridged (e.g., norbornane).
The term “aryl” refers to cyclic, aromatic hydrocarbon groups that have 1 to 2 aromatic rings, including monocyclic or bicyclic groups such as phenyl, biphenyl or naphthyl. Where containing two aromatic rings (bicyclic, etc.), the aromatic rings of the aryl group may be joined at a single point (e.g., biphenyl), or fused (e.g., naphthyl). The aryl group may be optionally substituted by one or more substituents, e.g., 1 to 5 substituents, at any point of attachment.
The term “heteroaryl” means a monovalent monocyclic or bicyclic aromatic ring of 5 to 12 ring atoms or a polycyclic aromatic radical, containing one or more ring heteroatoms selected from N, O, or S, the remaining ring atoms being C. Heteroaryl as herein defined also means a bicyclic heteroaromatic group wherein the heteroatom(s) is selected from N, O, or S. The aromatic ring is optionally substituted independently with one or more substituents described herein.
As used herein, the term “halo” or “halogen” means fluoro, chloro, bromo, or iodo.
As used herein, a “cationic counter ion” is any organic or inorganic positively charged ion associated with a negatively charged ion. Examples of a cationic counter ion include, for example, sodium, potassium, calcium, and magnesium. As used herein, a “cationic moiety” is any organic or inorganic positively charged ion.
The following abbreviations are used throughout. Hexadecanoic acid (i.e., palmitic acid) is abbreviated to “PA”. Octadecanoic acid (i.e., stearic acid) is abbreviated to “SA”. Tetradecanoic acid (i.e., myristic acid) is abbreviated to “MA”. (9Z)-Octadecenoic acid (i.e., oleic acid) is abbreviated to “OA”. Dodecanoic acid (e.g., lauric acid) is abbreviated to “LA”. Undecanoic acid (e.g., undecylic acid) is abbreviated to “UA”. Decanoic acid (e.g., capric acid) is abbreviated to “CA”. 1,3-dihydroxypropan-2-yl palmitate (i.e., 2-glyceryl palmitate) is abbreviated to “PA-2G”. 1,3-dihydroxypropan-2-yl octadecanoate (i.e., 2-glyceryl stearate) is abbreviated to “SA-2G”. 1,3-dihydroxypropan-2-yl tetradecanoic acid (i.e., 2-glyceryl myristate) is abbreviated to “MA-2G”. 1,3-dihydroxypropan-2-yl (9Z)-octadecenoate (i.e., 2-glyceryl oleate) is abbreviated to “OA-2G”. 2,3-dihydroxypropan-1-yl palmitate (i.e., 1-glyceryl palmitate) is abbreviated to “PA-1G”. 2,3-dihydroxypropan-1-yl octadecanoate (i.e., 1-glyceryl stearate) is abbreviated to “SA-1G”. 2,3-dihydroxypropan-1-yl tetradecanoate (i.e., 1-glyceryl myristate) is abbreviated to “MA-1G”. 2,3-dihydroxypropan-1-yl (9Z)-octadecenoate (i.e., 1-glyceryl oleate) is abbreviated to “OA-1G”. 2,3-dihydroxypropan-1-yl dodecanoate (i.e., 1-glyceryl laurate) is abbreviated to “LA-1G”. 2,3-dihydroxypropan-1-yl undecanoate (i.e., 1-glyceryl undecanoate) is abbreviated to “UA-1G”. 2,3-dihydroxypropan-1-yl decanoate (i.e., 1-glyceryl caprate) is abbreviated to “CA-1G”. Sodium salt of stearic acid is abbreviated to “SA-Na”. Sodium salt of myristic acid is abbreviated to “MA-Na”. Sodium salt of palmitic acid is abbreviated to “PA-Na”. Potassium salt of stearic acid is abbreviated to “SA-K”. Potassium salt of myristic acid is abbreviated to “MA-K”. Potassium salt of palmitic acid is abbreviated to “PA-K”. Calcium salt of stearic acid is abbreviated to “(SA)2-Ca”. Calcium salt of myristic acid is abbreviated to “(MA)2-Ca”. Calcium salt of palmitic acid is abbreviated to “(PA)2-Ca”. Magnesium salt of stearic acid is abbreviated to “(SA)2-Mg”. Magnesium salt of myristic acid is abbreviated to “(MA)2-Mg”. Magnesium salt of palmitic acid is abbreviated to “(PA)2-Mg”.
