FIELD

The present disclosure relates to a method and a system for decontamination of agricultural product.

DEFINITION

As used in the present disclosure, the following term is generally intended to have the meaning as set forth below, except to the extent that the context in which it is used indicates otherwise. Agricultural product: The term "agricultural product" refers to agricultural products that are raw, such as cereals, grains, fruits, nuts, spices, vegetables, as well processed food products.

BACKGROUND

Agriculture/food products consumed worldwide continue to pose challenges for the fast growing food industry due to the presence of an array of contaminants in these foods. These contaminants reduce the shelf life of food products and additionally pose severe health hazards for the consumers.

New technologies for food treatment and sanitization are being developed with different devices/ systems and processes employing variety of sanitizing mechanisms for removal of food contaminants Recently, trioxygen has been the catch of the industry owing to its attractive 'high elimination and no residues post treatment' properties. Various techniques are known for utilizing trioxygen for food sanitization. One of the techniques employs treating food products in divided form while maintaining continuous flow of food products in and out of a pressurized trioxygen chamber in order to de-bacterize the food substance effectively. The process treats food products in a continuous manner in distributed form wherein the food product is conveyed through trioxygen atmosphere by vibrating the device. The process is suggested to treat the food substance in one single passage through the treatment enclosure. Another technique employs batch process for treatment of grains employing discontinuous flow of grains in chamber injected with predetermined concentration of Trioxygen. This process is designed specifically for production of technological flours wherein wheat grains are pretreated prior to milling. Still another process uses a treatment rate of 0.5 to 20 g Trioxygen per kg grains along with a pressure of 0.2 to 0.8 bar and moisture up to 15 - 17% of grain weight. The process separates the pericarp of wheat grains yielding a fraction rich in fibers. Separation of pericarp during the process is suggested to further reduce energy and cost inputs for milling of grains and imparts considerable control over flour properties.

However, a major aspect of food treatment involves retaining all the original organoleptic characteristics of the food product under treatment. Known technologies of food sanitation using trioxygen do not incorporate organoleptic assessment of foods, an aspect bearing direct implications to the success of the technologies.

Therefore, there is felt a need for a method for decontamination food products that of mitigates the hereinabove mentioned drawbacks. OBJECTS

Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative. An object of the present disclosure is to provide a method for decontaminating an agricultural product.

Another object of the present disclosure is to provide a method for decontaminating an agricultural product in its dry form.

Still another object of the present disclosure is to provide a system for decontaminating an agricultural product in dry form and in short period of time.

Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure. SUMMARY

The present disclosure provides a method for decontamination of agricultural product for elimination of contaminants and enhancement of self-life. Decontamination is done by exposing the agricultural product to a combination of trioxygen and ultraviolet light radiation. The method comprises the steps of providing a decontamination chamber, placing the agricultural product in the decontamination chamber, vacuuming the decontamination chamber, introducing trioxygen in the decontamination chamber, and subjecting the agricultural product to UV radiations for predetermined time at a predetermined temperature.

The present disclosure further provides a decontamination system for agricultural product. The system comprises a decontamination chamber for placing the agricultural product to be treated, a trioxygen generator for trioxygen generation, a vacuum pump for removing air from the decontamination chamber, UV irradiation chamber, a means for introducing trioxygen gas in the decontamination chamber, and a trioxygen destructor for converting unused trioxygen into oxygen. The decontamination chamber has conveying means selected from rotational, vibratory, oscillatory, anti-gravity, sliding means, and any other movement that may be required for various products.

Agricultural products including whole grains, seeds, nuts, spices, fruits, dried green leafy vegetables, herbs and grasses, packaged foods can be decontaminated using the method of the present disclosure. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

The disclosure will now be described with the help of the accompanying drawing, in which:

Figure 1 illustrates a schematic representation of a system for decontaminating an agricultural product in accordance with the present disclosure.

