• Advances in nano research
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• v.12 no.6
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• pp.629-638
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• 2022

This work shows the impregnation of scents using a graphene sponge (GS). This was functionalized by the modified Hummers method, pursuing to add different functional groups. It is proposed to achieve the release and seek to control it through electrical potential applied to the graphene sponge with essential oils. The graphene sponge was functionalized and steeped with two kinds of oil. The electrochemical study demonstrates the variation in the electrochemical behaviour of the functionalized graphene sponge without and impregnated with oil. The release of the oil and its aromatic scents was carried out by applying an electrical potential of 30 V, with a release rate of 1.86 mg/min. The heating of the sample that causes the release of oil, associated with the electrical resistance of the system, reaches temperatures of about 150℃. The essential oils, graphene sponge, surfactant, graphene sponge with essential oils, graphene sponge recuperated after applying electric potential, graphene sponge recovered by temperature and dipropylene glycol (DPG) were characterized using Fourier transformed infrared spectroscopy (FTIR), digital microscopy, and x-ray photoelectron spectroscopy (XPS).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.95-102
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• 2016

This study investigated the effects of the oxygen permeability of vacuum packaging film and the storage temperature on the quality and shelf life of Hamburg steaks during storage for 14 days. Control samples (C) were packaged in a polyamide/polyethylene (PA/PE) film and stored at $5^{\circ}C$. Treatment samples were either packaged in an ethylene vinyl alcohol/polyethylene (EVOH/PE) copolymer film and stored at $5^{\circ}C$ (T1), and in a PA/PE film and stored at $-18^{\circ}C$ (T2). The initial total plate count (TPC) was 3.6 log cfu/g. In T1 samples, TPC and Brochothrix thermosphacta counts were increased, similar to those in C samples, whereas Pseudomonas spp. counts were significantly lower than those in C samples during storage. Over the storage period, the volatile basic nitrogen values increased most rapidly in C samples, followed by T1 and then T2 samples. The values of thiobarbituric acid reactive substances steadily increased in all samples during storage. The colour parameters were not significantly different among the samples during storage. T1 samples maintained sensory qualities in flavour and off-odour parameters for two days longer than C samples did. At day 12, T2 samples were evaluated as being below the marketability score of 5.0 for texture. In conclusion, using high oxygen barrier films like EVOH/PE copolymer for packaging Hamburg steaks could extend the sensory qualities in view of flavour and off-odour during chilled storage. However, frozen storage at $-18^{\circ}C$ is recommended when the storage period is extended beyond 14 days at $5^{\circ}C$.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.39-51
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• 1994

When broiler litter was composted under the control of peak temperature of piles(uncontrolled, controled below $70^{\circ}C$ and below $60^{\circ}C$), changes of physical and chemical parameters were determined throughout the processing period. Broiler litter was composted in each of three $1.0{\times}1.0{\times}1.2m$ dimensional facilities for 8 weeks. After 5 to 6 weeks of composting, broiler litter was converted into the final compost with no ammonia odour, rice hull size of particle, and faint brown color. Central temperature of piles reached to the peak(about $69{\sim}70^{\circ}C$) within 3 to 4 days after composting and gradually decreased thereafter. The final product contained 26.5% of moisture, 9.0~9.1 of pH, and 14.0~14.3 of C/N ratio. The increase of C/N ratio with processing resulted from the considerable loss of N. The total wet weight of the final composts was an average of 38.3% of the initial weight, the dry weight of those 64.1%, and the organic matter weight of those 34.8%. Treatments of central temperature of composts did not affect changes of moisture, pH, C/N ratio, total wet weight, total dry weight, and total organic matter weight. In general, composted broiler litter was converted into the final product with little change in physical and chemical parameters after 5 to 6 weeks of processing. Nitrogen losses during the composting should be prevented for the improvement of the composting efficiency of broiler litter.

