• Food Science and Preservation
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• v.7 no.1
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• pp.33-37
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• 2000

Effects on keeping quality according to the different package environment in cabbage and brccoli were studied. Opened 2 mil LDPE (low density polyethylene) sealed 4 mil LDPE and BA(barrier polyethylene) were used as package films. Weight loss was markedly in opened 2 mil LDPE in cabbage and broccoli as 6 and 28%, respectively. Carbon dioxide was higher in seal-packaging cabbage and broccoli with BA held at 4 $^{\circ}C$ was above 15 and 31% within 15 days, respectively, while oxygen content was depleted to 2% or less after 10 days. The main difference between volatile sulfur-containing compounds produced from cabbage and broccoli were the relative quantities and rates of production of hydrogen sulfide, carbonyl sulfide, methanethiol and dimethyl disulfide in opened 2 mil LDPE , sealed 4 mil LDPE and barrier bags during storage.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.203-209
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• 2023

The increasing saturation challenges in storage facilities for Low- and Intermediate-Level Radioactive Waste call for a more efficient storage approach. Consequently, we have developed a square-structured container that features a storage capacity approximately 20% greater than that of conventional drum-type containers. Considering the need to contain various radioactive wastes from nuclear power usage securely until they no longer pose a threat to human health or the environment, this study focuses on evaluating the sealing efficacy of the newly designed rectangular container using finite element analysis. Since radioactive waste containers typically do not experience external forces except under special circumstances, our analysis simulated the impact of an external force, assuming a fall scenario. After fastening the bolts, we examined the vertical stress distribution on the container by applying the calculated external force. The analysis confirms the container's stable seal.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.184-192
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• 2014

Various types of unit packaging methods were applied for 'Fuji' apples during short-term cold storage and export simulation. Gas tightness of the package was controlled stepwise in the successive two-year experiments using different perforation treatments (none, punch hole, or pinhole) and sealing methods (tie v s. heat seal). Risk of tight packaging and effectiveness of macroperforation on weight loss and quality maintenance were analyzed as related to changes in gas concentration inside the packages. Immediately after harvest, each 5 apple units were packaged in $40{\mu}m$ polypropylene (PP) film bags, stored 4 weeks at $0^{\circ}C$, and then put on the shelf for one week at ambient temperature in the preliminary experiment, In the main experiment, export process was imposed after storage simulating 2 week refrigerated container shipment at $0^{\circ}C$ plus one week local marketing at ambient temperature. Non-perforated film packaging with relatively high gas tightness induced flesh browning caused by carbon dioxide accumulation regardless of the sealing methods. Among perforated film packaging, in contrast, atmospheric modification was partly established only in the pinhole treatment and flesh browning symptom was not observed in all the treatments. Even the punch hole perforated film packaging without gas tightness effectively reduced the weight loss, whereas had slight benefits for quality maintenance. Reduced perforation using pinhole treatment seemed to improve sensory texture, while effects on physicochemical quality were insignificant. Overall results suggest the need of more minute perforation treatments on the packaging film to ensure modified atmosphere effects on quality maintenance.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.09a
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• pp.211-219
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• 2004

A new alloy definition will be presented concerning increasing demands for the board level reliability of miniaturized interconnections. The damage mechanism for LFBGA components on different board finishes is not quite understood. Further demands from mobile phones are the drop test, characterizing interface performance of different package constructions in relation to decreased pad constructions and therefore interfaces. The paper discusses the characterization of interfaces based on SnPb, SnPbXYZ, SnAgCu and SnAgCuInNd ball materials and SnAgCuInNd as solder paste, the stability after accelerated tests and the description of modified interfaces stric시y related to the assembly conditions, dissolution behavior of finishes on board side and the influence of intermetallic formation. The type of intermetallic as well as the quantity of intermetallics are observed, primaliry the hardness, E modules describing the ability of strain/stress compensation. First results of board level reliability are presented after TCT-40/+150. Improvement steps from the ball formulation will be discussed in conjunction to the implementation of lead free materials. In order to optimize ball materials for area array devices accelareted aging conditions like TCTs were used to analyze the board level reliability of different ball materials for BGA, LFBGA, CSP, Flip Chip. The paper outlines lead-free ball analysis in comparison to conventional solder balls for BGA and chip size packages. The important points of interest are the description of processability related to existing ball attach procedures, requirements of interconnection properties and the knowledge gained the board level reliability. Both are the primary acceptance criteria for implementation. Knowledge about melting characteristic, surface tension depend on temperature and organic vehicles, wetting behavior, electrical conductivity, thermal conductivity, specific heat, mechanical strength, creep and relaxation properties, interactions to preferred finishes (minor impurities), intermetallic growth, content of IMC, brittleness depend on solved elements/IMC, fatigue resistance, damage mechanism, affinity against oxygen, reduction potential, decontamination efforts, endo-/exothermic reactions, diffusion properties related to finishes or bare materials, isothermal fatigue, thermo-cyclic fatigue, corrosion properties, lifetime prediction based on board level results, compatibility with rework/repair solders, rework temperatures of modified solders (Impurities, change in the melting point or range), compatibility to components and laminates.