Modified Atmosphere Packaging (MAP) is commonly used for storage of perishable items such as harvested produce, for example on store shelves prior to purchase by consumers, in order to minimize degradation of the items and maintain visual, textural, and nutritional appeal of the items. Through suitable material selection and package design, MAP containers and packages can be optimized to maintain a high internal relative humidity in order to minimize the rate at which the perishable items lose mass and water over time, thereby allowing the items to be of acceptable quality when they are sold after storage and/or shipping. MAP containers and packaging can also be designed in such a way that allows the perishable items to be sufficiently cooled during storage in order to reduce the ripening rate of the items, thereby further delaying the onset of spoilage.
Table 1 below is a compilation of recommended industry standard conditions, including recommended relative humidity (RH), for long term storage of produce (e.g., fresh fruits and vegetables). As seen in Table 1, the recommended relative humidity during storage for virtually all types of common produce is at least 85%, and is typically at least 95%. The recommended storage conditions for most types of produce represents a compromise between preventing mass loss from the produce during storage and minimizing the risk of growth of postharvest pathogens. Specifically, most produce items would benefit from nearly saturated environments (e.g., an in-package relative humidity of at least 95%) in order to minimize mass loss during storage. However, such high RH levels can create environments that promote the growth of fungi and other postharvest pathogens (e.g., mold, bacteria), especially should condensation form on the surface of the produce or in any packaging within which the produce is stored, or should the produce experience damage at its surfaces due to high packing densities or handling of the produce. Furthermore, it can be difficult to precisely control the relative humidity at such high levels throughout a storage container, and so local RH variations can further exacerbate the risks of condensation formation.
Malpighia
glabra
Cucumis
metuliferus
Amaranthus
Foeniculum
Malus pumila
Prunus
Cynara
Stachys affinia
Helianthus
Eruca vesicaria
Pyrus serotina;
P. pyrifolia
Asparagus
officinalis
Annona
squamosa x A.
Persea
Carica
Musa
paradisiaca var.
Phaseolus
Vicia faba
Phaseolus
Psophocarpus
tefragonolobus
Vigna
Beta vulgaris
Rubus spp.
Vaccinium
Vaccinium
Rubus spp.
Rubus spp.
Rubus spp.
Rubus idaeus
Fragaria spp.
Momordica
charantia
Scorzonera
Brassica
Artocarpus
B. oleracea var.
Brassica
oleracea
Brassica
campesfris var.
B. oleracea
Opuntia spp.
Opuntia spp.
Averrhoa
Daucus carota
Anacardium
Manihot
esculenta
Brassica
oleracea var.
Apium
graveolens
Apium
graveolens var.
Beta vulgaris
Sechium edule
Annona
cherimola
Prunus cerasus
Prunus avium
Brassica
Allium
Citrus reticulta
x Fortunella
Citrus paradisi
Fortunella
Citrus limon
Citrus
aurantifolia;
Citrus sinensis
Citrus grandis
C. reticulata x
Cocos nucifera
B. oleracea var.
Acephala
Zea mays
Cucumis sativus
Ribes sativum;
R. nigrum; R.
Raphanus
Durio
Solanum
Cichorium
Cichorium
intybus
Feijoa, Pineapple
Feijoa
Ficus carica
Allium sativum
Zingiber
Ribes
Vitis vinifera
Vitis labrusca
Psidium
Ocimum
Allium
Coriandrum
sativum
Anethum
Chenopodium
ambrosioides
Mentha spp.
Origanum
Pefroselinum
Perilla, Shiso
Perilla
Salvia
Thymus
Myrciaria
cauliflora =
Artocarpus
Pachyrrhizus
Ziziphus jujuba
Brassica
oleracea var.
Actinidia
chinensis
Brassica
oleracea var.
Aglaia sp.;
various genera
various genera
Allium porrum
Lactuca sativa
Dimocarpus
longan
Eriobotrya
Luffa spp.
Litchi chinensis
Xanthosoma
sagittifolium
Mangifera
Garcinia
Cucurbita melo
Cucurbita melo
Cucurbita melo
Cucurbita melo
Cucurbita melo
Agaricus, other
Brassica juncea
Prunus persica
Abelmoschus
Olea europea
A llium cepa
Carica papaya
Pastinaca
Passiflora spp.
Prunus persica
Pyrus
communis
Pisum sativum
Vigna sinensis
=
Solanum
Capsicum
Capsicum
annuum and C.
Diospyros kaki
Ananas
Musa
paradisiaca var.
Prunus
Punica
Solanum
Cucurbita
Cydonia
Cichorium
Raphanus
Nephelium
Rheum
Brassica napus
Trapopogon
Chrysophyllum
Pouteria
Diospyros
Casimiroa
Calocarpum
Sapodilla,
Achras sapota
Scorzonera
A llium cepa var
ascalonicum
Annona
Spinacia
Spondias,
Spondias spp.
