• Journal of The Korean Society of Grassland and Forage Science
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• 제9권3호
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• pp.141-147
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• 1989

This experiment was carried out to determine the effects of 13 different application levels of nitrogen(N), phosphorous($P_2O_5$) and potassium($K_2O$) fertilizer at pasture establishment on the winter survival, early spring growth and dry matter(DM) yield, and contents of crude protein(CP) and carbohydrate resewes(CH0-R) of grasses in Suwon from September, 1987 to June, 1988. Winter survival of grasses was high (ca. 90 %) in the plots of N 80 kg, N 120 kg and $K_2O$ application, regardless of $P_2O_5$, while those in zero-N and zero-NPK plots were low as 76 % and 64 %, respectively. Close relationships were observed between winter survival and N & $K_2O$ fertilizer. Early spring growth was vigorous in N-fertilized plots. Heading rate at the first harvest was 50-70 % in all N-plots, regardless of $P_2O_5$ and $K_2O$, while those in zero-N and zero-NPK plots were very low as 20-26 % and 15-18 %,respectively. The DM yield of first harvest was higher in the plots of N 80 kg $ha^{-1}$, regardless of $P_2O_5$ and $K_2O$ levels, and those in zero-N and zero-NPK plots were very low (P < 0.05). The regrowth yleld was not significantly affected by fertilizer levels. The CP content was increased with increasing N level, but CHO-K contents (35-39 %)was not affected by fertilizer levels.Winter survival, early spring growth, DM yield and CP content were significantly influenced by N fertilizer at pasture establishment, regardless of $P_2O_5$ and $K_2O$ application. In this experiment, the compensation effect for spring yield was observed with more N application than usual in next early spring when deficient amount of fertilizer (especially N) was applicated at pasture establishment. Also the optimum application levels of N, $P_2O_5$ and $K_2O$ fertilizer could be recommended as 80, 200 and 70 kg $ha^{-1}$ in new establishing pasture, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• 제24권2호
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• pp.115-122
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• 2004

This study was conducted to investigate the effect of the seeding and harvesting dates on the growth characteristics, dry matter yield and quality of com for silage in alpine area(altitude 800m a.s.l.) of National Livestock Research Institute from 2001 to 2002. The experiment was arranged in a split plot design with three replications. Main plots consisted of three seeding dates, 10 May, 20 May and 30 May. Sub plots consisted of harvesting dates, 15 September, 25 September and 5 October. Tassel height of com was decreased with seeding dates, 30 May, 10 May and 20 May in order, and harvesting date of 5 October was apt to be high. Ear height of com was decreased with seeding dates, 20 May, 30 May, and 10 May in order, and harvesting date of 15 September was the lowest of all treatments. Ear rate of com was decreased with late seeding dates, and it was the highest with harvesting date of 5 October. Dry matter yield was decreased with late seeding dates(P<0.05), and it was increased with late harvesting regardless of seeding dates(P<0.05). Crude protein content of com stover was increased with late seeding dates, and that of com ear was the highest with seeding date of 20 May. And crude protein contents of com stover and ear were the highest with harvesting date of 15 September. NDF contents of com stover and ear were the highest with seeding date of 10 May and 20 May, respectively, and NDF content of com stover was the highest with seeding date of 10 May and there was no difference among treatments in NDF content of ear. ADF content of com stover was 42.1 to 42.6% regardless of seeding dates, and that of com ear was the highest with seeding date of 30 May. ADF content of com stover and ear was increased with early harvesting date excepting for harvesting date of 20 May. These results indicate that 20 May and 25 September would be the optimum seeding date and harvesting date, respectively, for dry matter yield and nutritive value of silage com in alpine area.

• Membrane Journal
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• 제9권4호
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• pp.230-239
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• 1999

Perchlorate ion-selective electrodes in PVC membranes that respond linearly to concentration 106 M were developed by incorporating the quaternary phosphonium salts as a canier. The effects of the chemical structure, the contents of canier, the kind of plasticizer and the membrane thickness on electrode characteristics such as the electrode slope, the linear respone range and the detection limit were studied. With this results, the detectable pH range, selectivity coefficients and AC impedance characteristics were compared and investigated. The perchlorate ion substituents of the quaternary phosphonium salts like tetraoctylphosphonium perchlorate (TOPP) , tetraphenylphosphonium perchlorate(TPPP), and tetrabutylphosphonium perchlorate(TBPP) as a canier were used. The electrode characteristics were better in the ascending order of TBPP < TPPP < TOPP, with the increase of carbon chain length of the alkyl group. Dioctylsebacate(OOS) was best as a plasticizer, the canier contents were better with 11.76 wt% and the optimum membrane thickness was 0.19 mm. Under the above condition, the electrode slope was 56.58 mV/$^P{ClO}_4$,the linear response range was $10^{-1}$\times$10^{-6}$ M, the detection limit was 9.66 x $10^{-7}$ M. The performance of electrode was better than Orion electrode. The electrode potential was stable within the pH range from 3 to 11. The order of the selectivity coefficients for the perchlorate ion was sol < F < Br < 1. With the result of impedance spectrum, it was found that the equivalent circuit for the electrode could be expressed by a series combination of solution resistance, parallel circuit consisting of the double layer capacitance and bulk resistance and Warburg impedance. And solution resistance was almost not appeared and Warburg impedance was highly appeared by diffusion. Then Warburg coefficient was 1.32$\times$$10^74 $\Omega$ $\cdot$ ${cm}^2/s^{1/2}$.

