• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.55-69
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• 2001

To study the possibility of agricultural utilization of seafood processing wastewater sludges, the changes of temperature and humus, the form of organic matter and nitrogen and the germination ratio of plant during the composting were investigated. The results were summarized as follows. Temperature was rapidly increased at early stage of composting, reached to $67{\sim}76^{\circ}C$ in highest temperature at 3~5 days, and then decreased gradually fallen to $40{\sim}50^{\circ}C$ at 19 days after composting, at the point was upset firstly. The third upset was conducted at 60days after composting, and then the temperature was little changed. The contents of total organic matters in the compost for composting were down 4.5~8.0%. Ether extractable materials, resins and hemicellulose contents of the organic matters for composting were decreased with 35~77%, 32~69% and 19~30%, respectively. And cellulose, lignins and unknown materials contents in the organic matters for composting were increased a little, but water soluble polysaccharides of organic matters were little changed. Total nitrogen, amino sugar and amino acid nitrogen contents in the compost for composting were decreased with 20~42%, 11~49% and 23~65%, respectively. The contents of humic acid in the compost for composting were little changed, but contents of fulvic acid in the compost for composting were decreased gradually. Germination ratio of radish, chinese cabbage and cucumber were over 90%, when the compost produced at 30 days after composting was tested on plant germination.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.859-865
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• 2007

The chemical components and antioxidative activity of Korean gold kiwifruit were investigated. The values of pH, soluble solid and total acidity were 4.43${\pm}$0.16, 17.01${\pm}$0.04$^{\circ}Brix$, and 0.082${\pm}$0.02%, respectively. Hunter L, a, and b values were 49.80${\pm}$0.24, -6.79${\pm}$0.02, and 19.72${\pm}$0.18 value, respectively. Proximate compositions were as follows; moisture 78.62${\pm}$2.26%, crude protein 1.34${\pm}$0.25%, crude lipid 0.70${\pm}$0.06%, crude fiber 1.99${\pm}$0.13%, crude ash 0.99${\pm}$0.26%, and carbohydrate 16.36${\pm}$1.23%, respectively. Mineral elements were K 265.86${\pm}$5.00, P 71.82${\pm}$29.18, and Ca 23.84${\pm}$2.10 mg%, respectively. Free sugar compositions were sucrose (1.04${\pm}$0.18%), glucose (2.17${\pm}$0.21%) and fructose (1.86${\pm}$0.11%). Amino acid contents of Korean gold kiwifruit was very rich in glutamic acid 86.51 ${\pm}$5.58 mg/100 g and deficient in tyrosine 15.00${\pm}$4.91 mg/100 g. Organic acid compositions were quinic acid (6.65${\pm}$0.21 mg/g), malic acid (1.62${\pm}$0.13 mg/g) and citric acid (4.82${\pm}$0.21 mg/g). Contents of ascorbic acid and total phenols were 0.27${\pm}$0.06 mg/g and 0.047${\pm}$0.002 mg/g, respectively. The DPPH radical scavenging activity and reducing power of the water extract from Korean gold kiwifruit was 86.87% and 1.96 at a concentration of 25 mg/mL. The water extract showed considerable antioxidative activity against linoleic acid autoxidation in a dose-dependent manner.

• Food Science and Preservation
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• v.24 no.8
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• pp.1129-1137
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• 2017

