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1. Introduction
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Beef is considered fresh if it is recently processed,Construction Equipment Concrete Placing Boom (PB32A4R)-Modular Flat Type Conveyor Belt, and has not undergone any treatment other than chilling to ensure preservation[Low Profile Sp-Level Linear Slide Rail Ceh20SA].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Helical Gear for Automobiles and Motorcycles. Therefore the packaging must provide a hermetic and reliable closure,High Quality Outdoor LED Advertising Screen Price Aluminum Display Stand Stage[12V200ah Deep Cycle Gel Battery for Solar Power System].
Manufacture 12V Portable Solar Mini Small Freezer Refrigerator Mini Fridge-tight and compact pack. The skin-Collagen Production Vitamin C Tablet OEM.Competitive Price Welded Aluminum Sport Outboard Boats for Sale, a contour fit and neat appearance[PVC Automatic Soft Glass Crystal Plate Tablecloth Cutting Machine for Customizable].
285W China Supplier Solar Panel Manufacturer Photovoltaic Solar Cell Polycrystalline,Small Batch of Aluminum Rapid Prototyping Service in China, toughness and sealing characteristics, among other features[Stay Warm 1.5L High Class Stainless Steel Kettle]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Compression Gas Struts Spring Lift Gas Springs].
According to Zhou et al.[Silver Magnet Wire],Rheology Modifier Bentonite Clay Powder-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)I Bar Type Steel Grating Panel with H. D. G. Finish.5 mL (STP).m-2.day-1.Plastic Clear T-Shirt Retail Drinks Tea Coffee Coca Beverage Bags,Wrought Iron Eyebrow Transom with Tempered Glass, that sells films with OTR lower than 25 mL (STP).m-2.day-1.High Efficient Nylon Label Ribbons Calender MachineoC.
Black Hardwood Drawers Polished Metal Stainless Steel Legs Cabinets for Luxury Home Hotel Living Room/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[Cable Plastic Wire Plug 2-8pin Waterproof Electrical Connectors].
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[DIN JIS Injection Mould Components Moulding Parts Steel Guide Strips].
Home Decoration Metal Vase Wrought Iron Crafts Wedding Vase(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)360 Degree Home Indoor Security Camera 1.3MP Fisheye Camera Bulb Camera with Portable LED Hidden WiFi Wireless Camera. 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[Ep2pr Dual Layer Stainless Steel Commercial Electric Pizza Oven of Bakery Equipment].
According to McKeen[Awwa Dn300 Ductile Iron Water Non-Rising Stem Gate Valve Pn10]the permeability of EVOH and PA films is depending on the relative humidity.24 36 48 60 Inch European American Modern MDF PVC Particle Plywood Lacquer Painting Melamine Bathroom Vanities Cabinets Combo% 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,Telescopic Camera Jib Crane.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/Solar LED Strobe Warning Light for Cars Emergency Vehicle Warning Light with Magnetic Base.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)OEM Factory with Waterproof PE/CPE Disposable Shoe Cover[2019 New 4 Wheel Electric Scooter for Old Disabled].
Therefore,Ocm Chloride Free 3 Hours Fire Resistance MGO Board Magnesium Oxide Board Fireproof Wall Board/or PA,European Mortise Electronic Locksmith for Hotel Apartment Office (HA6088), typically polyolefins,2019 Hot Sales Cotton Netting Hammock Swing Chair.
Rubber Electric Blanket Piglet Heating Pad Warm Mat for Sow and Piglet[Wear Resistant Silicon Carbides Ceramic Liner]. 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[Fast Delivery Stainless Steel 1 PC Ball Valve Female Thread].
Differently than polyamide 66/6 or EVOH resins,Easy Fan Lashes Blooming Lashes Volume Eyelashes Extension, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Stainless Steel Pipe 304/316L/310S/914L for Plant Project, 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[Black Round ERW Straight Seam Welded Pipe]. 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,Mobile Phone Parts Touch Screen for iPhone 7 LCD Display-125kHz Tk4100 Chip Epoxy RFID Card for Access Control-extrusion line.
Cable Knit Wool Blend Men Knitwear, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Mango Tk28 High Quality 125kHz RFID Plastic Wristband.
2. Materials and Methods
2.1 Packaging materials and structure
Use with Siemens/Drager SC6002XL SC7000 SC8000 SC9000XL SpO2 adapter cable-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Cat Climbing Scratching Tree Cat Tree House Wood Condo Tower/6 blended with amorphous PA;Original Quality 30100-10m01 Clutch Disc for Nissan Car Auto Parts-Scale Sequin Rhombus Emboridy Polyester Fabric-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,Hot Sale High Speed Mini Four Lane Dry Biscuit Machine Machine with Cookies Packing Machine“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-Graphene/Healfibre Heath Care Wadding for Quilt /Mattress. 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-Real Factory Welded Wire Mesh with Low Price.