• Journal of the Korean Society of Food Science and Nutrition
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• 제34권8호
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• pp.1265-1273
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• 2005

The purpose of this study was to prepare accelerated salt-fermented anchovy sauce using a shrimp processing byproducts (head, shell and tail) as a fermenting accelerator, and to investigate its physicochemical and enzymatic properties. Four types of sauces were prepared with 0, 10, 20, and 30$\%$ (w/w) addition of shrimp byproduct and fermented at 24$\pm$2$^{\circ}C$ for 360 days. During fermentation, all four type sauces decreased moisture content (67.5$\%$68.0$\%$ to 64.0$\∼$64.8$\%$) and pH (5.52$\∼$7.10 to 5.03$\∼$6.58), but showed increase in their crude protein (7.0$\∼$8.2 to 10.8$\%$) and volatile basic nitrogen contents (40$\∼$75 to 180$\∼$200 mg/100 g of sauce). The ratio of amino nitrogen to total nitrogen contents of control (0$\%$) and sauce with 10$\%$ shrimp byproducts (10$\%$ sauce) were maximized at 270 days, whereas 20$ \% $ and 30$\%$ added sauces were at 180 days. Endoprotease and exoprotease activities of anchovy sauces added with 20$\%$ and 30$\%$ of shrimp byproducts tend to be higher than those of control (0$\%$) and 10$\%$ addition. Proteolytic activities of sauces at pH 9 were about 2 times higher than those at pH 6. Amidolytic activities for LeuPNA decreased remarkably during fermentation, and control (0$\%$) almost lost their activity at 180 days, while additional sauces were relatively stable. These suggest that alkaline pretense of anchovy and shrimp byproducts as a endoprotease mainly contributed to the fermentation of salt-fermented sauces. The protein molecular weight distribution of sauces indicated 2 groups of peaks (peak 1,>70,000 da and peak 2, 3,000$\∼$29,000 da). As the fermentation proceeded, peak 1 tended to decrease in all of sauces, but peak 2 increased rapidly from 30 to 270 days. Optimum fermentation periods of control and 10$\%$ sauces were 270 days and those of 20$\%$ and 30$\%$ sauce were 180 days. The results suggest that shrimp byproduct can be used as accelerator of salt-fermented sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• 제13권1호
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• pp.97-106
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• 1984

The Antarctic krill, Euphausia superba, is drawing attention over the world as the largest source of unutilized proteins in the ocean. For the use of krill as a human food, processing conditions of krill sauce by autolysis and/or commercial proteolytic enzyme digestion were examined. The krill was chopped and mixed with equal weight of water, and hydrolyzed by autolysis and/or commercial proteolytic enzyme digestion. The optimal conditions for hydrolysis of krill were $52.5^{\circ}C$, pH 7.0-7.5, 3 hours by autolysis, $52.5^{\circ}C$, pH 6.3, 3hours by bromelain (0.5 %) digestion, and $52.5^{\circ}C$, pH 7.0-7.5, 3 hours by commercial complex enzyme (5 %) digestion, respectively The maximum hydrolyzing rate of protein were 83.2 % by autolysis, 89.7 % by bromelain digestion, 92.7 % by commercial complex enzyme digestion. After krill meat hydrolyzed by autolysis at optimum condition, inactivated at $100^{\circ}C$ for 20 minutes and filtered with Buchner funnel. Two kinds of products were prepared with krill hydrolysate and preservatives: one contained 10 % of sodium chloride and 0.06 % of benzoic acid and the other 10 % of sodium chloride and 3 % of ethyl alcohol. These products were filled in the sterilized glass bottle and sealed. The pH, volatile basic nitrogen, amino nitrogen, color value (L, a and b values) and viable counts of bacteria were determined during storage at $37^{\circ}C$. The results showed that the products could be preserved in good condition during one month at $37^{\circ}C$. As a method to reduce the sodium level in krill sauce, it is convinced that sodium chloride could be replaced half in partially by potassium chloride. In the products prepared from krill by autolysis, bromelain or commercial complex enzyme digestion, hypoxanthine and 5'-IMP were abundant among the nucleotides and their related compounds as 15.3-20.4 ${\mu}mole/g$, dry solid, 2.2-2.5 ${\mu}mole/g$, dry solid, respectively. The abundant free amino acids were lysine, leucine, proline, alanine and valine. The contents of these amino acids were 67.4 %, 69.4 %, 69.8 % of the total free amino acids of each products. And TMAO, betaine and total creatinine were low in contents. The flavor of krill sauce prepared from krill by autolysis or enzyme digestion was not inferior to that of traditional Kerean soy sauce by sensory evaluation.