LIST OF REFERENCE NUMERALS

100 - Decontamination system

102 - Decontamination chamber

102 a - Inlet Temperature gauge

Pressure gauge

Vertical apparatus

Tri-oxygen generator Pressure gauge

Ammeter

Flow meter

Current control switch Oxygen cylinder

Pressure gauge

Hot air compressor

Pressure gauge

Temperature gauge

Vacuum Pump

Trioxygen destructor Pressure gauge

UV irradiation chamber UV source

Dry-heat exposure chamber Agricultural product feed line Oxygen line

Control valve on line 122 Tri-oxygen line ( from tri-oxygen generator)

Control valve on line 124

Hot air line from (from hot air compressor)

Control valve on line 126

Line to decontamination chamber

Control valve on line 128

Tri-oxygen treated agricultural product line (from decontamination chamber to UV irradiation chamber)

UV treated agricultural product line(from UV irradiation chamber to dry heat exposure chamber)

Decontaminated agricultural product

Tri-oxygen line from decontamination chamber to tri-oxygen destructor Control valve on line 142 Air inlet Vacuum line Oxygen outlet

DETAILED DESCRIPTION

Conventional decontamination methods for agricultural product still lack the ability for decontaminating the agricultural product in their dry form. Therefore, the scaling up of the technology already developed remains a challenge to solve practical problems of agriculture sector.

Further, the time required in conventional methods for decontamination of agricultural products with trioxygen is around 96 hour which is not economically feasible. Dislodging trioxygen or trioxygen smell also becomes difficult due to such long decontamination hours. Organoleptic properties and nutritional properties of the treated product should not deteriorate with such long exposure of trioxygen. Various problems need to be addressed when agricultural products are treated with trioxygen. The decontamination process should be as effective at commercial level. It should be provided with safe removal of trioxygen waste, prevention of overheating and pressure buildup and use optimum trioxygen. The decontamination should be safe, environmental friendly, efficient, and cost effective trioxygen decontamination systems, methods or devices that would partially or totally eliminate fat soluble secondary fungal metabolites illustrated in Table- 1, and microorganisms from food for human consumption.

Table 1 : Fat soluble secondary fungal metabolites

In accordance with the present disclosure, a decontamination method and system for agricultural product is envisaged to overcome the abovementioned drawbacks.

The present disclosure in an aspect of provides a system (100) for decontaminating an agricultural product. The system (100) as illustrated in Figure-1 comprises the following: a trioxygen generator (106) configured to receive oxygen from oxygen cylinder (108) to provide trioxygen gas via line (124) made up of silicon tubes to the decontamination chamber (102);

the trioxygen generator (106) is provided with a pressure gauge (106 a) ammeter (106 b), a flow meter (106 c), and a current control switch (106 d);

the oxygen cylinder (108) is provided with a pressure gauge (108 a);

a decontamination chamber (102) configured with an inlet (102 a) to receive the agricultural product via agricultural product feed line (120) and trioxygen at a predetermined flow rate from the trioxygen generator (106);

- the decontamination chamber (102) is further provided with a temperature gauge

(102 b) and a pressure gauge (102 c);

a UV irradiation chamber (116) configured to receive the agricultural product from the decontamination chamber (102) and further configured with a UV source (116 a) to facilitate irradiation of the agricultural product with UV radiation; and a dry heat exposure chamber (118) configured to receive agricultural product from the UV irradiation chamber (116) and further configured to facilitate heating of the agricultural product received from the UV irradiation chamber (116).

The system (100) comprises a hot air compressor (110) configured to receive air via air inlet (138) and to provide hot air to the decontamination chamber (102). The hot air compressor (110) is provided with a pressure gauge (110 a) and a temperature gauge (110 b).

A vacuum pump (112) is configured to the system (100) to reduce pressure of the decontamination chamber (102) via vacuum line (140).

In order to maintain desired temperature and pressure in the system (100), pressure gauges (102 c) (106 a) (108 a) (110 a) (114 a) and temperature gauges (102 b) (110 b) are disposed in the system (100) to operate the control valves.

The system (100) comprises a control valve (122 a) on oxygen line (122), a control valve (124 a) on trioxygen line (124), a control valve (126 a) on hot air line (126), control valve (128 a) on line (128), control valve (126 a) on hot air line (126), and control valve (136 a) on unused trioxygen line (136). The decontamination chamber (102) of the system (100) includes conveying means such as rotating, vibrating, oscillating, anti-gravity, and sliding means.

The present disclosure in another aspect provides a method for decontamination an agricultural product. The process comprises introducing an agricultural product into a decontamination chamber (102) via an inlet (120). Trioxygen at a predetermined flow rate having a predetermined concentration is introduced into the decontamination chamber (102) for a first predetermined time period to obtain trioxygen treated agricultural product.

The system (100) is capable of on-site generation of trioxygen from pure (¾ or air, for eliminating trioxygen storage and loss of excessive trioxygen during storage.

In accordance with the embodiments of the present disclosure, the first predetermined time period can be in the range of 10 minutes to 2 hours.

