Plastic Film Bags Research Articles

Quality of frozen semi-finished products from pear fruit for the application of edible coating

The article presents the results of studies of the quality of frozen semi-finished products from pears with edible pectin coating depending on the concentration of the pectin solution and the storage time. Frozen semi-finished products were produced from Duchesne pear fruits according to the generally accepted technological instructions by cutting the fruits into 20x20 mm particles, followed by blanching in a 0.1 % citric acid solution at 85 °C for 2–5 minutes and drying. The prepared pear particles were immersed in a pectin solution with a concentration of 1, 2, 3, 4, 5 % for 1 min, followed by drying. Semifinished pear products were frozen at a temperature of minus 30 ± 1 °C, packed in plastic film bags weighing up to 0.5 kg and stored for six months at minus 18 °C. The quality of the products was assessed by changes in physical and organoleptic parameters. The cryoresistance of frozen semi-finished pear products ranged from 93.5 % to 95.7 %. A reliable dependence of the cryoresistance of frozen semifinished products on the concentration of pectin solution and the duration of storage was established, with the maximum value of the studied indicator in samples coated with a 5 % pectin solution and its decrease during storage. The weight loss of semi-finished products during freezing amounted to 1.5–2.1 % by weight, with maximum losses in uncoated semi-finished products, and during storage – 0.5–0.6 %. The dependence of semi-finished products weight loss on the presence of a coating was proved, with maximum losses in the control during freezing. A significant effect of the coating on the organoleptic quality indicators of semi-finished products was found, in particular, improvement of appearance, consistency and color with a maximum score of 4.4 points in samples coated in a 5 % pectin solution. The application of edible pectin coating on pear semi-finished products before freezing contributed to an increase in their cryo-resistance by 0.5–2.5 %, and the overall organoleptic score by 0.2–0.6 points with 0.1–0.6 % lower weight loss. Key words: edible coating, freezing, semifinished products, quality, cryo-resistance, weight loss.

Comparison of Three Cooling Methods (Hydrocooling, Forced-Air Cooling and Slush Icing) and Plastic Overwrap on Broccoli Quality during Simulated Commercial Handling

Broccoli is a highly perishable crop, due to its high respiration rate, and rapidly loses quality under inappropriate handling temperatures. The objective of this study was to evaluate the effect of commercial hydrocooling (HY), forced-air cooling (FA) or slushed-ice cooling (SI) on the quality and shelf-life of two commercial broccoli cultivars (‘Marathon’ and ‘Eastern Crown’) grown in northeast Florida during the early spring season. Following HY and FA, individual bunches (‘Marathon’) or crowns (‘Eastern Crown’) were placed in plastic film bags and stored at 1 °C for 7 days then transferred to 5 °C for 8 days to simulate retail conditions. It was found that HY removed the field heat 3.6 and 4.8 times faster than FA and SI, respectively. For both cultivars, using a texture analyzer, broccoli cooled by SI were softer (20.4 to 27.9 N) with higher head deformation than those by HY or FA (45.6 to 58.9 N) after 15 days of storage. Overall appearance of both cultivars decreased during storage if infected in the field by the fungal pathogen Alternaria brassicicola, which causes black spot disease. However, by the end of storage ‘Eastern Crown’ had a higher quality rating (6.2) than ‘Marathon’ (5.4). Broccoli floret moisture content was not affected during storage; however, ‘Marathon’ had higher moisture content (94.7%) than ‘Eastern Crown’ (89.2%). Yellowing was expressed more for ‘Marathon’, which had higher chroma* value (21.4) and lower hue* angle (h*) (122.3) value than ‘Eastern Crown’ after 7 days at 1 °C, plus 8 days at 5 °C. Carotenoid content was similar for both cultivars at harvest (2.3 mg/100 g) then decreased 39% for ‘Marathon’ and 12% for ‘Eastern Crown’ by day 15. Total chlorophyll was similar for both cultivars throughout storage (22.6 mg/100 g). Ascorbic acid decreased for both cultivars during storage but was higher in ‘Eastern Crown’ (92.0 to 101.9 mg/100 g) compared to ‘Marathon’ (80.7 to 88.6 mg/100 g). Hydrocooling and forced-air plus overwrapping have potential to reduce cooling costs during commercial handling.