• Food Science and Preservation
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• 제15권3호
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• pp.477-482
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• 2008

The quality characteristics of Goami by-product under the mixed enzyme treatment condition of $\alpha$-amylase and cellulase have been compared, and found the highest amount of soluble solids and reducing sugars at the $\alpha$-amylase treated group (A), and the contents revealed to show gradual decrease with the increase of cellulase content. The amounts of total dietary fiber and total sugars did not show large difference by both of enzyme concentration. The result of sugar analysis revealed the presence of all $G{\sim}G5$ in all treatment groups, and the content of malto-oligosaccharide recorded the highest content of 2,200 mg% at the $\alpha$-amylase treatment group (A). When the quality characteristic of the hydrolyzed powders manufactured by the optimum hydrolysis condition was compared, no significant color difference was found between samples. Among the contents of dietary fibers, insoluble dietary fiber was found to present in the lowest content of 6.95% at the Goami flour (GF) and the Goami by-product powder (GBPP) and Goami by-product hydrolysate powder (GBPHP) resulted the similar content around 14% and the highest soluble dietary fibers content was found in Goami by-product hydrolysate powder (GBPHP), which was followed by in the order of Goami by-product powder (GBPP) and Goami flour (GF), but the content variation was not large. The free amino acid was found to be highest in Goami by-product hydrolysate powder (GBPHP) followed by in the order of Goami by-product powder (GBPP) and Goami flour (GF). In the sugar analysis, the Goami by-product hydrolysate powder (GBPHP) was found with all $G{\sim}G5$ sugars by showing the highest amount of 1,800 mg% At the Goami by-product powder (GBPP), $G{\sim}G2$ sugars were detected with about 66 mg% and malto-oligosaccharides were not detected at the Goami flour (GF). Based upon the results, the functionality of Goami by-product hydrolysate powder (GBPHP) was found to be enforced compared to Goami flour (GF) and Goami by-product powder (GBPP), which allow us to expect it to be used as the various rice processing food source.

• Journal of the Korean Society of Food Science and Nutrition
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• 제34권6호
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• pp.755-758
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• 2005

Wild grape is a traditional medicine plant in north-eastern part of Asia and has been known to have healing properties for various illnesses. This study was to determine the optimum extraction condition and antioxidant activity of ethanol extracts of wild grape (V. coignetiae) seed. Also, organic solvent fractions of hexane, chloroform, ethyl acetate and butanol were obtained from the ethanol extract of wild grape seed at different temperatures. Total ethanol extraction yield of wild grape seed ranged from $4\%\;to\;12\%$ depending on the ethanol concentration, extraction temperature and time condition. The highest extraction yield of $11.9\%$ was obtained at $90\%$ ethanol condition for 12 hour at $70^{\circ}C$. However, the strongest free radical scavenging effect $(RC_{50})$ with $20.93\mu g/mL$ was observed in $70\%$ ethanol extract of wild grape seed extracted for 6 hour at $70^{\circ}C,\;while\;RC_{50}\;with\;40.42$\mu g/mL$ was observed in $90\%$ ethanol extract for 12 hour at $70^{\circ}C$. Antioxidant activity of ethanol extracts of wild grape seed increased as total phenol contents increased. Among each fraction obtained from organic solvents, ethyl acetate fraction was found to have the strongest $RC_{50}\;(8.6\mu g/mL)$ and 636.77 mg GAE/g phenol contents .

