Treatment for protecting agricultural products from tiger disease and / or scratch damage

Abstract

A thixotropic aqueous mixture for preventing tiger disease and / or scratch damage in agricultural products, such as fruit or kernel fruit, comprising at least one smectite clay and a water-soluble polymer wherein the thixotropic aqueous mixture is added to water by high shear mixing, the liquid is then applied to an agricultural product (e.g., fruit or kernel fruit) through a dip tank, a spray lance or a brush bed, or a combination thereof.

Description

TECHNICAL FIELD

[0001] The present invention relates to a composition effective in protecting an agricultural product from superficial scald and / or scuffing, e.g. where the agricultural product is a fruit, e.g. a pome fruit (e.g. a pear). The composition is or comprises a thixotropic aqueous mixture comprising at least one smectite clay and at least one water-soluble polymer. The invention also relates to a method of preparing the composition, a method of coating an agricultural product (e.g. a fruit or a pome fruit (e.g. a pear)) comprising applying the coating composition to the agricultural product, and methods and uses of the composition for protecting an agricultural product (e.g. a fruit) from superficial scald and / or scuffing damage. BACKGROUND

[0002] Pome fruits (e.g. pears and apples) are often stored for long periods in a controlled atmosphere at temperatures close to freezing. During this long storage period, the fruit's skin develops a brown to black discoloration. This discoloration is known as superficial scald. Currently, the physiology of superficial scald appears to be related to the accumulation of alpha-farnesene oxidized to trienol. This oxidation appears to be triggered by environmental oxygen. It appears that most superficial scald occurs on the fruit's light side. This can be due to the plant's response to sunlight and the accumulation of antioxidants to protect against the harmful effects of the sun.

[0003] It has recently been demonstrated that coating the fruit with squalene reduces superficial scald. Squalene is a naturally occurring polyunsaturated hydrocarbon with antioxidant properties. However, it is an oil and therefore gives the fruit an unpleasant oily feel.

[0004] There is currently no coating available that prevents superficial scald in agricultural products (e.g. fruits) without negatively modifying the agricultural product. Therefore, there is a need for a composition that protects agricultural products (e.g. fruits) from (and can even prevent) superficial scald without negatively modifying the agricultural product. There is also a need for a composition that is not only edible but also organic in order to coat organic agricultural products (e.g. organic fruits) to maintain the organic status of the agricultural product.

[0005] Another major type of damage to agricultural products (particularly fruits) is scuffing. Scuffing is the wear and tear on the surface of an agricultural product due to friction with the surface or bruising due to impact. Scuffing on pome fruits (e.g. pears) appears as brown spots or streaks. These scuffs reduce the attractiveness of the fruit to the consumer and reduce its value. Scuffing damage increases as the fruit ripens.

[0006] Pears are unique among drupes because their skin is very delicate. Pear skin is very susceptible to damage during normal harvesting, sorting, and packing. In many cases, pears are stored in field bins for months before being packed according to retail demand. The longer pears are stored, the more susceptible they are to bruising. It is also common to use ethylene treatment to accelerate ripening of pears. This process makes pears more susceptible to bruising. Compositions known in the art to aid in the handling of pears are inorganic and affect the edibility of the pears after application. Thus, there is a need for a composition to prevent bruising of pears and other agricultural products that is edible and organic for organic agricultural products. SUMMARY

[0007] The present invention relates generally to a composition consisting of or comprising a thixotropic mixture. Thus, the composition of the present invention is a thixotropic composition. The terms "thixotropic mixture" and "thixotropic composition" (or more specifically, "thixotropic aqueous mixture" and "thixotropic aqueous composition") are used interchangeably herein to refer to the compositions and mixtures of the present invention that have thixotropic properties.

[0008] According to a first aspect of the present invention, there is provided a novel thixotropic mixture, which is a thixotropic aqueous mixture comprising at least one smectite clay and a water-soluble polymer.

[0009] In some embodiments, the smectite clay is hydrophobically modified (e.g., hydrophobic). In some embodiments, the water-soluble polymer is a natural water-soluble polymer. In one embodiment, the thixotropic aqueous mixture comprises at least one smectite clay (which can be a hydrophobically modified (e.g., hydrophobic) smectite clay) and a water-soluble polymer (e.g., a natural water-soluble polymer), and further comprises an antioxidant (which can be a natural antioxidant and / or a food-grade antioxidant, e.g., a natural antioxidant oil) and / or a solvent (which is typically a food-grade solvent). For example, in one embodiment, the thixotropic aqueous mixture comprises at least one smectite clay (which can be a hydrophobically modified smectite clay) and a natural water-soluble polymer, and further comprises an antioxidant selected from natural and food-grade antioxidants and / or a food-grade solvent.

[0010] As described herein, when applied to the surface of an agricultural product, the thixotropic aqueous mixture of the present invention forms a thin coating on the surface that serves to protect the agricultural product from tiger stripe damage and / or bruising damage (e.g., prevents tiger stripe damage and / or bruising damage). Thus, the thixotropic aqueous mixture of the present invention is suitable and effective for protecting an agricultural product from bruising damage and / or tiger stripe damage. The thixotropic aqueous mixture is particularly suitable for protecting fruits, such as drupes (e.g., apples or pears).

[0011] The present application also provides methods of making the thixotropic aqueous mixture of the present application, as well as the thixotropic aqueous mixture made by the methods of the present application. The methods generally comprise mixing smectite clay and water-soluble polymer with water under high shear. In some aspects of the present application, all components of the composition are mixed together under high shear.

[0012] Thus, according to a second aspect of the present application, there is provided a method of making a thixotropic aqueous mixture comprising at least one smectite clay (which can be a hydrophobically modified (e.g., hydrophobic) smectite clay) and a water-soluble polymer (e.g., a natural water-soluble polymer). The method comprises mixing the at least one smectite clay and the water-soluble polymer with a solvent under high shear mixing conditions. The solvent generally comprises water, and can consist of water. In some embodiments, the solvent comprises water and a volatile solvent, such as ethanol (e.g., a mixture of water and ethanol). In some embodiments, during the high shear mixing, the at least one smectite clay and the water-soluble polymer are added separately (either simultaneously or sequentially) to water, or to water and ethanol. In other embodiments, the at least one smectite clay and the water-soluble polymer are pre-mixed in powder form, and then mixed with water, or with water and ethanol.

[0013] In some embodiments, after the thixotropic aqueous mixture is made, the method further comprises applying the mixture to an agricultural product, such as a fruit (e.g., a pome fruit, such as an apple or a pear).

[0014] According to a third aspect of the present application, there is provided a method of applying a thixotropic aqueous mixture to an agricultural product, such as a fruit or a pome fruit (e.g., a pear and an apple), the thixotropic aqueous mixture comprising at least one smectite clay (which can be a hydrophobically modified (e.g., hydrophobic) smectite clay) and a water-soluble polymer (e.g., a natural water-soluble polymer). In some embodiments, the thixotropic aqueous mixture comprising at least one smectite clay and a water-soluble polymer is applied to the agricultural product by a dip tank, a spray bar, or a brush bed, or a combination thereof. For example, the thixotropic aqueous mixture can be applied to the agricultural product by a combination of a dip tank and a brush bed. Alternatively, the thixotropic aqueous mixture can be applied to the agricultural product by a combination of a spray bar and a brush bed. In some embodiments, the at least one smectite clay (e.g., a hydrophobic / hydrophobically modified smectite clay) and the water-soluble polymer are mixed with a solvent (e.g., water) under high shear to form a thixotropic aqueous mixture, as described herein, and then applied to the agricultural product, such as a fruit or a pome fruit (e.g., a pear and an apple). The use of these methods to apply the thixotropic aqueous mixture of the present application to the agricultural product reduces the tiger stripe disease of the agricultural product and / or reduces the susceptibility of the agricultural product to bruising.

[0015] According to a fourth aspect of the application, there is provided a method of preparing a thixotropic aqueous mixture comprising at least one smectite clay (which can be a hydrophobic smectite clay (e.g. a hydrophobically modified smectite clay)) and a water-soluble polymer (which can be a natural water-soluble polymer), the method comprising mixing the at least one smectite clay and the water-soluble polymer with a solvent under high shear to form a thixotropic aqueous mixture; and then applying the mixture to an agricultural product, such as a fruit or pome fruit (e.g. an apple or a pear). In some embodiments, the method comprises mixing the at least one hydrophobically modified (e.g. hydrophobic) smectite clay, the water-soluble polymer and an antioxidant (which can be a natural antioxidant and / or a food-grade antioxidant, such as a natural antioxidant oil) with a solvent under high shear to form a thixotropic aqueous mixture, and then applying the mixture to an agricultural product. In some embodiments, the solvent consists of water, or the solvent can comprise water and a volatile solvent such as ethanol (e.g. a mixture of water and ethanol). In some embodiments, the method comprises applying the thixotropic aqueous mixture to the agricultural product by a dip tank, a spray bar or a brush bed, or a combination thereof. In some embodiments, the method comprises applying the thixotropic aqueous mixture to the agricultural product by a spray bar and a brush bed. In some embodiments, the method comprises applying the thixotropic aqueous mixture to the agricultural product by a dip tank and a brush bed. In some embodiments, the method further comprises subsequently drying the solvent to evaporate the solvent.

[0016] In one embodiment, the method comprises mixing a hydrophobically modified (e.g. hydrophobic) smectite clay, a water-soluble polymer (e.g. a natural water-soluble polymer) and an antioxidant (e.g. a natural antioxidant and / or a food-grade antioxidant, such as a natural antioxidant oil) with water under high shear to form a thixotropic fluid, which can be applied to an agricultural product such as a fruit (e.g. a pear) by a spray bar and a brush bed, and subsequently drying the solvent. In one embodiment, the method comprises mixing a hydrophobically modified (e.g. hydrophobic) smectite clay, a water-soluble polymer (e.g. a natural water-soluble polymer) and an antioxidant (e.g. a natural antioxidant and / or a food-grade antioxidant, such as a natural antioxidant oil) with water and ethanol (e.g. a mixture of water and ethanol) under high shear to form a thixotropic fluid, which can be applied to an agricultural product such as a fruit (e.g. a pear) by a spray bar and a brush bed, and subsequently drying the solvent.