• 한국유가공학회:학술대회논문집
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• 2002.04a
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• pp.59-60
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• 2002

Edible films such as wax coatings, sugar and chocolate covers, and sausage casings, have been used in food applications for years$^{(1)}$ However, interest in edible films and biodegradable polymers has been renewed due to concerns about the environment, a need to reduce the quantity of disposable packaging, and demand by the consumer for higher quality food products. Edible films can function as secondary packaging materials to enhance food quality and reduce the amount of traditional packaging needed. For example, edible films can serve to enhance food quality by acting as moisture and gas barriers, thus, providing protection to a food product after the primary packaging is opened. Edible films are not meant to replace synthetic packaging materials; instead, they provide the potential as food packagings where traditional synthetic or biodegradable plastics cannot function. For instance, edible films can be used as convenient soluble pouches containing single-servings for products such as instant noodles and soup/seasoning combination. In the food industry, they can be used as ingredient delivery systems for delivering pre-measured ingredients during processing. Edible films also can provide the food processors with a variety of new opportunities for product development and processing. Depends on materials of edible films, they also can be sources of nutritional supplements. Especially, whey proteins have excellent amino acid balance while some edible films resources lack adequate amount of certain amino acids, for example, soy protein is low in methionine and wheat flour is low in lysine$^{(2)}$. Whey proteins have a surplus of the essential amino acid lysine, threonine, methionine and isoleucine. Thus, the idea of using whey protein-based films to individually pack cereal products, which often deficient in these amino acids, become very attractive$^{(3)}$. Whey is a by-product of cheese manufacturing and much of annual production is not utilized$^{(4)}$. Development of edible films from whey protein is one of the ways to recover whey from dairy industry waste. Whey proteins as raw materials of film production can be obtained at inexpensive cost. I hypothesize that it is possible to make whey protein-based edible films with improved moisture barrier properties without significantly altering other properties by producing whey protein/lipid emulsion films and these films will be suitable far food applications. The fellowing are the specific otjectives of this research: 1. Develop whey protein/lipid emulsion edible films and determine their microstructures, barrier (moisture and oxygen) and mechanical (tensile strength and elongation) properties. 2. Study the nature of interactions involved in the formation and stability of the films. 3. Investigate thermal properties, heat sealability, and sealing properties of the films. 4. Demonstrate suitability of their application in foods as packaging materials. Methodologies were developed to produce edible films from whey protein isolate (WPI) and concentrate (WPC), and film-forming procedure was optimized. Lipids, butter fat (BF) and candelilla wax (CW), were added into film-forming solutions to produce whey protein/lipid emulsion edible films. Significant reduction in water vapor and oxygen permeabilities of the films could be achieved upon addition of BF and CW. Mechanical properties were also influenced by the lipid type. Microstructures of the films accounted for the differences in their barrier and mechanical properties. Studies with bond-dissociating agents indicated that disulfide and hydrogen bonds, cooperatively, were the primary forces involved in the formation and stability of whey protein/lipid emulsion films. Contribution of hydrophobic interactions was secondary. Thermal properties of the films were studied using differential scanning calorimetry, and the results were used to optimize heat-sealing conditions for the films. Electron spectroscopy for chemical analysis (ESCA) was used to study the nature of the interfacial interaction of sealed films. All films were heat sealable and showed good seal strengths while the plasticizer type influenced optimum heat-sealing temperatures of the films, 130$^{\circ}$C for sorbitol-plasticized WPI films and 110$^{\circ}$C for glycerol-plasticized WPI films. ESCA spectra showed that the main interactions responsible for the heat-sealed joint of whey protein-based edible films were hydrogen bonds and covalent bonds involving C-0-H and N-C components. Finally, solubility in water, moisture contents, moisture sorption isotherms and sensory attributes (using a trained sensory panel) of the films were determined. Solubility was influenced primarily by the plasticizer in the films, and the higher the plasticizer content, the greater was the solubility of the films in water. Moisture contents of the films showed a strong relationship with moisture sorption isotherm properties of the films. Lower moisture content of the films resulted in lower equilibrium moisture contents at all aw levels. Sensory evaluation of the films revealed that no distinctive odor existed in WPI films. All films tested showed slight sweetness and adhesiveness. Films with lipids were scored as being opaque while films without lipids were scored to be clear. Whey protein/lipid emulsion edible films may be suitable for packaging of powder mix and should be suitable for packaging of non-hygroscopic foods$^{(5,6,7,8,)}$.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.321-328
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• 2011

