WO2021214782A1

WO2021214782A1 - A packaging composite and the process for preparing such composite

Info

Publication number: WO2021214782A1
Application number: PCT/IN2020/050504
Authority: WO
Inventors: Jayant Rajaram Pawar; Rohit Ghugare; E.A. Singh
Original assignee: Jayant Rajaram Pawar
Priority date: 2020-04-20
Filing date: 2020-06-08
Publication date: 2021-10-28
Also published as: ZA202212415B

Abstract

"Disclosed is a packaging composite comprises of a first layer, a second layer and a third layer, the second layer being laminated by the third layer; wherein, the first layer is made up of polyethylene terephthalate; the second layer is made up of ethylene-vinyl acetate; the third layer is made up of metal-oxide particles; wherein amount of the ethylene-vinyl acetate is 34% by weight; amount of the polyethylene terephthalate is 44% by weight; and amount of the metal-oxide particles is 22% by weight. Also provided is a method of manufacturing the composite".

Description

A PACKAGING COMPOSITE AND THE PROCESS FOR PREPARING

SUCH COMPOSITE

FIELD OF THE INVENTION

The present invention relates to a packaging system. More particularly, the present invention relates to a packaging composite comprises of a special combination of polymeric matrix and metal oxide nano-filler and also relates to a process for preparing such composite.

BACKGROUND OF THE INVENTION

Traditionally, food packaged in a material, which has passive barriers designed to delay the adverse effect of the environment. In the industry, food product is packed using a variety of conventional packaging materials such as trays, bags, boxes, cans, cartons, sheets, pallets and wrappers made of plastic, metal, ceramic, glass and paper. There is a growing need to protect stored food using suitable packaging material which serves to be safe under its intended conditions of use and should be inert, cheap to produce, light weight, easily degradable, reusable, able to persist in extreme conditions during processing, storage, transport conditions and resistant to physical abuse. The packaging expected to protect food from dirt or dust, oxygen, light, pathogenic, food spoiling microorganisms, moisture as well as other destructive and harmful substances. However, in addition to performing the above tasks expected from a packaging material advanced packaging should inhibit the microorganisms responsible for food spoilage and poisoning.

In this context, a single packaging material cannot offer all the vital properties therefore; it can achieve by merging different packaging materials into a multi-layer packaging film. Multi-layer film is the combination of two or more polymers and possibly metallic foil, paper etc. into a composite to provide functional, shielding and decorative properties. Such packaging are used to provide customized properties of each polymer in combination, which includes barrier (to light, moisture and gases) properties, seal ability, chemical resistance, strength, rigidity and stiffness that would otherwise be very difficult to achieve with a single polymer. However, multi-layer film packaging has created a global environmental issue related to its waste. Since, multi-layer films have number of components; it is very difficult to recycle and hence must have separated before recycling.

Despite the numerous advantages offered by polymers in food packaging, the present scenario of food industry demands the path breaking approach where the polymers not only perform the passive role of food packaging, but also they must actively participate in food stability by killing the microbes responsible for spoilage, controlling migration of gases and moisture into food. The need also exists in the art is to provide an approach that could protect the food for a longer period.

A non-patent literature ( Silvestre C, Duraccio D & Cimmino S (2011) Food packaging based on polymer nanomaterials. Prog. Polym. Sci., 36: 1766- 1782 ) reveals that that any material intended for food contact must be suitable, inactive and able to avoid the substances which can be transferred to products in quantities harming human health or bringing about an unacceptable change in food composition or properties. Although, the existing packaging composite have emerged as an attractive alternative to preserve food quality, extend shelf- life, and prevent microbial spoilage, it allows direct exposure of nanomaterials to humans due to leakage from packaging material into the food substance and the food substance is therefore not at all safe in such existing packaging composite. Therefore the need exists in the art is to provide a packaging composite with no leakage problem.

