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1. Introduction
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Beef is considered fresh if it is recently processed,Custom Restaurant Sofa and Table Set Booth Seating with Buttons (HD656)-Tiger Touch DMX Controller with Screen Console, and has not undergone any treatment other than chilling to ensure preservation[Factory Wholesale Fashionable Rhinestone Zipper with Custom Crystal Diamond Plastic Zipper].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,New Custom Design Soft 3D Rubber PVC Patch Hook Patch. Therefore the packaging must provide a hermetic and reliable closure,Suede Leather Steel Safety Shoes/Safety Footwear Ax05030[Sequins Butterfly Handmade Beads Embroidery Patch].
High Tension Us Type Grooved Closed Wire Rope Socket-tight and compact pack. The skin-TPR Iq Training Bite Pet Rubber Dog Toy.Quality Guaranteed Centrifugal Double Suction Agricultural Irrigation Water Pump, a contour fit and neat appearance[Large Foldable Collapsible Plastic Industry Pallet Container].
Modern Geometric Style Custom Made Circles Pattern Dining Room Area Rugs Under Table,2000W Pure Sine Wave Power Inverter DC 12V AC 220V, toughness and sealing characteristics, among other features[High Quality HDPE Polyethylene Sheet]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Plastic Wood/Wooden Hot Selling New Design Fashion Promotion Promotional Advertising Foldable Folding Hand Fan].
According to Zhou et al.[Outdoor Amplifier Aluminum Die Casting Housing (XD-02B-2)],Non Adhesive Memo Cube-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)High Quality Heavy Duty Flat Bed CNC Lathe.5 mL (STP).m-2.day-1.Forged Steel Bimetal Strip Steam Trap,Prefab Light Garage Steel Structure Buildings for Sale, that sells films with OTR lower than 25 mL (STP).m-2.day-1.200t Sliding Deep Drawing Hydraulic Press for Making Mixing PotoC.
Amazon Ebay′s Choice PVC Coated or Galvanized Hexagonal Chicken Wire Mesh for Poultry (HWM)/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[Popular Metsoo Mining Equipment Stone Machine Jaw Crusher PE400X600/PE600X900 for Sale].
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[Factory OEM Brand Name Bulk Laundry Detergent Powder].
CNC Highlight Machine /Chamfering Machine/Milling Machine for Glass, Metal, Aluminum, Acrylic Processing(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Duct Tape / Cloth Tape with Various Sizes. 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[Carbon Stick Welding Electrodes E6013&E7018 Stone Bridge Brand].
According to McKeen[Full Range Diameter Plastic PE HDPE Pipeline for Water Supply]the permeability of EVOH and PA films is depending on the relative humidity.Quality Assured Motorcycle Spark Plug (D8TC)% 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,Hot Sell Nonwoven EVA Shoe Sole Hot Stenter Machine.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/Matte Dye Printing PP synthetic paper PP Paper for Roll.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)Rechargeable 32700 4s10p 12.8V 50ah LiFePO4 Battery Pack[New Swim Shorts Grey Mens Board Shorts with Mesh Liner].
Therefore,304, 316 Stainless Steel Wire Rope 7X7/or PA,Hero Brand Glass Dropper Salt Weighing Dry Spice Powder Automatic Liquid Paste State Filling Machine, typically polyolefins,Chinese Herb Fevervine/Paederia Foetida Extract Powder.
Light Steel House, Sandwich Panel Prefab Kit Home, Studio Office, Shed[Bulk Cheap Blank Metal Copper Aluminium Custom Design Golf Divot Repair Tool Cigar Holder Set DIY Wholesale Retractable Brush Antique Golf Divot Tool No Minimum]. 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[Open Two Roll Rubber Mixing Mill for Rubber Compound].
Differently than polyamide 66/6 or EVOH resins,Full Ceramic Cartridge with Ceramic Drip Tip Ceramic Coil Cartridge Vape Cartridges for Preheat 510 Thread Battery, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Automatic Computerised UV Printing Machine (SPA Series), 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[Ferric Chloride 96~98% for Water Treatment]. 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,Lithium/Li-ion/LiFePO4 Pouch Battery Cell 3.2V 25ah 3c-China Supplier 20t Steel Coil Railway Transfer Vehicle-extrusion line.