FUZZY MODELING FOR RAPID COOLING OF TABLE GRAPES IN DIFFERENT PLASTIC FILM BAGS

Rapid cooling is necessary to remove heat from fruit; however, it directly affects the water loss of grapes under certain conditions. Fuzzy logic is an important theory for analyzing results as it simplifies the assimilation of the phenomena through refined adjustments, allowing the prediction of the weight loss of fruits in relation to rapid cooling conditions. The objective of this study was to develop a fuzzy model that could predict weight loss as a function of the rapid cooling of table grapes in different plastic film bags. Modeling was performed using three types of plastic film bags (micro-perforated, macro-perforated, and non-perforated) at three levels of palletization (lower, intermediate, and upper), arranged in an experimental design in randomized blocks, in a 3 × 3 factorial scheme, with three blocks. The influence of the relative humidity and amplitude of humidity on the variable weight loss percentage of the Arra 15 grape variety was measured. The average percentage error of the fuzzy model was 9.78%. The intermediate level alone showed an error of 4.02%. Thus, the developed fuzzy model provided a good prediction of the weight loss of table grapes.

Plastic film bags on the refrigeration of table grapes

Plastic film bags on the refrigeration of table grapes

Fermentation quality of Pennisetum purpureum cv. Mott ensiled with Lactobacillus plantarum and sugarcane molasses in tropic

Fermentation quality of Pennisetum purpureum (Schumach) cv. Mott ensiled with Lactobacillus plantarum [(Orla-Jensen) Bergey et al.] and sugarcane molasses in tropical condition was evaluated. Approximately 100 g portion of wilted material chopped into 20 mm lengths packed into plastic film bags and sealed with a vacuum sealer. T0 was untreated silage, T1 silage with 50 μL L. plantarum without molasses, and T2, T3, and T4 treated silage with 50 μL L. plantarum and 1 %, 2 %, and 3 % molasses respectively. The bag silos were stored in room temperature (average 25 °C) for 30 d of incubation. This study showed the chemical characteristics were not significantly differ among treatments, eventhough T3 and T4 showed higher organic matter (OM) and water soluble carbohydrate (WSC) contents, meanwhile the highest crude protein (CP) was reached in T3. In general, molasses increased population of lactid acid bacteria (LAB) and decreased pathogen (coliform and aerob bacteria). The favour pH for silages (< 4) were only reached in addition 2 % and 3 % of molasses. It could be concluded that in tropical condition, L. plantarum it self could not improve silage quality. Addition 1 % to 3 % molasses improved silage quality, so that molasses were needed to improve fermentation quality of the grass silage with L. plantarum inoculation.

Effects of locations and growth stages on nutritive value and silage fermentation quality of Leymus chinensis in Eurasian steppe of northern China

AbstractThe objective of the study was to determine the correlation among location of sampling sites, characteristics of Leymus chinensis material and fermentation quality, to examine the effect of growth stage on nutrient composition and fermentation quality, and then to find the main factors for influencing fermentation quality and the optimum harvest stage for ensiling. L. chinensis was harvested from 27 sites in Eurasian steppe of northern China, chopped, ensiled in plastic film bags, and stored in dark for 60 days. Lactic acid bacteria (LAB), fermentation characteristics and nutrient composition were analyzed. The results showed that crude protein (CP) of L. chinensis was &gt;80 g kg–1, and average of neutral detergent fiber and buffering capacity (BC) were 661 g kg–1 and 227 mE kg–1 respectively. The LAB number of silage was &lt;108, the pH &gt;4.50, and the average of lactic acid (LA) and acetic acid (AA) were 5.14 and 9.72 g kg–1 respectively; and V‐Score &gt;80. The water‐soluble carbohydrate (WSC) of L. chinensis correlated negatively with latitude (P &lt; 0.001) and positively with elevation (P &lt; 0.01) of sits based on dry matter (DM) and fresh weight (FW), and CP correlated negatively with latitude (P &lt; 0.05) based on FW. The latitude and elevation of sites correlated significantly (P &lt; 0.05) with LA, LA/AA and ammonia nitrogen/total nitrogen (AN/TN) in L. chinensis silage, and the DM and hemicellulose of material had significant correlation with propionic acid (P &lt; 0.05) and AN/TN (P &lt; 0.05) of L. chinensis silage based on DM and FW. L. chinensis had lower CP (P &lt; 0.05) and BC (P &lt; 0.05), and higher cellulose (P &lt; 0.05) with advancing growth stage; the silages harvested at boot stage were well fermented compared with heading and flowering stages. Those results indicated that L. chinensis is a good forage for ruminants, L. chinensis silage is well preserved, there are negative effect of latitude and positive effect of elevation on the WSC in L. chinensis, and the latitude and elevation of sites, and the DM and hemicellulose of material are main factors of affecting the fermentation quality of L. chinensis silage. The optimum harvest stage for ensiling L. chinensis is boot stage.

