• Journal of Korean Society of Forest Science
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• v.40 no.1
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• pp.63-69
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• 1978

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potential1y valuable resourses, As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Pinus, Quercus, and Populus grown in Korea can be enhanced by learning their chemical properties. However, the chemical study of tree bark grown in korea have never been undertaken. In the present paper, the studies on the chemical properties of bark comprise carbohydrates, lignin, and extractives, composition of reducing sugars and five essential elements. The results may be summarized as follows: 1. Bark are much richer in quantity of lignin and extractives than the corresponding wood, and are chiefly consisted of lignin, extractives and carbohydrates orderly. It is the same with ash contents. Alcohol-benzene extractives of populus bark are the highest among three genus. 2. Although glucose constitutes the major sugar in both pine and hardwoods bark, in pinus, arabinose and xylose are the next but in hard woods, the next is xylose. 3. Essential elements, Ca and Kjeldahl-N are higher in the bark than in the wood. Ca content is the highest among others, and N,K followed it. Essential elements are higher in Quercus than in Populus and pinus.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.179-184
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• 1998

As a way of mass process of onion, Allium cepa L., the oleoresin decompressed and concentrated is an alternative process to minimize lowering in the quality of onion during storage, to improve the original flavor and taste, and to increase variety as processing aids. This study was performed to investigate on the quality stability during storage of oleoresin. Oleoresin product was manufactured by mixing a concentration of onion juice and ethanol extract homogenously, emulsified by an additional 2% PGDR(polyglycerol condensed ricinoleate) and 1% cysteine. During 60 days storage at 5$^{\circ}C$, $25^{\circ}C$ and 4$0^{\circ}C$ the total sugar content in oleoresin product was very stable, and absorbances at 420nm as browning reaction index were 0.38, 1.53 and 3.32, respectively, addition of 1% cysteine retarded the browning reaction effectively. When oleoresin product was centrifuged(2000$\times$G, 60 minutes), the volumes of emulsion level without separation were 96.8%, 94.1% and 9.06%, respectively during 20 days, 40 days and 60 days storage at 5$^{\circ}C$, and those during 60 days storage at $25^{\circ}C$ and 4$0^{\circ}C$ were appeared to be 83.2% and 75.4%. Showing lower level as increasing storage temperature. Antioxidant indexes(AI) of soybean oil added 1% oleoresin without storage and 0.02% BHA were 1.39 and 1.72. The former showed 80.8% antioxidant activity on induction time extension effect of the latter. Antioxidant indexes of oleoresin decreased slightly as increasing storage temperature and were 1.37, 1.30 and 1.08. Total pyruvate contents were 89.9%, 79.7% and 65.2%, respectively during 60 days storage at 5$^{\circ}C$, $25^{\circ}C$ and 4$0^{\circ}C$. Rate constant, Q10 value and activation energy were 1.381~4.735 mmol/$\ell$.hr, 1.537~1.694 and 11.649 ㎉/g mole for the reduction of pyruvates in the range of storage temperatures during oleoresin storage.

• Journal of Life Science
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• v.25 no.5
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• pp.557-567
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• 2015

To increase the marketability of Dolsan leaf mustard Kimchi, seasonings were prepared by sea tangle and Lentinus edodes. Gat Kimchi A (GK-A) and Gat Kimchi B (GK-B) were prepared by addition of complex seasoning with Sea tangle (CSS), complex seasoning with Lentinus edodes (CSL), respectively and evaluated the quality characteristics. GK-A contained high minerals and dietary fiber and showed the effect of delaying pH-lowering and acidity-rising. There were no significant differences in salinity test after 70 days. Reducing sugar of test groups was higher than control. During the fermentation, Leuconostoc sp. was grown in GK-A and GK-B than control. Growth of control's Lactobacillus sp. increased 20 days after. Up to 30 days, lightness of control was high. Yellowness were increased browning potential in GK-B, 20 days after. From the initial to 10 days, Hardness of GK-A showed higher than the others. glutamic acid and aspartic acid content of GK-A was higher significantly than the others in the entire fermentation period (p<0.05). At 0, 10, 30 days, sweet-tasty amino acids of GK-A showed a significantly higher level than the others (p<0.05). From 10 days to 40 days of fermentation, the sensory evaluation of GK-A is better than the other groups. Comprehensively reviewed the above results, the conclusion is as follows: CSS made with sea tangle as a main ingredient. GK-A by seasoning the CSS to 90 g GK-A is expected as a new Dolsan leaf mustard products that can provide flavor and nutrition to the consumer at the same time.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.141-146
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• 1994