The fringe tree, Chionanthus retusus (Oleaceae) has been used as a natural remedy that helps a paralytic stroke, dementia, phlegm and malaria. This study was conducted to investigate the antioxidant and anti-aging activities of water extracts obtained from the flesh of C. retusus by reflux extraction at room temperature and $80^{\circ}C$, and pressure heating extraction at $110^{\circ}C$, for an increment of their practical use. The highest extraction yield from the flesh of C. retusus was 67.94% extract by pressure heating extraction at $110^{\circ}C$. The content of total polyphenol compounds was the highest by 72.71 mg/g in $80^{\circ}C$ extract by reflux extraction. The highest content of total flavonoid compounds was 7.60 mg/g at $110^{\circ}C$ extract. The results of soluble protein and reducing sugar contents showed the highest content of 4.93 mg/g and 46.77 mg/g in $110^{\circ}C$ extract, respectively. In the analysis of DPPH radical scavenging activity, all extracts showed an excellent effect of 92% in 1.0 mg/mL concentration. The highest effect of ABTS radical scavenging activity was 88.67% at $110^{\circ}C$ extraction in 1.0 mg/mL concentration. Nitrite scavenging ability was the highest as 66.16% at $110^{\circ}C$ extract at pH 1.2 and 1.0 mg/mL concentration. The results of SOD-like activity and xanthine oxidase inhibition activities showed the highest effect of 14.95% and 59.45% at $110^{\circ}C$ extract in 1.0 mg/mL, respectively. Tyrosinase inhibition activity for whitening effect was the highest of 35.31% at $85^{\circ}C$ in 1.0 mg/mL. In the analysis of anti-aging effect, collagenase and elastase inhibition activity showed the highest effects of 37.78% at $110^{\circ}C$ and 20.39% at $80^{\circ}C$, respectively. All results of antioxidant activities and anti-aging effects increased along with the concentration increases. These results indicated that the extracts extracted from the flesh of C. retusus at $80^{\circ}C$ and $110^{\circ}C$ have a large amount of useful ingredients, an excellent antioxidant activity, like as DPPH and ABTS radical scavenging activity, and anti-aging effects to develop functional products than those of $25^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.174-180
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• 2000

This work was carried out to investigate the effects of mashing proportion of meju(as wet weight basis of raw soybean) to 20% salt brine on the chemical compositions and sensory characteristics of kanjang. By increasing the salt brine proportion in the kanjang mash, total nitrogen, TCA soluble nitrogen and total free amino acid content in kanjang were decreased accordingly, but although pH values and organic acids content were not different noticeably, the major organic acids in kanjang, lactic acid, pyroglutamic acid and acetic acid were increased up to the mashing proportion of 1:2 from 1:1 and pH values decreased up to that of 1:2.5. Residual sugar content in 1:1 kanjang was exceptionally high. The major free amino acids in kanjang were glutamic acid, lysine, alanine and leucine. The acceptability scores of kanjang tested by sensory evaluation were decreased in inverse proportion to the salt brine proportion of kanjang mash, but those of kanjang samples with $1:1{\sim}1:2.5$ mashing proportions were not significantly different but that of 1:3 different from 1:1 statistically at 5% level. The major chemical compositions, significantly effective to the acceptability of kanjang, were found to be glutamic acid and free amino acid by statistical analysis.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.376-387
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• 2019

Melons are mostly grown in soil, but it is susceptible to damage due to injury by continuous cropping such as Fusarium wilt and root rot. Hydroponic cultivation system can overcome the disadvantages of soil cultivation with precise nutrition management and a clean environment. When using the coir substrate, the most environmentally friendly organic substrate used for hydroponics, it is analyzed how the growth and fruit quality of the melon depends on the ratio of chips and dust and the amount of irrigation. The purpose of this study was to provide the basic data of melon hydroponics when cultivated in spring. The two types of the coir substrates used in the experiments were chip and dust ratios of 3 :7 and 5 : 5 respectively. The substrate with high dust ratios had excellent physical characteristics, such as container capacity and total porosity, and the drainage EC level showed a high value of $3.0-6.8dS{\cdot}m^{-1}$. When the amount of irrigation is provided based on the drainage rate, the group provided the nutrient solution on the basis of 10% drainage supplied 91 L per plant, which was reduced by about 30% compared to the group with the highest water supply. In addition, the total drainage showed less than 10 L per plant with a minimum water supply and was reduced by 30 - 70% in substrate with a high dust rates. In substrate with high water supply and high dust ratio, leaf growth and fruit enlargement were good, and the soluble solids content varies greatly from cultivar to cultivar. If you provided the amount of irrigation based on 10% drainage rate, the fruit weight will be decreased, but the amount of irrigation can be reduced. Therefore, it is considered that managing the water & nutrient properly taking into account the characteristics of coir substrate and cultivar can produce melon of uniform quality using hydroponics.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.186-195
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• 2015

