• Food Science and Preservation
• /
• v.24 no.3
• /
• pp.483-489
• /
• 2017

Phloridzin is a predominant member of the chemical class of dihydrochalcones and mainly found in apple. The biological activity of phloridzin treated with dielectric barrier discharge (DBD) plasma was evaluated to investigate whether exposure to plasma can be used as a tools to enhance the biological activity of natural resources. DBD plasma treatment of phloridzin was carried out for three different exposure times. The antioxidant effects of degraded phloridzin for different reaction time were evaluated via radical scavenging assay using DPPH radical. In addition, the anti-diabetic and anti-obesity properties of the degraded phloridzin were measured based on ${\alpha}$-glucosidase and pancreatic lipase inhibitory activities. Phloridzin treated for 60 min showed significantly higher radical scavenging, ${\alpha}$-glucosidase and pancreatic lipase inhibitory activities compared to the tested positive controls. Degradation of phloridizin induced by DBD plasma might be responsible for enhancing the biological activity of phloridizin.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.30 no.2
• /
• pp.107-120
• /
• 2024

This study compared the production systems and packaging methods as pre- and post-harvest factors for Korean head cabbage, which is minimally processed at the industry locus. It examined how different crop production systems, specifically winter and spring cultivations, affect the characteristics of the Korean head cabbage after harvest. The quality of changes in cabbage characteristics was evaluated over 4 weeks at 10℃. After harvesting, soluble solids content (SSC), hardness, and DPPH (2,2-diphenyl-1-picrylhydrazyl) levels exhibited variations depending on the crop production system, with winter kimchi cabbage maintaining higher levels. These attributes were also influenced by the crop systems and packaging methods. Significant differences were observed in the changes in fresh weight of the Korean head cabbage depending on the packaging method; the extent of these changes was reduced with polypropylene (PP) film packaging. Although the freshness of Korean head cabbage decreased during storage, the appearance was somewhat preserved through film packaging after harvest. The results indicated that the properties of stored Korean head cabbages experienced different effects on pre- and post-harvest quality and characteristics, depending on the measurement items.

• The Korean Journal of Pesticide Science
• /
• v.19 no.3
• /
• pp.295-300
• /
• 2015

Currently, amount of export strawberry has been continuously increased to ship many south Asia countries, including Hong Kong and Singapore. In the distribution process, significant damage to the quality has been caused depending on the environmental conditions. Gray mold disease caused by Botrytis cinerea has been known as major damage to the export strawberry, and the disease was caused during shipping and distribution to the final consumers. This study was performed to assess the relationship between pathogen density in packing shed and disease incidence of gray mold during storage period. Maximum gray mold disease incidence in storage period was up to 16% with low temperature condition ($4^{\circ}C$). At room temperature condition, the disease incidence reached up to 100% even densities of the pathogen spore were recorded relatively low in the packing shed. As results of the study, the correlation between pathogen density in the air and disease occurrence clearly clarified.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2004.04a
• /
• pp.192-210
• /
• 2004

Application methods of chemicals were investigated tn minimize strength reduction of corrugated boards under the high humidity environment encountered in the cold chain system. Starch insolubilizers were introduced in the starch solution preparation of the Stain hall method and their insolubilization effect of starch binder were estimated. The performance of water repellent agents(WRA) and moisture proof agents(MPA) were evaluated in terms of water and moisture resistance. And effects of the combination of the chemicals and the coating method were also examined. Addition of the polyamine polyamide insolubilizer to the main part in the Stain hall process improved the binding force and water resistance of starch, which contributed to minimize the strength reduction of paper under the high humidity environment. AZC and Glyoxal type insolubilizers could not be used in the experiment due to an excessively increased viscosity of starch solution and the poor stability. Conventional WRA treatment to the base paper enhanced water and moisture resistance very slightly even though water repellency of the paper reached R10 by the treatment. MPA showed excellent performance than WRA not only in water and moisture resistance but in water repellency. Double coating on paper with MPA was more effective than the single coating at the same coating weight. A newly developed MPA showed excellent performance and runnability only by a single coating instead of a double coating.

• Journal of Bio-Environment Control
• /
• v.16 no.3
• /
• pp.247-251
• /
• 2007

To extend the shelf-life of spinach after harvest, we investigated the effect of various packaging methods and storage temperature. In case of polypropylene film package, there was no weight loss, but in non-package, remarkably weight loss occurred as storage period extended and storage temperature risen. Content of vitamin C was decreased rapidly at early stage of storage, and decrease of vitamin C in low temperature storage was lower than that of room temperature storage, but its large difference according to packaging method was not observed. In hunter's value on spinach, b value in room temperature storage was higher than that of low temperature storage. In terms of freshness, shelf-life of spinach by low temperature storage $(1{\sim}3^{\circ}C)$ after PP film packaging lasted 34 days, and that by room temperature storage $(10{\sim}15^{\circ}C)$ after PP film packaging lasted 8 days, but that by room temperature storage after non-packaging lasted 3 days.

