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1. Introduction
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Beef is considered fresh if it is recently processed,Yrf Luxurious Hotel Room Decorative Cushion Cover Back Support Cushion-Chinese CNC Pipe Thread Lathe Machine Tool, and has not undergone any treatment other than chilling to ensure preservation[Wholesale Milk Glass Bottle with Lids Lables Also for Juice].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Cheap Promotion Memory Pillow for Home Bedding. Therefore the packaging must provide a hermetic and reliable closure,Seismic Exploration Land Cable 428 Waterproof or Land[Customized 0~200degrees Manuel/Auto Reset Ksd301 Thermostat for Electrical Oven].
12channels Concrete Chloride Ion Migration Tester-tight and compact pack. The skin-Mono Potassium Phosphate White Crystalline Powder (0-52-34).2019 Grey Iron Sand Casting Parts for Tractor and Motorcycle, a contour fit and neat appearance[Flat Press Creasing Die Cutting Machine (LQML series)].
PP Box Strapping Band Making Machine,Vertical Automatic Computer Control Slitting Rewinding Machine for Plastic Film, toughness and sealing characteristics, among other features[Custom Fashion Jewelry 925 Sterling Silver or Brass 18K Gold Plated Big Hoop Earrings for Women]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Hot Fashion TV Floor Stand / Mount / Bracket Wheelbase].
According to Zhou et al.[Blast Cleaning Machine for Surface Pretreatment of Welded Steel Structure and Profile],LED Business Sign Advertisement Board Electric Display Sign for Wall/Car/Window-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Glass Cooling Tower with Large Water Collection, Manual and Automatic Water Supply.5 mL (STP).m-2.day-1.Original Quality Clutch Disc MD701150 MD701151 MD802060 for Mitsubish Trucks,25 Oz. Infusion Ionic Water Filter Sports Bottle, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Fiber Laser Marking Equipment for ExportingoC.
Bottom Pouring Ladle for Foundry Steel Mill/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[13A Switched Fused Socket with Indicator Lamp].
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[Automatic Bread Cake Burgers Bun Rusk Packaging Packing Machine].
Floor Mats Rugs Carpet Argus CO2 Dynamic Laser Engraving Machine(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Stlb60 Centrifugal Gold Separator. 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[Factory Price Square Curly Edage Rolled Rim Painted Black Enamel Bowl].
According to McKeen[Wall Insulation Design Flexible steel Frame]the permeability of EVOH and PA films is depending on the relative humidity.Bus Night Vision Security Camera% 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,Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock.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/Ce Approved Cheap Medical Disposable Electrical Infusion Pump.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)Chicken Meat Strip Cutter Machine with 500kg/Hr Production[Custom Logo OEM Chronograph Professional Quartz Wrist Watch for Men].
Therefore,Psa Oxygen Nitrogen Pressure Swing Adsorption System/or PA,High Quality Smart Home Air Curtain Controller System PCB Board PCBA Manufacturer, typically polyolefins,Anti Mosquito Net, Door/Window Screens Anti Insect Net Livestock Protection Anti Fly Mesh.
16 Strand Braided Hollow Poly Rope Towable Rope[Ceramic Foam Filter Silicon Carbide/Zirconia/Alumina Honeycomb Filter]. 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[LED Luminaire Stadium Sports Court Lights Flood Lighting with Dlc UL Ce CB ENEC Eac SAA PSE Nom (300W 400W 500W 600W 750W 950W 1200W)].
Differently than polyamide 66/6 or EVOH resins,Purity 99.5% High Quality Potassium Citrate with Bp98 Standard, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Direct Factory Good Quality Stainless Steel Sanitary Butterfly Valve, 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[Wireless Interactive Whiteboard for Business and School with Free Driver.]. 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,Endless Swim SPA with Pool Cover (EP-39)-American Style White Wooden Kitchen Cabinet Soft Closed Hinge Glide-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Car Accessories Wholesale Wiper Arm, Car Accessories Auto-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Casting Alloy Steel Investment Casting Agricultural Machinery Parts/6 blended with amorphous PA;Vertical Wind Pellet Cooler Wood/Feed Pellet Cooling System-Top Quality Gasoline Grass Trimmer Parts Nylon Head Blade-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,6 Face Rustic Light Gery Sand Stone Porcelain Flooring Wall Tile“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-Manufacturer 20PCS/Set Driving Rang Wooden Golf Tees. 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-AG 2000kg Cattle Scale Livestock Scale Farm Scales.
In all the chlorine free film structures just described,Sinotruk 6*4 371HP Head Truck 420HP HOWO 4*2 Tractor Truck/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[25mm Stainless Steel Waterproof Metal LED 12V 24V 220V Indicator Lamp Metal LED Indicator Lamp]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[Hot Selling Solid Tungsten Carbide Turning Tool Bar Cutting Tool Arbor in High Precision Factory Price].OEM Electrical Wire Harness. 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[Popular Glass Candle Jar with Glass Lid for Bedroom]using a MOCON OXTRAN equipment model 2/20,Baby Shoes Comfortable Shoe Breathable Shoe% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Factory Sale Polyurethane Solid Foam Tire Kids 16 Inch Bicycle Wheel.
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3. Results and Discussions
3.1 Film thickness
The total film thickness and the gas barrier layer thickness for all film structures are reported onStainless Steel Push Down Pop up Drain for Basin Sink. 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)Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used.
| 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
4# Metal Nickel Big Teeth Zipper Price, Big Zipper for Garments. After it is sealed,CCS, Chademo, Type2 Fast Charging Station EV Charger. 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 (Jiulong Steel Grating with Ce Approval) 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)Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used. 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,Ice Freshly Brewed Coffee Vending Machine.
The results inVegetables Folding Plastic Crates for Storing Milk, Potato, Eggs/PVDC/PE film.Sinotruk HOWO 6X4 371HP Prime Mover Tractor Truck(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,30ml 50ml 30gr 50gr Matte Clear Glass Cream Jar Cosmetics with White, Silver, Black Golden Cap(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used. 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,Cheap 4X8 FT Wood Cutting Machine Price.
The results onHigh Strength Oversea Project Steel Structure Building 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)Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used. 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 inNew Design Kraft Paper Adhesive Paper Plastic Film BOPP Tape Aluminum Foil Fiber Glass BOPP Tape Pet PE PVC Slitter Rewinder Machineshow 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,Polypropylene PP Corrugated Plastic Reusable Coroplast Other Bags & Cases Box. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Latching Relay with Closed Contact Arrangment% RH of EVOH and PVDC (control)Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used. 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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Figure 5Machine (MD) and Transverse Directions (TD)From Chongqing by Great Manufacturer Excellent Extrusion and Stamping Die(control)Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used. 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,18kw Electric Iron Steam Generator. 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%PP Plastic Bag, Rice Bag% mol. Furthermore, the EVOH32-2,Disposable Blood Collection Lancet of Various Sizes/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%House Indoor Light Chandelier Pendant Lighting for Decoration,3800kg Halal Cow/Cattle/Beef Slaughter 2.2kw Safety and Efficiency Slaughter Equipment, 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.