Polyvinyl Chloride Wrap Research Articles

The fate of plastic wraps in constructed wetland: Surface structure and microbial community

The high use of plastic wraps leads to significant environmental pollution. In this study, the surface structure and microbial community evolution of commercially available plastic wraps [polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), and polylactic acid (PLA)] in constructed wetlands (CWs) were investigated. The results indicated that all plastic wraps gradually decreased in molecular weight, crystallinity, melting, and crystallization temperatures, whereas a gradual increase was observed in the surface roughness, polymer dispersity index (PDI), carbonyl index (CI) and Shannon index of microorganisms colonizing the CWs. The aging rate of the plastic wrap was in the order: PLA > PVC > PE > PVDC, at the same site in the CWs, and it was in the order: soil surface > plant roots > subsoil, for the same plastic wrap. The diversity of microorganisms colonizing the same plastic wrap was in the order: plant roots > subsoil > soil surface. The Shannon indices of microorganisms on plastic wraps were lower than those in the soil, indicating that the diversity of microorganisms colonizing plastic wraps is limited. Additionally, the microbial community structure on the plastic surface was co-differentiated by the plastic type, placement position in the CWs, and aging time. Significantly different microbial community structures were found on the PVC and PVDC wrap surfaces, revealing that the chlorine in plastics limits microbial diversity. Unclassified members of Rhizobiaceae and Pseudomonadaceae were the dominant genera on the surface of the plastic wraps, suggesting that they may be the microorganisms involved in plastic degradation processes. The study provides valuable perspectives to facilitate a comprehensive understanding of the migration, fate, and environmental risks associated with microplastics (MPs) in wetlands.

Comparison of postharvest quality of Aralia elata shoot according to packaging methods

In this study, we aimed to evaluate the quality of Aralia elata shoots according to different packaging methods during storage at 2°C. The highest level of dehydration and wilting incidences were observed in polypropylene containers with polyvinyl chloride wrap (PP+PVC), and these levels continually increased during the entire storage period, compared to other packaging methods. The overall marketability of A. elata shoot packaged in polyethylene terephthalate container (PET) and PP with the mineral-coted functional warp (PP+F) constantly declined during storage with a similar level of 38.6 and 36.0% at 15 days in storage, respectively. PP with PET cover packaging (PP+PET) showed the lowest decay and wilting rates during the entire storage, and the wilting score at 10th day was 51.9, 58.0, 51.8% suppressed, as compared to PET, PP+PVC, and PP+F, respectively. Consequently PP+PET packaging effectively decreased the deterioration of A. elata and maintained marketability for 10 days of storage at 2°C.

Evaluation of the Effects of Different Packaging Materials on the Quality Attributes of the Tomato Fruit

Post-harvest loss continues to be a significant problem in the food industry. Different packaging materials, designed to reduce fruit damage, are anticipated for various applications in the supply chain. Recently, stamped paper (SP) and expandable polystyrene (EPS) trays have been introduced as tomato retail packaging. Although the combination of paper trays and clear plastic are still not 100% biodegradable packaging, they are promising alternatives to the heavy utilisation of petrochemical-based polymers. This study investigated the effects of different packaging materials and storage conditions on the ‘Nema-Netta’ tomatoes’ quality attributes. The treatments consisted of a stamped paper (SP) + polyvinyl chloride (PVC), expandable polystyrene (EPS) + polyvinyl chloride (PVC), stamped paper (SP)+ flow wrap, expandable polystyrene (EPS) + flow wrap, polypropylene (PP), and unpackaged tomatoes stored at cold and ambient conditions. Firmness, physiological weight loss (PWL), pH value, titratable acidity (TA) and total sugars were evaluated at seven-day intervals, over 28 days. Temperature and relative humidity at cold storage ranged between 8–12 °C, 78–80% RH and 22–26 °C, 68–72% RH at ambient storage conditions. The packaging and storage conditions significantly affected the PWL, firmness, pH, TA and total sugars. Samples in the EPS Tray combined with the PVC wrap at cold storage maintained the quality of the tomatoes better than the other packaging. The combination of packaging and cold storage created an ideal environment for maintaining the quality of tomatoes. The relative differences between EPS Tray + PVC (non-biodegradable) and SP Tray + PVC (biodegradable) were less than 5% in multiple tests.