[0017] According to a fifth aspect, the present application provides a method of protecting an agricultural product from abrasion damage, comprising applying a thixotropic aqueous mixture of the present application to a surface of the agricultural product. In some embodiments, the method comprises applying the thixotropic aqueous mixture to the agricultural product by a dip tank, a spray bar, or a brush bed, or a combination thereof; for example using a spray bar and a brush bed, or using a dip tank and a brush bed. In some embodiments, the method comprises preparing the thixotropic aqueous mixture using a high shear method as described herein, prior to applying the thixotropic aqueous mixture to the agricultural product.

[0018] According to a sixth aspect, the present application provides a method of protecting an agricultural product from superficial scald damage, comprising applying a thixotropic aqueous mixture of the present application to a surface of the agricultural product. In some embodiments, the method comprises applying the thixotropic aqueous mixture to the agricultural product by a dip tank, a spray bar, or a brush bed, or a combination thereof; for example using a spray bar and a brush bed, or using a dip tank and a brush bed. In some embodiments, the method comprises preparing the thixotropic aqueous mixture using a high shear method as described herein, prior to applying the thixotropic aqueous mixture to the agricultural product.

[0019] According to a seventh aspect, the present application provides use of a thixotropic aqueous composition of the present application for coating an agricultural product, for protecting an agricultural product from abrasion damage, and / or for protecting an agricultural product from superficial scald damage. The present application provides use of a thixotropic aqueous mixture of the present application for protecting an agricultural product (e.g. a fruit or a stone fruit (e.g. a pear)) from abrasion damage and / or from superficial scald damage, the thixotropic aqueous mixture comprising at least one smectite clay (which can be a hydrophobically modified (e.g. hydrophobic) smectite clay) and a water-soluble polymer (e.g. a natural water-soluble polymer). BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The percentage of superficial scald observed in "Nabaco coated" Limonerapears coated with a thixotropic aqueous mixture comprising 5% sodium montmorillonite, 1.5% gum arabic and 0.2% sodium citrate in water, compared to "control" Limonerapears coated with carnauba wax, six days after application.

[0021] Figures 2A-2B The extent of ripening and abrasion damage observed in "Nabaco coated" pears coated with a thixotropic aqueous mixture comprising 4.5% bentonite, 1.32% gum arabic and 0.18% sodium citrate, compared to "control" pears coated with carnauba wax, 9 days after application.

[0022] Figure 3The degree of russeting observed in "Nabaco coated" Bartlett pears coated with a thixotropic aqueous mixture comprising 4.6% bentonite, 1.4% gum arabic, and 0.15% sodium citrate is shown compared to "control" Bartlett pears coated with carnauba wax, 5 days after application.

[0023] Figures 4A-4B The degree of russeting observed in "Nabaco coated" Bartlett pears coated with a thixotropic aqueous mixture comprising 4.6% bentonite, 1.4% gum arabic, and 0.15% sodium citrate is shown compared to "control" Bartlett pears coated with carnauba wax, 5 days after application.

[0024] Figures 5A-5B The degree of russeting observed in "Nabaco coated" Bartlett pears coated with a thixotropic aqueous mixture comprising 4.6% bentonite, 1.4% gum arabic, and 0.15% sodium citrate is shown compared to "control" Bartlett pears coated with carnauba wax, 5 days after application.

[0025] Figure 6 The percentage of rub-off measured at 1 day, 3 days, 5 days, and 7 days after application in "Nabaco coated" Bartlett pears coated with a thixotropic aqueous mixture comprising 4.5% bentonite, 1.32% gum arabic, and 0.18% sodium citrate is plotted compared to "control" Bartlett pears coated with carnauba wax.

[0026] Figure 7 The percentage of rub-off measured at 1 day, 3 days, 5 days, and 7 days after application in "Nabaco coated" Bartlett pears coated with a thixotropic aqueous mixture comprising 4.5% bentonite, 1.32% gum arabic, and 0.18% sodium citrate is plotted compared to "control" Bartlett pears coated with carnauba wax. DETAILED DESCRIPTION

[0027] The following detailed description is provided to enable one of ordinary skill in the art to make and use the application. For purposes of explanation, specific details are set forth to provide a thorough understanding of the application. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the present application. Descriptions of specific applications are provided only as representative examples. Various modifications to the embodiments described herein will be readily apparent to those of ordinary skill in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the scope of the application. The present application is not intended to be limited to the embodiments shown, but is to be accorded the widest possible scope consistent with the principles and features disclosed herein.

[0028] It has been unexpectedly discovered that certain water-soluble polymers and smectite clays form a high thixotropic fluid when mixed under high shear in water, and that when applied to an agricultural product such as a fruit (e.g., an apple or a pear), these mixtures form a coating that protects the agricultural product to a large extent from superficial russeting damage and / or bruising damage. Furthermore, the combination of smectite clay, water-soluble polymer, antioxidant (e.g., natural antioxidant and / or food grade antioxidant such as natural antioxidant oil), and solvent (typically a food grade solvent) forms a thixotropic fluid when mixed under high shear, which can subsequently be used to coat an agricultural product such as a pome fruit (e.g., an apple or a pear) to protect against and optionally prevent superficial russeting and / or bruising damage. The present invention provides a solution to the problem of superficial russeting and / or bruising damage to agricultural products.

[0029] The thixotropy of the fluid is critical to the prevention of superficial russeting and bruising phenomena. The high shear applied during the mixing and / or application stage reduces the viscosity of the thixotropic aqueous mixture and reduces the flow resistance. For example, when applying the coating mixture to an agricultural product using a spray bar, the shear applied by the pump and nozzle reduces the viscosity of the thixotropic aqueous mixture and reduces the flow resistance during spraying (i.e., the thixotropic mixture is thinner as it is dispensed through the nozzle). Once the spray impacts the surface of the agricultural product, the viscosity of the thixotropic aqueous mixture returns and the thixotropic aqueous mixture forms a fairly thick coating or film on the surface of the agricultural product. The use of a brush bed is advantageous as it can further level the coating on the agricultural product, making the coating more uniform. Furthermore, it reorients the platelets of the smectite clay so that they are parallel (i.e., aligned) with the surface of the agricultural product. Thus, the brush bed enhances the coating.

[0030] When the coated agricultural product (e.g., fruit) encounters an abrasive surface, the thixotropic coating reduces in viscosity under shear, which imparts lubricity to the surface, thereby reducing bruising. As processing and packaging proceeds, the coating dries to a uniform coating, which is preferably transparent, making the skin more robust and less prone to bruising. It is difficult to judge with the naked eye which fruits have the coating. The individual components do not produce the same anti-bruising effect.

[0031] In a first aspect, the present invention provides a thixotropic mixture comprising at least one smectite clay and a water-soluble polymer. The thixotropic mixture is a thixotropic aqueous mixture. The thixotropic aqueous mixture is used to protect an agricultural product from (e.g., prevent) superficial russeting and / or bruising damage.

[0032] As used herein, the term "thixotropic" refers to a mixture having non-Newtonian fluid dynamics, whose flow properties (e.g., apparent viscosity) vary with shear rate and shear duration.

[0033] In some embodiments, the at least one smectite clay is montmorillonite, bentonite, hectorite, or laponite (sodium lithium magnesium silicate, Na 0.7 Si8Mg 5.5 Li 0.3 O 20 (OH)4), or a mixture of any two, any three, or all four thereof. In some embodiments, the at least one smectite clay is selected from sodium montmorillonite, sodium bentonite, sodium hectorite, or laponite, or a mixture of any two, any three, or all four thereof. For example, the smectite clay can be sodium montmorillonite or sodium bentonite.

[0034] In some embodiments, the thixotropic aqueous mixture comprises the at least one smectite clay in an amount of 1.0 wt.% to 7.0% wt.% (percent of total weight of the thixotropic aqueous mixture). In some embodiments, the thixotropic aqueous mixture comprises sodium montmorillonite in an amount of 1.0 wt.% to 7.0% wt.% (percent of total weight of the thixotropic aqueous mixture). In some embodiments, the thixotropic aqueous mixture comprises bentonite in an amount of 1.0 wt.% to 7.0% wt.% (percent of total weight of the thixotropic aqueous mixture). In some embodiments, the thixotropic aqueous mixture comprises a hydrophobically modified smectite clay in an amount of 1.0 wt.% to 7.0% wt.% (percent of total weight of the thixotropic aqueous mixture).

[0035] In some embodiments, the at least one smectite clay is present in the thixotropic aqueous mixture in an amount of 1.0 wt.% to 6.0 wt.%, for example, 1.5 wt.% to 5.5 wt.%, 1.0 wt.% to 5.0 wt.%, 2.0 wt.% to 5.5 wt.%, or 2.0 wt.% to 5.0 wt.% (percent of total weight of the thixotropic aqueous mixture).