Typically, the predetermined flow rate of trioxygen can be in the range of 10 1pm to 200 1pm and the predetermined concentration can be in the range of 50 g/h to 750 g/h.

In an embodiment, the unused trioxygen gas from the decontamination chamber (102) is led to a trioxygen destructor (110) for converting trioxygen to oxygen. In another embodiment, the agricultural product to be decontaminated is heated to a temperature in the range of 40 °C to 85 °C for a time period in the range of 10 minutes to 2 hours in the decontamination chamber (102) prior to being treated with trioxygen.

In still another embodiment, vacuum up to 750 mm Hg can be applied to the decontamination chamber (102) to remove air, prior to introducing trioxygen to the decontamination chamber (102).

The trioxygen treated agricultural product is transferred from the decontamination chamber (102) to a UV irradiation chamber (116) and irradiated with UV radiation for a second predetermined time period to obtain treated agricultural product. The typical wavelength used for the UV radiation can be in the range of 250 nm and 370 nm.

In accordance with the embodiments of the present disclosure, the second predetermined time period can be in the range of 10 minutes to 2 hours.

The treated agricultural product is transferred from the UV irradiation chamber (116) to a dry-heat exposure chamber (118), and heated to a predetermined temperature for a third predetermined time period to obtain decontaminated agricultural product. Typically, the predetermined temperature can be in the range of 40 °C to 85 °C. Typically, in accordance with the present disclosure, the method can be carried out as a batch, continuous and semi continuous process.

In accordance with the present disclosure, the agricultural product is an agricultural crop selected from the group consisting of leafy vegetable crops, legume crops, annual fruit crops, and perennial fruit crops.

Typically, but not limited to, the following can be decontaminated using the method of the present disclosure: whole grains, such as rice, wheat, corn, rye, barley, durum, quinoa; - edible seeds, such as egusi seeds, melon seeds, watermelon seeds, sunflower seeds, pumpkin seeds; nuts, such as groundnuts/ peanuts, tiger nuts, pecans, pistachios, hazelnut, walnut, almonds, brazil nut; spices, such as pepper (red and black), cardamom, cinnamon, cloves, nutmeg, cumin and coriander, turmeric, ginger, fennel, marjoram, anise, caraway, peppermint; and herbs and grasses, such as lemon grass, sumac, chamomile, bay leaf, sage, basil seeds, thyme mint, betel leaves. The time and the temperature of the decontamination typically depend upon the moisture content, texture, and nature of the agricultural product to be decontaminated. The original organoleptic properties of the products treated are retained using the method of the present disclosure.

The method of the present disclosure is capable of decontaminating an agricultural product from a contaminant selected from the group consisting of fungal metabolites, bacteria, fungi, yeast, pathogenic microorganism and insect. Live/adult insects, such as weevil can be eliminated and also the proliferation of weevil eggs post treatment over time can be achieved using the method of the present disclosure.

The decontamination system (100) disclosed in the present disclosure detoxifies fungal metabolites as well as decontaminates microorganisms from agricultural product. Trioxygen on reaction with a contaminant gets converted to (¾, a harmless gas, ensuring environmental friendliness of the decontamination and safe agricultural product.

The method of the present disclosure uses Trioxygen atmosphere for treating the various products. The moisture of the products can be adjusted using hot air treatment at pre- determined temperature.

The method of the present disclosure is capable of decontaminating a wide range of fungal metabolites, bacteria, and insects. The products treated in accordance with the method of the present disclosure are capable of retaining the original organoleptic properties. During the decontamination of food product, the trioxygen gas oxidizes the contaminants and converts to (¾. The method of the present disclosure is rapid, and is effective in treating a wide range of contaminants including fungal metabolites, bacteria, fungi, yeast, pathogenic microorganisms, and insects, such as weevil. The method of present disclosure is capable of eliminating live weevil as well as delay the proliferation of weevil eggs post treatment. Further, the method of the present disclosure is viable and can be easily scaled to a commercial level. The present disclosure is further described in the light of the following experiments. Experiments are set forth for illustration purpose only, which are not to be construed for limiting the scope of the disclosure. The following laboratory experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial/commercial scale.

Experimental Details

Experiment- 1: Decontamination of whole red chilli using the method and system of the present disclosure

This experiment illustrates the treatment of aerobic micro-organisms, yeast, mould, coliform, E. coli, Salmonella and fat soluble metabolites contaminated whole red chilli.

