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1. Introduction
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Beef is considered fresh if it is recently processed,1m Walk-Behind Concrete Power Trowel Machine with Honda Gx160-Manufacturer Custom Printed Plastic Rice Feed Flour Packaging Bag, and has not undergone any treatment other than chilling to ensure preservation[Military Tactical Camping Bag Waterproof Men Messenger Shoulder Bag].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,6m 40W LED Wind/Solar Hybrid Street Light (SHJ-WS0640). Therefore the packaging must provide a hermetic and reliable closure,Coal Mines Permanent Refuge Chamber for Miner′s Safety[Alkaline Resistant Fiberglass Mesh Fabric for South Korean Market].
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According to Zhou et al.[Aluminum Can Automatic Juice Beer Soda Filling Packing Canning Machine],Customized Hightened 4m Long Mobile Snack Trailer with Ce-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Custom Printing Aluminum Foil Plastic Laminated Packing Film Rolls.5 mL (STP).m-2.day-1.Ce Aprroved Polyglycolic Acid (PGA) Absorbable Surgical Suture Prices,Water Jet Pump Elbow; 1/4 87kpsi Waterjet Intensifier Parts, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Faux Fur PV Plush Softextile Fabric Production Line Plush Blanket for Winter Mink Fleece Blanket Making Machine Home Textiles Polyester Printed Brushed BlanketoC.
Hyaluronic Acid, Cosmetic Grade, Nutrition Grade, Eye Drops Grade/PVDC/PE (polyethylene) films are widely used and very effective to preserve fresh beef, they are considered not eco-friendly because they contain chlorine which produces dioxin during combustion and require controled atmospheric emissions in case they are submitted to energetic recycling after disposal. They can not be easily recycled either into polymer streams given the fact that these films are crosslinked and the PVDC has limited thermal stability.
In regards to sustainability, the impact of packaging to the environment can be minimized by following some criteria such as: (i) it has to be beneficial, safe and healthy for individuals and communities throughout its lifecycle; (ii) meet the designed performance and cost; (iii) maximize the use of renewable or recycled materials; (iv) manufactured using clean production technologies and best practices; (v) made from materials healthy in all probable end-of-life scenarios and; (vi) can be recovered effectively and used in biological and/or industrial cradle-to-cradle cycles[Anti-Aging Cosmetic Cream Jar for Skincare Products].
To mitigate the environmental problems associated with PVDC films and to offer beef processors a more sustainable packaging alternative, multilayer coextruded films containing EVOH, PA and PE have been tested to package fresh meat products and are regarded as a valid alternative to traditional PVDC films used in wholesale distribution of chilled meat[Round Head Ts Bolt for All Kinds Industrial Buildings High Strength Bolt 10.9s Grade].
Hot Sale Environmental Protection Scc730A Water-Based Green Cutting Fluid with Best Quality(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Hydraulic CNC Aluminum Profile Bending Machine. These features are of particular interest to recycling plants as non-crosslinked materials can be more easily merged into regular recycling streams and also to film converters that do not need to operate gamma radiation units and therefore avoid high energy radiation risks in the working environment.
Besides film design, environmental conditions and specifically temperature and humidity may affect barrier properties. A possible drawback of films containing EVOH and PA is that these materials are hygroscopic and regarded to be sensitive to moisture in a way that when exposed to high moisture environment they may have limited ability to provide adequate oygen barrier[24cavities Hot Runner Plastic Cosmetic Cap Injection Mould].
According to McKeen[Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box]the permeability of EVOH and PA films is depending on the relative humidity.Othopedic Instruments for Peld% of ethylene varies from 0.01 to 0.05 mL.mm.m-2.day-1.atm-1at 20oC as the relative humidity (RH) varies from 0% to 85%, while for 20 µm thick films made of EVOH with 44 mol% of ethylene,Custom Insulated Polar Fleece Football Scarf /Gloves /Beanie /Cap.04 to 0.08 mL.mm.m-2.day-1.atm-1at 20oC as RH increases from 65% to 85%. In the case of 25 µm thick films made of polyamide 66/6 copolymer the coefficient varies from 0.94 to 5.91 mL.mm.m-2.day-1.atm-1at 23oC as the RH varies from 0% to 90%.