Migration of epoxidized soybean oil from polyvinyl chloride/polyvinylidene chloride food packaging wraps into food simulants.

Epoxidized soybean oil (ESBO) has been used in polyvinyl chloride (PVC)/polyvinylidene chloride (PVDC) food packaging cling film as a plasticizer and stabilizer. The aim of this study was to investigate the migration of ESBO from PVC/PVDC cling film, based on gas chromatography mass spectrometry (GC-MS). The specific migration of ESBO was evaluated using various food simulants (water, 4% acetic acid, 50% ethanol and n-heptane) for PVC and PVDC wrap products. ESBO did not migrate into water and 4% acetic acid for all the tested samples. However, it was released into 50% ethanol and n-heptane in several PVC/PVDC wraps, with maximum migration levels of 38.4 ± 0.7 and 37.4 ± 0.8μg/mL, respectively. These results demonstrate that ESBO is capable of being released from PVC/PVDC wrap into amphiphilic/oily food and its migration should be regularly monitored.

토마토와 파프리카의 포장실태조사 및 포장재 종류에 따른 품질변화

This study aimed to evaluate the commercialized packaging status of tomato and paprika, and to investigate theeffect of different packaging materials on the quality of tomato and paprika during storage. Packaging statuses were surveyed at a department store, wholesale market, and supermarket in Seoul, Korea. Materials used for packaging tomato and paprika were cartons, polypropylene (PP), low-density polyethylene (LDPE), polystyrene (PS), and polyvinyl chloride (PVC). Tomato and paprika were packaged by using corrugated boxes, Styrofoam trays, PP film, and PVC film. The weight loss and hardness of non-packaged tomato and paprika were significantly different after 48 hr to the initial values (p<0.05). Box-packaged tomatoes had the lowest pH values and showed significantly higher soluble solid contents (p<0.05). However, there were no significant differences in among other packaging materials. For paprika, the ΔE values of PVC wrapping were higher than those of other packagings. Hence, the results demonstrated that a corrugated box with PP film and PP film bags with four holes plus wire-tying were most able to maintain the overall qualities of tomato and paprika, respectively, during storage.

유통 중 신선편이 버섯 제품의 포장실태 및 관능적 품질 조사

This study investigated the packaging status and sensory quality of fresh-cut mushroom products from retail markets. Fifty one fresh-cut mushroom products were surveyed / purchased from discount stores in four cities in January (winter), March (spring), August (summer), and October (autumn) 2009. Collected fresh-cut mushrooms include single variety products like whole oyster mushroom and winter mushroom, diced or sliced oak mushroom, sliced king oyster mushroom, and ready-to-cook mixed mushroom products. Most fresh-cut mushrooms were packed in trays made of aluminum, polystyrene (PS), polyethylene terephthalate (PET), nylon materials covered with PVC (polyvinyl chloride) wrap or solid PP (polypropylene) and PS. Eighty nine percent of the covers were labeled with manufacture and expiration date. Collected samples showed severe browning (10%) and off-flavor (4%). The percentage of products with a rating of `good` or better in overall quality was 90%. Moreover, Survey showed seasonal differences in sensory qualities. All of the collected fresh-cut mushrooms in autumn and winter had high marketability. However, Mushroom products collected in spring and summer had lower quality, hence requires treatment to prevent browning and off-flavor.