[0036] In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of 0.5 wt.% to 4.5 wt.% (percent of total thixotropic aqueous mixture weight), for example, 0.5 wt.% to 3.5 wt.%, 0.5 wt.% to 2.5 wt.%, 1.0 wt.% to 2.5 wt.%; or 1.0 wt.% to 4.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.5 wt.%, 1.5 wt.% to 3.0 wt.%; or 2.0 wt.% to 3.5 wt.% or 2.0 wt.% to 3.0 wt.% (percent of total thixotropic aqueous mixture weight). In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of 2.0 wt.% to 3.0 wt.% (percent of total thixotropic aqueous mixture weight) by weight of the total thixotropic aqueous mixture. In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of or about 2.4 wt.% (percent of total thixotropic aqueous mixture weight). For example, the thixotropic aqueous mixture can comprise montmorillonite (e.g., sodium montmorillonite) in an amount of 2.0 wt.% to 3.0 wt.%, for example, about 2.4 wt.% (percent of total thixotropic aqueous mixture weight).

[0037] In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of 3.5 wt.% to 6.5 wt.% (percent of total thixotropic aqueous mixture weight), for example, 4.0 wt.% to 6.0 wt.%, 4.0 wt.% to 5.5 wt.%; or 4.5 wt.% to 6.0 wt.%, or 4.5 wt.% to 5.5 wt.% (percent of total thixotropic aqueous mixture weight). In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of 4.5 wt.% to 5.5 wt.% (percent of total thixotropic aqueous mixture weight). In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of or about 4.5 wt.% or in an amount of or about 5 wt.% (percent of total thixotropic aqueous mixture weight). For example, the thixotropic aqueous mixture can comprise bentonite (e.g., sodium bentonite) in an amount of 4.5 wt.% to 5.5 wt.%, for example, in an amount of or about 4.5 wt.% or in an amount of or about 5 wt.% (percent of total thixotropic aqueous mixture weight).

[0038] In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of 0.5 wt.% to 4.5 wt.% by volume of the total thixotropic aqueous mixture composition. In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay in an amount of 0.5 wt.% to 2.5 wt.% by volume of the total thixotropic aqueous mixture composition.

[0039] The surface portion of (unmodified) smectite clays is either or even substantially hydrophilic. Due to its hydrophilicity, unmodified smectite clays do not disperse well in hydrophobic polymers, and thus, it is challenging to make compositions comprising smectite clays and hydrophobic polymers. As used herein, "hydrophobically modified smectite clay" refers to a smectite clay that has been hydrophobically modified ("hydrophobic"). The surface of a hydrophobically modified smectite clay is substantially hydrophobic, and can be entirely hydrophobic. Thus, in some embodiments, "hydrophobically modified smectite clay" can be referred to as "hydrophobic smectite clay." Hydrophobically modified smectite clays (e.g., hydrophobic smectite clays) have the advantageous characteristic of being oleophilic or waxy-philic rather than hydrophilic. A known method of determining whether a smectite clay is hydrophobic or hydrophilic is to use contact angle measurements. Using standard contact angle measurement equipment known in the art, the contact angle of a water droplet on a smectite clay can be measured. The formation of a water droplet on a hydrophobic surface indicates that the associated cohesive forces within the droplet are greater than the forces associated with the interaction of water with the smectite clay surface. A contact angle between the smectite clay surface and the water droplet of greater than 90° indicates that the clay is hydrophobic.

[0040] In some embodiments, at least one smectite clay is hydrophobically modified (e.g., made hydrophobic) by treatment with a compatibilizing agent, or has been previously hydrophobically modified (e.g., made hydrophobic) by treatment with a compatibilizing agent. Generally, a "compatibilizing agent" is an organic modifier that reacts with and hydrophobically modifies a substance. In particular, as used herein, the term "compatibilizing agent" refers to an agent that hydrophobically modifies ("hydrophobic") a smectite clay in a composition, thereby rendering the smectite clay "hydrophobically modified." The compatibilizing agent reacts with the smectite clay to hydrophobically modify the smectite clay particles, thereby rendering the clay compatible with hydrophobic polymers. Specifically, the compatibilizing agent reacts with the smectite clay by bonding with exchangeable sodium ions on the surface of the clay through ionic dipole bonding via OH groups, thereby transforming the surface of the smectite clay from hydrophilic to hydrophobic.

[0041] Ionic liquids are commonly used compatibilizing agents. Ionic liquids can be composed of combinations of organic cations (including: ammonium, (phosphonium), sulfonium (sulfonium), imidazolium, pyrrolidinium, piperidinium, and / or pyridinium) with several organic and inorganic anions. Compatibilizing agents that can be used to make the hydrophobically modified smectite clays of the present invention include sodium citrate, mono- or di-glycerides of natural fats, and / or mono- or di-esters of pentaerythritol. In some embodiments, the thixotropic compositions of the present invention comprise sodium citrate, which serves both as an antioxidant (as described herein) and as a compatibilizing agent for hydrophobically modifying smectite clays.

[0042] The thixotropic aqueous mixture of the present application comprises a water-soluble polymer. In some embodiments, the water-soluble polymer is a natural water-soluble polymer. As used in the present context, the term "natural" or "naturally occurring" refers to a water-soluble polymer that occurs in nature or is derived from nature and is not manufactured or produced by humans. The term does not require that the polymer be "obtained directly from nature." The "natural" or "naturally occurring" water-soluble polymer can be a nature-identical, but this is not required. Since the mixture will be applied to an agricultural product, the water-soluble polymer is typically a food-grade water-soluble polymer. As used herein, the term "food-grade" refers to a substance that is safe for human or animal consumption and is allowed to come into direct contact with food intended for human or animal consumption. The water-soluble polymer is typically edible, meaning that it is safe for human or animal consumption.

[0043] In some embodiments, the water-soluble polymer is or comprises gum arabic or pectin or a combination thereof. In some embodiments, the water-soluble polymer is gum arabic. In some embodiments, the thixotropic aqueous mixture does not comprise the polymer PVOH; for example, in some embodiments, the thixotropic aqueous mixture does not comprise any synthetic or semi-synthetic polymer.

[0044] In some embodiments, the thixotropic aqueous mixture comprises a water-soluble polymer (e.g., a natural water-soluble polymer) in an amount of 0.5 wt.% to 5.0 wt.% (percent of the total weight of the thixotropic aqueous mixture). In some embodiments, the thixotropic aqueous mixture comprises gum arabic in an amount of 0.5 wt.% to 5.0 wt.% (percent of the total weight of the thixotropic aqueous mixture). In some embodiments, the thixotropic aqueous mixture comprises pectin in an amount of 0.5 wt.% to 5.0 wt.% (percent of the total weight of the thixotropic aqueous mixture).

[0045] In some embodiments, the thixotropic aqueous mixture comprises a water-soluble polymer in an amount of 0.5 wt.% to 4.5 wt.% (percent of total thixotropic aqueous mixture composition by weight); for example, 0.5 wt.% to 4.0 wt.%, 0.5 wt.% to 3.5 wt.%, 0.5 wt.% to 3.0 wt.%, or 0.5 wt.% to 2.5 wt.%; or 1.0 wt.% to 3.5 wt.%, 1.0 wt.% to 3.0 wt.%, or 1.0 wt.% to 2.5 wt.% (percent of total thixotropic aqueous mixture composition by weight). In some embodiments, the thixotropic aqueous mixture comprises a water-soluble polymer in an amount of 1.0 wt.% to 2.0 wt.% or 1.5 wt.% to 2.5 wt.% (percent of total thixotropic aqueous mixture composition by weight). For example, the thixotropic aqueous mixture can comprise gum arabic in an amount of 1.0 wt.% to 2.0 wt.%, for example, 1.2 wt.% to 1.5 wt.% (percent of total thixotropic aqueous mixture composition by weight). For example, the thixotropic aqueous mixture can comprise pectin in an amount of 1.5 wt.% to 2.5 wt.%, for example, in an amount of or about 1.9 wt.% (percent of total thixotropic aqueous mixture composition by weight).

[0046] In some embodiments, the thixotropic aqueous mixture comprises a water-soluble polymer in an amount of 0.5 wt.% to 4.5 wt.% (percent of total thixotropic aqueous mixture composition by weight); for example, 0.5 wt.% to 4.0 wt.%, 0.5 wt.% to 3.5 wt.%, 0.5 wt.% to 3.0 wt.%, or 0.5 wt.% to 2.5 wt.%; or 1.0 wt.% to 3.5 wt.%, 1.0 wt.% to 3.0 wt.%, or 1.0 wt.% to 2.5 wt.% (percent of total thixotropic aqueous mixture composition by weight). In some embodiments, the thixotropic aqueous mixture comprises a water-soluble polymer in an amount of 1.0 wt.% to 2.0 wt.% or 1.5 wt.% to 2.5 wt.% (percent of total thixotropic aqueous mixture composition by weight). For example, the thixotropic aqueous mixture can comprise gum arabic in an amount of 1.0 wt.% to 2.0 wt.%, for example, 1.2 wt.% to 1.5 wt.% (percent of total thixotropic aqueous mixture composition by weight). For example, the thixotropic aqueous mixture can comprise pectin in an amount of 1.5 wt.% to 2.5 wt.%, for example, in an amount of or about 1.9 wt.% (percent of total thixotropic aqueous mixture composition by weight).

[0047] In some embodiments, the thixotropic aqueous mixture comprises montmorillonite (e.g., sodium montmorillonite) and gum arabic. In some embodiments, the thixotropic aqueous mixture comprises 1.0 wt.% to 7.0 wt.% sodium montmorillonite and 0.5 wt.% to 2.0 wt.% gum arabic (percent of total thixotropic aqueous mixture composition by weight); for example, 2.0 wt.% to 3.0 wt.% sodium montmorillonite and 0.5 wt.% to 1.5 wt.% gum arabic, or 4.0 wt.% to 6.0 wt.% sodium montmorillonite and 1.0 wt.% to 2.0 wt.% gum arabic. For example, the thixotropic aqueous mixture can comprise 2.4 wt.% sodium montmorillonite and 1.2 wt.% gum arabic. In another example, the thixotropic aqueous mixture can comprise 5.0 wt.% sodium montmorillonite and 1.5 wt.% gum arabic.