In another non-patent literature [Pawar, Jayant & Kunchiraman, Bipinraj & Singh, E. & Nikam, Nikhil. (2012). Determination and Partial Characterization of Antimicrobial Material of Pseudomonas aeruginosa Isolated from Milk. Research & Reviews: A Journal of Food Science & Technology. 1. 16-23], owing to rapid increase of resistance in pathogenic and food spoiling microorganisms for numerous traditional antimicrobials, it is mandatory to find out suitable alternatives. Inorganic nanoparticles are found to be more advantageous due to their easy dispersion into the polymer matrix to form functional antimicrobial packaging nanocomposite which may remain as biocidal material for a long period of time (Duncan, T. V. (2011). Applications of nanotechnology in food packaging and. food safety: barrier materials, antimicrobials and sensors. Journal of colloid and interface science, 363(1 ), 1-24.). Furthermore, lesser amount of nano-sized antimicrobial materials in polymer evinces greater efficiency against microorganisms as compared to large quantity of micro-sized counterparts (Armentano, L, Arciola, C. R., Fortunati, E , Ferrari, D., Mattioli, S., Amoroso, C F , ... & Visai, L. (20141. The interaction of bacteria with engineered nanostructured polymeric materials: a review. The Scientific World Journal, 2014). Carbon nanofillers like CNTs, Graphene, Graphene Oxide etc. has used in many packaging composites to improve the polymer properties such as antimicrobial, physical, mechanical, thermal and electrical properties, which makes it attractive alternatives for traditional fillers. For instance, MWCNTs (multi- walled carbon nanotubes) were used as an antimicrobial agent in the hyperbranched polyurethane (HBPU) (Yadav, S. K , Mahapatra, S. S., & Cho, J. W. (2012). Synthesis of mechanically robust antimicrobial nanocomposites by click coupling of hyperbranched polyurethane and carbon nanotubes. Polymer, 53(10), 2023-2031.). But the biggest disadvantages, for the use of carbon nanofillers in such polymers, are its intrinsic zero band-gap energy and low solubility in organic and aqueous solvents (Jamroz, E., Kulawik, P., & Kopel, P. (2019). The effect of nanofillers on the functional properties of biopolymer-based films: A review . Polymers, 11 (4) , 675.), which leads to create problem in uniform distribution and in contact inhibition of the microorganisms present in packet.

Therefore, there is a need to overcome the drawback of the existing technologies.

OBJECT OF THE INVENTION

It is an objective of the invention is to provide a packaging composite.

It is another objective of the present invention is to provide a packaging composite which could protect the food and other goods for a longer period.

It is yet another objective of the present invention is to provide a packaging composite that could provide broad-spectrum antagonistic activity against bacteria, fungus, algae etc.

It is yet another objective of the invention is to provide a packaging system which could protect the food from a wide variety of microorganisms in particular Schizosaccharomyces pombe, Torulaspora delbrueckii, Debaryomyces hansenii, Candida krusei, Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes or Serratia marcescens.

It is yet another objective of the invention is to provide a packaging system which could protect the different type of food in particular, a solid food, a semi-solid food or a liquid food.

It is yet another objective of the invention is to provide a packaging composite which could solve the existing leakage problem. It is yet another objective of the invention is to provide a packaging composite wherein the metal oxide nano-particle is non-carbon in origin, biocompatible and safe.

It is yet another objective of the invention is to provide a process for preparing the composite.

SUMMARY OF THE INVENTION

According to one aspect of the invention, there is provided a packaging composite comprises of a first layer, a second layer and a third layer, the second layer being laminated by the third layer and the said laminated layer being positioned towards a substance placed inside the said composite; wherein, the first layer is made up of polyethylene terephthalate; the second layer is made up of ethylene-vinyl acetate; the third layer is made up of metal-oxide nanoparticles; wherein the amount of ethylene-vinyl acetate is 34 % by weight; the amount of polyethylene terephthalate is 44% by weight; the amount of metal-oxide nanoparticles is 22% by weight.

According to another aspect of the invention, there is provided a process for preparing the composite, the said process comprising the steps of i) preparing a film which comprises of an first layer and an second layer wherein the first layer being made up of polyethylene terephthalate and the second layer being made up of ethylene-vinyl acetate; ii) spreading the metal oxide nanoparticles onto the second layer of said film of step (i); iii) subjecting the product as obtained in step (ii) into a heating roller at

80-110°C; iv) allowing the product as obtained in step (iii) to cool at room temperature for 2 hours;

In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Figure 1 illustrates the layered arrangement of the packaging composite (PET, EVA & MONs) in accordance with the present invention; Figure 2 illustrates the surface image of PET-EVA-MON film by spray coating technique (2a), CBD technique (2b) and the surface image of PET- EVA-MON film by the spreading & heating technique (2c) in accordance with the present invention;