Effects of corn distillers dried grains with solubles on quality traits of pork1,2,3

The high cost of feed grains has led swine producers to seek alternative feedstuffs, such as distillers dried grains with solubles (DDGS). However, little is known about the effects of high levels of DDGS in swine diets on pork quality. The objective of this study was to evaluate belly processing and bacon, sausage, and loin quality of pigs fed high levels of DDGS. Sixty pigs averaging 34 kg BW were fed fortifi ed corn-soybean meal diets containing 0%, 15%, 30%, or 45% DDGS. At 120 kg BW, the pigs were humanely harvested and bellies, loins, and shoulders were removed from the left side of each carcass. Flex tests of bellies indicated that they became softer (linear, P < 0.03) as DDGS levels increased. The PUFA in backfat and belly fat increased linearly (P < 0.005), as did iodine values with increasing 0DDGS in the diet. Bellies were pumped to target 12% brine retention, cooked, and sliced at a commercial facility. Slicing yield was not affected by DDGS level fed. Fresh bacon slices were scored 1 to 6 with 1 representing no visible cracks in the fat and 6 representing a spider weblike shattering of the fat. Shatter scores decreased (linear, P < 0.001) with increasing dietary DDGS. Bratwurststyle sausage was produced by combining ground Boston butts and picnics to target 30% fat, blended with commercial seasonings, and stuffed into natural casings. Loose sausage was placed on trays, overwrapped with polyvinyl chloride wrap, and stored under constant, cool white fl orescent lighting (1,300 lx) at 4°C. Objective color values (L*, a*, and b*) were taken on loosepackaged sausage mix at 6 locations at the same time daily for 7 d. Sausage was also sampled for thiobarbituric acid reactive substances (TBARS) at the same time daily on d 0, 3, 5, and 7. Color scores of sausage were not consistently affected by DDGS level in the diet and the changes were slight. The TBARS in sausage from pigs fed the 30% and 45% DDGS diets increased to a greater extent from d 0 to 7 than in those fed the control or 15% DDGS diets. An 8-member, trained panel evaluated the sensory attributes of bacon slices, sausage, and loin chops. The DDGS resulted in a softer texture (P < 0.004) and increased juiciness (P < 0.04) in sausages, but no differences in sensory scores were found in bacon slices or loin chops. The results indicate that the softer bellies, greater concentrations of PUFA in carcass fat, and greater iodine values associated with feeding increased DDGS did not negatively affect slicing yield of cured bellies, quality of fresh bacon slices, or eating quality of bacon, sausage, or loin chops.

Influence of cross-infection control methods on performance of pen-type laser fluorescence in detecting occlusal caries lesions in primary teeth

The aim of this in vitro study was to determine the influence of cross-infection control methods, as probe tip autoclaving and polyvinyl chloride (PVC) wrapping, on the performance of laser fluorescence device (DIAGNOdent pen--LFpen) on occlusal surfaces of primary molars. One experienced examiner carried out all examinations (n = 78). For the probe tip autoclaving study, 62 sites (sample A, 40 teeth) were used. The sites were assessed with LFpen using tips in six different conditions: without autoclaving and after autoclaving for 10, 20, 30, 40, and 50 cycles of 10 min. For the PVC wrapping study, we selected other 58 sites (sample B, 38 teeth). The sites were assessed with the LFpen device in two conditions: with and without PVC wrapping. The teeth were sectioned and histologically assessed for caries depth. LFpen values, sensitivity, and specificity were compared among the different conditions. The LF readings were slightly higher after successive examinations, independently of autoclaving. In both studies, no statistical differences in the sensitivity and specificity were observed for all conditions. In conclusion, probe tip autoclaving and PVC wrapping do not influence the performance of LFpen device on occlusal surfaces of primary molars.

The Influence of PVC Wrapping on the Performance of Two Laser Fluorescence Devices on Occlusal Surfaces in Vitro

The aim of this study was to determine the influence of polyvinyl chloride (PVC) wrapping on the performance of two laser fluorescence devices (LF and LFpen) by assessing tooth occlusal surfaces. Protection of their tips may influence LF measurements. To date there are no studies evaluating the influence of this protection on the performance of the LFpen on permanent teeth, or comparing it to the original LF device. One hundred nineteen permanent molars were assessed by two experienced dentists using the LF and the LFpen devices, both with and without PVC wrapping. The teeth were histologically prepared and assessed for caries extension. The LF values with and without PVC wrapping were significantly different. For both LF devices, the sensitivity and accuracy were lower when the PVC wrapping was used. The specificity was statistically significantly higher for the LFpen with PVC. No difference was found between the areas under the ROC curves with and without PVC wrapping. The ICC showed excellent interexaminer agreement. The Bland and Altman method showed a range between the upper and the lower limits of agreement of 63.4 and 57.8 units for the LF device, and 49.4 and 74.2 for the LFpen device, with and without PVC wrapping, respectively. We found an influence of the PVC wrapping on the performance of the LF and LFpen devices. However, since its influence on detection of occlusal caries lesions is considered for, the use of one PVC layer is suggested to avoid cross-contamination in clinical practice.