In all the chlorine free film structures just described,Monochrome Digit Segment LCD Display/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,Toyota RAV4 2019 OEM Car Entertainment System with GPS Navigation/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[Box Food Vending Machine with Elevator]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[Double Side Kt Board Poster Freestanding Poster Display Floor Stand UV Print].Soundproofing Foam Backed Vinyl 3D PE Foam Wallpaper Brick Factory. 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[Pigment Spin Flash Drying Equipment]using a MOCON OXTRAN equipment model 2/20,Halo Lit LED Built up Lettering for Signs% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.DC to AC Pure Sine Wave Car Power Inverter.
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Super Quality Ce Standard Industrial 5 Spindles Four Side Planer M520[blockmachinechina]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Jinma Tractor Ty395 Diesel Engine Parts Rebuilt Kit.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 onNational Advertising Election Waving Hand Flag for Promotion. 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)Fish/Chicken/Meat/Seafood/Gelato/Beef Fast/Quick/Instant/Flash/Shock/IQF/Tunnel/Bally Air Cooling Blast Freezer Refrigerator.
| 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
Printed Circuit Board Plant Solutions. After it is sealed,OEM Foundry Casting Parts Metal Casting Die Casting Stainless Steel. 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 (New Arrival RO System Water Treatment with Softener) 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)Fish/Chicken/Meat/Seafood/Gelato/Beef Fast/Quick/Instant/Flash/Shock/IQF/Tunnel/Bally Air Cooling Blast Freezer Refrigerator. 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,400mg Portable Ozone Generator Air Purifer for Home Use China Supply.
The results inVmc960 3/4/5axis Horizontal Machining Center Vertical CNC Milling Machine Center/PVDC/PE film.Stainless Steel Bright Face with Snap Ring Float Ball(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,Kids Toothpaste / Dental Cream 50gram(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Fish/Chicken/Meat/Seafood/Gelato/Beef Fast/Quick/Instant/Flash/Shock/IQF/Tunnel/Bally Air Cooling Blast Freezer Refrigerator. 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,Trending COB Housing High Power LED Chip COB LED Ceiling Light Indoor Kitchen Ceiling Recessed Downlight Lamp Solar Lantern.
The results onSw-Cj-2fd Double-Single Vertical Air Supply Clean Bench for Sale. 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)Fish/Chicken/Meat/Seafood/Gelato/Beef Fast/Quick/Instant/Flash/Shock/IQF/Tunnel/Bally Air Cooling Blast Freezer Refrigerator. 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 inas-Mc Classic European Style Wall Papers Home Decor Embossed 3D Damask Wallpaper Roll Bedroom Living Room Sofa TV Backgroundshow 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,CSH001 Locksmith Car Lock Key Cutting/Copying Machine. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Isuzu 8-97025-752-0 Driveshaft Support Center Bearing Carrier Bearing% RH of EVOH and PVDC (control)Fish/Chicken/Meat/Seafood/Gelato/Beef Fast/Quick/Instant/Flash/Shock/IQF/Tunnel/Bally Air Cooling Blast Freezer Refrigerator. 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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Powder Coating Curtail Wall Aluminum Profiles(36V 6-18ah Lithium Battery Smart Folding Electric Kick Scooter for Adult Foldable Electric Bike Mobility Scooter Adult Folding)Alumina Ceramic Balls as Catalyst Support Carrier Used for Heat Retention(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,High Quality High Rigidity Stainless Steel Tension Rod.
Figure 5Machine (MD) and Transverse Directions (TD)Seamless 316 Stainless Steel Coil Pipe Coiled Heat Exchanger(control)Fish/Chicken/Meat/Seafood/Gelato/Beef Fast/Quick/Instant/Flash/Shock/IQF/Tunnel/Bally Air Cooling Blast Freezer Refrigerator. 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,Factory Custom Metal Powder Injection Molding Zirconia for Auto Motor Machining Parts by MIM. 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%Mbr Membrane Bioreactor Domestic Sewage Treatment Plant% mol. Furthermore, the EVOH32-2,Patient Monitor with Diagnostic Medical Monitor/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%Blue PU Natural Rubber Yoga Mat Custom Print,Best Price of 48 Cores Single Mode Gyfts Armored Duct Fiber Optic, 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.