This research was conducted to investigate effect the plant growth regulators (PGRs) on the characteristics of fruit and flesh softening, using GA3 and thidiazuron (TDZ) treatments in 'Heukboseok' grapes. The total yield obtained under PGR treatment was 88.3% lower than the target production when a single treatment with $GA_3$ of low concentrations was used, but the expected yield was recovered by combined treatment with TDZ and $GA_3$. When harvested on the basis of color, the harvest rate up to 100 days after full bloom (DAFB) was low with the $GA_3$ single treatment, but was increased by the addition of TDZ, with the second TDZ mixed treatment being particularly effective. The soluble solids content in the PGR-treated samples demonstrated no significant changes after 90 DAFB, while the acidity content decreased rapidly starting from 90 DAFB. Measured on the basis of sugar and acidity content, maturity was reached much earlier in treated fruit than in the non-treated fruit. Firmness was maintained at a higher level until the final harvest time after PGR treatment compared to untreated grapes according to epidermis thickness and flesh density increase to activity cell division and expansion by $GA_3$ and TDZ. In particular, the fruit quality was improved based on the delay of softening in primary and secondary treatments of $25mg{\cdot}L^{-1}\;GA_3+2.5mg{\cdot}L^{-1}$ TDZ. The production of seedless fruit was difficult, even with the inclusion of TDZ, reaching the highest seedless rate of only 65.5%. Fruit cracking was rare, occurring at a rate of about 0.0~0.9% in all treatments. Accordingly, 'Heukboseok' grapes should be harvested within 100 days after full bloom (DBFB) before a rapid decrease of firmness, conferred by primary and secondary treatments with $25mg{\cdot}L^{-1}\;GA_3+2.5mg{\cdot}L^{-1}$ TDZ.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.419-424
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• 1998

Removal of monochloropropanediol (MCPD) and improvement of quality of the soy-sauce made from acid-hydrolyzate of defatted soy protein (SAHSP) were examined by fermenting the soy-sauce with soy-sauce koji or koji plus Pediococcus soya or/and Saccharomyces rouxii. The overall fermentation process performed in this work consisted sequentially of autodigestion of soy-sauce koji $(at\;45^{\circ}C\;for\;12\;days)$, lactic acid fermentation $(at\;30^{\circ}C\;for\;14\;days\;in\;S3\;and\;S4)$, ethanol fermentation $(at\;30^{\circ}C\;for\;14\;days\;in\;S2\;and\;S4)$,and aging $(at\;25^{\circ}C\;for\;20\;days)$. At the end of the autodigestion period, the highest MCPD removal (from the initial 38.6 ppm to 1.3 ppm) was observed in the S-2. Reducing sugar contents of the S-2 and S-4 sharply decreased from the 30th day of incubation, from the initial concentration of about 5.0% to less than 0.5% at the end of the process. Total soluble nitrogen content of all the soy-sauce products slightly increased during the overall fermentating period.The level of free glutamic acid, a major amino acid that is known to determine the taste of soy-sauce was determined to be an average value of $1270{\sim}1323\;mg/100\;mL$ of soy-sauce. The results of sensory evaluation of the fermented SAHSPs show that qualities of the S-2 and S-4 samples are nearly on the same level with that of the commercially fermented soy-sauce (p<0.05). This result suggests that the fermentation process in this work, especially the process performed with S. rouxii has a good effect for removing MCPD from SAHSP and also for improving quality of the SAHSP product.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.448-455
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• 2004