Quality Evaluation of Short-grain Brown Rice During Storage as Affected by the Combined Action of Initial Moisture Content, Storage Temperature, and Packaging of the Kernels

The short-grain rice cultivar Choochung with a rough rice moisture content of 21% was air-dried to equilibrate the moisture content to 15, 16, and 17%. After dehulling, brown rice was packaged for storage in laminated paper or LDPE/OPP plastic-film bags (10-kg size). After storage of the packaged rice kernels in plastic and paper bags at 10, 15, and 20℃, the quality characteristics of the rice were evaluated weekly for 16 weeks. Serious losses in the internal moisture content of the kernels were observed during storage in paper bags, regardless of the moisture content of the kernels or the storage temperature. The plastic-film packaging was effective in maintaining the weight of the kernels for all treatments, but severe fat oxidation problems were encountered, especially when the initial moisture content of the kernel was 17% and/or the storage temperature of the kernels was 20℃. Before two weeks, the fat acidity value of the kernels reached 20 mL KOH/100 g, a marginal limit for an acceptable taste of cooked rice. Based on this study, the recommended environment for the storage of brown rice for efficient economic storage of the kernels is an initial kernel moisture content of 16%, laminated plastic-film packaging, and a sub-refrigeration temperature of 15℃.

10404 落下衝撃を受ける液体内包フレキシブル注ぎ口付き袋内の圧力(OS1-1【実験力学とその応用(1)】)

Recently, a new container for liquid of food products, which consists of a case made of a sheet of plastic or paper and a liquid-packing bag with a pouring lip made of a plastic film has been developed. The improvement of the resistance of the new container to drop impact is desired because the resistance is not adequately. To improve the resistance, it is important to investigate the pressure in liquid-packaging bags. In this study, the pressure in liquid-filled plastic film bags with a pouring lip and a heat-sealed area to reinforce the lip subjected to drop impact is measured using a pressure sensor. Results indicated that the heat-sealed area strongly affects the pressure in the bags.

Inactivation of Listeria innocua, Salmonella Typhimurium, and Escherichia coli O157:H7 on Surface and Stem Scar Areas of Tomatoes Using In-Package Ozonation

A novel in-package ozonation device was evaluated for its efficacy in inactivating three microorganisms (viz., Listeria innocua, attenuated Salmonella Typhimurium, and Escherichia coli O157:H7) on tomatoes and for its effect on fruit quality. The device produced ozone inside sealed film bags, reaching a concentration of 1,000 ppm within 1 min of activation. The three bacterial cultures were inoculated onto either the smooth surface or the stem scar areas of the tomatoes, which were then sealed in plastic film bags and subjected to in-package ozonation. L. innocua on tomatoes was reduced to nondetectable levels within 40 s of treatment on the tomato surface, with inactivation of ca. 4 log CFU per fruit on the stem scar area. An increase in treatment time did not result in a proportional increase in bacterial reduction. For E. coli O157:H7 and Salmonella, there was little difference (<1 log) in the effectiveness of the system when comparing surface and scar-inoculated bacteria. Both bacteria were typically reduced by 2 to 3 log CFU per fruit after 2- to 3-min treatments. No negative effects on fruit color or texture were observed during a 22-day posttreatment storage study of ozone-treated tomatoes. These results suggest that the three bacteria responded differently to ozonation and that in-package ozonation may provide an alternative to chemical sanitizers commonly used by the industry.