The data presented in table 2 illustrate the efficacy of the present disclosure in detoxifying contaminated whole red chillies. Four sets of whole red chilies of 25 g, 3 kg, 5 kg, and 10 kg were separately decontaminated in the decontamination system. 25 g whole red chillies naturally contaminated with aerobic micro-organisms, yeast, mould, coliform, E. coli and Salmonella were decontaminated in the decontamination system of the present disclosure. The red chillies were exposed with trioxygen for up to 6 hours. Trioxygen gas having a capacity 2 g/h was generated by the trioxygen generator on site with a constant oxygen flow rate and delivered to the decontamination chamber through silicon tube. The whole red chillies were then exposed to UV rays of wavelength 253.7 nm up to 2 hours. The whole red chillies were then treated to a heated temperature of up to 85 °C for up to 2 hours. Similarly, C17H12O6 contaminated 3 kg, 5 kg, and 10 kg of whole red chillies were decontaminated in the decontamination system. All the treated products were heated and then analyzed for the presence of the contaminant and the result obtained are summarized in Table-2.

Table-2:

3 25 g Coliform Count 2.31 x 10 ⁴ < 10

4 E.coli Present / g Absent / g

5 Salmonella Present / 25 g Absent / 25 g

6 3 kg C17H12O6 2196.98 0.116 mcg/kg

mcg/kg

7 5 kg C17H12O6 487.49 mcg/kg Not detected

8 10 kg C ₁₇ H ₁₂ 0 ₆ 487.49 mcg/kg Not detected

It is seen from Table-2, that there is a significant decrease in the contamination using the system and the method of the present disclosure. Further, the original organoleptic properties of the whole red chilli were retained after the treatment. Experiment-2: Decontamination of groundnuts using the method and system of the present disclosure

The data presented in Table-3 illustrates the efficiency of the method and system of the present disclosure in detoxifying contaminated groundnuts. Three sets of C17H12O6 contaminated 25 g, 3 kg, and 3 kg of groundnuts were separately decontaminated in the decontamination system of the present disclosure. 25 g groundnuts spiked with fat soluble metabolite C17H12O6 were decontaminated in the decontamination system. In this case, groundnuts were heated before the exposure of the product with trioxygen for up to 6 hours. Trioxygen gas having capacity 2 g/h was generated by the trioxygen generator on site with a constant oxygen flow rate and delivered to the decontamination chamber through silicon tube. The groundnuts were then exposed to UV rays of wavelength 253.7 nm up to 2 hours. The groundnuts were then heated to a temperature of up to 85 °C for up to 2 hours. The remaining two sets of C17H12O6 contaminated groundnuts (3 kg) were decontaminated in decontamination system. All 3 sets of product were heated and then analyzed for the presence of the contaminant and the results obtained are summarized in Table-3. Table-3

1 25 g C17H12O6 103.1 mcg/kg 41.89 mcg/kg

2 3 kg C17H12O6 101.84 mcg/kg 2.81 mcg/kg

3 3 kg C17H12O6 101.84 mcg/kg 1.77 mcg/kg

It is seen from Table-3 that the method of the present disclosure employing trioxygen in combination with UV and heat is capable of effectively degrading C17H12O6 in groundnuts. There was no change in the organoleptic properties in the groundnut after the treatment. Experiment-3: Decontamination of nutmegs using the method and system of the present disclosure

The data presented in Table-4 illustrates the efficiency of the present disclosure in detoxifying contaminated nutmegs. Two sets of nutmegs (3 kg and 18 kg) contaminated with C17H12O6 were separately decontaminated in the decontamination system of the present disclosure as described in experiment-2, and the results obtained are summarized in Table-4.

Table-4:

It is seen from Table-4 that the system and the method of the present disclosure is capable of reducing the contamination in nutmeg. Also, there is no change in the organoleptic properties in the nutmeg that was subjected to the treatment.

Further experiments were conducted using grains such as whole wheat, rice and dry maize and were treated as per the above experiments to eliminate weevils and delay insect infestation. It was observed that the in comparison with an untreated control weevil infestation was substantially delayed by over a period of 4 to 7 months using the method and system of the present disclosure.

It can be concluded from the foregoing that the method of the present disclosure reduces contamination and increases safety and shelf life of the agricultural products. The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCEMENTS

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a method and a system for decontaminating an agricultural product. The method of the present disclosure increases the safety and the shelf life of the treated agricultural product and at the time retains the original organoleptic properties of the agricultural product that is treated. Further, the method of the present disclosure is rapid and effective and is can be scaled to a commercial level.

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention. The numerical values given for various physical parameters, dimensions, and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary. While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.