Medicago
Phaseolus sp.
Raphanus sp.
Cucurbita pepo
Cucurbita
moschata; C.
Ipomea batatas
Annona
squamosa;
Cyphomandra
betacea
Tamarindus
Colocasia
esculenta
Physalis
ixocarpa
Lycopersicon
Brassica
campestris var.
Eleocharis
Lepidium
sativum;
Cifrullus
Dioscorea spp.
indicates data missing or illegible when filed
As used herein, a “rigid or semi-rigid” structure is a structure that is sufficiently rigid such that its shape is not substantially modified or deformed while the structure is filled with perishable items and no other external forces are applied to the side of the structure. A mesh sack would therefore not be a rigid or semi-rigid structure, since its shape will change as it is filled with perishable items, whereas a container made of hard plastic may be rigid or semi-rigid if the plastic is sufficiently thick such that the shape of the container does not substantially change when the container is filled with perishable items.
The enclosure 102 also includes a plurality of second openings 114, where each of the second openings 114 is sufficiently small to prevent any of the perishable items that are stored in the container from being able to pass through. Accordingly, while the perishable items are stored in the container 100 with the lid 130 covering the first opening 112, the perishable items are not able to fall out of the container 100. Although
As previously described, during storage of perishable items such as harvested produce in the container 100, it may be beneficial to cool the items in order to reduce their ripening rate, thereby further delaying the onset of spoilage. Cooling of the items can be achieved via convective cooling through the plurality of second openings 114. That is, cold air or gas can be blown or otherwise taken in through the second openings 114 in order to cool the stored perishable items. In cases where the items are cooled by placing the container 100 in cold storage (e.g., in a refrigeration unit), the relative humidity within the container during cooling typically approaches that of the cold storage environment (e.g., the environment within the refrigeration unit), which can be at least 90% relative humidity.
The cooling efficiency of the stored items in container 100 is maximized by maximizing the ratio of the collective area of all of the second openings 114 to the total area of the enclosure 102 (i.e., the total area of the surface enclosing the stored items) in order to improve convective air flow through the region in which the perishable items are stored. However, after the container and the stored perishable items are removed from cold storage and placed in ambient, if the ratio of area of the openings 114 to total enclosure area is large, the relative humidity in the region containing the perishable items will decrease, as water vapor (including vapor escaping from the stored perishable items) is more easily able to escape from inside the container. This in turn causes the stored items to lose mass at a higher rate and degrade more quickly. Accordingly, in the container 100 of
If container 200 is used to store conventional perishable items such as produce that are susceptible to degradation by water/mass loss, the in-package relative humidity during storage may be lower than that recommended in Table 1, and thus the perishable items will lose mass at a higher rate and therefore degrade more quickly. For example, depending on the specific ratio of collective area of openings to total package area, the in-package relative humidity during storage may be less than 95%, less than 90%, less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, less than 20%, less than 15%, less than 10%, or less than 5%, or in a range of about 40% to about 90%, about 45% to about 90%, about 50% to about 90%, about 55% to about 90%, about 60% to about 90%, about 65% to about 90%, about 70% to about 90%, about 75% to about 90%, about 80% to about 90%, about 40% to about 85%, about 45% to about 85%, about 50% to about 85%, about 55% to about 85%, about 60% to about 85%, about 65% to about 85%, about 70% to about 85%, about 75% to about 85%, about 80% to about 85%, about 40% to about 80%, about 45% to about 80%, about 50% to about 80%, about 55% to about 80%, about 60% to about 80%, about 65% to about 80%, about 70% to about 80%, about 40% to about 75%, about 45% to about 75%, about 50% to about 75%, about 55% to about 75%, about 60% to about 75%, or about 65% to about 75% relative humidity.
While such low in-package relative humidity can have deleterious effects on many conventional perishable items, if the perishable items are coated prior to storage with a protective coating that acts as a barrier to water loss and therefore reduces the mass and/or water loss rate of the perishable items, the coated perishable items can still maintain their mass during storage and may last as long as conventional (uncoated) perishable items that are held at higher relative humidity. In fact, in many cases, the average storage lifetime of coated perishable items stored in container 200 (at lower relative humidity) is greater than that of similar perishable items (either coated or uncoated) stored at the same temperature in container 100, since the higher humidity conditions can facilitate the growth of pathogens such as mold, fungi, and bacteria, which also cause spoilage of the perishable items, particularly at high packing densities.