Variation in Pressure in Liquid-Filled Plastic Film Bags Subjected to Drop Impact

The side-wall pressure in liquid-filled plastic film bags subjected to drop impact was measured using pressure sensors, and the relationship between the variation in pressure with time and the number of heat-sealed sides of the bag was investigated. The two samples A and B [130 © 300mm 2 (width © height)] made of transparent plastic film of 67µm thickness were used. Sample A was a liquid-packaging bag heatsealed at four sides, and sample B heat-sealed at three sides. The bags contained about 1,000mL of liquid. Pressure sensors were placed at 26 positions along the inner wall surface of the bag. The samples were held at a height of 0.5m and freely dropped onto wood floor, aluminum alloy, rubber and sponge plates on a concrete floor. The bottom drop test was carried out. Results indicate that the propagation speed of pressure is affected by the number of heated-sealed sides of the bag, and the maximum pressure by the type of floor material. [doi:10.2320/matertrans.I-M2011844]

Ensiling and in vitro digestibility characteristics of Ceratoides arborescens treated with lactic acid bacteria inoculants and cellulase

The effects of different additives, including lactic acid bacteria inoculants, acremonium cellulase and mixtures of lactic acid bacteria inoculants and acremonium cellulase on changes of nutritive components and in vitro digestibility of Ceratoides arborescens during ensiling were investigated. The silages of each treatment were prepared in plastic film bags, kept in an incubator at 30°C and bags were opened after 1, 3, 5, 10, 30 and 45 days at room temperature. The results show that addition of additives and ensiling time did not affect acid detergent lignin content during ensiling (P>0.05). With ensiling time, pH value decreased ( P<0.05), whereas the concentrations of lactic acids, acetic acid, propionic acid, butyric acid and ammonia nitrogen increased (P<0.05). At 45 days of fermentation, the silages treated with the mixture of 50 mg lactic acid bacteria and 200 mg acremonium cellulase showed the lowest ( P<0.05) pH value, neutral detergent fiber and acid detergent fiber contents, and the highest (P<0.05) in vitro digestibility of neutral detergent fiber and acid detergent fiber, water soluble carbohydrate and lactic acids concentrations compared to other treatments. Lactic acid bacteria can improve C. arborescens silage fermentation quality; cellulase had a positive effect on in vitro digestible of neutral detergent fiber. There was favorable interaction between the addition of lactic acid bacteria and cellulase on the silage fermentation quality and chemical composition of C. arborescens .

Effect of fruit bagging with different spectra bags on the growth and quality of tomato in spring-summer season

The effect of fruit truss/bagging with five different spectra bags on the micro-environment,fresh weight,yield,nutrition content and physiological disease of tomato fruit in spring-summer season was investigated.The results show that under bagging,light intensity significantly weakens,especially ultraviolet wave( 400 nm),while 400～600 nm radiation drops sharply in red plastic film bags(RFB).Relative humidity generally increases while temperature change is different in different bags.No significant differences in the rate of increase in fresh fruit weight,fruit rigidity,fruit shape,single fruit weight and fruit weight per truss(bag) exist.Fruit ripening is quickened and concentrated,and lycopene content increases but with no significant difference in vitamin C,free amino acids and soluble protein content after fruit bagging.Soluble solid content decreases significantly in fruits with fresh film bag(FFB),while soluble sugar content reduces most significantly in fruits with RFB,yet that of organic acid decreases markedly in fruits with white plastic film bag(WFB).The number of deformed fruits,holed fruits and black-scar fruits decreases while cracked fruits increase and stalk-enlarged fruits appear in fruit bagging treatments.It is concluded that bagging of fruits in spring-summer season is beneficial to the growth and ripening of tomato fruit.The types of bag most suitable include purple plastic film bag(PFB) followed by WFB.

