• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.30-36
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• 1983

Plywood, the representative interior decorative or structural material, is so inflammable that it may cause big fires. Therefore, it is required inevitably to manufacture the "Fire retardant treated plywood", and it will be a study on the redrying of treated plywood that we ought to solve. This study was carried out to investigate the absorption of 20% $(NH_4)_2HPO_4$ solution into the soaked plywoods by hot/cold soaking for 3/3, 6/3, 9/3 and 12/3 hours and to study drying process with drying curves and drying rates by press-drying at the platen temperature of 130, 145, 160 and $175^{\circ}C$. Solution absorption of plywoods in hot/cold soaking method increased steadily with the prolonged soaking time, and water absorption is higher than DAP absorption, and then chemical retention (DAP) exceeded the minimum retention [$1.125kg/(30cm)^3$] even in the shortest soaking treatment. Drying curves of water-soaked plywoods inclined more steeply than those of DAP soaked plywoods. And the drying proceeded rapidly with the increase in platen temperature and terminated in 2.5-4 minutes at the temperature of 160 and $170^{\circ}C$. Drying rate also increased generally with the increase of platen temperature. So it was at $175^{\circ}C$ in DAP-soaking and at $160^{\circ}C$ in water-soaking when the drying rate became above 10%/min.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.767-774
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• 2015

In recent decades, health concerns related to sodium intake have caused an increased demand for salt or sodium-reduced foods. Umami substance can enhance taste sensitivity to NaCl and may offer a unique approach to replace and reduce the sodium content in foods. In this study, hot water extraction conditions of Wando sea tangle with high umami taste were investigated. Wando sea tangle harvested in June was selected for hot water extraction based on its free amino acids composition. The quality properties of sea tangle extract were investigated at various extraction temperatures ($60^{\circ}C$, $80^{\circ}C$, and $100^{\circ}C$) and times (1 h, 2 h, and 3 h). Sea tangle extracts at the extraction temperature of $100^{\circ}C$ contained the highest soluble solids (35.47%~36.93%), and crude protein (3.75%~4.00%). Viscosities of sea tangle extracts decreased with increasing extraction temperature. Umami amino acids (glutamic acid and aspartic acid) and sensory characteristics were best at extraction conditions of $100^{\circ}C$ for 2 h. Saltiness enhancement of sea tangle extract powder was determined. Saltiness intensities of NaCl solution after adding 1% sea tangle extract powder were enhanced (1.84~4.25-fold). At the same saltiness intensity, sodium contents of NaCl solution with 1% sea tangle extract powder were 12.24~24.33% lower than that of NaCl solution. These results suggest that it is possible to reduce sodium in foods with sea tangle extract as a natural salt enhancer without lowering overall taste intensity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.761-766
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• 2015

This study investigated the effect of protease on quality characteristics of sponge cake. Protease was used at levels of 0.0005 U (PC-1), 0.0010 U (PC-2), 0.0015 U (PC-3), and 0.0020 U (PC-4) for sponge cake preparation. Amylogram showed the setback was significantly decreased in comparison with the control (P<0.05). Height and baking loss rate of control sponge cake were $4.24{\pm}0.18cm$ and $12.01{\pm}0.29%$, respectively. PC-3 and PC-4 showed increased heights of $5.22{\pm}0.16$ and $5.24{\pm}0.11cm$ as well as slightly increased baking loss rates of $12.71{\pm}0.31%$ and $12.89{\pm}0.61%$, respectively. Specific volume and color difference measurements of control showed a specific volume of $3.53{\pm}0.06mL/g$, crust color difference of $53.05{\pm}0.28$, and crumb color difference of $29.84{\pm}0.52$. Measurements of specific volume, crust color, and crumb color of PC-3 and PC-4 were $4.18{\pm}0.02mL/g$, $56.19{\pm}0.84$, $29.05{\pm}0.43$, $4.21{\pm}0.02mL/g$, $56.85{\pm}0.43$, and $29.45{\pm}0.47$, respectively. Firmness measurements showed that the control had the highest firmness. PC-3 and PC-4 were effective at improving the shelf-life of sponge cake as indicated by reduced firmness. Sensory evaluation results demonstrated that all samples scored higher than the control. Throughout the results, the addition of protease increased volume and improved quality characteristics of sponge cake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.687-694
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• 2015