As a foundational study for processing persimmon leaves tea, the physico-chemical characters were investigated in persimmon leaves from Chungdo Bansi, Sagoksi, Kyungsan Bansi and Hiratanenasi during growth. Flesh weights increased rapidly until the middle of May and then decreased slightly. Moisture contents decreased continuously from $79{\sim}81%$ at the beginning of May during growth. Water soluble tannin contents reached $1.55{\sim}2.25%$, maximum values at the middle of May and at the beginning of June, and increased again at the middle of July and then decreased. Contents of catechins, precursor of condensed tannin, indicated $12{\sim}27\;mg%$ at the middle of May and reached $17{\sim}34\;mg%$, maximum values at the middle of June. Contents of catechin were low in order of (+)-catechin, (-)-epicatechin, (-)-epicallocatechingallate, (-)-epigallocatechin and (-)-epicatechingallate. Sugars present in persimmon leaves were composed of sucrose, glucose, fructose, raffinose and mannitol. Sucrose increased continuously, glucose and fructose decreased during growth. Raffinose content was less than 0.1%. Glucose and fructose took more than 90% until the beginning of May, and then sucrose took up $60{\sim}80%$ of total sugar contents. Total vitamin C contents indicated maximum values at the middle of May and at the beginning of June in Chungdo Bansi, Sagoksi and Kyungsan Bansi, maximum vaule at the middle of July in Hiratanenasi. From the basis of these data It was suggested that proper period for picking persimmon leaves prior to processing persimmon leaves tea was from the middle of May to the beginning of June. Since maximum values for most of chemical components occurred at the middle of May and at the beginning of June and persimmon leaves thicken after the middle of June.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.239-244
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• 2020

Effect of 6kg large unit with the carton box (20% open ratio) and MA box (10,000cc·m^-2·day^-1·atm^-1 oxygen transmission rates modified atmosphere package), and the 100g small unit with MA film on asparagus sensory quality were evaluated. The CO₂ concentration depended largely on the packing unit and maintained at around 3% in small MA packages, whereas in the MA box increased to 12%. Ethylene concentration rapidly increased until after 3 days of storage in MA packages and then decreased to maintain 5μL·L^-1. Unrelated to the unit size, the lower weight loss was obtained in MA packages. A significant difference in visual quality was shown since the 15th day, the best and worst were the MA box and small MA package on the finish day. Off-odor was the highest in small MA packages and the lowest in the carton box (< 3.0). Although there was no significant difference in firmness among all treatments, the packages showed the highest firmness in tips and stems, respectively. The sugar content and hue angle decreased during storage, but there was no statistical difference in all treatments. EL was lowest and highest in small MA package and carton box, respectively. On the 10th day, the total aerobic bacteria was lowest in small MA packages, but no significant difference on the 20th day. E. coli was not found in all treatments on the 10th day, while it was the lowest in the MA box on the 20th day. The mold and yeast were not observed during the whole storage. Based on the above results, the carton box packaged with 10,000cc OTR film was more effective in maintaining the quality of green asparagus with the suitable CO₂ concentration for asparagus cold storage.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.202-218
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• 1976

