Description:Field of the invention
The invention leads to formulation of biodegradable natural gum based food packaging material.
Background of the Invention
References which are cited in the present disclosure are not necessarily prior art and therefore their citation does not constitute an admission that such references are prior art in any jurisdiction. All publications, patents and patent applications herein are incorporated by reference to the same extent as if each individual or patent application was specifically and individually indicated to be incorporated by reference.
Several patents have been issued for packaging materials but none of these are related to the present invention. For example, CN109923262B relates to a biodegradable food packaging unit from moulded pulp material and a method for manufacturing such a biodegradable packaging unit. The package according to the invention comprises a food receiving or carrying compartment, wherein the molded pulp material comprises a quantity of biodegradable aliphatic polyester, wherein the food packaging unit is a compostable food packaging unit. In a preferred embodiment, the amount of biodegradable aliphatic polyester is in the range of from 0.5 wt.% to 20 wt.%, more preferably in the range of from 1 wt.% to 15 wt.%.
Another patent, US8382888B2 provides a composition for use in making edible biodegradable containers comprising water, pregelatinized and native starch, a first protein or natural polymeric compound, natural fibers, a wax emulsion, a mold release agent, a flavoring agent, and a coloring agent, wherein the composing consisting essentially of food grade materials.
Another patent, US7951436B2 provides a multi-layer film with barrier properties having one or more layers made from a bio-based film is disclosed. In one aspect, a multi-layer packaging film including(a) an outer layer including a bio-based film, wherein the bio-based film is polyhydroxy-alkanoate, wherein the bio-based film includes a graphic image, (b) an adhesive layer adjacent to the outer layer and (c) a product side layer including a metalized polyolefin having barrier properties, wherein the multi-layer packaging film is a flexible film.
Another patent, CN101899173B provides an edible starch-based food packaging film and a preparation method thereof. The edible starch-based packaging film with high mechanical strength, barrier property, ageing resistance and heat sealability is prepared from a main film-forming raw material stabilized crosslinking compound modified starch, and auxiliary materials such as food grade plasticizers, lubricants, reinforcers, stabilizers and the like through high speed stirring and mixing, twin-screw extrusion granulation and single-screw extrusion blow molding. The preparation method has the characteristics of low energy consumption, high production efficiency and suitability for continuous industrialized production. The film has the advantages of edibility, full-degradable property, wide application for inner packaging of foods and no environmental pollution caused by non-degradable food packages.
Another patent, EP1369227B1 provides biodegradable bags for packing foods comprising a laminate film composed of a sealant layer made of a biodegradable polymer, a barrier layer capable of blocking oxygen/vapor and a barrier layer-supporting layer made of a biodegradable polymer, wherein these layers are laminated in this order and heat-sealed so that the sealant layer is located inside. It is intended to provide biodegradable bags for packing foods capable of blocking oxygen/vapor, characterized in that these bags are available in the production at a high speed with a packing machine, spontaneously degraded by microorganisms in soil or water, can be biologically recycled and are not accumulated in nature.
In today’s fast developing world scenario, industrial symbiosis within synthetic plastic supply chain leads to an increasing amount of non-biodegradable waste consisting of synthetic polythene, plastic bags, packaging bags, which is invaluable and toxic to the soil and cannot be reused or recycled. Presently, plastics are most demanding as they exhibit many worthwhile characteristics, such as: transparency, softness, heat seal-ability, and good strength to weight ratio. They are generally low-cost materials, show efficient mechanical properties such as tear and tensile strength, and they are good barrier to oxygen and heat. On the contrary, most of the plastic food packaging materials have raised a serious global environmental problem.
Di?erent types of polymers have been used other than polysaccharide based by researchers for producing packaging films. Films are pre-formed independent structures that wrap or cover horticultural produce. These are either applied to horticultural produce or formed directly on produce that is intended to be protected. Packaging material are in film form on products, ordinarily by immersing the natural gum of structural matrix forming substances such as carbohydrate, protein, lipid, or different compositions of it.
Keeping the above facts in mind and by using anthropometric data of people, there is a need to develop an ecofriendly material for packaging that would be helpful for the people. It should have the more strength and least non-uniform packaging material. It was developed for both food and nonfood products.