• Korean Chemical Engineering Research
• /
• v.47 no.2
• /
• pp.237-242
• /
• 2009

Various type of alternative fuel have been developed due to exhaustion of fossil fuel reserves and high oil price. Biodiesel is produced from the reaction of triglyceride, which is main component of animal fat and vegetable oil, and methanol by methanolysis as it is known for eco- friendly fuel for alternative petrodiesel. In this work, it was analyzed for the characteristics of the blended biodiesel with domestic petrodiesel according to blending ratio. Density, kinematic viscosity and flash point were increased with increasing the content of biodiesel. But the characteristic of blended biodiesel fuel were changed to aggravate in low temperature. Also, the derived cetane number(DCN) from IQT was increased by added biodiesel. Especially, the DCN of biodiesel from palm oil showed 71.26.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.36 no.2
• /
• pp.60-69
• /
• 2004

Application methods of chemicals were investigated to minimize strength reduction of corrugated boards under the high humidity environment encountered in the cold chain system. Starch insolubilizers were introduced in the starch solution preparation of the Stein hall method and their insolubilization effect of starch binder were estimated. The performance of water repellent agents(WRA) and moisture proof agents(MPA) were evaluated in terms of water and moisture resistance. And effects of the combination of the chemicals and the coating method were also examined. Addition of the polyamine polyamide insolubilizer to the main part in the Stein hall process improved the binding force and water resistance of starch, which contributed to minimize the strength reduction of paper under the high humidity environment. AZC and Glyoxal type insolubilizers could not be used in the experiment due to an excessively increased viscosity of starch solution and the poor stability. Conventional WRA treatment to the base paper enhanced water and moisture resistance very slightly even though water repellency of the paper reached R10 by the treatment. MPA showed excellent performance than WRA not only in water and moisture resistance but in water repellency. Double coating on paper with MPA was more effective than the single coating at the same coating weight. A newly developed MPA showed excellent performance and runnability only by a single coating instead of a double coating.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.4
• /
• pp.429-434
• /
• 2014

Purpose: To analyze thermal effect on mechanical properties of domestic commercial polymer-based eyewear frames. Methods: In this study, materials of cellulose acetate, polyamide, epoxy, and polyetherimide were exposed to high or low temperature and were mounted on universal test machine (TO-100-IC) for tensile strength test. Elastic behavior, Young's modulus, maximum displacement, and fatigue were tested with various temperature ($-25^{\circ}C$, $25^{\circ}C$, $60^{\circ}C$). Results: As a result, at room temperature, displacements of materials were changed with increasing impact load. At low temperature ($-25^{\circ}C$), maximum displacements of all specimens were decreased but young's modulus were increased. However, at high temperature, maximum displacements of all specimens were increased but young's modulus were decreased. Conclusions: Degree of displacements due to fatigue behavior was increased following direction of PEI, epoxy, polyamide, acetate. We concluded that commercial polymers used in eyewear frames physical properties were changed differently to exposed temperature.

• Korean Journal of Agricultural Science
• /
• v.29 no.1
• /
• pp.24-31
• /
• 2002

This experiment was conducted to improve the market quality of fresh strawberries through postharvest treatment of $CO_2$ at commercial level. Postharvest application of $CO_2$ increased flesh firmness regardless of ripeness of strawberries. Firmness further increased in berries of full maturity but the actual firmness was higher in less mature berries. The optimal condition of $CO_2$ treatment was above 15% of $CO_2$ for 4 hours during cooling of harvested fruit. Residual effect of firmness increase was remained until simulated shipment as well as retail condition for 1 days at ambient temperature. Market quality of full ripe fruit at harvest significantly reduced due turning skin color to dark red and dryness of physically injured surface. Result indicated that a short term application of $CO_2$ during cooling has a benefit for keeping freshness of strawberries during export and local marketing.

• Korean Journal of Food Science and Technology
• /
• v.41 no.4
• /
• pp.452-457
• /
• 2009

In order to secure microbiological safety and quality of commercial vegetable sprouts, buckwheat seeds and sprouts were investigated for their microbiological flora and for the effect of chlorine treatment on quality. Microbiological analyses showed that major inherent bacteria including Enterobacter, Sphingomonas, and Klebsiella were found in commercial buckwheat sprouts with a population size ranging from $10^5$ to $10^7$ CFU/g. In addition, buckwheat seeds had a similar microbial flora to sprouts. Foodborne pathogenic bacteria such as Escherichia coli O157:H7, Staphylococcus aureus, Salmonella Typhimurium, and Listeria monocytogenes were not detected in the sprout or in the seed samples. Chlorine treatment with 50-150 ppm sodium hypochlorite noticeably reduced viable bacteria cell counts of the sprouts by about 1 log. However, no significant difference was observed among the different chlorine concentrations. After storage for 7 days at $5^{\circ}C$, the sprouts treated with 100-150 ppm chlorine showed higher sensory scores in visual quality than the others (p<0.05). The results indicated that proper pretreatment, such as dipping in chlorinated water, could confer a beneficial effect on the microbiological safety and visual quality of buckwheat sprouts.