[0048] In some embodiments, the thixotropic aqueous mixture comprises bentonite (e.g., sodium bentonite) and gum arabic. In some embodiments, the thixotropic aqueous mixture comprises 1.0 wt.% to 7.0 wt.% bentonite and 0.5 wt.% to 2.0 wt.% gum arabic (percent of total weight of the thixotropic aqueous mixture); for example, 4.0 wt.% to 5.0 wt.% bentonite and 1.0 wt.% to 2.0 wt.% gum arabic. For example, the thixotropic aqueous mixture can comprise about 4.5 wt.% bentonite and 1.0 wt.% to 1.5 wt.% gum arabic.

[0049] In other embodiments, the thixotropic aqueous mixture comprises bentonite (e.g., sodium bentonite) and pectin. In some embodiments, the thixotropic aqueous mixture comprises 1.0 wt.% to 7.0 wt.% bentonite and 1.0 wt.% to 3.0 wt.% pectin (percent of total weight of the thixotropic aqueous mixture); for example, 4.0 wt.% to 5.0 wt.% bentonite and 1.0 wt.% to 2.5 wt.% pectin. For example, the thixotropic aqueous mixture can comprise about 4.3 wt.% bentonite and 1.5 wt.% to 2.0 wt.% pectin.

[0050] Various ratios of at least one smectite clay to water-soluble polymer are contemplated herein. In some embodiments, the weight ratio of the at least one smectite clay to the water-soluble polymer in the thixotropic aqueous mixture is 1 :4 to 4: 1. In one embodiment, the ratio of the at least one smectite clay to the water-soluble polymer in the thixotropic aqueous mixture is 3.5: 1 to 1 : 1, for example, about 3: 1, 2: 1, or 1 : 1.

[0051] In some embodiments, the thixotropic aqueous mixture further comprises an antioxidant. In some embodiments, the antioxidant is a natural antioxidant or a naturally occurring antioxidant. In this context, the term "natural" or "naturally occurring" refers to an antioxidant that occurs in nature or is derived from nature and is not manufactured or produced by humans. The term does not require that the antioxidant be "obtained directly from nature." The "natural" or "naturally occurring" antioxidant can be a nature-identical, but this is not required. Because the mixture will be applied to produce, the antioxidant is typically a food-grade antioxidant. As used herein, the term "food-grade" refers to a substance that is safe for human or animal consumption and is permitted to come into direct contact with food intended for human or animal consumption. The antioxidant is typically consumable, meaning that it is safe for human or animal consumption.

[0052] In some embodiments, the antioxidant is sodium citrate.

[0053] In some embodiments, the antioxidant is an antioxidant oil, which can be a naturally occurring antioxidant oil. In some embodiments, the antioxidant oil is squalene.

[0054] In some embodiments, the thixotropic aqueous mixture comprises an antioxidant (e.g., a natural and / or food grade antioxidant) in an amount of 0.001 wt.% to 1.00 wt.% (percent of total thixotropic aqueous mixture weight). In some embodiments, the antioxidant is present in an amount of 0.01 wt.% to 1.00 wt.%, 0.05 wt.% to 0.75 wt.%, or 0.05 wt.% to 0.5 wt.%; or 0.1 wt.% to 0.5 wt.%, 0.1 wt.% to 0.4 wt.%, 0.1 wt.% to 0.3 wt.%, or 0.15 wt.% to 0.25 wt.% (percent of total thixotropic aqueous mixture weight). In some embodiments, the thixotropic aqueous mixture comprises an antioxidant in an amount of 0.1 wt.% to 0.2 wt.% (percent of total thixotropic aqueous mixture weight). In some embodiments, the thixotropic aqueous mixture comprises sodium citrate in an amount of 0.05 wt.% to 0.25 wt.% (percent of total thixotropic aqueous mixture weight); for example, in an amount of 0.1 wt.% to 0.2 wt.%, or in an amount of or about 0.2 wt.%.

[0055] In some embodiments, the thixotropic aqueous mixture comprises squalene in an amount of 0.75% to 0.90% of the total thixotropic aqueous mixture weight.

[0056] In some embodiments, the thixotropic aqueous mixture comprises a food grade antioxidant in an amount of 0.001 wt.% to 0.05 wt.% by volume of the total composition.

[0057] In one embodiment, the thixotropic aqueous mixture comprises montmorillonite (e.g., sodium montmorillonite), gum arabic, and sodium citrate. In some embodiments, the thixotropic aqueous mixture comprises 1.0 wt.% to 7.0 wt.% montmorillonite, 0.5 wt.% to 2.0 wt.% gum arabic, and 0.1 wt.% to 0.5 wt.% sodium citrate (percent of total thixotropic aqueous mixture weight); for example, 4.0 wt.% to 6.0 wt.% montmorillonite, 1.0 wt.% to 2.0 wt.% gum arabic, and 0.1 wt.% to 0.3 wt.% sodium citrate. In another example, the thixotropic aqueous mixture can comprise 5.0 wt.% sodium montmorillonite, 1.5 wt.% gum arabic, and 0.2 wt.% sodium citrate.

[0058] In one embodiment, the thixotropic aqueous mixture comprises bentonite (e.g., sodium bentonite), gum arabic, and sodium citrate. In some embodiments, the thixotropic aqueous mixture comprises 1.0 wt.% to 7.0 wt.% bentonite, 0.5 wt.% to 2.0 wt.% gum arabic, and 0.05 wt.% to 0.25 wt.% sodium citrate (percent of total weight of the thixotropic aqueous mixture); for example, 4.0 wt.% to 5.0 wt.% bentonite, 1.0 wt.% to 2.0 wt.% gum arabic, and 0.1 wt.% to 0.2 wt.% sodium citrate. For example, the thixotropic aqueous mixture can comprise about 4.5 wt.% bentonite, 1.3 wt.% to 1.4 wt.% gum arabic, and 0.1 wt.% to 0.2 wt.% sodium citrate (percent of total weight of the thixotropic aqueous mixture).

[0059] In one embodiment, the thixotropic aqueous mixture comprises bentonite (e.g., sodium bentonite), pectin, and sodium citrate. In some embodiments, the thixotropic aqueous mixture comprises 1.0 wt.% to 7.0 wt.% bentonite, 1.0 wt.% to 3.0 wt.% pectin, and 0.1 wt.% to 0.25 wt.% sodium citrate (percent of total weight of the thixotropic aqueous mixture); for example, 4.0 wt.% to 5.0 wt.% bentonite, 1.0 wt.% to 2.5 wt.% pectin, and 0.1 wt.% to 0.2 wt.% sodium citrate. For example, the thixotropic aqueous mixture can comprise about 4.3 wt.% bentonite, about 1.9 wt.% pectin, and about 0.18 wt.% sodium citrate (percent of total weight of the thixotropic aqueous mixture).

[0060] The thixotropic aqueous mixture of the present application also comprises one or more solvents. Since the mixture will be applied to an agricultural product, the solvent is typically a food grade solvent. In one embodiment, the solvent is water. Alternatively, the solvent can comprise water and a volatile solvent such as ethanol, for example a mixture of water and ethanol.

[0061] In some embodiments, the solvent is present in an amount of at least 85 wt.% (percent of total weight of the thixotropic aqueous mixture), for example 85 wt.% to 98 wt.%, or 90 wt.% to 97.5 wt.%; optionally 90 wt.% to 98 wt.% (percent of total weight of the thixotropic aqueous mixture). In some embodiments, the solvent is added in an amount of at least 90 wt.%, at least 95 wt.%, or at least 97 wt.% (percent of total weight of the thixotropic aqueous mixture). In some embodiments, the mixture comprises 25% by volume ethanol and 75% by volume water.

[0062] In some embodiments, the thixotropic aqueous mixture comprises ethanol in an amount of 5 wt.% to 28 wt.% (percent of total weight of the thixotropic aqueous mixture), for example, 5 wt.% to 25 wt.% or 5 wt.% to 20 wt.%.

[0063] In some embodiments, the thixotropic aqueous mixture comprises a hydrophobically modified (e.g., hydrophobic) smectite clay, a water-soluble polymer (e.g., a natural water-soluble polymer), an antioxidant (e.g., a natural and / or food-grade antioxidant, such as a natural antioxidant oil), and a solvent (typically a food-grade solvent). In some embodiments, the thixotropic aqueous mixture comprises a hydrophobically modified (e.g., hydrophobic) smectite clay, a natural water-soluble polymer (e.g., gum arabic or pectin), a natural and / or food-grade antioxidant, and a food-grade solvent. In any of the embodiments of the present application that use a hydrophobically modified smectite clay, the solvent can comprise water and a volatile solvent (typically ethanol). For example, the thixotropic aqueous mixture can comprise a hydrophobically modified sodium montmorillonite or bentonite, gum arabic, sodium citrate, and a solvent comprising water and ethanol; or, the thixotropic aqueous mixture can comprise a hydrophobically modified bentonite, gum arabic or pectin, sodium citrate, and a solvent comprising water and ethanol.

[0064] The present application also includes a thixotropic mixture for protecting an agricultural product (e.g., a drupaceous fruit) from tiger stripe damage, the thixotropic mixture comprising at least one hydrophobically modified smectite clay, a naturally occurring antioxidant oil, and a food-grade solvent. Suitable hydrophobically modified (e.g., hydrophobic) smectite clays for use in the mixture include a hydrophobically modified montmorillonite (e.g., sodium montmorillonite), bentonite, sodium hectorite, saponite, or a mixture thereof. For example, the smectite clay can be rendered hydrophobic by treatment with a compatibilizing agent (e.g., sodium citrate, or a mono- or di-glyceride, or a mono-ester of pentaerythritol). In some embodiments, the natural antioxidant oil is squalene, wherein the squalene is optionally present in a minor amount, for example, about 0.75 wt.% to 0.9 wt.% (percent of total weight of the thixotropic mixture). In these and other embodiments of the present application that use a hydrophobically modified smectite clay, the solvent typically comprises ethanol. For example, the ethanol can be present in the thixotropic mixture in an amount of 5 wt.% to 28 wt.% (percent of total weight of the thixotropic mixture).