The purpose of this study was to evaluate the yield, antioxidant content, and antioxidant activity of adzuki beans according to germination time. Cultivated varieties were Vigna angularis var. Nipponensis cv. Chungju-pat (CJP), and Yeonduchae (YDC), and Vigna radiata (L.) R. Wilczek cv. Dahyeon (DH). The moisture, crude protein, calcium, and magnesium contents of YDC significantly changed with increasing germination time, whereas potassium, natrium, and aluminium contents did not significantly change. Sprout yield, total polyphenol, flavonoid, and tannin contents of ethanolic extracts from adzuki and mung beans significantly increased with increasing germination time. Total polyphenol contents of ungerminated CJP, YDC, and DH were 1.96, 2.68, and 2.02 mg/g, and those of CJP and YDC germinated for 144 h were 3.33 and 3.47 mg/g, respectively. Total flavonoid content of adzuki beans substantially decreased with increasing germination time. Total tannin content substantially increased with increasing germination time, and YDC showed higher contents (0.85 mg/g) sample germinated for 120 h. DPPH radical scavenging activities of CJP and YDC substantially decreased with increasing germination time, whereas that of DH increased. ABTS radical scavenging activities of ungerminated CJP, YDC, and DH were 4.57, 6.51, and 2.82 mg/g, respectively, and increased after germination for 72~120 h.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1476-1483
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• 2015

This study was conducted in order to compare changes in the quality characteristics and antioxidant activity of mulberries depending on the degree of ripeness between greenhouse (GH) and open field (OF) cultivation. The mulberries were divided into five degrees of ripeness. Quality characteristics such as pH, acidity, antioxidant activity, and contents of free sugar, organic acid, polyphenols, flavonoids, and anthocyanins were investigated. pH level increased slightly while acidity decreased depending on the degree of ripeness. Fructose and glucose were detected in mulberries as the major free sugar. Fructose and glucose increased rapidly during ripening. Citric acid was major acid and decreased considerably during ripening. Contents of total polyphenols, flavonoids, and anthocyanins increased considerably in the last stage of ripening. Contents of polyphenols, and flavonoids in mulberry from OF were higher than from GH. DPPH and ABTS radical scavenging activities increased rapidly in mulberries of the last degree. Contents of functional components were not greatly different between GH and OF, whereas content of free sugar in GH was higher than that in OF.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.764-769
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• 1999

This study was designed to investigate the effects of sea tangle (Laminaria japonica) extract (Dasi-Ex group: dry base $4.0\%$) and fucoidan-added (Fuco-I, II, III group: fucoidan of $1,0\%,\;2.0\%,\;3.0\%$ added to Dasi-Ex) drinks on the formation of oxygen radicals and scavenger enzyme activities of stressed mice. ICR male mice (20 $\pm$2 g) were fed experimental diets and these drinks instead of water for 18 days including 4 days of sociopsychological stress. Dasi-Ex and Fuco-I, II and III groups resulted in a marked decreases $20\~40\%$ in basal oxygen radical (BOR) formation, and $15\~25\%$ in induced oxygen radical (IOR) formation compared with control group. Hydroxyl radical formations were significantly inhibited about $10\%$ in Dasi-Ex group, while remarkably inhibited $30\~40\%$ in Fuco-I, II and III groups. lipid peroxide (ISO) levels in Dasi-Ex group were not significantly different from those of control group, tut Fuco-I, II and III groups resulted in a significant decreases about $10\%$ in LPO levels compared with control group, Dasi-Ex, Fuco-I, II and III groups resulted in a marked decreases ($31\%,\;36\%,\;39\%$ and $42\%$, respectively) in oxidized protein levels through production of carbonyl group. Significant differences in nitric oxide (NO) levels in Dasi-Ex group were not obtained, but NO levels were slightly inhibited about $7\%$ in Fuco-I and II groups and $20\%$ in Fuco-III group compared with control group. Significant differences in superoxide dismutase (SOD) and catalase (CAT) activities in Dasi-Ex and Fuco-I groups were not obtained, but Fuco-II and III groups resulted in a significant increases $25\~40\%$ in SOD activities, and about $10\%$ in CAT activities compared with control group. These results suggest that the sociopsychological stress and aging process could be effectively inhibited by biological activity of sea tangle and fucoidan components.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.718-724
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• 1999