In some embodiments, produce or other perishable items stored in containers 100 or 200 may not be highly susceptible to degradation via water/mass loss. However, it may be desirable to minimize the respiration rate (i.e., the rate at which CO2 is produced per unit mass of the items) of the perishable items in order to reduce the ripening rate of the items in order to prolong their lifetime before spoilage. In these cases, if the perishable items are uncoated, having a smaller area of openings in the container (as in container 100) results in a lower respiration rate, since more CO2 remains trapped within the container during storage. However, for the same reasons stated earlier, the relative humidity within the container is also higher when the area of the openings is smaller, which can increase the rate of molding.
If the perishable items are coated with a protective coating that reduces the respiration rate of the items (e.g., a coating with a low permeability to CO2), then the lifetime of the items may be maximized by storage in a container with a higher area of openings (as in container 200). This is because the respiration rate of the items remains low even though the ambient concentration of CO2 in the container is lower, since the protective coating keeps the respiration rate of the items low by reducing CO2 transfer from the items to ambient. Additionally, the higher area of holes decreases the relative humidity within the container, which can decrease the rate of molding. In cases where the perishable items are not highly susceptible to degradation via water/mass loss, the low relative humidity may not substantially impact the rate of spoilage due to water/mass loss, even if the protective coating does not serve as a barrier to water/mass loss.
In view of the above, rates of spoilage of perishable items can be reduced by (a) forming a coating on the items that reduces the rate of mass loss of the items, and storing the items in a container such as container 200 that has a large area of openings; (b) forming a coating on the items that reduces the respiration rate of the items, and storing the items in a container such as container 200 that has a large area of openings; or (c) forming a coating on the items that reduces both the respiration rate and the mass loss rate of the items, and storing the items in a container such as container 200 that has a large area of openings. Furthermore, if coated perishable items stored in container 200 are cooled by placing the container 200 with the items in cold storage, the relative humidity in the cold storage environment can be set to be lower than conventional levels, for example less than less than 90%, less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, less than 20%, less than 15%, less than 10%, or less than 5%. Protective coatings that are suitable for applying to perishable items that are stored in container 200, and methods of applying the coatings, are described in more detail below.
The process steps 302, 304, 306, 308, and 310 of process 300 (
The specific composition of monomers, oligomers, polymers, fatty acids, esters, triglycerides, diglycerides, monoglycerides, amides, amines, thiols, thioesters, carboxylic acids, ethers, aliphatic waxes, alcohols, salts (inorganic salts or organic salts such as fatty acid salts), acids, bases, proteins, enzymes, or combinations thereof can be formulated such that the resulting coating formed over the perishable items (during step 306) mimics or enhances the cuticular layer of the product. The biopolyester cutin forms the main structural component of the cuticle that composes the aerial surface of most land plants. The cuticular layer is formed from a mixture of polymerized mono- and/or polyhydroxy fatty acids and esters, as well as embedded cuticular waxes. The hydroxy fatty acids and esters of the cuticle layer form tightly bound networks with high crosslink density. This crosslinked network in combination with the embedded cuticular waxes acts as a barrier to moisture loss and oxidation, as well as providing protection against other environmental stressors.
The monomers, oligomers, polymers, fatty acids, esters, triglycerides, diglycerides, monoglycerides, amides, amines, thiols, thioesters, carboxylic acids, ethers, aliphatic waxes, alcohols, salts (inorganic salts or organic salts such as fatty acid salts), acids, bases, proteins, enzymes, or combinations thereof can be extracted or derived from plant matter, and in particular from cutin obtained from plant matter. Plant matter typically includes some portions that contain cutin and/or have a high density of cutin (e.g., fruit peels, leaves, shoots, etc.), as well as other portions that do not contain cutin or have a low density of cutin (e.g., fruit flesh, seeds, etc.). The cutin-containing portions can be formed from the monomer and/or oligomer and/or polymer units that are subsequently utilized in the formulations described herein for forming the coatings over the surface of the agricultural products. The cutin-containing portions can also include other constituents such as non-hydroxylated fatty acids and esters, proteins, polysaccharides, phenols, lignans, aromatic acids, terpenoids, flavonoids, carotenoids, alkaloids, alcohols, alkanes, and aldehydes, which may be included in the formulations or may be omitted.