Changes in quality characteristics of Bijijang (fermented soybean curd residus) prepared at $35^{\circ}C\;and\;40^{\circ}C$ for 0, 12, 24, 36, and 48 hr were investigated. Acidity of Bijijang increased, whereas pH and Hunter's color values decreased during fermentation. Immediately after Bijijang preparation, ${\alpha}-and\;{\beta}-amylase$ activities were very low, ${\beta}-Amylase$ activity during fermentation increased rapidly, with those fermented at $40^{\circ}C$ higher than at $35^{\circ}C$. Neutral pretense activity was significantly higher than acidic pretense activity, and increased gradually after 12 hr. Change in total nitrogen content in Bijijang was insignificant, whereas contents of amino-type and water-soluble nitrogens increased significantly during fermentation. Major free amino acids of Bijijang were Arg, Pro, Glu, Thr, Ser, and Lys at initial fermenting stage, and, as fermentation progressed, contents of Cys, Met Glu, Ile, Leu, and Phe increased. Reducing sugar contents of Bijijang fermented at $40^{\circ}C$ were higher than those fermented at $35^{\circ}C$. Sucrose content decreased and glucose content increased. Glucoside (genistin and daidzin) contents decreased and aglycone (genistein and daidzein) contents increased during preparation of Biji and fermentation of Bijijang. Contents of free sugars and isoflavones were higher in Bijijang fermented at $40^{\circ}C$ than at $35^{\circ}C$. Based on these results, fermentation at $40^{\circ}C$ for 48 hr was determined to be optimum fermentation condition for Bijijang.

• Food Science and Preservation
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• v.19 no.1
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• pp.87-94
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• 2012

This study was carried out to investigate the physicochemical characteristics of maturating and dried jujube. The moisture contents of the unripe and ripe jujube were found to be 84.66 and 66.45%, respectively, but that of the dried jujube was 31.48%. The crude-fat and crude-ash contents of the dried jujube were much higher than those of the maturing jujube. The carbohydrate contents of the unripe, ripe, and dried jujube were found to be 13.51, 27.94, and 61.70%, respectively, and the soluble-protein contents were 0.88, 1.73, and 3.71%. The reducing-sugar content of the dried jujube was 18.82%, higher than that of the ripe jujube. The sucrose contents of the unripe and ripe jujube were 10.15 and 16.66 g/100 g, respectively, and that of the dried jujube was 33.46 g/100 g. The major fatty acids that were found to compose jujube were palmitic, oleic, pamitoleic, linoleic, and linolenic acid. The myristoleic and arachidonic acid contents were higher in the dried jujube than in the ripe jujube, but the palmitoleic acid content was lower in the dried jujube than in the ripe jujube. The major minerals of jujube were found to be Ca, K, Mg, and P, and the total mineral contents of the unripe, ripe, and dried jujube in this study were 343.38, 584.94, and 331.56 mg/100 g, respectively. The polyphenol contents of the unripe, ripe, and dried jujube were 309.12, 248.80, and 23.34 mg/100 g, respectively, while the vitamin C contents were 610.04, 310.22, and 423.27 mg/100 g.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.416-423
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• 2004

This experiment was carried out to investigate the effect of loquat (Eriobotrya japonica Lindley) extract on the acid production and growth of lactic culture in reconstituted skim milk. The supplementation level of loquat extract to reconstituted skim milk was 10％, 15％ and 20％. Reconstitued skim milk containing loquat extract was fermented by single of mixed culture of Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus casei. General compositions of loquat extract, changes of viable cell count, pH and titratable acidity during fermentation were determined. Chemical compositions of loquat extract were 91.5％ moisture, 0.2％ crude ash, 8.6$^{\circ}$ Brix soluble sugar, 0.34％ total acid, and 4.11 in pH. Supplementation of loquat extract stimulated acid roduction and growth of lactic acid bacteria. Among supplementation levels, a group that was fermented by a single culture of Str. thermophilus with 10％ loquat extract was shown the highest viable cell count (2.10${\times}$10$\^$9/ CFU/mL) at 12 hours after inoculation. When loquat extract was added to reconstituted skim milk at the level of 10％, all mixed cultures of lactic acid bacteria showed higher acid production and the number of viable cell count than 3 kinds of single cultures. Especially, the growth of mixed culture of Str. thermophilus and Lac. acidophilus was promoted by the addition of 10％ loquat extract. Therefore, it was suggested to manufacture the yoghurt with the addition of 10％ loquat extract and the inoculation of mixed culture of Str. thermophilus and Lac. acidophilus for on the stimulation of growth of the lactic culture.