The use of molecular sieves to simulate hot lesions in 18F-fluorodeoxyglucose—positron emission tomography imaging

We investigated the use of a kind of zeolite, the Bowie chabazite, to produce radioactive sources of different shapes, dimensions and activity concentrations that can be used for lesion simulation in positron emission tomography (PET) imaging. The 18F-fluorodeoxyglucose (18F-FDG) uptake of a group of 12 zeolites was studied as a function of their weight (120–1520 mg) and of the activity concentration of the 18F-FDG solution (1–37 MBq ml−1), using a multiple linear regression model. The reproducibility, homogeneity and stability over time of the 18F-FDG uptake were assessed. The fit of the regression model is good (r2 = 0.83). This relation allows the production of zeolites of a desired 18F-FDG activity using knowledge of the concentration of the soaking solution and the weight of the zeolite. The reproducibility of the 18F-FDG uptake after heating the zeolites is elevated (CV% = 3.68). The almost complete regeneration of the zeolites allows us to reuse them in successive experiments. The stability of the 18F-FDG uptake on zeolites is far from ideal. When placed in a saline solution the ‘activated’ zeolites release the 18F-FDG with an effective half-time of 53 min. The sealing of the zeolites in plastic film bags has been demonstrated to be effective in preventing any release of 18F-FDG. These features, together with their variable dimensions and shapes, make them ideal 18F-FDG sources with a fixed target-to-background ratio that can be placed anywhere in a phantom to study lesion detectability in PET imaging.

21304 落下衝撃を受ける液体内包プラスチックフィルム袋内の液体挙動(材料強度と実験力学(1),OS.3 材料強度と実験力学,学術講演)

The behavior of liquid in plastic film bags contained fluid subjected to impact loads due to dropping was investigated using a visualization technique. The bag contained about 100 to 700 ml of liquid. The liquid consisted of water and ethanol. Particles of about 3mm in diameter made of polyethylene were included in the liquid to visualize movement of liquid in the containers. The containers were subjected to impact due to dropping, and photographs of the containers were taken using a high speed camera. Results indicated that the bags have characteristic behavior of liquid in the bags.

훈건 굴을 이용한 분말조미소재의 가공 및 품질안전성

This study was conducted to evaluate the optimal processing conditions of smoke-dried powdered oysters and to determine their shelf-life during storage for development of a natural oyster flavoring substance. The optimal conditions for processing of smoke-dried oyster powder with freshy oyster were as follows. Raw shelled oysters were rinsed with 3% saline solution, drained, boiled for 10 minutes at <TEX>$98^{\circ}C$</TEX>, and then smoked for 1 hour at <TEX>$50^{\circ}C$</TEX>, followed by drying for 4 hours at <TEX>$80^{\circ}C$</TEX> Smoke-dried oyster powder with oyster scraps were prepared as flavoring material. The smoked oyster scraps were submerged in oyster sauce far 10 minutes at room temperature and then dried with hot air for 5 hours at <TEX>$50^{\circ}C$</TEX>. The smoke-dried oysters and smoke-dried oyster scraps were then pulverized to 50 mesh and packed in tea bags or vacuum-packed in laminated plastic film bags (PE/PVDC/CPP, <TEX>$12{\mu}m/15{\mu}m/50{\mu}m$</TEX>). Compared to non smoke-dried powdered oysters, the smoking and dipping in oyster sauce enhanced the flavor and prevented lipid oxidation of the smoke-dried powdered oyster product. Shelf-life tests indicated that the vacuum-packaging method preserved the quality of smoke-dried powdered oysters stored for 150 days at room temperature.

LOW TEMPERATURES, PLASTIC FILM , MATURITY STAGE AND SHELF LIFE OF GUAVA FRUITS

SUMMARY Mature-green and commercial harvest stage guava fruits were picked in a commercial orchard in Zitacuaro, Michoacan, Mexico. They were wrapped in polyethylene plastic film bags (PF), that had pores of 10 mm diameter pores, and stored at 5 and 10 °C during 6, 12 and 18 days. The results were compared with a control stored at temperate room (20 °C and 70% relative humidity). CO 2 , O 2 , and ethylene were determined in the internal atmosphere generated by the PF; the characteristics evaluated were weight loss, firmness, total soluble solids, titratable acidity and fruit color at the above mentioned storage days and 6 days after the removal of fruits from the cold storage. The PF modified the internal atmosphere in function of both temperature and stage of ripeness stage of the fruit. Fruit stored at 5 and 10 °C in PF had good physiological and biochemical characteristics, and good quality up to 18 days of storage. The best results were found with guavas harvested at the mature-green stage followed by 6 days after removal from storage at 5 °C for 6 days, chilling injury was not observed. The fruit stored at room temperature showed color and weight loss, and attack of Colletotrichum gloeosporioides Penz. after 18 days of storage.