[0065] In some embodiments of any of the thixotropic mixtures / compositions of the present application, the thixotropic mixture is an aqueous colloidal dispersion comprising 1% to 7% solids; for example, 2% to 7% solids, 3% to 7% solids, 5% to 7% solids, or 6% to 7% solids; or 1% to 5% solids or 3% to 4% solids. In an aqueous colloidal dispersion, the solids (including clay) are not dissolved in solution, but are present in a dispersed state, such that the individual platelets of clay remain in the colloidal dispersion. An aqueous colloidal dispersion is measured by drying a known volume of the dispersion and weighing the solids content of the mixture.

[0066] In some embodiments, the thixotropic mixtures of the present application do not require additional components to achieve the desired results. For example, in some embodiments, the thixotropic mixtures do not contain calcium salts. Thus, in some embodiments, a thixotropic aqueous mixture is provided that consists of at least one smectite clay and a water-soluble polymer. In some embodiments, the thixotropic aqueous mixture consists of at least one smectite clay (e.g., a hydrophobic smectite clay (e.g., a hydrophobically modified smectite clay)), a water-soluble polymer (e.g., a natural water-soluble polymer), an antioxidant (e.g., a natural antioxidant and / or a food-grade antioxidant, such as a natural antioxidant oil), and a solvent (typically a food-grade solvent, such as water or a mixture of water and ethanol).

[0067] In some embodiments, the thixotropic mixture is edible. As used herein, the term "edible" refers to an item that is safe for human or animal consumption.

[0068] In some embodiments, the thixotropic mixture does not have a negative modifying effect on the agricultural product to which it is applied. For example, if the agricultural product is organic, then the thixotropic mixture is also organic. As used herein, the term "organic" refers to components that do not change the organic status of the agricultural product once applied to the agricultural product. Thus, these components meet the standards set for organic production of agricultural products, such as the regulations for the "organic" claim set by the United States Department of Agriculture (USDA) National Organic Program (NOP). In some embodiments, the organic thixotropic aqueous mixture does not contain any inorganic components, where the term "inorganic" as used herein refers to components that change the organic status of the agricultural product once applied to the agricultural product.

[0069] Thus, in some embodiments, the thixotropic aqueous mixture described herein is an edible organic composition for preventing rind rub and / or rub damage to an agricultural product. In some embodiments, the thixotropic aqueous mixture is an organic thixotropic aqueous mixture for protecting organic fruit (e.g., pears) from rub damage, comprising at least one smectite clay and a naturally water-soluble polymer. In some embodiments, the thixotropic aqueous mixture is an organic thixotropic aqueous mixture for protecting stone fruit from rind rub damage, comprising at least one smectite clay and a water-soluble polymer. In some embodiments, the thixotropic aqueous mixture is an organic thixotropic mixture for protecting stone fruit from rind rub damage, comprising at least one hydrophobically modified (e.g., hydrophobic) smectite clay, a naturally occurring antioxidant oil, and a food-grade solvent.

[0070] The thixotropic mixture is prepared by mixing its components together under high shear to form a thixotropic fluid, which can then be applied to an agricultural product, such as a fruit or stone fruit (e.g., an apple or a pear). The thixotropic mixture of the present invention forms a coating on the surface of the agricultural product that protects the agricultural product from (e.g., prevents) damage caused by rub and / or rind rub. Thus, in some embodiments, the thixotropic aqueous mixture described herein is a novel composition for preventing rub damage and / or rind rub of an agricultural product (e.g., a fruit or stone fruit (e.g., an apple and a pear)).

[0071] The present invention also provides methods of making the thixotropic mixture of the present invention, as well as mixtures made by these methods. The methods include high shear mixing.

[0072] Thus, in a second aspect, the present invention provides a method of making the thixotropic aqueous mixture of the present invention. The method includes mixing at least one smectite clay and a water-soluble polymer (e.g., a naturally water-soluble polymer) with a solvent under high shear to form the thixotropic aqueous mixture.

[0073] The descriptions and definitions provided herein in the context of the thixotropic mixture of the present invention also apply to the methods of the present invention for making the thixotropic mixture. In particular, the smectite clay, water-soluble polymer, and optional antioxidant used in the methods can each be any of the smectite clays, water-soluble polymers, and antioxidants described herein (respectively) in the context of the thixotropic mixture of the present invention. Moreover, any of these smectite clays can be hydrophobically modified, as described herein. In some embodiments, the solvent used in the methods comprises or consists of water. In some embodiments, particularly those involving a hydrophobically modified smectite clay, the solvent comprises water and a volatile solvent (typically ethanol).

[0074] The method of the present invention for preparing a thixotropic mixture involves at least one step that is performed under high shear. Any known high shear mixer (e.g., a blade mixer, a Cowles dissolver, or a colloid mill) can be used to perform any of the methods or method steps described herein that involve high shear mixing. High shear mixing requires equipment with high RPM and high horsepower to ensure that the dispersing blades can reach top speeds of 2500 to 5000 feet per minute. The high shear mixing process can take 1 to 2 hours. For mixing of smaller batch quantities of the composition, a high shear blender can be used. High shear methods are advantageous because they enable rapid mixing of the smectite clay and the water-soluble polymer and / or other components in the solvent to form a thixotropic mixture that ensures uniform dispersion of the smectite clay particles (platelets). When standard mixing methods that do not involve high shear (e.g., a tank with a paddle mixer) are used, the mixing of the smectite clay and the water-soluble polymer and / or other components in the solvent never fully disperses the smectite clay to form a uniformly dispersed mixture. This is because the smectite clay platelets are held together in stacks by a number of weak bonds (e.g., hydrogen bonds and ion-dipole interactions) that collectively form a large cohesive energy. Standard mixing is not sufficient to overcome this cohesive energy. When methods involving high shear are used, the increased energy and large forces that result from high shear are sufficient to break the forces that hold these smectite clay platelets together. Thus, the methods of the present invention for preparing the compositions using high shear are efficient.

[0075] In some embodiments, the method comprises adding at least one smectite clay and a water-soluble polymer to water, and then high shear mixing the smectite clay, water-soluble polymer, and water. In some embodiments, at least one smectite clay, a water-soluble polymer, and an antioxidant are added to water and mixed under high shear. In some embodiments, the method comprises adding at least one smectite clay and a water-soluble polymer to a mixture of water and ethanol, and then high shear mixing the smectite clay, water-soluble polymer, water, and ethanol. In some embodiments, at least one smectite clay (e.g., a hydrophobic / hydrophobically modified smectite clay), a water-soluble polymer, and an antioxidant are added to a mixture of water and ethanol and mixed under high shear.

[0076] In some embodiments, at least one smectite clay and a water-soluble polymer are mixed together in powder form, and then the smectite clay and water-soluble polymer "premix" is added to water, or to a mixture of water and ethanol, and mixed under high shear mixing conditions. In some embodiments, at least one smectite clay, a water-soluble polymer, and an antioxidant are mixed together in powder form, and then the smectite clay, water-soluble polymer, and antioxidant "premix" is added to water, or to a mixture of water and ethanol, and mixed under high shear mixing conditions. In some embodiments, the method comprises mixing together sodium montmorillonite or bentonite, gum arabic, and sodium citrate in powder form, and then adding the mixture to water, or to a mixture of water and ethanol, and mixing under high shear mixing conditions. In some embodiments of these methods, the smectite clay is hydrophobically modified (e.g., hydrophobic); and a solvent comprising water and ethanol can optionally be used.

[0077] In some embodiments, at least one smectite clay and a water-soluble polymer are added separately to a solvent (e.g., water or a mixture of water and ethanol), and then mixed under high shear. In some embodiments, an antioxidant (e.g., a natural and / or food-grade antioxidant, such as a natural antioxidant oil) is also added separately to the solvent and mixed under high shear. In some embodiments, sodium montmorillonite or bentonite, gum arabic, and sodium citrate are added separately to a solvent (e.g., water or a mixture of water and ethanol) and mixed under high shear mixing. In some embodiments of these methods, the smectite clay is hydrophobically modified (e.g., hydrophobic); and a solvent comprising water and ethanol can optionally be used. In any of these embodiments, adding the components "separately" to the solvent includes adding all of the components to the solvent at the same time, adding two or more components at the same time and subsequently (either simultaneously or sequentially) adding one or more other components, or adding each component sequentially.

[0078] As discussed herein, the antioxidant sodium citrate can also act as a compatibilizing agent to hydrophobically modify the smectite clay. High shear mixing of the sodium citrate in the presence of the smectite clay in the solvent facilitates mixing and reaction of the sodium citrate with the smectite clay to hydrophobically modify the smectite clay, thereby forming a hydrophobically modified (e.g., hydrophobic) smectite clay (i.e., converting the smectite clay to a "hydrophobic smectite clay"), as described above.

[0079] In some embodiments of any of the methods of the present application for preparing a thixotropic composition, the smectite clay and the water-soluble polymer are added to the solvent in a ratio of 1 :4 to 4: 1, such as in a ratio of 3.5: 1 to 1 : 1, such as about 3: 1, 2: 1, or 1 : 1 (wt / wt).

[0080] The present application also provides a thixotropic mixture prepared by any method of the present application, such as a thixotropic aqueous mixture comprising at least one smectite clay, a water-soluble polymer, and optionally an antioxidant and a solvent (each as described herein). The thixotropic composition prepared by any method of the present application can be edible, and can optionally be organic. These terms have the meanings defined herein.

