BIOFILM BASED ACTIVE PACKAGING BY POLY-LACTIC ACID BIOPOLYMER AND COBALT OXIDE NANOPARTICLES FOR ETHYLENE SCAVENGING ACTIVITY IN FRESH PRODUCE STORAGE

Abstract

This patent illustrates a novel active packaging method developed for ethylene scavenging, which is one of the most important post-harvest factors improving the shelf life of fresh products. This was accomplished using a base of poly-lactic acid bio polymer-matrix with cobalt oxide (CojOu) nano particles. Those nano particles are optimized for adsorbing and degrading a plant hormone called ethylene, which accelerates fruit ripening and spoilage. PLA is a biodegradable substrate, which makes it environmentally friendly and with added cobalt oxide for ethylene-scavenging purposes. Assured to offer a dual benefit i.e. reduction in food decay and elimination of plastic waste, the idea could effectively replace environmental-friendly food packaging systems as well.

Specification

PREAMBLE TO THE DESCRIPTION
Background:
Ethylene is a volatile plant hormone responsible for ripening in fruits and vegetables. Though regulated ethylene exposure is used for agricultural purposes, uncontrolled ethylene buildup during storage accelerates the deterioration process [1], Food waste is an extremely serious issue with huge economic and environmental impacts (Figure-1). The dire need exists for methods that will reduce this ripening process by removing or lowering the levels of ethylene in storage conditions [2],
Problem Statement:
Current active ways of ethylene control include sachets or filters with chemicals, usually in the form of potassium permanganate or zeolite [3], These methods are usually very effective but often not integrated and involve the use of external materials or ecologically unsustainable packaging methods. Besides, most of these systems are based on traditional plastic materials that are non biodegradable and take part in long-term pollution [4].
The new invention to be described herein before eliminates those drawbacks by providing an active packaging made with a biodegradable material which can he directly applied onto fresh fruit. The packaging includes cobalt oxide nano particles as ethylene scavengers to slow down fruit ripening and prolong the shelf life of perishable food even further.
Current Technologies:
Several commercial ethylene scavengers are available:
1. Potassium Permanganate Sachets: These small sachets oxidize ethylene. Their effectiveness decreases with time, and the need for external sachets makes packaging cumbersome [5].
2. Zeolites: Microporous materials such as zeolites when incorporated into plastics are capable of absorbing ethylene under storage conditions. They do not, however, decompose ethylene but must be regenerated with the help of other procedures [6].
3. Activated carbon: Some of the solutions apply activated carbons impregnated with a catalyst. However, these materials commonly used also happen to be non-bio-degradable and need heavy chemical treatment [7],
COMPLETE SPECIFICATION
Summary:
In the present invention, we demonstrate development of a biofilm-based packaging material containing cobalt oxide nano particles incorporated-in poly-lactic acid (PLA) biopolymer matrix. This will
enable continuous scavenging of ethylene during fresh product storage, hence increasing its shelf life and reducing food waste. It proposes a sustainable, and scalable method through the embedding of ethylene control directly into the packing material and avoids additional sachets or filters.
Novelty and Benefits:
1. Biodegradable Biopolymer Base: PLA is a primary bioplastic since it is prepared from renewable biomass resources such as maize starch. PLA is degradable and thus can be presented as a solution to conventional plastics from an environmental perspective. Introduction of nanoparticles in PLA imparts usefulness besides sustainability to the packaging [9],
2. Ethylene Scavenging Nanoparticles: Cobalt oxide nanoparticles (CO3O4) have been reported for excellent ethylene gas absorption along with degradative properties. These particles, owing to their huge surface area and catalytic features, are appropriate candidates for long-term ethylene scavenging [10,11].
3. Performance Enhancement: The use of nanoparticles of cobalt oxide combined with PLA offers a highly active, diffused ethylene scavenging effect within the packaging material itself. This therefore can give more consistent and longer-term control of ethylene as compared to sachet treatments.
4. Eco-Friendly: The packaging, made from PLA is biodegradable hence has least environmental effect. The packing, thus disintegrates by itself when this food is taken in, without the trace [9].