In this experiment American Summer Pairman apple was selected as test fruit in order to study the effect of sub-atmospheric pressure storage in the apple. keeping a certain pressure condition, a new sub-atmospheric pressure system was designed and constructed in which fruits were stored at $25^{\circ}C$ under two different atmospheric pressure conditions such as Normal Atmospheric Pressure (NAP) and Sub-Atmospheric Pressure (SAP). Moreover, they were divided into plots of 5% and 0% of $CO_2$, on the basis of gas composition. Under these conditions, the amount of respiration and ethylene evolution, and the changes of intercellular gas composition and organic components were investigated throughout the storage. The results obtained are as follows: (1) The intercellular gas was exhausted so rapidly by the SAP treatment that the gas equilibrium in the tissues reached within 5 minutes. (2) The amount of respiration was found to be higher in plots of NAP than SAP, and under the conditions, controlling $CO_2$ content, plots of $CO_2$ 5% were lower in the amount of respiration than $CO_2$ 0%. The climateric rise was revealed more slowly in plots of the SAP than NAP. These results indicate that the SAP treatment was an efficient method for controlling the respiration of fruits. Furthermore, these results were also realized with the results of the respiratory quotient (R.Q) and intercellular gas composition. (3) Evolution of ethylene, the ripening hormone in plant, was shown the similar tendency to the climacteric pattern of respiration; at the stage of climacteric maximum, the maximun amount of ethylene was found earlier in plots of NAP than SAP, and post climacteric stage was prolonged in the plots of the SAP compared to those of the NAP. The ethylene concentration in tissue appeared lower in plots of the SAP than NAP, which might suggest that the SAP treatment was caused to restriction of ethylene evolution. (4) Effects of the SAP treatment mentioned hitherto were proved also with the test of the external appearance such as changes of color and freshness, firmness, rotting and weight loss. (5) In the investigation of organic components, vitamin C and organic acids varied less in plots of SAP than NAP. Specially, it was remarkable that the loss of malic acid was least decreased by the SAP treatment. These effects of the SAP treatment were distinctive in the changes of the ratios of malic and citric acid to total acid, and the ratios of free sugar to free acid.

• Food Science and Preservation
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• v.22 no.3
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• pp.399-407
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• 2015

Sumaeyaksuk (Artemisia Argyi H.) is one of the original mugwort spices in Namhae-gun, Korea. This study was conducted to investigate the physicochemical characteristics and biological activities of water extracts from dried and aging Sumaeyaksuk samples during the May-July harvest season. One (SD) was dried under shade for 12 days, while the other (AD) was aged for 7 days at $60^{\circ}C$ and then roasted for 220 minutes at over $90^{\circ}C$. Glucose was solely detected as a free sugar, and its SD and AD content were $0.42{\pm}0.02{\sim}0.43{\pm}0.01g/100g$, and $0.41{\pm}0.02{\sim}0.47{\pm}0.04g/100g$, respectively. The total phenolic contents of SD were $1.85{\pm}0.09{\sim}3.45{\pm}0.14g/100g$, which were higher than those of AD ($1.29{\pm}0.08{\sim}2.90{\pm}0.08g/100g$). The antioxidant activities of the water extract powder from each Sumaeyaksuk were assessed by different in vitro methods, such as the DPPH and ABTS radical scavenging activity, FRAP, and decoloration prevention activity in ${\beta}$-carotene linoleic system. The DPPH and ABTS radical scavenging activity of AD extract were significantly higher than those of the SD extract (p<0.05). Moreover, at the concentrations of 31.25, 62.5, 125, 250, $500{\mu}g/mL$, the FRAP of the SD-May extract showed $1.67{\pm}0.58{\sim}489.90{\pm}7.59{\mu}M$, while the AD-July extract showed $9.70{\pm}1.07{\sim}590.40{\pm}7.45{\mu}M$. The ${\beta}$-carotene decoloration prevention activity of the SD-May and AD-July extracts were $25.53{\pm}2.85{\sim}81.43{\pm}2.56%$, $35.98{\pm}2.22{\sim}79.00{\pm}1.42%$, respectively. Based on these results, the extracts of SD-May and AD-July were promising as a functional food source due to their high antioxidant activites.

• Food Science and Preservation
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• v.19 no.5
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• pp.672-680
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• 2012