Development of a packaging film for food material which is the basic and important post-harvest operation for removal of non-biodegradable synthetic plastic from the world use. This invention relates to an advanced method for biodegradable packaging material (maximum diameter depends on the requirement of the film) since the packaging material for food product is one of the most important operations for post-harvest management. Total production of natural gum produce in India is Around 5,000 tons of plant based gums produced in India annually (except guar gum – a seed based gum and annual production approximately 2,10,000 tons). Globally 40-50% of total production gets wasted due to poor post-harvest management. Fruits and vegetables are important sources of energy in Indian and global use. By-product of fresh horticultural produces is used for extraction of oil, starch and other important consumable products. Some horticultural produces are widely known due to their medicinal values like anti cancerous properties. In present times, there is very high demand of horticultural produces for different purpose.
Total production of fruits and vegetables was around 86 million metric tons and 169 million metric tons respectively in India. Most of the food materials are packed in non-biodegradable synthetic plastic materials which on heating can disperse in food and can be cancer causing. Shelf life extension of horticultural produce is vitally important to increase its availability for consumption purpose. Good packaging is used for the purpose to increasing the shelf life of horticultural produce. Packaging material are made up of polysaccharide-based materials (powders and liquids) and glycerol to increase the plasticizing property of solution. Packaging film can reduce the water vapor transmission rate and retard the respiration process of horticultural produce after packaging.
The primary object of the present invention is formulation of biodegradable natural gum based food packaging material.
Another object of the present invention is to synthesis Eco friendly films.
These and other objects and advantages of the present invention will become readily apparent from the following detailed description.
Summary of Invention
This summary is not a comprehensive overview of the disclosure and does not reflect the main/essential features of the establishment or specify the scope of the establishment. Its sole purpose is to present some of the concepts presented here in a simpler way as a precursor to more detailed explanations presented later.
The primary object of the present invention is formulation of biodegradable natural gum based food packaging material.
In some embodiments of the present invention, the process of this invention comprises of natural gum, initiator, acrylamide(monomer), cross linker, plasticizer, distilled water, curing temperature, drying temperature, casting area, etc.
In some embodiments of the present invention, Potassium persulfate is used as free-radical initiator for polymerization. The initiator basically creates the voids or the free radicals for the polymerization reaction to start which also helps in the bonding pattern of the polymer depending on the amount of cross linker used in further reaction.
In some embodiments of the present invention, N’N-Methyl Bis Acrylamide have the tendency to fit itself in the free radicals and make the best polymerization process resembling the above.
In some embodiments of the present invention, the range of glycerol concentration used as plasticizer was selected on the basis of results obtained from preliminary trials. It was found that the glycerol gave better results with levels 2, 4 and 6 ml/100ml GS, for development of natural gum based hydrogel film. The glycerol with varied concentration was used for developing the film which helped in reduction of brittleness and improved the flexibility and extensibility by acting as spacers between polymer chains and decreasing the intermolecular forces between the adjacent polymeric chains.
In some embodiments of the present invention, the concentration of guar gum (GG) (1 mg/100ml DW) was decided to keep constant throughout the study. Matrix material of GG was decided on the basis of preliminary trials. The concentration of acrylamide solution was decided on the basis of preliminary trials as well as past research work of the researchers. Monomer from acrylic acid (3 ml), acrylamide (3 mg) and sodium hydroxide (4 mg) in 10 ml of distilled water have good antibacterial and antifungal properties as well as it is most important industrial chemical used in the production of plastic soft drink bottles and photographic film which helps to increase the mechanical strength.
These and other aspects of the embodiments herein will be better appreciated and understood when considered in concurrence with the following explanation and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
Brief summary of the figures
Figure 1: Flow chart: Preparation of packaging film for food products.
Detailed Description
These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
In some embodiments of the present invention, the process of this invention comprises of natural gum, initiator, acrylamide(monomer), cross linker, plasticizer, distilled water, curing temperature, drying temperature, casting area, etc.
In some embodiments of the present invention, potassium persulfate is used as free-radical initiator for polymerization. The initiator basically creates the voids or the free radicals for the polymerization reaction to start which also helps in the bonding pattern of the polymer depending on the amount of cross linker used in further reaction. By consideration all above point as well as on the basis of preliminary trials, the values of initiator were selected and ranged from 0.05 to 0.15 mg/100ml GS.
In some embodiments of the present invention, N’N-Methyl Bis Acrylamide have the tendency to fit itself in the free radicals and make the best polymerization process resembling the above. So, after the results of preliminary trials that were showing the effect on the strength of the film while decreasing the amount of cross linker from 0.10 to 0.02mg/100ml GS.