ラップフィルムおよびキャップシーリング中のエポキシ化大豆油およびエポキシ化亜麻仁油の分析

A determination method was developed for epoxidized soybean oil (ESBO) and epoxidized linseed oil (ELO), which are used as plasticizers and/or stabilizers, in wrapping film and cap sealings. The ESBO method reported by Castle et al. was improved. Samples were extracted with acetone-hexane (3: 7), transmethylated under alkaline conditions, then derivatized to the 1,3-dioxolanes and analyzed by GC/MS. The recoveries of spiked ESBO and ELO were between 92.6% and 104.4%. The determination limits were 0.01 mg/g for ESBO and 0.02 mg/g for ELO in the wrapping film, and 0.04 mg/g and 0.08 mg/g in the cap sealing. ESBO and ELO were surveyed in 10 samples each of wrapping film and cap sealings currently available on the Japanese market. ESBO was found at 34.7-82.8 mg/g in polyvinyl chloride (PVC) wrapping films and at 5.47-399 mg/g in cap sealings. ELO was detected at 8.6-11.4 mg/g in polyvinylidene chloride (PVDC) wrapping films, and at 46.4 mg/g in a PVC wrapping film.

Effects of Modified Atmosphere Packaging on Selected Phenomena Affecting Quality of Fresh, Edible Bamboo Shoots

Changes in phenomena affecting quality of fresh bamboo shoots ( Dendrocalamus asper, Schultes f. ) due to modified atmosphere packaging were evaluated. After harvest bamboo shoots were peeled, and stored in the open (unpacked) or packaged in polyvinyl chloride wrap (thickness 5µm) or polypropylene bags (thickness 15 µm) at two different temperatures (9 and 28 o C) and shelf life was determined. Unpacked samples had very high weight losses (5% per day) at both temperatures limiting their shelf life to less than 2 days. Both types of packaging reduced water loss significantly (polyvinyl chloride: 0.5% per day at both temperatures, polypropylene: 0.09% and 0.14% at 9 and 28 o C respectively). Samples stored at room temperature started to discolor within 1-2 days while packed samples in the refrigerator showed the first signs of discoloration only after 5-7 days of storage. Refrigeration was also effective to inhibit fungal growth. Our results show that application of cold storage or packaging alone yield no, or only a limited extension of shelf life but their combined application yields a shelf life extension till 2 weeks.

Additives in Polyvinyl Chloride and Polyvinylidene Chloride Products

The residue of 89 kinds of additives including plasticizers in polyvinyl chloride (PVC) and polyvinylidene chloride (PVDC) products were investigated. PVC wrapping films contained 14-38% of plasticizers, most of which were adipates, especially diisononyl adipate. However, few additives were observed in PVC containers. PVC gloves contained 34-55% of plasticizers, mostly di-2-ethylhexyl phthalate and di-2-ethylhexyl adipate, in all samples. The levels of plasticizers in toys were 8.7-45%, consisting mainly of diisononyl phthalate and di-2-ethylhexyl phthalate. On the other hand, the levels of plasticizers in PVDC wrapping films were only 2.7-7.8% (O-acetyl tributyl citrate and dibutyl sebacate). Nonylphenol was found in some PVC wrapping films, gloves and toys at concentrations of about 530-5, 500μg/g sample.

A simple estimation method for the embryonic toxicity of plastic wrapping sheets using an egg shell-free culture system of chick embryos.