The monomers, oligomers, polymers, or combinations thereof can be obtained by first separating (or at least partially separating) portions of the plant that include molecules desirable for the coating agents (or molecules that can be readily modified for use in coating agents) from those that do not include the desired molecules. For example, when utilizing cutin as the feedstock for the coating agent composition, the cutin-containing portions of the plant matter are separated (or at least partially separated) from non-cutin-containing portions, and cutin is obtained from the cutin-containing portions (e.g., when the cutin-containing portion is a fruit peel, the cutin is separated from the peel). The obtained portion of the plant (e.g., cutin) is then depolymerized (or at least partially depolymerized) in order to obtain a mixture including a plurality of fatty acid or esterified cutin monomers, oligomers, polymers (e.g., low molecular weight polymers), or combinations thereof. The cutin derived monomers, oligomers, polymers, or combinations thereof can be directly dissolved or suspended in the solvent to form the solution/suspension used in the formation of the coatings, or alternatively can first be activated or chemically modified (e.g., functionalized). Chemical modification or activation can, for example, include esterifying (e.g., glycerating) the monomers, oligomers, polymers, or combinations thereof to form a mixture of 1-monoacylglycerides and/or 2-monoacylglycerides, and the mixture of 1-monoacylglycerides and/or 2-monoacylglycerides is dissolved/suspended in the solvent to form a solution/suspension, thereby resulting in the formulation formed in step 302 of
In some implementations, the coating agent includes fatty acids, esters, triglycerides, diglycerides, monoglycerides (i.e., monoacylglycerides), amides, amines, thiols, thioesters, carboxylic acids, ethers, aliphatic waxes, alcohols, salts (inorganic salts or organic salts such as fatty acid salts), acids, bases, proteins, enzymes, or combinations thereof. In some implementations, the coating agent can be substantially similar to or the same as those described in U.S. patent application Ser. No. 15/330,403 (published as US 2017/0073532) entitled “Precursor Compounds for Molecular Coatings,” filed on Sep. 15, 2016, the disclosure of which is incorporated herein by reference in its entirely. In some implementations, the coating agent can include one or more compounds of Formula I:
wherein:
R is selected from —H, -glyceryl, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl or heteroaryl is optionally substituted with one or more groups selected from halogen (e.g., Cl, BR, or I), hydroxyl, nitro, —CN, —NH2, —SH, —SR15, —OR14, —NR14R15, C1-C6 alkyl, C2-C6 alkenyl, or C2-C6 alkynyl;
R1, R2, R5, R6, R9, R10, R11, R12 and R13 are each independently, at each occurrence, —H, —(C═O)R14, —(C═O)H, —(C═O)OH, —(C═O)OR14, —(C═O)—O—(C═O)R14, —O(C═O)R14, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen;
R3, R4, R7 and R8 are each independently, at each occurrence, —H, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with —OR14, —NR14R15, —SR14, or halogen; or
R3 and R4 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or a 3- to 6-membered ring heterocycle; and/or
R7 and R8 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or a 3 to 6-membered ring heterocycle;
R14 and R15 are each independently, at each occurrence, —H, —C1-C6 alkyl, —C2-C6 alkenyl, or —C2-C6 alkynyl;
the symbol represents a single bond or a cis or trans double bond;
n is 0, 1, 2, 3, 4, 5, 6, 7, or 8;
m is 0, 1, 2, or 3;
q is 0, 1, 2, 3, 4, or 5; and
r is 0, 1, 2, 3, 4, 5, 6, 7, or 8.
In some embodiments, R is —H, —CH3, or —CH2CH3.
In some implementations, the coating agent includes monoacylglyceride (e.g., 1-monoacylglyceride or 2-monoacylglyceride) esters and/or monomers and/or oligomers and/or low molecular weight polymers formed thereof. The difference between a 1-monoacylglyceride and a 2-monoacylglyceride is the point of connection of the glycerol ester. Accordingly, in some embodiments, the coating agent includes compounds of the Formula I-A (e.g., 2-monoacylglycerides):
wherein:
each Ra is independently —H or —C1-C6 alkyl;
each Rb is independently selected from —H, —C1-C6 alkyl, or —OH;
R1, R2, R5, R6, R9, R10, R11, R12 and R13 are each independently, at each occurrence, —H, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen;
R3, R4, R7, and R8 are each independently, at each occurrence, —H, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl wherein each alkyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen; or
R3 and R4 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or 3- to 6-membered ring heterocycle; and/or
R7 and R8 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or 3- to 6-membered ring heterocycle;
R14 and R15 are each independently, at each occurrence, —H, —C1-C6 alkyl, —C2-C6 alkenyl, or —C2-C6 alkynyl;
the symbol represents a single bond or a cis or trans double bond;
n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;
m is 0, 1, 2 or 3;
q is 0, 1, 2, 3, 4 or 5; and
r is 0, 1, 2, 3, 4, 5, 6, 7 or 8.