Hygroscopic Coatings Control Surface White Discoloration of Peeled (Minimally Processed) Carrots During Storage

ABSTRACTWhite discoloration on peeled carrots is partially due to surface dehydration which can be controlled with hygroscopic coatings: e.g., polyhydric alcohols and salt solutions. This study was performed at 2.5, 7.5, 10, and 15°C, using a model system controlling relative humidity at 33, 75 or 98% or a commercial system with low‐density polyethylene (LDPE) plastic film bags. The moisture sorption properties of propylene glycol, sorbitol, glycerol and calcium chloride enabled them to keep the carrot surface moist and maintain a transparent surface layer through which the underlying orange color was visible. This effect was only observed at high relative humidities (e.g., 98% RH). Similar effects were observed on treated peeled carrots stored in LDPE bags. The moisturized appearance provided by the hygroscopic coatings during storage was effective at several different temperatures.

Mechanism of Surface White Discoloration of Peeled (Minimally Processed) Carrots During Storage

ABSTRACTA proposed mechanism of white discoloration development on peeled carrots included both physical and physiological responses to wounding. The physical response is a color change due to reversible surface dehydration. This study was performed at 2.5 and 10°C using a mode1 system controlling relative humidity, at 33, 75 or 98%, and a commercial system with low‐density polyethylene (LDPE) plastic film bags. The rate of surface discoloration increased with decreasing RH. When excess surface moisture was left on peeled carrots, rates of white development decreased sharply at all RH compared with a dewetted control. The same effects were observed on peeled carrots stored in LDPE bags. Carrots partially regained their original color when water‐dipped, due to reversal of the physical response component.

ウメ及びカボスの品質保持に及ぼすエチレン&amp;bull;アセトアルデヒド除去剤とフィルム密封包装の効果

A simple CA storage method using both ethylene-acetaldehyde (E•A) removing agent and seal-packaging with plastic film bags was applied to mature-green Japanese apricot (Mume)(Prunus mume Sieb. et Zucc.) and green Kabosu fruits (Citrus sphaerocarpa hort. ex Tanaka). The effects of each gas level in the sealpackaged bag (ethylene, acetaldehyde and carbon dioxide) on the keeping quality and physiological injury were examined by using the film properties as parameter.(1) Mature-green Mume could be stored at 20°C for more than 9 days by this method.(2) The physiological injury on mature-green Mume increased remarkably at a carbon dioxide level of about 20% and occured in almost all fruits at higher than 25%. Whereas in the presence of E•A removing agent, the physiological injury was suppressed remarkably and the ratio of injured fruits was 0-4% at a carbon dioxide level below 25%.(3) When green Kabosu fruits were stored at 5°C by this method, degreening and the physiological injury were not detected for more than 4 months.(4) The physiological injury on Kabosu fruits increased remarkably at an acetaldehyde concentration above 2ppm and rached 100% at 10ppm.(5) The level of carbon dioxide in seal-packaged bag had a significant influence on ethylene and acetaldehyde production, and it was determined by both the respiration of fruit and the gas permeability of film.

Leakage of gaseous 125I from a Na125I solution through a plastic film

Leakage of gaseous 125I from the various kinds of plastic film bags packing Na125I solution was determined. The polyethylene bag was permeable to the gaseous 125I and active charcoal could not prevent the leakage. The laminated plastic bags composed of polyethylene terephthalate and polyethylene was slightly permeable, and the leakage decreased either in the presence of active charcoal or with the use of doubly packed bags. Leakage of 125I from the various kinds of container for the Na125I solution was also determined.