[0081] In some embodiments of any method of the present application for preparing a thixotropic mixture, the method further comprises applying the thixotropic mixture to the surface of an agricultural product. For example, the mixture can be applied using a spray bar, a dip tank, a brush bed, inkjet printing, gravure printing, or a doctor blade or combinations thereof. For example, the thixotropic mixture prepared according to any method of the present application can be applied to the surface of an agricultural product using a combination of a spray bar and a brush bed or using a dip tank and a brush bed. In some embodiments, the thixotropic mixture is applied to the agricultural product prior to harvest, but in other embodiments, the thixotropic mixture is applied after harvest. The method can further comprise drying the composition after application (e.g., by applying heat), but more typically, allowing the composition to dry naturally under ambient conditions. The thixotropic mixture forms a coating on the surface of the agricultural product to which it is applied. The coating serves to protect the agricultural product from rind damage and / or bruise damage.

[0082] The present application also provides a method of applying a thixotropic mixture of the present application to the surface of an agricultural product to provide one or more technical effects as described herein. The descriptions and definitions provided herein in the context of the thixotropic mixtures of the present application also apply to the following method for protecting an agricultural product from bruise damage and / or rind damage.

[0083] Thus, in a fourth aspect, the present application provides a method of protecting an agricultural product from bruise damage, comprising applying a thixotropic mixture of the present application to the surface of the agricultural product.

[0084] In a fifth aspect, the present application provides a method of protecting an agricultural product from rind damage, comprising applying a thixotropic mixture of the present application to the surface of the agricultural product.

[0085] As used herein, the term "agricultural product" means a crop produced on a farm. In some embodiments, the agricultural product is a fruit. In some embodiments, the agricultural product is a pome fruit, a citrus fruit, or a tomato. The present application is particularly suitable for pome fruits, more particularly apples, pears, and / or quinces. In some embodiments relating to bruising, the agricultural product is a pear. In some embodiments, the agricultural product is a vegetable. For example, the vegetable agricultural product can be a cucumber or a mushroom.

[0086] For example, bruise damage occurs during the harvesting, sorting, and packing of agricultural products, particularly pome fruit such as apples and pears. Protecting agricultural products from bruise damage includes reducing or even preventing bruise damage. Reduction of bruise damage is defined by comparison to the bruise damage of the same agricultural product without any coating mixture (uncoated control) or by comparison to the bruise damage of the same product coated with a conventional composition known in the art. Methods of observing and measuring bruise damage are known in the art, for example, determining the percentage of bruise damage on an agricultural product by image analysis or by the naked eye. In some embodiments, when evaluated from 1 day to 7 days after application, agricultural products (e.g., pears) coated with the thixotropic composition of the present application exhibit a significant reduction in bruise damage compared to the same agricultural product (e.g., pears) coated with a conventional carnauba wax coating. For example, in some embodiments, agricultural products coated with the thixotropic mixture of the present application exhibit at least a 50% reduction in bruise damage compared to the same agricultural product coated with a conventional control composition. In some embodiments, agricultural products coated with the thixotropic mixture of the present application exhibit a reduction in bruise damage and a slowing of ripening compared to conventionally coated agricultural products.

[0087] Tiger map damage occurs, for example, during the cold storage of produce, particularly pome fruit such as apples and pears. Protecting produce from tiger map damage includes reducing or even preventing tiger map damage. Reduction of tiger map damage is defined by comparison to the tiger map damage of the same produce without any coating mixture (uncoated control) or by comparison to the tiger map damage of the same produce coated with a conventional composition known in the art. Methods of observing and measuring tiger map damage are known in the art, for example, by image analysis or by visual determination of the percentage of tiger map damage on produce. For example, in some embodiments, when evaluated 1 to 7 days after application, pome fruit (e.g., pears) coated with the thixotropic aqueous mixture of the present application exhibit significantly reduced tiger map damage compared to the same fruit (e.g., pears) coated with a conventional, carnauba wax-based composition. For example, when evaluated 6 days after application, the percentage of pome fruit with less than 50% tiger map is at least twice as high for fruit coated with the thixotropic aqueous mixture of the present application compared to fruit coated with a conventional control composition. In some embodiments, when evaluated 5 to 7 days after application, pome fruit (e.g., pears) coated with the thixotropic aqueous mixture of the present application are observed to have tiger map on less than 10% of the fruit surface; whereas pome fruit (e.g., pears) coated with a conventional control composition exhibit tiger map on 40% to 80% of the fruit surface when evaluated 5 to 7 days after application. In other embodiments, the thixotropic aqueous composition of the present application prevents tiger map of pome fruit. For example, in some embodiments, when evaluated 9 days after application, pome fruit (e.g., apples) coated with the thixotropic composition of the present application exhibit no tiger map at all; whereas the same fruit (e.g., apples) coated with carnauba wax exhibit tiger map on 30% to 40% of the fruit surface when evaluated 9 days after application.

[0088] In some embodiments, the thixotropic mixture is applied to the produce prior to harvest, but in other embodiments, the thixotropic mixture is applied after harvest. Applying the mixture to the produce prior to harvest has the advantage of providing protection against bruise damage that can occur during the harvesting process. The best results are seen when the thixotropic mixture is applied prior to harvest, but substantial effects on tiger map and bruise damage are also seen if the produce is coated after it has been stored.

[0089] The thixotropic mixture used in the method of protecting an agricultural product from abrasion damage and / or russeting damage can be any thixotropic mixture of the present invention described herein. In some embodiments, the thixotropic mixture used in the method of protecting an agricultural product from abrasion damage and / or russeting damage is a thixotropic aqueous mixture comprising at least one smectite clay (which can be a hydrophobically modified (e.g., hydrophobic) smectite clay) and a water-soluble polymer (e.g., a natural water-soluble polymer). In some embodiments, the thixotropic aqueous mixture comprises at least one smectite clay, a water-soluble polymer (e.g., a natural water-soluble polymer), and an antioxidant (e.g., a natural and / or food-grade antioxidant, such as a natural antioxidant oil). The thixotropic mixture typically further comprises a solvent, which can comprise or consist of water, such as a mixture of water and ethanol as defined herein. In some embodiments, the thixotropic mixture comprises at least one hydrophobically modified smectite clay, an antioxidant, and a solvent (optionally a mixture of water and ethanol). The terms “smectite clay,” “hydrophobically modified smectite clay,” “water-soluble polymer,” “antioxidant,” and “solvent” are defined herein.

[0090] In some embodiments of the method of protecting an agricultural product from abrasion damage and / or russeting damage, the thixotropic mixture is a thixotropic aqueous mixture comprising sodium montmorillonite or bentonite and gum arabic, and it is applied to the agricultural product, such as a fruit or pome fruit (e.g., an apple or a pear), using a combination of a spray bar and a brush bed. In other embodiments, the thixotropic mixture is a thixotropic aqueous mixture comprising sodium montmorillonite or bentonite and gum arabic, and it is applied to the agricultural product, such as a fruit or pome fruit (e.g., an apple or a pear), using a combination of a dip tank and a brush bed. In some embodiments of the method of protecting an agricultural product from abrasion damage and / or russeting damage, the thixotropic mixture is a thixotropic aqueous mixture comprising bentonite and pectin, and it is applied to the agricultural product, such as a fruit or pome fruit (e.g., an apple or a pear), using a combination of a spray bar and a brush bed. In other embodiments, the thixotropic mixture is a thixotropic aqueous mixture comprising bentonite and pectin, and it is applied to the agricultural product, such as a fruit or pome fruit (e.g., an apple or a pear), using a combination of a dip tank and a brush bed. In any of these embodiments, the thixotropic aqueous mixture can further comprise an antioxidant, such as sodium citrate. The thixotropic mixture typically further comprises a solvent, which can comprise or consist of water, such as a mixture of water and ethanol as defined herein. In any of these embodiments, the sodium montmorillonite or bentonite can be hydrophobically modified.

[0091] In some embodiments of any of the methods of the present invention for applying a thixotropic mixture to the surface of an agricultural product or for protecting an agricultural product from abrasion damage and / or russeting damage, the thixotropic mixture is applied to the surface of the agricultural product using a dip tank, a spray bar, or a brush bed, or any combination thereof.

[0092] The dip tank is a device that holds 5,000 to 10,000 liters of the inventive thixotropic mixture and facilitates the submersion of produce (e.g., fruit or pome fruit (e.g., apples and pears)) to coat its surface. When using the dip tank to apply the thixotropic mixture to the produce, the produce is immersed in the thixotropic mixture once for a submersion dwell time of 2 to 5 minutes. After applying the mixture using the dip tank, the produce can be placed on a drain belt to remove excess mixture.

[0093] In some embodiments, the thixotropic mixture is applied to produce, such as fruit or pome fruit (e.g., apples or pears), using a spray bar, optionally in combination with a brush bed. The spray bar is a device that includes a pump and at least one nozzle for spraying the thixotropic aqueous mixture onto the produce. The shear applied by the pump and nozzle of the spray bar during the application phase reduces the viscosity of the thixotropic aqueous mixture and reduces the flow resistance when applying the thixotropic aqueous mixture to the produce (e.g., fruit or pome fruit (e.g., apples or pears)). In some embodiments, the spray bar applies the thixotropic aqueous mixture to the produce at a spray rate ranging from 1,000 pounds to 7,000 pounds of produce per liter of thixotropic mixture (e.g., ranging from 3,000 pounds to 7,000 pounds of produce per liter of thixotropic mixture). Once the spray of the thixotropic aqueous mixture impacts the surface of the produce (i.e., the thixotropic aqueous mixture encounters the surface of the produce), the viscosity returns and a fairly thick coating is formed on the produce. This advantageous feature observed during the application of the inventive thixotropic aqueous mixture is due to the non-Newtonian fluid dynamics of the thixotropic mixture.