In some implementations, the coating agent includes compounds of the Formula I-B (e.g., 1-monoacylglycerides):
wherein:
each Ra is independently —H or —C1-C6 alkyl;
each Rb is independently selected from —H, —C1-C6 alkyl, or —OH;
R1, R2, R5, R6, R9, R10, R11, R12 and R13 are each independently, at each occurrence, —H, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen;
R3, R4, R7, and R8 are each independently, at each occurrence, —H, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl wherein each alkyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen; or
R3 and R4 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or 3- to 6-membered ring heterocycle; and/or
R7 and R8 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or 3- to 6-membered ring heterocycle;
R14 and R15 are each independently, at each occurrence, —H, —C1-C6 alkyl, —C2-C6 alkenyl, or —C2-C6 alkynyl;
the symbol represents a single bond or a cis or trans double bond;
n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;
m is 0, 1, 2 or 3;
q is 0, 1, 2, 3, 4 or 5; and
r is 0, 1, 2, 3, 4, 5, 6, 7 or 8.
Any of the coating agents described herein can additionally or alternatively include fatty acid salts such as sodium salts (e.g., SA-Na, PA-Na, or MA-Na), potassium salts (e.g., SA-K, PA-K, MA-K), calcium salts (e.g., (SA)2-Ca, (PA)2-Ca, or (MA)2-Ca) or magnesium salts (e.g., (SA)2-Mg, (PA)2-Mg, or (MA)2-Mg), where. Accordingly, the coating agents herein can include one or more compounds of Formula II or Formula III, wherein Formula II and Formula III are:
wherein for each formula:
X is a cationic moiety;
Xp+ is a cationic counter ion having a charge state p, and p is 1, 2, or 3;
R1, R2, R5, R6, R9, R10, R11, R12 and R13 are each independently, at each occurrence, —H, —(C═O)R14, —(C═O)H, —(C═O)OH, —(C═O)OR14, —(C═O)—O—(C═O)R14, —O(C═O)R14, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen;
R3, R4, R7, and R8 are each independently, at each occurrence, —H, —OR14, —NR14R15, —SR14, halogen, —C1-C6 alkyl, —C2-C6 alkenyl, —C2-C6 alkynyl, —C3-C7 cycloalkyl, aryl, or heteroaryl wherein each alkyl, alkynyl, cycloalkyl, aryl, or heteroaryl is optionally substituted with one or more —OR14, —NR14R15, —SR14, or halogen; or
R3 and R4 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or 3- to 6-membered ring heterocycle; and/or
R7 and R8 can combine with the carbon atoms to which they are attached to form a C3-C6 cycloalkyl, a C4-C6 cycloalkenyl, or 3- to 6-membered ring heterocycle;
R14 and R15 are each independently, at each occurrence, —H, aryl, heteroaryl, —C1-C6 alkyl, —C2-C6 alkenyl, or —C2-C6 alkynyl;
the symbol represents a single bond or a cis or trans double bond;
n is 0, 1, 2, 3, 4, 5, 6, 7 or 8;
m is 0, 1, 2 or 3;
q is 0, 1, 2, 3, 4 or 5; and
r is 0, 1, 2, 3, 4, 5, 6, 7 or 8.
In some embodiments, the coating agent includes one or more of the following fatty acid compounds:
In some embodiments, the coating agent includes one or more of the following methyl ester compounds:
In some embodiments, the coating agent includes one or more of the following ethyl ester compounds:
In some embodiments, the coating agent includes one or more of the following 2-glyceryl ester compounds:
In some embodiments, the coating agent includes one or more of the following 1-glyceryl ester compounds:
The coating agents herein can include one or more of the following fatty acid salts (e.g., compounds of Formula II or Formula III), where X is a cationic counter ion and n represents the charge state (i.e., the number of proton-equivalent charges) of the cationic counter ion:
In some embodiments, n is 1, 2, or 3. In some embodiments, X is sodium, potassium, calcium, or magnesium.