In some embodiments of the present invention, it was found that the glycerol gave better results with levels 2, 4 and 6 ml/100ml GS, for development of natural gum based hydrogel film. The glycerol with varied concentration was used for developing the film which helped in reduction of brittleness and improved the flexibility and extensibility by acting as spacers between polymer chains and decreasing the intermolecular forces between the adjacent polymeric chains.
In some embodiments of the present invention, the concentration of guar gum (GG) (1 mg/100ml DW) was decided to keep constant throughout the study. Matrix material of GG was decided on the basis of preliminary trials. If the concentration of GG was exceeded, it might affect directly as well as indirectly the texture properties of the film which also might affect food packed in it. To overcome these circumstances, the addition of appropriate amount of guar gum plays very important role in film forming solution.
A biodegradable natural gum based food packaging material consists of:
Potassium persulfate as initiator, acrylamide as monomer, N’N-Methyl Bis Acrylamide as crosslinker, guar gum and glycerol as plasticizer.
A method of formulation of biodegradable natural gum based food packaging material comprising the steps of:
mixing KPS initiator (0.05 to 0.15 mg/100ml) with 1mg guar gum;
preparing acrylamide solution using 3mg acrylamide, 3ml acrylic acid and 4mg/10ml NaOH;
mixing both the solution above prepared with stirring at 100 rpm for 30 min;
mixing (0.10 to 0.02mg/100ml) N’N-Methyl Bis Acrylamide crosslinker in the solution and leave for stirring for 2 hours;
adding glycerol in the solution and left for 30 min with stirring;
casting this liquid in plates and placed it in oven at 60oC for 2 hours; and
drying the film in oven at 40oC for 24 hours.
The method as claimed in claim 2, wherein It was found that the glycerol gave better results with levels 2, 4 and 6 ml/100ml.
EXAMPLE 1
EXPERIMENTAL SECTION
The preparation method of packaging has low initial cost as well as operational cost. The preparation method of packaging film is presently not available for small and medium use in India due to non-awareness. Spraying coating method has less uniformity of coating over fruit surface the developed hydrogel film can be used on large scale in food industry for enhancement of shelf life of food product. The swelling index of the developed hydrogel film was such that only the dried food materials can be used for food packaging. So, there should be more improvement of decreasing swelling index instantly so that some products having low amount of water can also be packed using hydrogel film. The hardness of the developed hydrogel film was less as compared to commercially available polythene film. So, there should be more improvement of hardness by addition of such compound which helps for increasing this property of the film. Guar gum was used for development of hydrogel film as key material. Further research work could be done where guar gum in addition with other naturally occurring gum can be used for development of hydrogel film which helps for increasing properties of film such as hardness, swelling properties, tensile strength, transparency etc. Using this we can replace the synthetic non-biodegradable plastics by natural and biodegradable film which can easily be decomposed and is eco-friendly.
The process of this invention comprises of natural gum, initiator, acrylamide(monomer), cross linker, plasticizer, distilled water, curing temperature, drying temperature, casting area, etc. These different components of process are discussed below.
Initiator
Potassium persulfate is used as free-radical initiator for polymerization. The initiator basically creates the voids or the free radicals for the polymerization reaction to start which also helps in the bonding pattern of the polymer depending on the amount of cross linker used in further reaction. By consideration all above point as well as on the basis of preliminary trials, the values of initiator were selected and ranged from 0.05 to 0.15 mg/100ml GS.
Cross linker
N’N-Methyl Bis Acrylamide have the tendency to fit itself in the free radicals and make the best polymerization process resembling the above. So, after the results of preliminary trials that were showing the effect on the strength of the film while decreasing the amount of cross linker from 0.10 to 0.02mg/100ml GS.
Plasticizer concentration
It was found that the glycerol gave better results with levels 2, 4 and 6 ml/100ml GS, for development of natural gum based hydrogel film. The glycerol with varied concentration was used for developing the film which helped in reduction of brittleness and improved the flexibility and extensibility by acting as spacers between polymer chains and decreasing the intermolecular forces between the adjacent polymeric chains.
Natural gum
The concentration of guar gum (GG) (1 mg/100ml DW) was decided to keep constant throughout the study. Matrix material of GG was decided on the basis of preliminary trials. If the concentration of GG was exceeded, it might affect directly as well as indirectly the texture properties of the film which also might affect food packed in it. To overcome these circumstances, the addition of appropriate amount of guar gum plays very important role in film forming solution.