Figure 3 illustrates the FTIR spectra of the packaging composites wherein 3a is the control (PET & EVA), 3b test composite 1 (PET, EVA & CU2O); 3c is the test composite 2 (PET, EVA & ZnO) & 3d is the test composite 3 (PET, EVA & Mg0₂) in accordance with the present invention;

Figure 4 illustrates the surface morphology of the packaging composites wherein 4a is the control (PET & EVA); 4b is test composite 1 (PET, EVA & CU2O); 4c is test composite 2 (PET, EVA & MgC>2) & 4d is test composite 3 (PET, EVA & ZnO) in accordance with the present invention; Figure 5 is the SEM image of the packaging composites wherein Figure 5a is the Control (PET & EVA); 5b is the test composite 1 (PET, EVA & CU2O); 5c is the test composite 2 (PET, EVA & ZnO) & 5d is the test composite 3 (PET, EVA & MgC>2) in accordance with the present invention. Figure 6 illustrates the UV-Vis transmittance spectra of the various packaging composites in accordance with the present invention; &

Other objects, features and advantages of the inventions will be apparent from the following detailed description in conjunction with the accompanying drawings of the inventions. DETAILED DESCRIPTION OF THE INVENTION

Expression:

PET: polyethylene terephthalate;

EVA: ethylene -vinyl acetate;

“Packaging composite” herein is a system or a device or a tool or a mean to protect a substance (being placed inside the composite) from wide variety of microbes for instance Schizosaccharomyces pombe, Torulaspora delbrueckii, Debaryomyces hansenii, Candida krusei, Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes or Serratia marcescens for a longer duration in particular 8 days; ‘MONs’ or ‘nano-fillers’ or ‘nano-particles’ or ‘nano-composite’ herein is carbon free metal-oxide particles which is used to coat the PET-EVA film; &

‘PET-EVA film’ or a ‘polymeric film’ or ‘polymer matrix’ herein is a film having two layers i.e. first layer and second layer in which the first layer of the film is made up of polyethylene terephthalate (PET) and the second layer of the film is made up of ethylene-vinyl acetate (EVA) . As shown in Figure 1, the present invention provides a packaging composite which comprises of first layer, second layer & third layer. The second layer according to present invention is laminated by a third layer. The laminated layer according to the present invention comes into contact the substance being placed inside the composite. In an embodiment of the invention, the composite itself is a laminated film.

In preferred embodiment of the invention, the first layer is made up of polyethylene terephthalate while the second layer is made up of ethylene- vinyl acetate. The third layer is made up of carbon free metal-oxide nano particles which is biocompatible and safe.

In preferred embodiment, size of the metal oxide nanoparticles is 10-60nm.

In an embodiment of the invention, the metal oxide is selected from a group consisting of copper (I) oxide (CU2O), zinc oxide (ZnO) and magnesium peroxide (Mg02). In preferred embodiment of the invention, the metal oxide is copper (I) oxide

(Cu₂0).

In preferred embodiment of the invention, the amount of EVA is 34% by weight while the amount of PET is 44% by weight and the amount of MONs is 22% by weight. As the metal oxide is herein carbon free, the nano -filler particles would attain the recurring resistance and occurrence of resistant strains is therefore minimized in present invention.

The mass density (a) of the metal-oxide particles according to the present invention is 125. As the coating of the PET-EVA film by the nano-fillers according to present invention is done through a lamination technique (spreading and heatng), the present invention reduces the chance of leakage.

In an embodiment of the invention, the substance being placed inside the packaging composite for protection is food products or other goods.

In preferred embodiment of the invention, the substance is a food product.

In an embodiment of the invention, the food product is selected from a group consisting of solid, semi-solid or liquid.

In an embodiment of the invention, the liquid food product is milk. In an embodiment of the invention, the substance is cement, cloths, or medicines.

