• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.380-384
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• 1988

The coefficients of the hot-air and freeze dried garlic isotherms and the critical water activities of these were estimated to be 0.85-0.94 by the linear regression and 0.58-0.60 by the sensory evaluation and ${\Delta}E$ value. Water adsorption rate(K) of hot-air dried garlic packaged with $48{\mu}m$ low density polyethylene(LDPE) decreased from $0.12g\;H_2O/100g/day\;to\;0.093g\;H_2O$/100g/day with decreasing the package dimension from $0.051m^2\;to\;0.029m^2\;at\;40^{\circ}C$ and 75% RH, and that of freeze dried one decreased from $0.17g\;H_2O/100g/day\;to\;0.12g\;H_2O$/100g/day as the filling weight increased from 50g to 10g in the package of $0.051m^2$. Shelf-life of hot-air dried garlic packaged with $80{\mu}m$ LDPE were 99days at $40^{\circ}C,\;283day\;at\;30^{\circ}C\;and\;455\;days\;at\;15^{\circ}C$ in the 75% RH. The differences of water contents between predicted data with water vapor permeability of the conventional method and experimental data were 0-1.5% in the water content range of around 13-18%, but about 2 in the water content range of around 8-11%.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.2_3
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• pp.59-65
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• 2010

Starch was modified with epichlorohydrin(ECH) to improve the miscibility with LDPE and LLDPE. Native starch or epichlorohydrin treated starch was mixed with grycerol and LDPE/LLDPE resin using a kneader and extruded using a single screw extruder to make pallets. The pallets were compression-molded at 145 into composite boards to evaluate their color, oxygen permeation, mechanical and thermal properties, and degradability under UV irradiation. Sheets with epichlorohydrin treated starch generally showed higher L-value than that of native starch blend sheets. The hunter b-values in both native starch blends and epichlorohydrin treated starch blends increased with Increasing starch contents. Tensile strength and percent elongation of sheets decreased with increasing starch contents. Tensile strength and percent elongation of sheets decreased with increasing starch contents. The degradability of blends under UV radiation increased with increasing starch contents in both blend types. The results represents that crosslinking of starch with epichlorohydrin may be a good method to improve miscibility of starch with petroleum-based materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1767-1772
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• 2009

Brined Baechu cabbages were packed with different films of high density polyethylene (HDPE), aluminium polyethylene (Al/PE), nylon polyamide (Ny/PE), low density polyethylene (LDPE) and permeability-controlled polyethylene (Mirafresh (MF), US patent No. 5972815), and then stored at 4${^{\circ}C}$ for 4 weeks. Changes in quality characteristics of pH, acidity, total bacteria counts, lactic acid bacteria counts, E. coli counts, texture and $O_2$ concentration were determined during the storage. The pH of brined Baechu cabbage packed with Mirafresh (MF) film was 6.25 after 4 weeks from initial pH of 6.80. The acidity of all brined Baechu cabbages increased, however, the increase of the cabbage in MF was the lowest. The levels of total bacteria, lactic acid bacteria and E. coli in the cabbages packed with MF were also lower than the other films. After 4 weeks, of all brined springiness Baechu cabbages decreased, but MF showed relatively high springiness. The $O_2$ concentrations by its permeation through MF were 0.35%-1.00% at 4-25${^{\circ}C}$ after 1 week. In conclusion, MF was found to be the most effective packaging film for brined Baechu cabbage to extend shelf-life.

• Food Science and Preservation
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• v.10 no.2
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• pp.131-135
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• 2003

Bell pepper was packed with several plastic films, and investigated the quality Characteristics such as gas composition, weight loss, microbial load, soluble solid content, ascorbic acid and color during storage at 10$^{\circ}C$. Cast polypropylene (CPP), low density Polyethylene (LDPE), Polyolefin (MPD, PD961) and linear low density polyethylene (LLDPE) were used for this purpose. Oxygen concentration inside packages generally showed a 10∼14% after 1∼2 weeks, but package with CPP maintained above 15％ throughout the storage. Carbon dioxide concentration of CPP was above 2%, but other treatments showed below 2%. Weight loss of all treatments was below 3.0% after 5 weeks. Total microbial count showed a similar pattern compared to yeast and mold, and CPP maintained the highest microbial load after 3 weeks. Yellowness (b value) of bell pepper was generally increased throughout the storage, and MPD and PD961 were higher than other treatments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.1
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• pp.151-155
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• 2007

A comprehensive study to evaluate the relative antibrowning activity of 5 known natural juices was conducted. Among the juices tested, rhubarb juice showed the highest inhibitory activity on apple browning (${\Delta}L=0.47$ & ${\Delta}E=1.8$ after 6 storage days at $4^{\circ}C$). Even 50% diluted rhubarb juice was very effective in controlling apple discoloration, showing very limited change in Hunter's L and E values. No significant difference in apple slices browning was observed with respect to the packaging material (LDPE or nylon/PE). However, gas composition inside package was closely related to apple browning.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.461-467
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• 1998

Two hundred grams of fresh jujubes at whitish green maturity was packaged in the film bags of different gas permeabilities and stored at 0 and $5^{\circ}C$. Through the storage package atmosphere and jujube quality were monitored. Package of $30\;{\mu}m\;CPP$ film resulted in anaerobic conditions of $O_2$ content below 1% and $CO_2$ content above 15%, and caused off-flavor at both temperatures within 4 weeks. Package of $60\;{\mu}m\;LDPE$ film also showed potential risk of anaerobic condition development within 5 weeks, because of high $CO_2$ and/or low $O_2$ concentration at 0 and $5^{\circ}C$. Microperforated film packages could preserve quality of jujubes for 10 and 7 weeks at 0 and $5^{\circ}C$, respectively, which were significantly longer than shelf lives for perforated air pack and hermetically sealed packages.