• Horticultural Science & Technology
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• 제28권3호
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• pp.462-468
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• 2010

Top parts of $Dendranthema$ $zawaskii$ var. $yezoense$ (DZY) and $Cosmos$ $bipinnatus$ (CB) are believed to contain substances with antioxidant effects and activity. Present experiments were undertaken to investigate an adequate and efficient extraction method which ensures the highest yield of antioxidant components. Extraction yield was 1.11-1.92 times higher by ultrasonic method than other methods in both species. By 45 minute ultrasonic extraction, total polyphenol contents reached the highest level, $80.70mg{\cdot}g^{-1}$ tannic acid equiv./DW in $Cosmos$ $bipinnatus$ and total flavonoid contents $50.41mg{\cdot}g^{-1}$ naringin equiv./DW in DZY. DPPH radical scavenging activity was almost the same among extraction methods or slightly higher in reflux extraction. The highest DPPH radical scavenging was observed by reflux extract in CB ($RC_{50}=0.135mg{\cdot}mL^{-1}$). ABTS radical scavenging activity was the highest by 15 minute ultrasonic wave in DZY and CB, $RC_{50}=0.159mg{\cdot}mL^{-1}$ and $RC_{50}=0.139mg{\cdot}mL^{-1}$, respectively. High ferrous ion chelating effects were obtained by 30-minute ultrasonic wave in DZY ($RC_{50}=0.803mg{\cdot}mL^{-1}$). Extracts of top parts of DZY obtained by reflux method showed the highest inhibition effect against peroxidation of linoleic acid, and extract of CB obtained by ultrasonic for 45 minutes showed the highest inhibition effect. In conclusion, optimum extraction method should be adjusted according to plant species and antioxidant substances.

• Horticultural Science & Technology
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• 제33권1호
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• pp.47-54
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• 2015

This research was conducted to investigate the changes in moisture retention capacities of expanded rice-hull (ERH)-based root media and their influences on the growth of mother and daughter plants in vegetative propagation of 'Seolhyang' strawberry. The proportion of water at the container capacity of ERH medium was in the range of 20 to 23%. This range was lower than the 60 to 66% of strawberry-specialized medium, the 30 to 34% of soil mother material (SMM) and the 30 to 35% of loamy sand. The moisture content of ERH was reduced to 10 to 12% at 8 hours after irrigation, and there were large variations among replications of ERH medium. Among four kinds of root media formulated to contain ERH, the medium of ERH + coir dust (CD) (55 + 45%, v/v) had 26.5 and 32.5% water contents at 20 and 40 days after irrigation to daughter plants, respectively. The m edia o f ERH + sandy loam (S L) and E RH + S MM showed similar trends i n moisture r etention. The pH and EC i n the all root media tested were in the range of 6.7 to 7.1 and 0.03 to $0.08dS{\cdot}m^{-1}$, respectively. The pHs and ECs measured at 20 and 40 days after irrigation were not significantly different in each root medium. Among the root media formulated to contain ERH, the growth of daughter plants was the highest in the treatment of ERH + SL (55 + 45%, v/v). As the blending rate of coir dust was elevated in the ERH + CD media, moisture retention capacity increased gradually, but the growth of daughter plants became worse even though the medium showed higher moisture retention capacity than other root media tested. The growth of roots and aboveground tissues of daughter plants deteriorated in the root media formulated by blending ERH + perlite (PE) at various ratios. The results of this research suggest the optimum formulations of root media and management of moisture content in raising of strawberry daughter plants when ERH is a component of root media.

• Korean Journal of Food Science and Technology
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• 제34권6호
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• pp.1048-1056
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• 2002

Quality of fresh ginger deteriorates rapidly during low temperature storage, and its storage life is short due to sprouting and microbial spoilage. The objectives of this research were to develop, using additives, a minced ginger product, which could maintain acceptable quality for over 30 days, and to investigate its quality changes during the cold storage. Storage stability of minced ginger product was investigated from the standpoint of the inhibition of brown discoloration, gas formation and liquid-solid separation. Fresh ginger was peeled and ground to produce minced ginger (control). Sodium bisulfite, L-cysteine, NaCl, sodium benzoate, modified starch, and/or xanthan gum were added to the control to minimize quality loss during storage, and to develop an optimum formula (A) of minced ginger. Samples were packed in Nylon/PE films, stored at $5^{\circ}C$, sampled at a 30-day interval, and subjected to quality evaluations. Changes in pH, surface color, gas formation, liquid-solid separation, contents of free amino acids, free sugars, organic acids, and fatty acids were determined. Gas formation was effectively inhibited in samples with sodium benzoate and/or NaCl. Samples with xanthan gum did not result in liquid-solid separation. L-Cysteine and sodium bisulfite were effective in controlling discoloration. pH decreased during storage in all samples, except sample A. Organic acid contents of all samples increased during storage, with lactic acid content showing the highest increase. Free amino acid content decreased with increasing storage time. Free sugar content of all samples decreased during storage. Sensory results showed sample A maintained acceptable quality until 90 days of storage. These results suggest that quality of minced ginger could be successfully maintained with the additions of selected additives for up to 90 days.