The packaging composite according to present invention is prepared by a lamination technique, the process comprising the steps of: i) preparing a film which comprises of an first layer and an second layer wherein the first layer being made up of polyethylene terephthalate and the second layer being made up of ethylene-vinyl acetate; ii) spreading the metal oxide nanoparticles onto the said film as obtained in step (i); iii) subjecting the product as obtained in step (ii) to a heating roller; iv) allowing the product as obtained in step (iii) to cool at room temperature for 2 hours;

In preferred embodiment of the invention, thickness of the film in step (i) is 177.8 pm. According to the present invention, the spreading (step ii) and the heating (step iii) together is called as “lamination technique”

In preferred embodiment of the invention, the temperature of the heating roller in step (iii) is 118-122°C. It may be noted that the properties like peel strength, tensile strength, cold crystallization and molecular orientation of the laminating film would be hampered if the temperature is above 122 °C. On the other hand, proper lamination would be peeled off if the temperature is below 118°C.

In preferred embodiment of the invention, the pressure in step (iii) is 10-20MPa.

In an embodiment, the present invention provides a food packaging system comprises the aforesaid composite for protection of the food product from various microorganisms.

In preferred embodiment of the invention, the microorganism is selected from a group consisting of Schizosaccharomyces pombe, Torulaspora delbrueckii, Debaryomyces hansenii, Candida krusei, Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes or Serratia marcescens.

The invention is now illustrated by non-limiting examples:

Example 1: The PET-EVA films was prepared as per the hot-pressing method as exemplified in Zhong et ah, Flexible PET/ EVA-based piezoelectret generator for energy harvesting in harsh environments. Nano Energy, 2017, 37, 268-274 except the amount of PET and EVA.

The metal oxide nanoparticles of CU2O, ZnO & MgC>2 were prepared as per the semi-solvo thermal method as exemplified in Jayant Pawar et ah, Application of semi-solvo thermally synthesized zinc oxide (ZnO) nanoparticles in food technology and their characterization, International Journal of Nanotechnology and Applications, Volume 11, Number 1 (2017), pp. 75-80.

Preparation of the packaging composite: Formula A (Inventive formula)

Method: After preparing PET-EVA film using aforesaid quantity (177.8 pm as the thickness), the aforesaid MONs (50nm as the particle size) were spread onto that film and then the product was subjected into a heating roller at 80-110°C wherein the pressure is 10-20 MPa. The product thus obtained was allowed to cool at room temperature for 2 hours. In this method, mass density (a) of the MON particles is 125.

Alternatively, other approaches were applied for coating of MON particles onto the PET-EVA film for instance spraying only (i.e. without the heating step) and chemical bath deposition (CBD) technique. However, it was observed that these coatings are easily deformed upon a slight friction. Also, uniform distribution was not found with these coatings (Figure 2a and 2b). Contrarily, uniform distribution with no distortion was observed with the spreading & heating (lamination) technique (Figure 2 c).

Formula B (Comparative formula):

Comparative Method: After preparing PET-EVA film using aforesaid quantity (177.8 pm as the thickness), the aforesaid MONs (50nm as particle size) were spread onto that film and then the product was subjected into a heating roller at 80-110°C wherein the pressure is 10-20 MPa. The product thus obtained was allowed to cool at room temperature for 2 hours. In this method, mass density (o) of the MON particles is 62.5.

Evaluation of the packaging composites (Formula A & B) : i) Characterization studies:

As shown in Figure 3, the spectra of all PET-EVA-MONs films displayed characteristic peaks in the range of 3500 cm ¹ - 450 cm^-1. The transmittance of the PET-EVA-MONs film decreased as compared to the control (PET-EVA films), which might be due to the interaction of MONs with the polymer matrix. It observed that the transmittance of PET-EVA film was more than the PET-EVA-MONs based film signifying the test films (PET-EVA-MONs) are more opaque when compared with PET-EVA film. The observation made of the control (PET-EVA) and PET-EVA-MONs films under stereoscopic microscope at low magnification, typically using light reflected from the surface of a film to know the uniform distribution of MONs over a PET-EVA film. The uniform distribution of MONs on PET-EVA films was observed under stereomicroscope (Labomed, CZM4) at 400 X magnification (Figure 4). The resultant composite (test composite 1, 2 & 3) showed increased surface roughness as compared to the Control (PET-EVA). The SEM images of PET-EVA-MONs film (test composite 1,2 & 3) also confirmed the distribution of MONs on the PET surface (Figure 5).