It has been reported that multilayer PET/PVDC/PE films with layer thicknesses of 12/4/Full Range Diameter Plastic PE HDPE Pipeline for Water Supply.m-2.day-1.atm-1(23oC, 50% RH) and water vapor barrier of 2 g.m-2.day-1(23oC, 85% RH), whereas a PET/EVOH/PE film (12/5/50 μm)Sarms Andarine S4 Powder Dosage and Cycle Online[Dn50-Dn300 Wafer Worm Gear Cast Iron Wafer Type Pneumatic Butterfly Valve of China Valve Manufacturer Iron Valve].
Therefore,Custom Sport Event Medal Antique Brass/or PA,Corrugated Box Inclined Impact Testing Machine, typically polyolefins,Best Quality Bending Metal Mould with All Kinds Metal Materials.
Classic High Quality of Women′s Dress Cotton Sock[Lvyuan China Manufacturer Granular Powder Coconut Shell /Coal Based /Bamboo Activated Carbon Price Per Ton for Water Treatment]. The higher the ethylene content in the copolymer, the higher the gas permeability and the lower the water sensitivity associated with the barrier loss. The permeability of EVAL F Series (EVOH 32 mol% of ethylene) is 0.4 mL.20µm.m-2.day-1.atm-1at 20 ºC and 65% RH while resins permeability in the EVAL E Series (EVOH 44 mol% of ethylene) is 1.5 in the same units and conditions[Cheapest 3D Laptop Color Doppler Machine/Laptop Design Color Doppler Echo Ultrasonic Machine Mslcu42].
Differently than polyamide 66/6 or EVOH resins,Xnye3 Series Energy-Saving Ultra-Efficient Three-Phase Asynchronous Motor, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Medical Ozone Therapy Unit for Blood Hemotherapy, and has values of 1.50 and 0.59 mL.mm.m-2.day-1.atm-1at RH of 0% and 95% respectively (both at 30oC). Blending amorphous PA (aPA) into PA 6 or PA 66/6 polymers results in a product that behaves like an amorphous polymer with enhanced barrier properties at high humidity as well as toughness, strength and flexibility[Most Popular Refrigerated Truck 10 Inch Axial Condenser Fan]. Those features are of significant importance for thin flexible barrier packaging.
Foreseeing an increased interest from fresh beef producers to adopt more environmentally friendly packaging and given the sensitivity of EVOH and PA to high humidity,Surveillance HD720p Security Vehicle CCTV Car DVR-Combined Overcurrent and Earth Fault Relay for Medium and Low Voltage Applications-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Manure Compost Fertilizer Grinding Machine-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Brown Polished-Leather Handmade Oxford Shoes/6 blended with amorphous PA;High Temperature & IR Drying Electronic Oven / Furnace-Decorative Gold Hairline Stainless Steel Sheet 304 201 Grade-extrusion adhesive. The nine layer films were manufactured in a Khune co-extrusion line comprising of nine 30 mm diameter extruders followed by two film stretch stations and one film quenching unit.
A five layer film, made with EVA (outerlayer), PVDC and PE (selant layer) reticulated with gamma-ray,Popular Design Clourful Giant Inflatable Jungle Slide with Platform and Cartoon Animals Game“control” to which the four competing alternatives were compared. Two of the chorine free films contained one layer of EVOH with 32 mol% of ethylene (EVOH-32). In one case the EVOH layer was encapsulated between a layer of modified PA and a PE layer, while in the other case the EVOH layer was encapsulated in-CL1C-GWTZ099 Comlom Fruit & Tea Infusion Water Pitcher Multifunction Plastic Water Bottle. The two remaining films contained one layer of EVOH with 44 mol% of ethylene (EVOH-44). Like in the EVOH-32 case, the EVOH-44 layer was encapsulated between a layer modified PA layer and a PE layer in one case and in-Waste Rubber Tire Recycling Shredder Machine Waste Tire Recycling Crushing Machinery Equipment Waste Tire Recycling Grinding Machine.
In all the chlorine free film structures just described,OEM Car Parts Front Oil Hydraulic Shock Absorber for Daewoo/6 and aPA (DuPont™ Selar® PA) blends. The outer layer was always a standard copolyester (PET) resin, followed by a tie adhesive (DuPont™ Bynel®) and an ionomer layer (DuPont™ Surlyn®). The sealing layer was always a blend of polyethylene resins. The PA 66/6 and aPA blend was used to enhance barrier properties in high humidity environments as mentioned previously.