Edible films were developed from jujube (Zizyphus jujube Miller) using depolymerization processes of ultrasound and high-pressure homogenization. A 4.6% (w/w) jujube hydrocolloid was treated by ultrasound (600W, 20 min) or homogenized at high pressure (172 MPa, 6 s) and mixed with whey protein isolate, glycerol, xanthan, and sucrose esters of fatty acids to form film-forming solutions from which films were formed by drying. The film prepared by highpressure homogenization (HPH film) produced more homogeneous films without particles than those prepared without depolymerization or with the ultrasound treatment. HPH films possessed the highest tensile strength (4.7MPa), the lowest water vapor permeability ($2.9g{\cdot}mm/kPa{\cdot}h{\cdot}m^2$), and the most uniform and dense microstructures among the films. Flavor profiles of jujube powder and the films were distinguishable. Heat seal strength and oxygen permeability of the HPH films were 44.4 N/m and $0.025mL{\cdot}{\mu}m/m^2$/day/Pa, respectively. Antioxidant activities of jujube power and HPH films were not significantly different.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.711-715
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• 2012

A laminate-composite film was developed using industry co-products of defatted mustard meal (DMM) and whey protein isolate (WPI). An individually prepared DMM-based film (DMM film) and a WPI-based film (WPI film) were thermally laminated at $130^{\circ}C$ at a rate of 30 cm/min. Microscopic images exhibited that the DMM film and the WPI film were continuously attached in the laminate without void spaces. The tensile strength, elongation at break, and water vapor permeability for the laminate were 0.7MPa, 4.0%, and $6.9g{\cdot}mm/kPa/h/m^2$, respectively. Stretchability and heat seal strength of the laminate were higher than those of the un-laminated DMM film. The film layers of the laminate were physically overlapped, not forming new biopolymer units induced by molecular interactions. The opportunity for DMM films to be used as food packaging materials for wrapping and sealing could be increased by thermal lamination with WPI films, which improves the stretchability and heat sealability of DMM films.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.51-58
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• 1999

The effects of glass composition on the wettability and reactivity with $ZrO_2$substrate was evaluated and fabrication variables and glass compositions was investigated. Various glass compositions was investigated. Alkaline earth silicate glass show good wettability and lower viscosity and crystallization of glass could be prevented by $B_2O_3$.The sealant glass begin to wet on $ZrO_2$substrate below $900^{\circ}C$ and porosity occurred in various glass compositions, the crystallization and porosity in the glass could be prevented by the addition of flux into glass composition. But flowability and reactivity of glass with $ZrO_2$substrate was enhanced. Processing variables should be optimized to reduce the porosity by enhancing the sintering of glass powder. Many silicate glasses were investigated for the applications of high temperature sealants. Wetting and bonding of glass was good enough to seal together between $ZrO_2$and other ceramic components of SOFC. But porosity and reaction layer were occurred in the sealant glass. It will be possible to produce glass sealant without porosity and reaction layer at the interface by optimization of processing variable and modify the glass compositions. In present study, wettability of glass-filler composite was investigated. The porosity, shape of filler and interfacial reactions of sealant glass with fillers were examined.

• Food Science and Preservation
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• v.9 no.3
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• pp.267-270
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• 2002

This study was carried out to establish storage methods and to keep high quality of the raw and boiled vegetable peanut. After boiling at 100$^{\circ}C$ for 20min at 7% saline water far 40min the pods were packaged with 80 $\mu\textrm{m}$ Ny/LDPE film in vacuum, 80$\mu\textrm{m}$ LDPE film and Gauge-bag, and stored at room temperature and 4$^{\circ}C$. The moisture content of pods in room temperature were decreased than pods at 4$^{\circ}C$. After 21days storaging with Gauge-bag, texture of pods were toughen because moisture content of pods reduced severely. Colour of raw pods in packaging 80 $\mu\textrm{m}$ Ny/LDPE film vacuum was severely browning but boiled pods was browning little after opening a seal. After 2days storage at room temperature and 21days storage at 4t, pods were deteriorated. The hardness was much lower in boiled kernels than raw kernels and decreased when the storage period elapsed.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.130-136
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• 1986

'Shingo' pears were seal-packaged in polyethylene (PE) film with different thickness of 0.04. 0.06, 0.07, and 0.08mm and stored for five months in an experimental storehouse with the temperature varyine 0 to $7^{\circ}C$ and relative humidity varying 86 to 89%. The atmosphere in PE film bags was modified to 5-l4% oxygen with 3-5% carbon dioxide depending on the film thickness and the storage period. Packaging of pears with PE film effectively reduced the weight loss, which resulted in good appearance after 5 months' storage, while non-packaged pears showed a slight wilt. Decay occurrence was not significantly different among the treatments. but role browning occurred a little more in packaged lots than in non-packaged lot. The sensory panel rated the pears front 0.07mm-thick bag highest in flavor, texture, and juiciness, which might be due to the high sugar content and low titratable acidity. The firmness of pear flesh decreased with the stogare time and its change was found to be highly correlated with that of cellulase activity (correlation coefficient= -0.946). Thisresult indicated that cellulase might be one of the enzymes responsible for the softening of pear fruit during storage.