As shown in Figure 6, UV-spectra of the control (PET-EVA) and the test composites (PET-EVA-CU₂0 or PET-EVA-ZNO or PET-EVA-MGO2) were analyzed in which the opacity of the nano-composites were observed in the order of PET-EVA-Cu₂0 > PET-EVA-ZnO > PET-EVA-Mg0₂. In case of PET- EVA-CU₂0 film was found with lower transmittance value when compared with control film and other nano-composite films, which may due to its color and large particle size i.e. 50nm absorbs more visible light and does not allow more light to pass through the polymer nanocomposite. Therefore, the transmittance of the nano-composite is inversely proportional to the concentration and uniform distribution of nanofillers onto the matrix, which would help in contact inhibition of microorganisms. ii) Comparative microbial evaluation: To determine the antimicrobial activity of the test composites (PET-EVA- MONs) for both the film A and B, yeasts species viz. Schizosaccharomyces pombe, Torulaspora delbrueckii, Debaryomyces hansenii and Candida krusei and bacterial species viz. Staphylococcus aureus and Bacillus subtilis (Gram positive), Listeria monocytogenes and Serratia marcescens (Gram negative) were selected and the results were tabulated as hereinbelow:

Table 1: Quantitative estimation of antifungal activity of PET/EVA/MONs films against food spoilage yeast cultures by cell count method

Yeast Culture Culture PET/EVA/ PET/EVA/Cu PET/EVA/

Cultures Control with ZnO 2O MgOa normal

(CFU/mL) _fllm Film Film Film Film Film Film

A B A B A B

Schtzosacch 1.489X10⁸ 1.421X10⁸ 4.68 8.93 2.14 3.6 5.1 9.5 aromyces X10⁷ X10⁷ X10⁷ X10⁷ X10⁷ X10⁷ pombe

Torulaspora 3.01 X107 3.76 X107 9.3 1.8 7.15 1.4 1.7 2.1 delbrueckii X10⁸ X1Q7 X10⁸ X1Q7 X1Q7 X1Q7

Debaryomyc 8.995 X10⁷ 8.840 X10⁷ 6.20 3.14 1.155 5.565 1.6 3.1 es hansenii X10⁶ X10⁷ X10⁶ X10⁷ X10⁷ X10⁷

Candida 5.945 X10⁷ 5.825 X10⁷ 9.84 1.50 7.15 4.10 2. IX 5.8 knisei 5X10 X10⁷ X10⁵ X10⁶ 10⁷ X10⁷

6

Table 2: Quantitative estimation of antibacterial activity of PET/ EVA/ MO Ns films against food spoilage bacterial cultures by optical density method at 600 nm _

Bacterial Culture Control PET/ EVA/ PET/ EVA/ C PET/ EVA/

Cultures Control ZnO U2O Mg0₂

(PET-

(CFU/mL) EVA) Film Film Film Film Film Film

A B A B A B

Staphyloc 0.42 0.41 0.19 0.32 0.15 0.28 0.28 0.39 occus aureus Bacillus 0.63 0.60 0.18 0.37 0.16 0.35 0.38 0.53 subtilis

Listeria 0.29 0.30 0.17 0.34 0.14 0.29 0.19 0.26 nvonocytog enes

Serratia 0.56 0.59 021 038 0.17 036 032 0.51 marcescen s

Note: (a) Composition of Film A contains PET (44.44 %), EVA (33.33 %) and MONs (22.22 %); (b) Composition of Film B contains PET (50%), EVA (37.5%) and MONs (12.5%)

With regard to both anti-fungal (Table 1) and anti-bacterial (Table 2) activity, film A corresponding to PET-44%, EVA-34% & MON-22% showed the superior effect over film B (PET-50%, EVA-37.5% & MON- 12.5%). It was also observed that the PET-EVA-CU2O films (A) showed better antibacterial effect against all model microorganisms compared to PET- EVA-ZnO and PET-EVA-MgO_a films. iii) Shelf life of the food product:

To understand the effect of PET-EVA-MONs on shelf life of perishable food product, the pasteurized milk was taken for study. The pasteurized milk was stored into the punnet made out of PET-EVA-MONs and same was tested for spoilage by considering parameters like titratable acidity, organoleptic properties (texture, colour, odour, taste etc.) and total microbial count etc.