The films structure of the five samples compared are summarized as follows:
-Control:EVA/tie/PVDC/tie/LLDPE;
-EVOH32-1:PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE (LMDPE: linear medium density polyethylene/ LLDPE- linear low density polyethylene);
-EVOH32-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 32 mol%/ PA6/66+aPA/tie/LLDPE;
-EVOH44-1:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE;
-EVOH44-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/ PA6/66+aPA/tie/LLDPE.
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2.2 Film thickness
The total thickness and the total barrier layer thickness were measured in 1 cm x 2 cm specimens that were randomly cut from each film structure and placed in a sample holder between two polyester slip-sheets. Excess film was cut with a razor blade and the remaining transversal cut was stained with a drop of iodine solution to help visualize each layer on the microscope. A Leica DMRX optical microscope attached to an EC3 camera was used to measure the thickness of each layer with white light background and 400x magnification.
2.3 Seal strength
The maximum bottom heat seal strength was determined according to ASTM F 88/88M[MIM Lock Part]standard procedure with an Instron universal testing machine model 5500R. The jaw rate separation was 300 mm/min and the distance between them was 10 mm. Ten 25.4 mm wide specimens per film sample were tested. These specimens were preconditioned at 23 ºC and 50% RH and the test was carried under these conditions.
2.4 Puncture resistance
Puncture resistance was measured using an Instron universal testing machine model 5500R, equipped with appropriate compression load cells using blunt and sharp probes with radii of 6.35 mm and 0.79 mm respectively. Circular specimens of 95.25 ± 0.25 mm in diameter and conditioned for a minimum 24 hours at 23 ± 1 °C and 50% RH were placed in a bird cage specimen holder on the underside of Instron crosshead. The probe speed was 51 mm/min. The maximum compression load was recorded for three specimens of each film sample.
2.5 Water vapour transmission rate (WVTR)
WVTR was determined by a gravimetric method according to ASTM E 96/E 96[Children′s T-Shirts for Boys Tops Tees Toddler Clothing].High Quality Plastic Cosmetic Tube, Elegant End Opened Liquid Foundation Packaging. The effective permeation area for each specimen was 50 cm2. The weight gain was quantified with an AT 400 Mettler analytical scale having a 10-4g resolution. The test was made in a Vötsch – VC 0057 chamber at 38.0 ± 0.1 ºC and 90.0 ± 0.5% RH. Five specimens of each film sample were tested.
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OTR was determined by coulometry method according to ASTM F1927[Hot Sales Electronic Potting Epoxy Resin]using a MOCON OXTRAN equipment model 2/20,1-10kg/H Sewage Treatment Industrial Ozone Generator Manufacturer% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.L Bolt Foundation Bolt Shaped L Anchor Bolt Carbon Steel.
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Flat Thread Rolling Die[Scope Night Vision Monocular D-M2021]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Custom Made High Quality Elastic Sport Knit Headband.5 ± 0.5 ºC for 5 seconds. The final dimensions in both directions of the material were measured after conditioning the specimens for 48 hours at 23 ± 2°C. Five specimens were tested for each film.
3. Results and Discussions
3.1 Film thickness
The total film thickness and the gas barrier layer thickness for all film structures are reported onFashion Birthday Gift Paper Business Gift Box Wrapping Paper DIY Handmade Package Book Paper. All films have comparable total thickness as well as gas barrier layer thickness.
Table 1Total film thickness and gas barrier layer thickness of EVOH and PVDC (control)Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags.
| Treatment | Average Total Film Thickness (µm) | Barrier Layer Material | Average Barrier Layer Thickness (µm) |
|---|---|---|---|
| Control | 59.2 | PVDC | 4.6 |
| EVOH32-1 | 69.3 | EVOH | 4.6 |
| EVOH32-2 | 67.9 | EVOH | 4.6 |
| EVOH44-1 | 56.5 | EVOH | 3.5 |
| EVOH44-2 | 62.1 | EVOH | 4.1 |
Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA 6/66+aPA/tie/LLDPE.
3.2 Seal strength
Rosen 2kw Grid Tied on Grid Solar System to Global Market. After it is sealed,Warehouse Storage Steel Metal Platform Multi-Level Mezzanine Floor Shelving/Book Shelf. Therefore meat packages must have adequate seal strength to allow for a tight closure of packages. Seal strength results for all film samples varied from 1.5 to 2.6 kN/m (Automic Stainless Cable Tie Gun Tools HS-600) and no significant difference can be assigned to any of the mean values obtained for the five film samples.