To estimate the embryonic toxicity of food wrapping films, the shell-free chick embryos were cultured using plastic wrapping sheets like a suspending hammock. Polyethylene (PE) wrapping sheets with no additives showed much higher survivability than polyvinylchloride (PVC) wrapping sheets including plasticizers. Furthermore when a PVC wrapping sheet was autoclaved at 110 degrees C for 30 min, the embryonic survivability significantly decreased compared with the untreated PVC wrapping sheet. These observations suggest that the egg shell-free culture method using a plastic wrapping sheet is a useful estimation method for the embryonic toxicity of food wrapping film.

Respiratory effects of work in retail food stores. II. Respiratory symptoms.

This study examined the relationships between the prevalence of respiratory tract symptoms and estimates of environmental exposures in retail food stores, in particular exposures to emissions from the cutting of polyvinyl chloride wrap. When respiratory symptoms were compared with a measure of cumulative exposure, there was evidence that the prevalence of symptoms of episodic airway narrowing was higher for workers who had been exposed directly or indirectly to meat wrapping operations independent of a significant association of these symptoms with allergic or asthmatic history. Whether this finding reflects a nonspecific irritant effect or allergic sensitization cannot be determined from these data. No single substance present in the work environment studied has, as yet, been identified as associated with these effects.

Evaluation of Emissions from Simulated Commercial Meat Wrapping Operations Using PVC Wrap

Meatwrapper's asthma is an elusive health problem with a suspected relationship to exposure to emissions from polyvinyl chloride (PVC) film cut with a hot wire. A study was conducted to determine how the type of wrap cutter (wire or rod) and its temperature affected the emissions from a simulated occupational wrapping process. The cutting temperatures covered the same range as was measured in Boston retail food stores. A commercial wrapping machine and samples of commercial PVC meat and produce wraps were used. Seventy five percent of the particulate from the hot wire was respirable, and the quantity of emissions was a strong function of the film tension and cutting technique. Particulate emissions did not increase steadily with increasing wire temperature, but plateaued or declined at high temperatures. Particulate emissions from the rod cutter were very low at low temperatures, but exceeded those of the wire at temperatures above 200°C. The particulate was 100% dioctyl adipate (DOA, the plasticizer in the wrap) with wire temperatures below 200°C, and was approximately 80% DOA for temperatures above this. Gaseous HC1 was not detected in emissions from a hot wire operated below 150°C, but HC1 emissions increased rapidly to a plateau for temperatures above 200°C. Approximately 20% of the HC1 produced at temperatures above 200°C was associated with the particulate, which appeared to act as a carrier and transport the HC1 through water filled impingers. Field tests are needed to determine if particulate produced in the workplace may also behave as a carrier for HC1.

Evaluation of emissions from simulated commercial meat wrapping operations using PVC wrap.

Meatwrapper's asthma is an elusive health problem with a suspected relationship to exposure to emissions from polyvinyl chloride (PVC) film cut with a hot wire. A study was conducted to determine how the type of wrap cutter (wire or rod) and its temperature affected the emissions from a simulated occupational wrapping process. The cutting temperatures covered the same range as was measured in Boston retail food stores. A commercial wrapping machine and samples of commercial PVC meat and produce wraps were used. Seventy five percent of the particulate from the hot wire was respirable, and the quantity of emissions was a strong function of the film tension and cutting technique. Particulate emissions did not increase steadily with increasing wire temperature, but plateaued or declined at high temperatures. Particulate emissions from the rod cutter were very low at low temperatures, but exceeded those of the wire at temperatures above 200 degrees C. The particulate was 100% dioctyl adipate (DOA, the plasticizer in the wrap) with wire temperatures below 200 degrees C, and was approximately 80% DOA for temperatures above this. Gaseous HCl was not detected in emissions from a hot wire operated below 150 degrees C, but HCl emissions increased rapidly to a plateau for temperatures above 200 degrees C. Approximately 20% of the HCl produced at temperatures above 200 degrees C was associated with the particulate, which appeared to act as a carrier and transport the HCl through water filled impingers. Field tests are needed to determine if particulate produced in the workplace may also behave as a carrier for HCl.