• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.245-250
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• 1977

Experiment were conducted to find out the effective drying method of citrus peel produced in Korea by varying the temperature of hot air, surface area of peels, peels from several citrus varieties and physicochemical treatment of the peel. 1. About $3{\sim}6\;days$ were required to reduce the moisture level of the peel from 70%(wet basis) to 20% at room temperature without forced convection. 2. Drying was speeded up until the temperature of hot air reached $60^{\circ}C$. Beyond that no significant increase in drying rate was observed. About 50 minutes were needed to reduce the moisture level (dry basis) to below 10% at $60^{\circ}C$ by forced convection 3. When the peel surface area was increased twice by cutting the peel into 256 fractions, the overall drying time (the time required to reduce the moisture level to 10%, dry basis) was shortened to 15 minutes from 50 mintes of the original peel. 4. No significant difference in drying rate was observed among the peels from several citrus varieties except Shaddock jabon and Citrus ponki tanaka, which dried more slowly than others. 5. Treatment of $Ca(OH)_2$ and the pressing of the peel before drying were effective in drying only when the initial moisture content was substantially higher.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.647-652
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• 2018

Extracts from bay leaves, Chongbaek (Allium fistulosum L.), Hutgae (Hovenia dulcis Thunb.) fruit, and green tea, using Soju (Korean alcohol, $30^{\circ}$) as a solvent were analyzed for their antioxidative properties. The eels were evenly coated with the extract concentration equivalent to 2% of their total weight and dried for 15 hours at $35^{\circ}C$ using an air blower. The DPPH radical scavenging effect, acid value and peroxide value of semi-dried eel, and linoleic acid peroxidation of eel oil were investigated. The highest level of DPPH radical scavenging was found in green tea extracts, followed by Hutgae fruit extract and bay leaves extract (p<0.05). The acid value and peroxide value of Hutgae fruit extracts coated eels refrigerated for 21 days were the lowest followed by the green tea extract coated eels. During the 20 days reaction period, all four kinds of extracts analyzed were found to effectively decrease linoleic acid peroxidation. Among them, Hutgae fruit and green tea extracts decreased the peroxide content of eel oil steadily and for a longer period when compared to other extracts. In conclusion, pre-application of Hutgae fruit and green tea extracts on eels before drying was found to be effective in delaying peroxidation in eels during the drying process and refrigeration.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.818-823
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• 2002

Effects of pelleting, drying, conditioning, and additives on the characteristics of Yukwa (fried pellet) were determined. RVA maximum paste viscosity of Bandegi (waxy rice pellet) was the highest after 2 days of moisture conditioning process, and decreased 2 days later. Air bubbles in Bandegi were distributed uniformly but were not significantly affected by conditioning time. For higher expansion and softer texture of Yukwa, the optimum moisture content of dried and conditioned Bandegi was $14{\sim}17%$. The addition of soymilk and 25% alcohol (Soju) as additives was also effective for achieving higher expansion and soft texture of Yukwa, respectively. Larger air cells were distributed in the center and smaller ones on the edge of Yukwa.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.27-32
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• 2002

We investigated the effect of polyethylene glycol(PEG) treatment of preservative treated green japanese cedar(Cryptomeria japonica) round posts on their preservative penetration and check formation during the air drying. The round rods were dip-treated in 10% preservative solution of Basilit CFK for 1 day, followed by application(3, 5, and 10 times) with 50% PEG-400 solution, and then dried for 30 days under natural conditions. The rate of preservative penetration into sapwood was a low by 23.2% without PEG treatment, whereas that was a high by about 51.2~64.5% with PEG treatment. From these results, it was assumed that PEG played an affirmative role in the penetration of preservative components loaded onto the surface of round rods by dipping. During the air drying, the formation of drying checks decreased significantly with increasing application times of PEG. Even though some drying checks in PEG treated rods were developed, the number and size of checks was reduced remarkably by PEG treatment. After 2 months of outdoor exposure, PEG treatment failed to reduce checking in preservative-treated rods whereas finishing of polyurethane resin lacquer after PEG treatment was significantly effective in preventing check development.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.23-26
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• 2003

This study is intended to investigate the properties of early strength development by application of TEA to the field. According to the results, when TEA is added, fluidity is almost same to base concrete, and increases upto aimed slump after field flowing. Setting time does not differ in the case of base and TEA, but retarded after flowing. The time when compressive strength gains 5 MPa, which side form can be removed, is 23 hours, and so the removal time is shortened by I hours in comparison with plain concrete. But compressive strength is almost same to that of plain concrete at 28 days. The rebound value of P type schmidt hammer show similar tendency to compressive strength, and the rebound value of structure is higher than that of standard curing specimen due to heat capacity effect and drying by the air outside. Therefore, it is thought that if the rebound value of P type schmidt hammer is controled. by about 26 in consideration of open air environment, it is very effective to determine the removal time of side forms.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.23.1-26
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• 2003

This study is intended to investigate the properties of early strength development by application of TEA to the field. According to the results, when TEA is added, fluidity is almost same to base concrete, and increases upto aimed slump after field flowing. Setting time does not differ in the case of base and TEA, but is retarded after flowing. The time when compressive strength gains 5 MPa, which side form can be removed, is 23 hours, and so the removal time is shortened by 1hours in comparison with plain concrete. But compressive strength is almost same to that of plain concrete at 28 days. The rebound value of P type schmidt hammer show similar tendency to compressive strength, and the rebound value of structure is higher than that of standard curing specimen due to heat capacity effect and drying by the air outside. Therefore, it is thought that if the rebound value of P type schmidt hammer is controled. by about 26 in consideration of open air environment, it is very effective to determine the removal time of side forms.