In some embodiments, the coating agent is formed of a combination of at least 2 different compounds. For example, the coating agent can comprise a compound of Formula I-A and an additive. The additive can, for example, include a saturated or unsaturated compound of Formula I-B, a saturated or unsaturated fatty acid, an ethyl ester, or a second compound of Formula I-A which is different from the (first) compound of Formula I-A (e.g., has a different length carbon chain). The compound of Formula I-A can make up at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, or at least about 90% of the mass of the coating agent. A combined mass of the compound of Formula I-A and the additive can be at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, or at least about 90% of the total mass of the coating agent. A molar ratio of the additive to the compound of Formula I-A in the coating agent can be in a range of 0.1 to 5, for example in a range of about 0.1 to about 4, about 0.1 to about 3, about 0.1 to about 2, about 0.1 to about 1, about 0.1 to about 0.9, about 0.1 to about 0.8, about 0.1 to about 0.7, about 0.1 to about 0.6, about 0.1 to about 0.5, about 0.15 to about 5, about 0.15 to about 4, about 0.15 to about 3, about 0.15 to about 2, about 0.15 to about 1, about 0.15 to about 0.9, about 0.15 to about 0.8, about 0.15 to about 0.7, about 0.15 to about 0.6, about 0.15 to about 0.5, about 0.2 to about 5, about 0.2 to about 4, about 0.2 to about 3, about 0.2 to about 2, about 0.2 to about 1, about 0.2 to about 0.9, about 0.2 to about 0.8, about 0.2 to about 0.7, about 0.2 to about 0.6, about 0.2 to about 0.5, about 0.3 to about 5, about 0.3 to about 4, about 0.3 to about 3, about 0.3 to about 2, about 0.3 to about 1, about 0.3 to about 0.9, about 0.3 to about 0.8, about 0.3 to about 0.7, about 0.3 to about 0.6, about 0.3 to about 0.5, about 1 to about 5, about 1 to about 4, about 1 to about 3, or about 1 to about 2. The coating agent can, for example, be formed from one of the combinations of a compound of Formula I-A and an additive listed in Table 2 below.
In some embodiments, the coating agent is formed from one of the combinations of compounds listed in Table 3 below.
As seen in Table 3 above, the coating agent can include a first component and a second component, where the first component is a compound of Formula I-B and the second component is a fatty acid, a fatty acid salt, or a second compound of Formula I-B which is different than the (first) compound of Formula I-B. The compound of Formula I-B can make up at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, or at least about 90% of the mass of the coating agent. A combined mass of the first component and the second component can be at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90% or at least about 95% of the total mass of the coating agent.
Referring now to steps 304 and 306 of process 300 (
Properties of the coating, such as thickness, cross-link density of monomers/oligomers/polymers, and permeability, can be varied to be suitable for a particular agricultural product by adjusting the specific composition of the coating agent, the specific composition of the solvent, the concentration of the coating agent in the solvent, and conditions of the coating deposition process (e.g., the amount of time the solution is applied to the surface of the produce or agricultural product before the solvent is removed, the temperature during the deposition process, the standoff distance between the spray head and the sample, and the spray angle). For example, too short an application time can result in too thin a protective coating being formed, whereas too long an application time can result in the produce or agricultural product being damaged by the solvent. Accordingly, the solution/suspension can be applied to the surface of the produce or agricultural product for between about 1 and about 3,600 seconds, for example between 1 and 3000 seconds, between 1 and 2000 seconds, between 1 and 1000 seconds, between 1 and 800 seconds, between 1 and 600 seconds, between 1 and 500 seconds, between 1 and 400 seconds, between 1 and 300 seconds, between 1 and 250 seconds, between 1 and 200 seconds, between 1 and 150 seconds, between 1 and 125 seconds, between 1 and 100 seconds, between 1 and 80 seconds, between 1 and 60 seconds, between 1 and 50 seconds, between 1 and 40 seconds, between 1 and 30 seconds, between 1 and 20 seconds, between 1 and 10 seconds, between about 5 and about 3000 seconds, between about 5 and about 2000 seconds, between about 5 and about 1000 seconds, between about 5 and about 800 seconds, between about 5 and about 600 seconds, between about 5 and about 500 seconds, between about 5 and about 400 seconds, between about 5 and about 300 seconds, between about 5 and about 250 seconds, between about 5 and about 200 seconds, between about 5 and about 150 seconds, between about 5 and about 125 seconds, between about 5 and about 100 seconds, between about 5 and about 80 seconds, between about 5 and about 60 seconds, between about 5 and about 50 seconds, between about 5 and about 40 seconds, between about 5 and about 30 seconds, between about 5 and about 20 seconds, between about 5 and about 10 seconds, between about 10 and about 3000 seconds, between about 10 and about 2000 seconds, between about 10 and about 1000 seconds, between about 10 and about 800 seconds, between about 10 and about 600 seconds, between about 10 and about 500 seconds, between about 10 and about 400 seconds, between about 10 and about 300 seconds, between about 10 and about 250 seconds, between about 10 and about 200 seconds, between about 10 and about 150 seconds, between about 10 and about 125 seconds, between about 10 and about 100 seconds, between about 10 and about 80 seconds, between about 10 and about 60 seconds, between about 10 and about 50 seconds, between about 10 and about 40 seconds, between about 10 and about 30 seconds, between about 10 and about 20 seconds, between about 20 and about 100 seconds, between about 100 and about 3,000 seconds, or between about 500 and about 2,000 seconds.