[0094] In some embodiments, the coating is applied by spraying using a spray bar after the dip tank and before the brush bed. For example, a spray bar positioned after the produce exits the dip tank and drain belt and / or optionally before the brush bed can be used to spray the thixotropic mixture onto the produce. After the thixotropic aqueous mixture is applied to the surface of the produce, the brush bed brushes each produce. The brush bed typically has 6 to 12 rolling brushes that convey and brush the fruit. The brushes uniformly and efficiently coat the fruit with the thixotropic mixture. The use of a brush bed is particularly advantageous because it ensures a uniform coating of the thixotropic aqueous mixture on the produce and avoids the use of excess mixture. The use of a combination of a spray bar and a brush bed to apply the inventive thixotropic mixture is advantageous because it provides a more comprehensive coating.

[0095] In other embodiments, the thixotropic aqueous mixture is applied to the produce by a combination of a dip tank and a brush bed without spraying.

[0096] The produce can be washed in a soak tank prior to application of the thixotropic mixture. Soak tanks are typically 10,000 liter tanks used to introduce the fruit into the packing line, wash the fruit and remove any debris, such as leaves and twigs. The use of a soak tank is advantageous as it minimizes any damage that can be caused to the produce during these processes. The soak tank and / or dip tank can contain a mild disinfectant, such as peroxyacetic acid.

[0097] These methods of coating produce with the thixotropic aqueous mixture of the present application comprising at least one smectite clay and a water-soluble polymer (and optionally an antioxidant) have been shown to reduce the susceptibility of the produce to bruising and / or superficial scald.

[0098] In a sixth aspect, the present application provides the use of any of the thixotropic mixtures of the present application. The present application provides the use of the thixotropic mixtures of the present application for protecting produce from bruising damage (e.g., for reducing or even preventing bruising damage). The present application also provides the use of the thixotropic mixtures of the present application for protecting produce from superficial scald damage (e.g., for reducing or even preventing superficial scald damage). In these uses of the present application, the reduction in bruising damage and / or superficial scald damage can be determined in comparison to uncoated control produce or in comparison to the same produce coated with a conventional coating composition known in the art. In these uses of the present application, the produce is optionally a fruit or vegetable produce. As discussed herein, the thixotropic mixtures are particularly suitable for protecting pome fruit, such as apples and pears. Accordingly, in some embodiments, the present application provides the use of the thixotropic mixtures of the present application for protecting pome fruit (e.g., apples and / or pears) from bruising damage and / or superficial scald damage. In any of these uses of the present application, the descriptions and definitions provided herein in the context of the thixotropic mixtures of the present application also apply. Accordingly, the thixotropic mixture used can be any of the thixotropic mixtures of the present application described herein.

[0099] Example 1

[0100] A commercial scale trial was conducted on Limonera pears in which "Nabaco coated" Limonera pears were coated with a thixotropic aqueous mixture comprising 5% sodium montmorillonite, 1.5% gum arabic, and 0.2% sodium citrate in water (% values by weight of total composition) compared to "control" Limonera pears coated with Carnauba wax. The thixotropic aqueous mixture was applied to 300 pounds of Limonera pears (Nabaco coated) using a dip tank and brush bed and an application rate of 3000 pounds of pears per liter of thixotropic aqueous mixture was achieved. The control Limonera pears were applied with Carnauba wax at a 20% solids content using a dip tank and brush bed. After the thixotropic aqueous mixture was applied, the Nabaco coated pears and control pears were sorted and packaged. The percent of russeting was measured six days after application. The abrasion damage and / or russeting damage can be measured by image analysis or by the naked eye to determine the percent of abrasion and / or russeting damage. As shown in Table 1 and Figure 1 Figure 1, the percent of control pears with less than 50% russeting was 26% while the percent of Nabaco coated pears with less than 50% russeting was 55%. Thus, the thixotropic aqueous mixture of the present application reduced the russeting of the pears. Table 1 Russeting Results for Limonera Pears Six Days After Application

[0101] Example 2

[0102] A second commercial-scale trial was conducted on Bartlett pears, in which "Nabaco-coated" Bartlett pears were coated with a thixotropic aqueous mixture containing 2.4% sodium montmorillonite and 1.2% gum arabic (% values ​​per unit weight of total composition) in water, compared to a "control" Bartlett pear coated with carnauba wax. The thixotropic aqueous mixture was applied to 5000 lbs of Bartlett pears (Nabaco-coated) using a spray bar and brush bed, achieving an application rate of 3000 lbs of pears per liter of thixotropic aqueous mixture with a solids content of 4% to 6%. Carnauba wax was applied to the control Bartlett pears using a spray bar and brush bed, achieving an application rate of 2500 lbs of pears per liter of carnauba wax with a solids content of 20%. Following application of either the thixotropic aqueous mixture or carnauba wax, the Nabaco-coated pears and the control pears were sorted and packaged. The degree of abrasion, determined three days after application, was 7 out of 25 pears in the control group, compared to 3 out of 25 pears coated with Nabaco (which was coated with the thixotropic aqueous mixture of the present invention). Therefore, this test demonstrates that abrasion damage in pears coated with the thixotropic aqueous mixture of the present invention was reduced by 57%.

[0103] Example 3

[0104] Production line trials were conducted on Bartlett pears, in which "Nabaco-coated" Bartlett pears were coated with a thixotropic aqueous mixture containing 4.5% bentonite, 1.32% gum arabic, and 0.18% sodium citrate (% values ​​based on the weight of the total composition), compared to a control Bartlett pear coated with carnauba wax. The thixotropic aqueous mixture was applied to the Nabaco-coated pears using a spray bar and brush bed, achieving an application rate of 7000 lbs of pears per liter of thixotropic aqueous mixture with a solids content of 4% to 6%. Carnauba wax was applied to the control pears using a spray bar and brush bed, achieving an application rate of 2500 lbs of pears per liter of carnauba wax with a solids content of 20%. After application of either the thixotropic aqueous mixture or carnauba wax, both the Nabaco-coated and control pears were stored at ambient temperature for 9 days, and the degree of scuff damage was then observed. Figure 2A and Figure 2B As shown, compared with the control pear ( Figure 2B Compared to Nabaco-coated pears, Figure 2A The ripening process of pears is slowed down and the degree of bruising damage is significantly reduced. Therefore, this test demonstrates that pears coated with the thixotropic aqueous mixture of the present invention ripen more slowly and suffer less bruising damage.

[0105] Example 4

[0106] A further experiment was conducted on Granny Smith apples that had been cold stored for 10 weeks, in which "Nabaco coated" apples were coated with a thixotropic aqueous mixture comprising 4.3% bentonite, 1.9% pectin, and 0.18% sodium citrate (% values by weight of total composition) as compared to control Granny Smith apples coated with Carnauba wax. The thixotropic aqueous mixture was applied to the Nabaco coated apples using a spray bar and brush bed and an application rate of 7000 pounds of apples per liter of thixotropic aqueous mixture was achieved, with a solids content of 4% to 6%. The Carnauba wax was applied to the control apples using a spray bar and brush bed and an application rate of 2500 pounds of apples per liter of Carnauba wax was achieved, with a solids content of 20%. After the thixotropic aqueous mixture or Carnauba wax was applied, the Nabaco coated apples and control apples were stored at room temperature for 9 days, and then the degree of superficial scald was observed. As shown in Figure 3 Table 1, the degree of superficial scald for the control apples covered 30-40% of the surface of the apples; whereas the Nabaco coated apples had no (0%) superficial scald. Thus, this test demonstrated that the superficial scald of apples coated with the thixotropic aqueous mixture of the present application was completely reduced.

[0107] Example 5

[0108] A further production line test was conducted on pears that had been cold stored for 2 months, in which "Nabaco coated" pears were coated with a thixotropic aqueous mixture comprising 4.5% bentonite, 1.32% gum arabic, and 0.18% sodium citrate (% values by weight of total composition) as compared to control pears coated with Carnauba wax. The thixotropic aqueous mixture was applied to the Nabaco coated pears using a spray bar and brush bed and an application rate of 7000 pounds of pears per liter of thixotropic aqueous mixture was achieved, with a solids content of 4% to 6%. The Carnauba wax was applied to the control pears using a spray bar and brush bed and an application rate of 2500 pounds of pears per liter of Carnauba wax was achieved, with a solids content of 20%. After the thixotropic aqueous mixture was applied, the Nabaco coated pears and control pears were stored at room temperature for 7 days, and then the degree of superficial scald was observed. As shown in Figure 4A and Figure 4B Table 2, the degree of superficial scald for the control pears covered 80% of the surface of the pears ( Figure 4A ); whereas the Nabaco coated pears exhibited less than 10% superficial scald ( Figure 4B ). Thus, this test demonstrated that the superficial scald of pears coated with the thixotropic aqueous mixture of the present application was reduced.