• Journal of Applied Biological Chemistry
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• v.55 no.2
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• pp.123-127
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• 2012

In order to develop eco-friendly biopesticide, an entomopathogenic bacterium Photorhabdus temperata M1021 has been lyophilized via freeze-drying along with protective agents such as skim milk, starch, sodium alginate, glucose and sodium glutamate to protect cells from lysis. Freeze-drying powder of P. temperata M1021 containing 7% skim milk (w/v) showed highest survival rate of 63% among all the protective agents used in trials. Furthermore, the freeze-dried microbial powder showed 75% of survival rate after stored at $4^{\circ}C$ for 4 weeks at air contact conditions. Injection toxicity of the freeze-dried sample was tested against larvae of Galleria mellonella. A dose of $2.0{\times}10^1$ cells of P. temperata M1021 killed 100% of the G. mellonella larvae within 4 days after injection. Moreover, $2.0{\times}10^0$ cells caused 50% mortality within the 4 days after injection. Freeze-dried P. temperata M1021 strains exhibited effective insecticidal activity and could be a better candidate for being used as a biopesticide.

• Food Science and Preservation
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• v.21 no.5
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• pp.652-660
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• 2014

To maintain the microbiological safety of Prunus mume fruit before it is processed, it was treated with a combination of 0.5% citric acid and 0.1% Tween 20, and stored at $4{\pm}1^{\circ}C$ for seven days. The combined treatment reduced total aerobic bacteria, yeast, and mold populations in the fruit by 2.20 and 1.70 log CFU/g, respectively, compared to those in the control. Organic acid contents and the Hunter $L^*$, $a^*$, and $b^*$ values were not affected by the treatment during the storage. In addition, the dried Prunus mume fruit prepared with 40% red algae extract (RAE) or maltodextrin (MD) treatment and hot-air drying were compared with respect to the fruit's physicochemical properties such as color, total phenolic and flavonoid content, and microstructure. The hot-air dried samples had undesirable color changes and inferior textures. The RAE-treated samples had a higher total phenolic content (225.15 mg gallic acid equivalent (GAE)/100 g) and total flavonoid content (49.25 mg quercetin equivalent (QE)/100 g) than the other treatments. The treatment of Prunus mume fruit with RAE can provide better-dried products than can MD treatment or hot-air drying. These results suggest that the combined treatment with citric acid and Tween 20 can be effective in preserving the microbiological safety of Prunus mume fruit, and its dehydration using RAE is an efficient drying method.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.217-223
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• 1988

For the Effective utilization of the fish resources in coastal regions, investigations on preparation of powdered dried arkshell instant soup., quality stability of the products during storage and utilization as a food material were carried out with arkshell, Anadara broughtonii. Three kinds of powdered instant soup were prespared as 0% table salt(A), 5% table salt (B), 15% table salt(C) and packed with vacuum in laminated film bag. (polyester/nylon: 85${mu}ell$/15${mu}ell$, 18$\times$27cm) Their processing conditions and quality stability during storage at room temperature for 90 days were examined. Powdered instant soup was made by washing raw arkshell to remove visceral, clay, sand and blood, hot air drying(60$\pm$1$^{\circ}C$, 20 hrs) after draining and pulverizing dried arkshell to 35 mesh. Powdered instant soup was made by adding 2% sugar 0% table salt (5% and 15% table salt), 10.5% monosodium glutamate, 0.3% black pepper and 0.3% garlic powder to the pulverized dried arkshell. The condition of moisture and water activity of the products were 5.9-6.9% and 0.42-0.43, respectively. The moisture content s , water activity and pH of the products were showed little change and volatile basic nitrogen of them increased slightly during storage. Thiobarbituric acid value increased up to 60 days of storage and then decreased slightly. In solubility, powdered instant soup were showed no remarkable difference comparing with goods on the market. The color value of th products were showed little change during storage, In sensory evaluation, product B were scored slightly higher, in most cased, in flaver, color. taste and overall acceptability comparing with product A or product C during storage. Judiging form the sensory evaluation, powdered instant soup of 5% table salt (B) were the most desirable, and the quality of the products was stable for 90 days at 20$\pm$3$^{\circ}C$.

• Journal of Forest and Environmental Science
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• v.36 no.4
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• pp.267-273
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• 2020

Diospyros mespiliformis is a highly valued and threatened tree species within the Sahelo-Sudanian zone of Africa, but its seed germination requirements under cultivation are not well researched. In a first experiment which aimed at determining germination response of seeds to dehydration, fresh seeds were dried at room temperature for 26 days during which their moisture content, their germinability, and their viability were monitored at two-day intervals. In the second experiment, 14 pre-germination treatments were tested for their effect on the germination of dried seeds. Results showed that fresh seeds had 52.7% moisture and achieved 97.7% germination. As seeds were dried, percentage germination gradually decreased with decreasing moisture content and reached 0% when moisture content had dropped to 18%. Meanwhile, seed viability remained at 100% over drying duration. Seeds that were not germinated after air dry also recorded 100% viability. The most effective treatment for inducing germination of dried seeds was scarification using 98% sulfuric acid for 30 min which resulted in 96.6% germination. This study reports for the first time in D. mespiliformis seeds a desiccation-induced dormancy which can be efficiently alleviated by acid scarification. This study provides useful information that will contribute to efficient management of D. mespiliformis seed resources for propagation.