Furthermore, the concentration of the coating agent in the solvent can, for example, be in a range of 0.1 to 200 mg/mL or about 0.1 to about 200 mg/mL, such as in a range of about 0.1 to about 100 mg/mL, about 0.1 to about 75 mg/mL, about 0.1 to about 50 mg/mL, about 0.1 to about 30 mg/mL, about 0.1 to about 20 mg/mL, about 0.5 to about 200 mg/mL, about 0.5 to about 100 mg/mL, about 0.5 to about 75 mg/mL, about 0.5 to about 50 mg/mL, about 0.5 to about 30 mg/mL, about 0.5 to about 20 mg/mL, 1 to 200 mg/mL, 1 to 100 mg/mL, 1 to 75 mg/mL, 1 to 50 mg/mL, 1 to 30 mg/mL, about 1 to about 20 mg/mL, about 5 to about 200 mg/mL, about 5 to about 100 mg/mL, about 5 to about 75 mg/mL, about 5 to about 50 mg/mL, about 5 to about 30 mg/mL, or about 5 to about 20 mg/mL.
The protective coatings formed from coating agents described herein can be edible coatings. The protective coatings can be substantially undetectable to the human eye, and can be odorless and/or tasteless. The protective coatings can have an average thickness in the range of about about 0.1 microns to about 300 microns, for example in the range of about about 0.5 microns to about 100 microns, about 1 micron to about 50 microns, about 0.1 microns to about 1 micron, about 0.1 microns to about 2 microns, about 0.1 microns to about 5 microns, or about 0.1 microns to about 10 microns. The protective coatings can have a thickness of less than 5 microns, less than 4 microns, less than 3 microns, less than 2 microns, less than 1 micron, less than 0.5 microns, or less than 0.3 microns. In some implementations, the protective coatings are entirely organic (e.g., organic in the agricultural sense rather than the chemistry sense). In some embodiments, the perishable items is one of the types of produce listed in Table 1. In some embodiments, the produce is a thin-skinned fruit or vegetable. For instance, the produce can be a berry or grape. In some embodiments, the produce can include a cut fruit surface (e.g., a cut apple surface).
The protective coatings formed from coating agents described herein can serve a number of purposes. For example, the protective coatings can extend the shelf life of the produce or other agricultural products, even in the absence of refrigeration. Furthermore, produce and other agricultural products tend to lose mass (due to water loss) at a higher rate when maintained at lower relative humidity (e.g., lower than 90% relative humidity) as compared to higher relative humidity, as the driving force for water evaporation is increased at the lower relative humidity. As such, the protective coatings can be formulated to reduce the mass loss rate of the produce or agricultural product even at the lower relative humidity. For example, the protective coatings can reduce the mass loss rate of the produce or other agricultural products (as compared to similar uncoated products) by at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 100%, at least 125%, at least 150%, or at least 200%. Alternatively or in addition, the protective coatings can be formulated to reduce the respiration rate (i.e., the rate at which CO2 is produced per unit mass of the items) of the produce or agricultural products. For example, the protective coatings can reduce the respiration rate of the produce or other agricultural products (as compared to similar uncoated products) by at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 100%, at least 125%, at least 150%, or at least 200%.
Referring now to step 308 of process 300 (in
Optionally, during storage, the perishable items are also cooled, for example via convection through the plurality of openings 214 in the container 200 (step 310). In some embodiments, while the perishable items are being cooled or after the perishable items have been cooled, the relative humidity in the container is less than 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, or 40%. In some embodiments, the container is configured such that during a time that the perishable items are stored in the container 200 continuously for at least 12 hours, the relative humidity in the container remains at less than 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, or 40%.
While the perishable items that are stored in container 200 can be coated prior to placing them in the container 200, in some embodiments the coatings are formed after the perishable items are placed in the container 200. For example,
Various implementations of the containers and methods of storage have been described above. However, it should be understood that they have been presented by way of example only, and not limitation. Where methods and steps described above indicate certain events occurring in certain order, those of ordinary skill in the art having the benefit of this disclosure would recognize that the ordering of certain steps may be modified and such modifications are in accordance with the variations of the disclosure. The implementations have been particularly shown and described, but it will be understood that various changes in form and details may be made. Accordingly, other implementations are within the scope of the following claims.
This application claims priority to, and the benefit of, U.S. Provisional Patent Application No. 62/717,511, filed Aug. 10, 2018, the contents of which are hereby incorporated by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2019/045784 | 8/8/2019 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62717511 | Aug 2018 | US |