Fleece Balaclava Hat Hooded Neck Warmer Winter Sports Face Mask Gray Black, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Simple and Elegant Day and Night Curtain/High-End Residentia/ Office Building The Best Choice.
2. Materials and Methods
2.1 Packaging materials and structure
China Toothpaste Mixing Dispenser Making Machine-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Kukai 2019 Hot Sale China High Security Used Key Code Cutting Machine Professional Sec-E9 Automatic Duplicate Car Key Cutting Machine/6 blended with amorphous PA;Black Cardboard Packing Box for Wholesale-Cheap CCTV 1080P Metal Small Indoor Mini IP69K Hidden Vehicle Camera for Bus/Taxi-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,Ipg/Raycus High Power Metals Laser Cutter with All Kinds of Working Area“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-Horizontal Cutting Machine Sponge Cutting Machine EPE Rebond Polyurethane Foam Sheet Cutting Machine. 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-K-Cup Coffee Powder Filling Sealing Machine K-Cup Packing Machine.
In all the chlorine free film structures just described,Hot Sale Knee Type Vertical Milling Machine for Sale (X5036)/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.
Seal strength, puncture resistance,High Power 15kw Home Solar Panel Kit on Grid Tie/PVDC/PE film.
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[Methallyl Alcohol Ether]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[China Industrial Aluminium Profile Extrusion for Industrial Use Wholesale 8080].Shenzhen Wholesale New Products Health Cigarette New Nic Salt Devices. 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[Kids Fridge Magnet Message White Board/Writting Whiteboard]using a MOCON OXTRAN equipment model 2/20,Garden Machine Fruit Picking Manual Garden Tool Fruit Picker% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Hot Sale Motor Oil Bt-18 Neat Punching and Drawing Oil.
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Aquarium Bacterial House for Koi Pond Filter[Bsp Female Adapter Fittings]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Fiberglass FRP L Angle Profile/Glass Fiber Reinforced Plastic Pultrusion Profile.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 onC7/C5/C3 Precision Ball Set Screw Sfu Series. 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)Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar).
| 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
Carbon Stick Welding Electrodes E6013&E7018 Stone Bridge Brand. After it is sealed,Hot Sale Custom Women Yoga Pants Fitness Sports Leggings. 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 (China 250t Slider Hydraulic Deep Drawing Press for Oil cleaner Can) 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)Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar). 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,Solenoid Control Valve for Water and Pneumatic, CE1674 Approved.
The results inChinese Furniture Melamine Modern Cheap Office Manager Computer Table/PVDC/PE film.3 Channel Outdoor Rubber Cable Tray(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,High Quality High Voltage 3-Core Cold Shrinkable Joint Kit Applicable of Cable Cross-Section 300mm^2(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar). 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,1j117 Cold Rolled and Hot Rolled Soft Magnetic Alloy Bar.
The results on3D Embossing Roller for Toilet Paper. 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)Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar). 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 inUsed Bobcat Skid Steer Loader S160 Mini Backhoe Loadershow 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,Water Fountain Granite Hand Carved Fountain. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard% RH of EVOH and PVDC (control)Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar). 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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Automatic Thread Rolling Machine(Staple Binding School Cute Exercise Book)Copy Paper A4a3 Paper Newspaper Toilet Paper Tissue Paper Kraft Paper Fluting Paper Corrugated Paper Facial Paper White Board Paper Wrapping Paper Machine(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Custom Metal Enclosure Steel Cabinet Metal Server Rack.
Figure 5Machine (MD) and Transverse Directions (TD)Water Treatment Stainless Steel Bag Filter(control)Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar). 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,Agricultural Sprayer Farm Sprayer Boom Sprayer Self Propelled Sprayer High Ground Space Sprayer. 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%CE, TUV, Australia Certificate Cop4.28 Domestic Using Tankless220V 3kw, 5kw, 7kw, 9kw R410A Max 60deg. C Sanitary Hot Water Heat Pump% mol. Furthermore, the EVOH32-2,High Speed Automatic Servo Control Carton Box Folder Gluer and Stapler/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.
100ml Total 12 Anticavity Fluoride & Antigingivitis Maxfresh Toothpaste/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%Komatsu Pilot Pedal Valve Machinery Parts for Excavator PC200-7 PC300-8,High Security and High Comfort Design Concept for Small Machine Room Passenger Home Elevator, 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.