• Korean Journal of Food Science and Technology
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• v.2 no.1
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• pp.104-112
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• 1970

Korean Paldal variety rice, harvested November and hulled into polished and unpolished forms in April, 1969, packed in the straw bags and the kraft paper bags. Being irradiated with 10, 30 and 50 krad ${\gamma}-ray$, the samples were stored at room temperature for testing infestation, uric acid content, fat acidity, riboflavin content and panel test. The results are as follows. 1. The kraft bag lot with polished rice or unpolished rice manifested the apparent disinfestation with $30{\sim}50$ krad irradiation. On the other hand, in the straw bag lot the irradiation effects on disinfestation were weakened through summer on account of the second contamination. 2. The changes of uric acid content in rice were proportional to the state of infestation. 3. Fat acidity, which has a close relation with the rancidity of fat in rice, increased during storage and showed some increasing tendency in the irradiated lot with $30{\sim}50$ krad. 4. In comparison with the control lot, riboflavin content was not affected by 50 krad irradiation. 5. With 10, 30 and 50 krad dose, the irradiated lot should have no significant difference in taste, odour, color and viscosity for the panel test.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.134-138
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• 2015

BACKGROUND: In recent years, several researchers have focused on odour control methods to remove the harmful chemicals from chemical accidents and incidents. The present work deals with the system development of the hazardous. METHODS AND RESULTS: For on-site removal of hazardous gaseous materials from chemical accidents, mobile vortex wet scrubber was designed with water vortex process to absorb the gas into the water. The efficiency of the mobile vortex wet scrubber was evaluated using water spray and 25% ammonia solution. The inlet air velocity (gas flow rate) was according to the damper angle installed within the hood and with increase of gas flow rate, consequently the absorption efficiency was markedly decreased. In particular, when 25% ammonia solution was exposed to the hood inlet for 30 min, the water pH within the scrubber was changed from 7 to 12. Interestingly, although the removal efficiency of ammonia gas exhibited approximately 80% for 5 min, its efficiency in 10 min showed the greatest decrease with 18%. Therefore, our results suggest that the ammonia gas may be absorbed with the driving force of scrubbing water in water vortex process of this scrubber. CONCLUSION: When chemical accidents are occurred, the designed compact scrubber may be utilized as effective tool regarding removal of ammonia gas and other volatile organic compounds in the scene of an accident.

• Korean Journal of Poultry Science
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• v.13 no.1
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• pp.41-48
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• 1986

In order to investigate the storage period of packed chicken meat in relation to the bacterial contamination of each processing part, a special grade poultry processing plant located at Dongdoochun-City, Gyeonggi-Do, was surveyed mainly in point of sanitary conditions. The results are summarized as follows. 1. processing room near reception and packing room next to shipping area showed the highest bacterial counts in air. 2. Equipments and instruments for slaughtering also showed a high degree of bacterial contamination even before the operation. This finding suggested that the possibility of the bacterial contamination of carcasses through equipments and instruments would be high, if the continuous sanitary control measures are not properly taken. 3. The bacterial count of scalding water was 3${\times}$10$\^$7/ for standard plate count and 4${\times}$10$\^$5/ for most probable number of coliform bacteria at 1 hour after the start of operation. These values were maintained until the completion of processing. 4. At the ending of chilling process, the bacterial counts of chilling water were 3.3 ${\times}$10$^4$ and 3.0${\times}$10$^3$for standard plate count, when the volume of water used per bird were 21 and 51, respectively. Bacterial contamination was further decreased about 10$\^$-3/-10$\^$-4/ times as the effective chlorine concentration in chilling water was maintained about 50 ppm. 5. An average standard plate count of the residual water In abdominal cavity of carcasses was 3.9${\times}$10$^4$immediate after chilling, however, it increased to 4.7${\times}$10$\^$7/ when the carcasses were packed and stored for 10 days at 4$^{\circ}C$. off-odour development was observed as the bacterial count was not less than 10$\^$6//$m\ell$ of the residual water of the packed carcasses. Data indicated that if the standard plate count of the residual water in abdominal cavity of carcasses was not less than l0$^4$immediate after chilling, the packed chicken meat would not be stored longer than 5 days at 4$^{\circ}C$.