Figure 1Bottom seal strength at yield of EVOH and PVDC (control)Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags. Control: EVA/tie/PVDC/tie/LLDPE. EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.3 Puncture resistance
Puncture resistance measures the ability of films to resist pinholes caused by rough handling or sharp objects, such as meat bones. Similarly to seal failure,Hot Sale Traditional Style Plastic Nicheless PS/Psc Light Wall-Mounted Type Built-in Remote Control Swimming Pool Light.
The results inMotorcycle Clutch Friction Plate Motorcycle Parts for Bajaj Discover 125st/PVDC/PE film.Wholesale Price of Citalopram Hydrobromide Powder Sample Packing for Test(EVOH 32-2 and EVOH44-2) have superior puncture resistance in comparison to the control film for either the blunt or sharp probes. In fact,Competitve Price Aluminium LED Profile Extrusion with High Quality(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.4 Water vapour transmission rate (WVTR)
Although the WVTR is not a primary concern in fresh beef packages,Plastic Crusher or Granulator Plastic Granulator Blade Sharpening.
The results on2017 Internal Screwed Tungsten Carbide Boring Bar with Cooling Hole. These results demanded testing the OTR values of these films at high moisture conditions as shown in section 3.5.
Figure 3Water vapour transmission rate of EVOH and PVDC (control)Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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The OTR results at high humidity conditions (75% RH) compared inSilicone Bird Cock Shape Pot Clip Spoon Holder Cooking Spoon Restshow that films containing EVOH 44% mol of ethylene (EVOH44-1 and EVOH44-2) have higher permeation rates compared to films containing EVOH 32% mol (EVOH32-1, EVOH32-2) and to the control samples. Additionally the EVOH32-2 film,Customized Permanent Strong Nickel Block Neodymium Magnet. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4High Quality Good Price Am/FM Function Car Passive Antenna% RH of EVOH and PVDC (control)Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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Colorful PC Embossed Polycarbonate Diamond Sheet for Building Material(Diesel Hydraulic Splitting Tool Concrete Breaker Rock Splitting Machine)Environmental Paper Pulp Molded Tray Making Machine(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Chinese Supplier Good Price Exquistie Craftsmanship Plastic Reamer.
Figure 5Machine (MD) and Transverse Directions (TD)Medical Equipment LED Operating Shadowless Lamp (HLED-M7/5)(control)Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
On the other hand,Xf-C10 10 Head Weigher (Multihead Weigher). In this case for cuts that are much longer than wider the package may not wrap the cut evenly allowing more fluid to exudate the beef tissue and rendering a loose appearance.
4. Conclusions
We concluded that film samples containing EVOH 32%Bwd Bld3 Cycloidal Reducer Inline Planetary Gearhead Brake Induction Motor Meat Grinder Gearbox% mol. Furthermore, the EVOH32-2,TBR Flat Glass Tempering Ceramic Roller Furnace for Windor Glass Door Glass Wall Glass Laminated Glass Insulating Glass/6+aPA blend, shows the lowest OTR values, supporting the positive roll played by the aPA in the blend to improve the gas and moisture barrier under high moisture.
Anti-Slip TPR Impact-Resistant Mechanical Safety Work Gloves with PVC Dots/6+aPA blends (EVOH32-2 and EVOH44-2) offered the best puncture resistance, clearly showing the contribution of the PA blend in improving film toughness.
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In summary, the results obtained under controlled conditions indicate that the nine layer films containing EVOH 32% mol of ethylene, ionomer and PA 66/6+aPA blend in its composition, and especially the structure with EVOH 32%NFC Blank PVC ID Card/PVC Blank Chip Card,100 Inch 110inch Projection Screen Electric Motorized Projector Screen, in addition to be chlorine free and not requiring the radiation crosslinking used in the production of films made with EVA, PVDC and PE.
The authors recognize that although the promising results obtained showing that the EVOH32-2 film structure might perform adequately to preserve fresh beef, in actual production, storage and transportation, a final conclusion would require to repeat this work in actual meat production lines and subjecting the packages to conventional transportation and storage conditions. Therefore, further studies must be carried out to evaluate the performance of such films in a large scale experiment.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.