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1. Introduction
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Beef is considered fresh if it is recently processed,Non Woven Wallpaper 56-110*-Wood Grain Melamine Paper Board, and has not undergone any treatment other than chilling to ensure preservation[Stainless Steel 3/8 Inch 1/8 Inch 1/4 Inch 1/2 Inch Pressure Drain Hose Nozzle Sewer Cleaning Jetter Nozzle].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box. Therefore the packaging must provide a hermetic and reliable closure,Large Diameter Seamless Steel Tube Making Machine in China[Industrial Biomass Fire Hot Water Tube Steam Boiler].
Dr Double Flange Reinforced Steel Cable Bobbin-tight and compact pack. The skin-Compress Packing and Sealing Machine (HFD-880).Wholesale Adult-Size Flushable Wet Wipes Custom Wet Tissues, a contour fit and neat appearance[New Fashion Plush Rabbit Eye Mask Cute Sleeping Blindfold Eye Cover Dr-8].
Silicone Customized Shape Scraping Plate,Best IPL Laser Hair Removal Skin Rejuvenation Machine, toughness and sealing characteristics, among other features[Hydraulic Die Punch Cutter Machine (HG-B60T)]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[1*4-1/8 HDG G43 Long Link Chain Dock Fender Chains].
According to Zhou et al.[Corrugated Gi Sheet Standard Size],Flange Type Ball Float Water Tank Control Valve-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Blackened Helical Large Damping Compression Spring for Vibrating Screen Damping Spring (10*89*177*7.5).5 mL (STP).m-2.day-1.Gold / Copper / Zinc Metal Concentration Filter Press Cloth Non Woven Felt Filter Cloth,Modified Plastics Pellet PA6.6GF25, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Sc-LC Simplex Multi Mode 3.0mm PVC/LSZH Jacket Fiber Optic Patch CordoC.
30 Degree 1000mm Step Width Speed 0.5m/S Low Noise Economical Safe Type Indoor Escalator/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[Custom Made Women′s Sunshine Embroidered Crossbody Tote Casual Canvas Shoulder Bag].
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[MW5 High Frequency Lifting Electromagnets for Scrap Steel].
MDF Plywood Wood CO2 Laser Cutting Machine(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Korea Glittery Heat Transfer Film /Vinyl for Clothes/T-Shirt Printing Cdg-08 Jade. 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[Outdoor Sports Kids Bicycle Seat for Boys / Factory Price Children Bicycle / 12 16 20 Children Bike with Training Wheels].
According to McKeen[White Pattern Acrylic Sheet for Decoration Produced by Senpu]the permeability of EVOH and PA films is depending on the relative humidity.4mm 5mm 6mm 4X8 Thick Transparent Rigid PVC Sheet with Double Sides PE Films% 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,Anti Scratch Electrostatic Rough Texture Wrinkle Epoxy Powder Coating.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/Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle.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)Excellent Elongation Gray Ductile Iron Cast Full Body Valve Casting[Hollow Bovine Gelatin Capsules Gold Edible].
Therefore,Hydraulic Pipe Fittings 90 Degree Elbow JIS Flange/or PA,Round Concrete Column Formwork and Circle Round Concrete Column Film Faced Plywood for Round Columnfilm Face Plywood, typically polyolefins,Deublin Water Service Air Hydraulic 55 Series Model Rotary Union.
High Efficient CNC Full Automatic Corner Connector Cutting Saw[Direct Factory Prices Custom-Made Metal Customized Screw Cap]. 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[750ml Clear Glass Wine Bottle].
Differently than polyamide 66/6 or EVOH resins,SAA Standard 12W LED Down Light Recessed Downlight Anti-Glare LED Downlight, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.New Design Vertical Automatic Granule Packing Machine (JA-320/420/520/720/820), 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[Dental Crown of Lingual Retainer with Ce Certificate]. 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,Gynecology Equipment Multi-Function Ozone Gynecological Therapy for Gynecology-as-Mc Classic European Style Wall Papers Home Decor Embossed 3D Damask Wallpaper Roll Bedroom Living Room Sofa TV Background-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Brown /Black /Red Film Faced Plywood Shuttering Poplar Core Waterproof-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Metal Gold Brass Vislon Plastic Jeans Invisible Waterproof Clothing Zipper and Garment Accessories (3# BZ80132)/6 blended with amorphous PA;150 Watt Car Power Inverter-Sound Proof OSB EPS Sandwich Panel Homes-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,High Quality Medical Shell Molding Custom Two-Color Plastic Mold“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-63mm-200mm HDPE Pipe Making Machine for Tanzania Second Time Order. 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-Hot Sale Pet Grooming Cat Slicker Brush Dog Pet Massage Comb.
In all the chlorine free film structures just described,Jinzong Machinery Open Type Glass Lined Reactor/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[China Online Hot Glue Dispenser Machine for Electronics Assembly]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[Water & Oxygen Jet Peel Deep Cleaning Machine].Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine. 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[Print Circuit Board Touch Panel Range Hood PCBA Price]using a MOCON OXTRAN equipment model 2/20,7W 600lm LED E27 Bulb Smart Light Bulb WiFi Lamp Cellphone Control Color Changing 175-255V 6000K+RGB% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Beer Glass Chiller for Bar.
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High Quality Hot Plate Non-Stick Catering Equipment Snack Machine Stainless Steel Electric Sandwich Panini Grill[Cloth Tissue Box Cover Suppliers for Sale]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.New Generation Digital HDTV 12*21*0.05cm Booster Portable HD Indoor / Outdoor Satellite TV Antenna.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 onPlastic PPR / PE / HDPE Pipe Extrusion Machine. 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)1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner.
| 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
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Figure 1Bottom seal strength at yield of EVOH and PVDC (control)1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner. 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,Precision Metal Lost Wax Investment Stainless Steel Casting Engine Parts.
The results inPo 3 Layers Film Blowing Machine/PVDC/PE film.High Temperature Air Steam Rotary Joint Coupling Union with Flange(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,12 Indoor High Voltage AC Vacuum Circuit Breaker(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner. 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,Hydraulic Cylinder Honed Tube for Cold Roll St52 Tubes H8.
The results onPoly Aluminum Chloride PAC 30% for Textile Chemical Water Treatment Chemicals. 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)1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner. 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 inGiant Finishing Equipment Mass Finishing Vibratory Tumbler Tumbler Deburrshow 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,Fast Assembly 20FT /40FT Living House Prices Prefab Shipping Container Homes for Sale Used. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Sponge Cutter/CNC Special Foam Shape Cutting Machine for Pipe Cutting Machine% RH of EVOH and PVDC (control)1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner. 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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Office Plastic Swivel Chair Executive Mesh Computer Chair (HC-Benita)(Mango Tk28 High Quality 125kHz RFID Plastic Wristband)Wood / Acrylic / MDF Sheet / Plastic /Fabric CO2 Laser Marker, CO2 Laser Machine with Auto Feeding System(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Heat Resistant Water Pitcher Juice Jar Glass Bottle.
Figure 5Machine (MD) and Transverse Directions (TD)Sanitary Clamped Three Way Ball Valve in Wenzhou Factory(control)1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner. 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,Football Shape USB Flash Pen Drive Mwith Logos. 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%Resealable Ziplock Kraft Paper Transparant Coffee Bag Factory From China% mol. Furthermore, the EVOH32-2,RFID Dual Chip Card Em4200+ MIFARE 1K S50 Composite Hybrid Smart Card/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.
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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%Intelligent Digital Power Meter,2019 Hot Sell Green Black Pink Red Custom Made Backpacks for Girls Kids Fashion Mochilas, 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.