5. Easy to use: You can apply the packaging material directly onto fresh produce with no requirement for filters or sachets. This streamlines the production process as well as the customer encounter.
DESCRIPTION
Materials and Components:
1. Poly-Lactic Acid (PLA): PLA has been chosen as suitable biopolymer because of its advantageous properties like biodegradability, biocompatibility and ability to form support matrix. PLA also features adequate mechanical strength which means it is perfect for food packaging application where fresh product has to be protected.
2. Cobalt Oxide Nanoparticles: It has been selected as the ethylene scavenger for this study because of using nanoparticle active agents, has an advantage of large surface area to volume ratio and also nanoparticies are able to interact with gaseous phase namely adsorptive in order reduce activity of ethylene that leads into increase in" shelf-life period. This property is particularly valuable for use under storage conditions where fresh vegetables are normally packed with cobalt oxide nanoparticle.
Manufacturing Technique:
1. Synthesis of cobalt oxide nanoparticle: The steps will comprise the synthesis of nanoparticies, whereby this process will be accomplished by a sol-gel approach. This marking's gelation and calcination occurs following the sintering step to help in the formation of small-sized, and homogeneous particles with high surface area [12].
2. Polymer-Nanoparticle Incorporation: The cobalt oxide nanoparticies are dispersed in a PLA solution following their synthesis. The overall mixture becomes homogenous in order to have the nanoparticies well distributed within the polymer matrix. Their weight percentage depends on the needed effectiveness of ethylene scavenging, usually from I to 5% wt.
3. Film Casting or Extrusion: The composite of PLA-nanoparticle is further diluted with either solvent casting or through melt extrusion. These films, depending on the type of application, can be coated to form sheets of between 30 and 100 published microns [13] (Figure. 2.).
Working Mechanism:
1. Ethylene Adsorption: Cobalt oxide nanoparticies under study, selectively adsorbs and reacts with the target ethylene gas molecules [10,11].
2. Catalytic Degradation: The cobalt oxide then catalytically oxidized the absorbed ethylene molecules to carbon dioxide and water, so that it reduced contents of packaging with ethylene. This is an ongoing process, which means the ethylene scavenging takes place over a significant portion of these product's life.
3. Biodegradability: The PLA matrix degrades spontaneously after its useful life under composting conditions. When at tiny levels, the nanoparticies of cobalt oxide have no significant environmental hazard [9],
Performance Testing:
1. Ethylene Scavenging Efficiency: The laboratory trials of PLA incorporated with cobalt oxide nanoparticles have been able to show the capacity for reducing ethylene levels by up to 80% in conditions of sealed packaging. This effect can persist for several weeks, depending on its initial ethylene concentration and the amount of nanoparticles used.
2. Shelf-life extension: Fruits packaged with the cobalt oxide-PLA sheets showed a 30-50% longer shelf life compared to conventional packaging. For instance, bananas and tomatoes take their time to ripen and correspondingly experience negligible softening, discolouration, and weight loss.
3. Biodegradability: The films made from the PLA-based completely disappeared in 3-6 months under the controlled industrial composting process with no detrimental effect due to the cobalt oxide nanoparticles.
We Claim
Claim I: Application for a biodegradable active packaging material based on a poly-lactic acid matrix and cobalt oxide nanoparticles for ethylene scavenging to improve the shelf life of ethyleneproducing products.
Claim 2: The active packaging material referred to in Claim 1, where the cobalt oxide nanoparticles are homogenized within the poly-lactic acid matrix.
Claim 3: The active packaging material of claim 1, wherein the size ranges from 10 nm to 50 nm and is utilized in an amount of which reaches by a mass percent outflows ranging from 1% to 5% by weight.
Claim 4 The active packaging material according to claim 1, wherein the matrix is a polylactic acid film with thickness between 30 and 100 micron.
Claim 5: Process for lowering an atmosphere ethylene level in a fresh produce storage warehouse, wherein the product is packed with poly-lactic acid film loaded of cobalt oxide nano-particles.

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