• Food Science and Preservation
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• v.15 no.2
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• pp.185-190
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• 2008

We investigated changes in fruit quality of Hallabong tangor (Citrus Kiyomi ${\times}$ ponkan) that was packaged with Si+CaO and LDPE film. The flesh ratio during storage was 74.33% (${\pm}3.66$) to 81.56% (${\pm}1.38$). Firmness of M16A, a variant of Hallabong tangor, was higher 100g-force than that of Hallabong tangor, changes of firmness was not shown among film packages. A fruit juice was $12-14^{\circ}$Brix, and this increased somewhat at the end of storage without film packaging. The titratable acidity of the M16A variety was 0.2% lower than that of the Hallabong tangor. Hallabong and M16A maintained freshness and taste for 120 and 60 days, respectively. The level of reducing sugars in the Hallabong tangor was 1% higher than that of the M16A variety. Reducing sugars increased at room temperature storage without film packaging. Total sugar content was 9.19% (${\pm}2.03$) to 12.78% (${\pm}0.75$). The content of vitamin C declined slowly after 105 days of storage. In conclusion, storage of Hallabong tangor with film packaging coated with Si+CaO was effective for maintaining freshness and quality.

• Food Science and Preservation
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• v.22 no.5
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• pp.623-628
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• 2015

Fresh cut vegetables provide convenience and rapidity to consumers. However, they have a weakness with respect to their short shelf-life due to browning and quality degradation via increased respiration. To overcome this problem, the effect of packaging film on the short-term storage of cut kimchi cabbages was investigated. Polypropylene (PP), oriented polypropylene (OPP), and low-density polyethylene (LDPE) films were used as packaging film, and cut kimchi cabbages were stored in the packaging films at $5^{\circ}C$ for 4 weeks. PP film packaging showed the least weight loss and soluble solids loss after 4 weeks. Titratable acidity increased during storage for all samples, however, the increase rate of titratable acidity in PP and OPP film packaging decreased, which was lower than that of LDPE film packaging. Color values decreased over time during storage. In appearance, PP film packaging was better than other films due to their high transparency. In a sensory test, there was no statistical difference among samples. Taken together, the transparent PP film packaging was more effective for short-term storage of cut kimchi cabbages. Thus, this study provides useful information for the selection of packaging materials for cut kimchi cabbage marketing.

• Food Science and Preservation
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• v.6 no.4
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• pp.357-364
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• 1999

Modified atmosphere packaging(MAP) technology was applied to ‘Tsugaru’apple (Malus domestica Borkh) in order to extend the shelf-life of apples during distribution. ‘Tsugaru’apples were packed with the PE film of 40 $\mu\textrm{m}$ thickness(40LD), the PE film modified by the addition of 5% (w/w) zeolite (40CK), and the PE film bags containing the ethylene absorbent (40LP). Quality indices of ‘Tsugaru’apples during storage at 10$^{\circ}C$ were measured in terms of weight loss, soluble solids content, pH, titratable acidity, flesh firmness, peel color and sensory properties. Oxygen, carbon dioxide and ethylene concentration in the film bags changed rapidly at the early stage of storage. Weight loss of the control increased up to 3.0% after 60 days storage while those of the packed apples remained less than 0.6%. No significant differences in soluble solids content and titratable acidity could be found in all the treatments, but significant differences in pH between the control and the packed apples. Higher firmness was kept in 40LD and 40LD than other treatments during storage. Color of the peel changed rapidly in control but slowly in 40LD and 40LP. ‘Tsugaru’apples Packed with Packaging films showed a good visual and sensory quality. Results suggest that packaging treatment with LDPE of 40 $\mu\textrm{m}$ thickness and ethylene absorbent can be used for extending the shelf-life of ‘Tsugaru’apples during distribution.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.332-336
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• 2019

The use of ultraviolet (UV) spectroscopy for foods is known to have a microbial inhibitory effect. UV-A having a longer wavelength than UV-C can be used for continuous or intermittent UV irradiation of food stored in containers or packages. Because UV-LED can be used effectively at a low price, this study reported the effect of UV-A 365 nm-LED on inhibiting Bacillus subtilis in accordance with the packaging conditions employed in daily use. The packaging materials were linear low-density polyethylene (LLD-PE), nylon/low density polyethylene (LDPE), polystyrene, and glass. When all packaging materials were treated with 365 nm UV-LED, B. subtilis was observed to remain inactive for 30-60 min. Further, compared with the control (-log 5), the survival rate of B. subtilis was -log 2.0-2.5 for nylon/LDPE and -log 2.58-3.61 for LLD-PE. These packaging materials showed an excellent inhibitory effect regardless of their thickness. Typically, a decrease in the viable cell count of more than 3 log indicates a 99.9% bactericidal effect. These results suggest that 365 nm UV-LED permeated the packaging material and inhibited bacterial growth.