[0109] Example 6

[0110] A commercial production line test was conducted on Bartlett pears that had been cold stored for 30 days, in which "Nabaco coated" Bartlett pears were coated with a thixotropic aqueous mixture comprising 4.6% bentonite, 1.4% gum arabic, and 0.15% sodium citrate (% values by weight of total composition) as compared to control Bartlett pears coated with Carnauba wax. The thixotropic aqueous mixture was applied to the Nabaco coated pears using a spray bar and brush bed and an application rate of 7000 pounds of pears per liter of thixotropic aqueous mixture was achieved with a solids content of 4% to 6%. The Carnauba wax was applied to the control pears using a spray bar and brush bed and an application rate of 2500 pounds of pears per liter of Carnauba wax was achieved with a solids content of 20%. After the thixotropic aqueous mixture was applied, the Nabaco coated pears and the control pears were stored at room temperature for 5 days and then the degree of superficial scuffing was observed. As shown in Table 1, about 35% of the control pears exhibited severe superficial scuffing and 40%-50% of the control pears exhibited moderate superficial scuffing; whereas less than 10% of the Nabaco coated pears exhibited superficial scuffing. Thus, this test demonstrated that pears coated with the thixotropic aqueous mixture of the present application exhibited reduced superficial scuffing. Figure 5A and Figure 5B

[0111] Example 7

[0112] A packaging line test was conducted on Bartlett pears in which "Nabaco coated" Bartlett pears were coated with a thixotropic aqueous mixture comprising 4.5% bentonite, 1.32% gum arabic, and 0.18% sodium citrate (% values by weight of total composition) as compared to control Bartlett pears coated with Carnauba wax. The thixotropic aqueous mixture was applied to the Nabaco coated pears using a spray bar and brush bed and an application rate of 7000 pounds of pears per liter of thixotropic aqueous mixture was achieved with a solids content of 4% to 6%. The Carnauba wax was applied to the control pears using a spray bar and brush bed and an application rate of 2500 pounds of pears per liter of Carnauba wax was achieved with a solids content of 20%. After the thixotropic aqueous mixture was applied, the percent of scuffing damage was measured at 1 day, 3 days, 5 days, and 7 days post application. As shown in Table 2, the Nabaco coated pears exhibited a significant reduction in scuffing damage as compared to the control pears. Thus, this packaging line test demonstrated that pears coated with the thixotropic aqueous mixture of the present application exhibited reduced superficial scuffing. Figure 6

[0113] Example 8

[0114] ​​A packing line test was performed on D'Anjou pears, in which "Nabaco coated" D'Anjou pears were coated with a thixotropic aqueous mixture comprising 4.5% bentonite, 1.32% gum arabic, and 0.18% sodium citrate (% values by weight of total composition) compared to control D'Anjou pears coated with a coating of carnauba wax. The thixotropic aqueous mixture was applied to the Nabaco coated pears using a spray bar and brush bed and an application rate of 7000 pounds of pears per liter of thixotropic aqueous mixture was achieved, with a solids content of 4-6%. The carnauba wax was applied to the control pears using a spray bar and brush bed and an application rate of 2500 pounds of pears per liter of carnauba wax was achieved, with a solids content of 20%. The percent rub damage was measured 1 day, 3 days, 5 days, and 7 days after application of the thixotropic aqueous mixture. As shown in Table 1, the Nabaco coated pears exhibited a significant reduction in rub damage compared to the control pears. Thus, this packing line test demonstrates a reduction in russeting of pears coated with the thixotropic aqueous mixture of the present application. Figure 7

[0115] The terms "comprising," "including," and "having" as used in the claims and specification herein shall be considered as specifying open-ended claims and shall not be considered as excluding the presence of zero or more additional elements. The terms "a," "an," and the singular forms of words shall not be construed as excluding the plural unless expressly so indicated. The terms "one" and "the" as used in the claims and specification herein shall not be construed as excluding the presence of more than one element unless expressly so indicated. The term "about" as used in the claims and specification herein shall be considered to be equivalent to the term "approximately." The terms "preferably," "preferred," "prefer," "optionally," "may," and the like as used herein are not by way of limitation, but rather mean that various embodiments of the application have been found to work particularly well.

[0116] The present application has been described with reference to various particular and preferred embodiments and techniques. However, it should be understood that many variations and modifications can be made while remaining within the spirit and scope of the application. It will be apparent to those ordinary skill in the art that methods, devices, device elements, materials, procedures and techniques other than those specifically described herein can be employed in the practice of the present application without resorting to undue experimentation. All such alternative implementations are intended to fall within the scope of the present application. Whenever a numerical range is disclosed, it is meant to include all subsets of said range. The application is not to be limited by the embodiments disclosed in the figures or exemplified in the examples, which are given by way of example and not of limitation. The application is to be limited only by the claims.

[0117] ​While the application has been described with respect to a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the application disclosed herein. Accordingly, the scope of the application should be limited only by the appended claims.

[0118] All references, such as patent literature (including published or issued patents or equivalents), patent application publications, and non-patent literature documents or other source materials, in this application are incorporated by reference herein in their entirety to the extent that they are not inconsistent with the disclosure herein (e.g., a part not inconsistent with the disclosure herein is incorporated by reference, in addition to the part that is not inconsistent with the disclosure herein).

Claims

1. A thixotropic aqueous mixture for protecting agricultural products from abrasion damage and / or tiger scab damage, comprising at least one montmorillonite clay and a water-soluble polymer.

2. The thixotropic aqueous mixture according to claim 1, wherein the at least one montmorillonite clay is 1 wt.% to 7 wt.%, optionally 2 wt.% to 6 wt.%.

3. The thixotropic aqueous mixture according to claim 1 or claim 2, wherein the at least one montmorillonite clay is montmorillonite, bentonite, lithium montmorillonite, or lithium saponite; or a mixture of any two or more thereof.

4. The thixotropic aqueous mixture according to claim 3, wherein the at least one montmorillonite clay is sodium montmorillonite or bentonite.

5. The thixotropic aqueous mixture according to any one of claims 1 to 4, wherein the at least one montmorillonite clay is hydrophobically modified.

6. The thixotropic aqueous mixture according to any one of claims 1 to 5, wherein the water-soluble polymer is gum arabic or pectin.

7. The thixotropic aqueous mixture according to any one of claims 1 to 6, wherein the water-soluble polymer is 0.5 wt.% to 5.0 wt.%, optionally 1 wt.% to 2.5 wt.%.

8. The thixotropic aqueous mixture according to any one of claims 1 to 7, wherein the ratio of at least one montmorillonite clay to the water-soluble polymer is 1:4 to 4:1; optionally, the ratio of at least one montmorillonite clay to the water-soluble polymer is about 1:

1.

9. The thixotropic aqueous mixture according to any one of claims 1 to 8, further comprising an antioxidant.

10. The thixotropic aqueous mixture according to claim 9, wherein the antioxidant is sodium citrate.

11. The thixotropic aqueous mixture according to claim 9 or claim 10, wherein the antioxidant is 0.05 wt.% to 0.5 wt.%.

12. The thixotropic aqueous mixture according to claim 9, wherein the antioxidant is an antioxidant oil, optionally squalene.

13. The thixotropic aqueous mixture according to any one of claims 1 to 12, further comprising a solvent.

14. The thixotropic aqueous mixture of claim 13, wherein the solvent comprises or is composed of water; optionally, wherein the solvent comprises a mixture of water and ethanol.

15. The thixotropic aqueous mixture according to any one of claims 1 to 14, wherein the aqueous thixotropic mixture is an aqueous colloidal dispersion containing 1% to 7% solids.

16. The thixotropic aqueous mixture according to any one of claims 1 to 15, wherein the mixture is organic.

17. A method for preparing a thixotropic aqueous mixture, comprising mixing at least one montmorillonite clay and a water-soluble polymer with a solvent under high shear to form a thixotropic mixture.

18. The method of claim 17, wherein the solvent comprises or is composed of water; optionally, the solvent comprises a mixture of water and ethanol.

19. The method according to claim 17 or claim 18, wherein the at least one montmorillonite clay is montmorillonite, bentonite, lithium montmorillonite or lithium saponite, or a mixture of two or more thereof; optionally, wherein the at least one montmorillonite clay is sodium montmorillonite or bentonite; optionally, wherein the at least one montmorillonite clay is hydrophobically modified.

20. The method according to any one of claims 17 to 19, wherein the water-soluble polymer is gum arabic or pectin.

21. The method according to any one of claims 17 to 20, wherein the at least one montmorillonite clay and the water-soluble polymer are combined in powder form, and then the combined powder is mixed with a solvent under high shear.

22. The method according to any one of claims 17 to 20, wherein the at least one montmorillonite clay and the water-soluble polymer are respectively added to the solvent during high-shear mixing.

23. The method according to any one of claims 17 to 22, further comprising mixing the antioxidant with the at least one montmorillonite clay and the water-soluble polymer in the solvent under high shear.

24. A thixotropic composition prepared by any one of claims 17 to 23.

25. A method comprising: i) Prepare a thixotropic mixture using the method according to any one of claims 17 to 23; and ii) Apply the thixotropic aqueous mixture to the surface of agricultural products by means of an impregnation tank, spray bar, or brush bed, or any combination thereof.

26. A method for protecting agricultural products from abrasion damage, comprising applying a thixotropic aqueous mixture according to any one of claims 1 to 16 or 24 to the surface of the agricultural product.

27. A method for protecting agricultural products from tiger skin disease damage, comprising applying a thixotropic aqueous mixture according to any one of claims 1 to 16 or 24 to the surface of the agricultural product.

28. The method of claim 26 or 27, wherein the thixotropic aqueous mixture is applied by an impregnation tank, a spray bar, or a brush bed, or any combination thereof.

29. The method of claim 25 or 28, wherein the thixotropic aqueous mixture is applied using a combination of a spray bar and a brush bed or a combination of an immersion tank and a brush bed.

30. The method of any one of claims 25, 28 or 29, wherein the spray bar applies the thixotropic aqueous mixture to the agricultural products at a spraying rate in the range of 3,000 to 7,000 pounds of agricultural products per liter of thixotropic aqueous mixture.

31. The use of the thixotropic aqueous mixture according to any one of claims 1 to 16 or 24 for protecting agricultural products from abrasion damage.

32. The use of the thixotropic aqueous mixture according to any one of claims 1 to 16 or 24 for protecting agricultural products from tigerskin disease damage.

33. The method according to any one of claims 25 or 26 to 30, or the use according to claim 31 or 32, wherein, The agricultural product in question is fruit; optionally, it is a pome fruit.

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