Acrylamide solution
Monomer from acrylic acid (3 ml), acrylamide (3 mg) and sodium hydroxide (4 mg) in 10 ml of distilled water have good antibacterial and antifungal properties as well as it is most important industrial chemical used in the production of plastic soft drink bottles and photographic film which helps to increase the mechanical strength. It also acts as a surfactant and solvent to solubilize the solid particles of starch to render it into a uniform and homogeneous film structure after drying. As aforementioned, the level of monomer for present experiment was selected as 10 ml/100ml DW for the development of hydrogel film.
Curing temperature
The curing temperature was decided as 60°C for 2 hours for the hydrogel film. The curing temperature plays a very important role in development of the hydrogel film, because during preliminary trials, it was observed that exceeding the curing temperature beyond 60°C caused bubbling and foaming in developed hydrogel film and film becoming uneven. Similarly, at lower temperature, film was not dried properly as moisture remained in film affected the physiochemical properties of film directly as well indirectly.
Drying temperature
The drying temperature was decided as 40°C for the hydrogel film. The dying temperature plays a very important role in development of the hydrogel film, because during preliminary trials, it was observed that exceeding the drying temperature beyond 40°C caused cracks in developed hydrogel film and film got ruptured easily. Similarly, at lower temperature, film was not dried properly as moisture remained in film affected the physiochemical properties of film directly as well indirectly.
Casting area
It has found that the casting process was not suitable for film size exceeding 20 cm in diameter. Therefore, for casting the film, borosil petri dish with dimension (20 cm in diameter) was decided based on the preliminary trials and previous research work. This dimension was mainly considered small as for testing of hydrogel film on food product.
For polymerization, we chose an initiator, a cross linker, and a plasticizer. As far as this polymerization was concerned, it was found that the initiator value of less than 0.05 mg/100ml did not produce voids to start the reaction and more than 0.15 mg/100ml created extra voids that resulted in the hydrogel's loosening strength. Crosslinker taking less than 0.02 mg/100ml did not properly trigger cross linking and was unable to shape bond, and no shift in the hydrogel film was observed by using it more than 0.08 mg/100ml as crosslinker is proportional to the initiator. Brittleness in the film was given by the plasticizer taking less than 2 ml/100ml, and more than 6 ml/100ml of it caused an increase in plasticity and the hydrogel formed was more elastic and inappropriate. The final experimental plan was developed by all these trials and values of the initiator, crosslinker and glycerol.
The development of hydrogel film work was accomplished in three phases i.e., first phase consisted of initiation of polymerization, second phase included cross linking and the third phase involved the development of hydrogel film. The detail procedure of the experiments explained in section for preliminary experiments and the process flow chart is explained in Fig 1.
ADVANTAGES OF THE INVENTION:
The invented packaging film aims to get maximum uniformity, biodegradability, transparency, mechanical strength and decreased colour difference on horticultural produce. The film can be recycled or reused after packaging of dry horticultural produce or any other product. The developed packaging film was aimed to increase capacity or strength of film for horticultural produce compare to synthetic plastic films. The invented packaging film has an objective to provide a low cost but the efficient film for low and medium weight produce producers.
, Claims:
1. A biodegradable natural gum based food packaging material consists of:
Potassium persulfate as initiator, acrylamide as monomer, N’N-Methyl Bis Acrylamide as crosslinker, guar gum and glycerol as plasticizer.
2. A method of formulation of biodegradable natural gum based food packaging material comprising the steps of:
a. mixing KPS initiator (0.05 to 0.15 mg/100ml) with 1mg guar gum;
b. preparing acrylamide solution using 3mg acrylamide, 3ml acrylic acid and 4mg/10ml NaOH;
c. mixing both the solution above prepared with stirring at 100 rpm for 30 min;
d. mixing (0.10 to 0.02mg/100ml) N’N-Methyl Bis Acrylamide crosslinker in the solution and leave for stirring for 2 hours;
e. adding glycerol in the solution and left for 30 min with stirring;
f. casting this liquid in plates and placed it in oven at 60oC for 2 hours; and
g. drying the film in oven at 40oC for 24 hours.
3. The method as claimed in claim 2, wherein It was found that the glycerol gave better results with levels 2, 4 and 6 ml/100ml.