This study was investigated the changes of the properties of matter such as the gel formation of the combined fish based on the mixed rate between the ocean jumbo squid and Alaska pollock surimi, and compared the relationships between the gel formation and water holding capacity. The changes of the gel formation based on 20 min fish grinding time and $2.5\%$ salt concentration according to the mixed rate was thought as the optimal addition limit. There was no significant function of gel product more than $20\%$ Jumbo squid meat. The more squid meat in the mixed meat could make the lower breaking stress but 7:3 rate of pollock : squid could retain breaking strain. The effect of the moisture content on mixed fish meat was studied and the drastic decrease of the gel formation and water holding capacity was indicated in $78\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.42-45
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• 1999

Our previous studies have demonstrated the biological effects of alginic acid as a brown algae (Undaria pinnatifida) component on inhibitory action of obesity using animal model. Sprague-Dawely (SD) male rats were fed experimental diets ($10\%,\;20\%$ and $40\%$ brown algae noodle: BA-noodles) for 4 weeks. Effects of BA-noodles on triglyceride (TG), total cholesterol. LDL and HDL-cholesterol, and atherogenic ($10\%\~15\%$ and $15\%\~18%$, respectively) by administration of $10\%,\;20\%$and $40\%$ BA-noodles compared with control group. HDL-cholesterol contents in serum of SD rats for 4 weeks significantly increased in ranges of 7 to $16\%$ by administration of $10\%,\;20\%$ and $40\%$ BA-noodles compared with control group. Atherogenic index (AI) in serum of SD rats as a initial attack markers of chronic degenerative disease for 4 weeks remarkably decreased in ranges of 14 to $28\%$ by the adminstration of $10\%,\;20\%$ and $40\%$ BA-noodles compared with control group. These results suggest that administration of BA-noodle can not only effectively inhibit chronic degenerative disease, but also may be intervent the aging process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.62-67
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• 1999

Infection rates of oyster ovarian parasite, Marteiliodes chungmuensis and productivity of the oyster shellstock infected with the parasite were investigated at the main seed collection areas in the southern coast of Korea where the extreme bad seed collection of oyster occurred in 1992 and 1993 to evaluate the cause of the bad seed collection. Additionally, the bacterial flora of the sea water and oyster lana were examined to identify the shellfish larva pathogenic bacteria like Vibrio sp. and Pseueomonas sp. In August 1992 to September 1993, infection rate of oyster ovarian parasite, M. chungmuensis at Tongyong, Kyongsangnam province, and Yosu, Chollanam province where the bad seed collection occurred, were $11.8\~100\%$ and $14.3\~100\%$, respectively. But the parasite was not detected in the shellstock collected at Daechon, Chungchongnam province. While a virus-like particle was identified in the cytoplasm of the egg infected by the parasite. The parasite infected egg was not able to fertilize completely. Uninfected egg in the gonad contaminated by the parasite could be able to fertilize but showed an abnormal development till D-shaped larva and then, died of necrosis after D-shaped lana. And some lana developed from low lipid content egg could not develop to the spat and died after the early umbo stage. The predominant bacteria in the oyster lana collected at bad seed collection areas were Pseudomonas sp. and Pseudomonas like bacteria and the occupancy rates were $53.3\~87.1\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.75-82
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• 1999

The hydrolysate of desalinated tuna boiled extract (TBE) were prepared by continuous hydrolysis of TBE using a membrane reactor. TBE and tuna boiled extract hydrolysate (TBEH) were isolated depending on molecular weights. The major molecular weight distributions of TBEH-l0K, TBEH-5K and TBEH-lK were 9,800Da, 3,000Da and 990Da, respectively. The amounts of nucleotides and their related compounds of TBE were 3.47 $\mu$mole/g AMP, 23.75 $\mu$mole/g IMP, 9.07 $\mu$mole/g inosine and 1.89 $\mu$mole/g hypoxanthine. Total content of amino acids having desirable taste (glycine, glutamic acid, alanine, proline, aspartic acid, serine) was about $63\%$ of total amino acid from TBE and about $62\%$ from TBEH. The natural seasoninings were prepared with TBE and TBEH. From the results of sensory evaluations, complex seasoning containing TBEH-1K was almost equal to the shellfish complex seasoning obtained from the market. The mixed sauce which was made by mixing of $50\%$ TBEH sauce and $50\%$ fermented soy sauce was similar to the tradition soybean sauce in product quality and it showed the possibility to be used for the substitute product for acid hydrolyzed soysauce.