Table 3: Evaluation of packaging films by determination of shelf life of milk Packaging Films PET/ EVA/ PET/EVA/ CU₂ PET/ EVA/ Mg

ZnO o 0₂

Test Incubatio Film A Film B Film A Film B Film Film B parameters n Time A

(Days)

Titratable 4 0.140 0.960 0.135 0.925 0.540 0.953

Acidity (%)

8 0.950 ND 0.910 ND ND ND

Organolepti 4 Good Spoile Good Spoile Poor Spoiled c Test d d

8 Spoile Spoile ND ND d ND d ND

Total 4 + ++ + ++ ++ ++

Microbial

8 ++ ND ++ ND ND ND Count

Indication: + : < 10 CFU/mL; ++ : < 50 CFU/mL; ND: Not Determined

Table 4 shows that After extended storage of milk for 8 days at 5°C, we found that the milk stored in the punnet made up of film A (PET:EVA:MONs is 44:34:22) spoiled after 8 days while the milk stored in the punnet made up of film B (PET:EVA:MONs is 50%:37.5%: 12.5%) spoiled after 4 days. It was also observed that the milk stored in the punnet made up of the film PET:EVA:CU₂0 and PET:EVA:ZnO spoiled after 8 days while milk stored in the punnet made up of the film PET:EVA:Mg0₂ spoiled after 4 days.

Principal findings of the invention: i) The higher quantity of the nano -filler (Film A) is required for acheiving two major effects i. anti-microbial properties & ii. Longer protection and the present invention is therefore contrary to the teaching of Arrnentano et al as staled in the background of the invention; ii) As the unexpected effects (as above mentioned) are found at a particular ratio of PET:EVA:MONs (i.e 44:34:22), the present composition is not to he appeared as mere admixture; iii) Non-carbon based nano -fillers are advantageous as the food packaging system is concerned: iii) With regard to the leakage problem, the sprading (step ii) and heating step (iii) jointly [would be appeared as lamination step’] is advantageous.

Although the foregoing description of the present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.

Claims

CLAIMS:

1. A packaging composite comprises of a first layer, a second layer and a third layer, the second layer being laminated by the third layer and the said laminated layer being positioned towards a substance placed inside the said composite; wherein, the first layer is made up of polyethylene terephthalate; the second layer is made up of ethylene -vinyl acetate; the third layer is made up of metal-oxide nanoparticles; wherein the amount of ethylene-vinyl acetate is 34% by weight; the amount of polyethylene terephthalate is 44% by weight; the amount of metal-oxide nanoparticles is 22% by weight.

2. The composite as claimed in claim 1, wherein the metal-oxide particles is carbon-free.

3. The composite as claimed in claim 1, wherein the metal oxide is selected from a group consisting of copper oxide (CU2O), zinc oxide (ZnO) and magnesium peroxide (Mg02).

4. The composite as claimed in claim 1, wherein size of the metal-oxide nanoparticles is 10-60nm.

5. The composite as claimed in claim 1, wherein mass density (o) of the metal- oxide particles is 125.

6. The composite as claimed in claim 1, wherein the said composite is a laminated film.

7. The composite as claimed in claim 1, wherein the substance is a food product.

8. The composite as claimed in claim 7, wherein the food product is selected from a group consisting of solid, semi-solid or liquid.

9. A process for preparing packaging composite comprising the steps of i) preparing a film which comprises of an first layer and an second layer wherein the first layer being made up of polyethylene terephthalate and the second layer being made up of ethylene -vinyl acetate; ii) spreading the metal oxide nanoparticles onto the second layer of said film of step (i); iii) subjecting the product as obtained in step (ii) into a heating roller at 80-110°C; iv) allowing the product as obtained in step (iii) to cool at room temperature for 2 hours; wherein thickness of the film in step (i) is 177.8 pm; wherein temperature of the heating roller in step (iii) is 80-110°C; wherein the pressure in step (iii) is 10-20 MPa; & wherein the metal-oxide particle in step (ii) is carbon-free.

10. A food packaging system comprises the composite as claimed in claim 1 for protection of the food product from a microorganism selected from a group consisting of Schizosaccharomyces pombe, Torulaspora delbrueckii, Debaryomyces hansenii, Candida krusei, Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes or Serratia marcescens.