To determine the characteristics of four different sweet pumpkins (Minimam, Bojjang, Ajikuroi and Kurijiman), juices were made from these varieties. The carotenoids in the flesh were 1.5~2 times higher than those in the skin and were highest in the flesh of the Minimam pumpkin among all the pumpkin varieties studied. The vitamin A contents were higher in the skin than in the flesh, and Minimam had the highest vitamin A content (2,016.57 IU/100 g) while Kurijiman had the lowest (998.83 IU/100 g). The vitamin C contents varied from 43.21 to 82.35 mg%, but there were no significant differences between the flesh and the skin. That of Kurijiman was the highest among the varieties studied. The major mineral of these varieties was potassium, which was highest in the flesh of Ajikuroi, followed by phosphorus. The antioxidant activities of the sweet pumpkin water extracts were higher in the skin than in the flesh. The $EC_{50}$ of the Minimam skin was the highest (4.01 mg/mL), and that of the Ajikuroi flesh was the lowest. The sweet pumpkin juice yields were 69.5~89.4%, with significant differences shown according to the variety. That of the peeled Ajikuroi's flesh was the highest. The pH was 7.17~7.83, and the unpeeled sweet pumpkin's pH was higher than that of the peeled sweet pumpkin. The Brix degree was $12.5{\sim}16.6^{\circ}Brix$, with that of the unpeeled Bojjang being the highest($16.1^{\circ}Brix$) and that of the unpeeled Ajikuroi the lowest ($12.7^{\circ}Brix$). The sweet pumpkin beverage made with pressed juice was adjusted by pH 3.5 with citric acid, and the Brix degree was maintained at the $12^{\circ}Brix$ with sugar. The adjusted beverage, which was the peeled pumpkin flesh juice, had suspension stability for a short time. The sweet pumpkin beverage had a certain flovor and a slimy mouthfeel. Bojjang and Kurijiman were evaluated as the best in the terms of taste and color, but the peeled Minimam and Bojjang showed the best results overall.

• Food Science and Preservation
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• v.23 no.6
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• pp.804-810
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• 2016

This study aimed to compare the quality characteristics of developed rice Jochung (E) with those of commercial-rice Jochung (A, B, C, and D). The total soluble solid, reducing sugar, and dextrose equivalent of developed rice Jochung were $80^{\circ}Brix$, 44.53%, and 56.94%, respectively. The pH and titrable acidity were 6.25 and 0.19%, respectively. The color difference value (${\Delta}E$) of developed rice Jochung was 74.42, which was significantly lower than the other samples investigated. The light transmittance and total polyphenol contents of developed rice Jochung were 56.4%T and 108.23 mg GAE/100 g, respectively. The adhesiveness values of various commercial-rice Jochung products were 29.0~66.0 sec, while that of developed-rice Jochung was 61 sec, showing good textural properties for use in manufacturing Hangwa, a Korean traditional cookie. The electron-donating values of various rice Jochung were 20.4~50.3%, among which the developed-rice Jochung showed the highest value. The reducing powers of various rice Jochung products were 0.44~0.72, while that of the developed product was 0.72, which was significantly higher than the other values. Sensory evaluation revealed that the color scores of developed- and commercial-rice Jochung products were 6.70~6.80. Flavor scores of rice Jochung products ranged from 6.00 to 7.00. Taste and mouth feeling scores of developed-rice Jochung did not significantly differ from those of commercial Jochung products. Compared to commercial-rice Jochung products, developed-rice Jochung made with malt extract exhibited high polyphenols content. However, there were no significant differences in the overall acceptability scores between commercial-rice Jochung products and the developed product. The developed-rice Jochung analyzed in this study may be useful as a traditional sweetener for various Hangwa products as a substitute for corn syrup or Jochung.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.199-215
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• 1998

In order to determine the effect of tomato(Lycopersicon escylentnm mill ssp.) on the yogurt quality, skim milk powders were added with tomato juice of 0%, 1%, 3%, 5% and fermented by mixed culture(Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. The results were summarized as follows: 1. Addition of tomato juice in skim milk decreased pH(4.3) and increased acidity(0.93%) more than control did(pH 4.6, titratable acidity 0.85%). By the addition of tomato juice, acid production was increased and pH was decreased in proportion to concentrations of tomato juices added to skim milk. 2. The number of lactic acid bacteria in yogurts added with tomato juice ($4.59{\times}10^{12}cfu/ml$) more increased than those in control yogurt($8.96{\times}10^{11}cfu/ml$). By the addition of tomato juice, the number of lactic acid bacteria counts increased in proportion to concentration of tomato juices added to skim milk. 3. As fermentation time goes by, the Brix degree sugar content in skim milk were decreased more rapidly than control. 4. The pH, titratable acidity, Brix degree and lactic acid bacteria were not significantly changed for all yogurts for the storing at $5^{\circ}C$ for 14 days. 5. In yogurt fermentation, addition of tomato juice with glucose (1% tomato juice + 4% glucose, 3% tomato juice + 2% glucose, 5% tomato juice + 0% glucose) decreased pH and increased acidity than control(5%glucose) did. In addition of tomato juice, acidity was increased and pH was decreased in proportion to concentration of tomato juices added to skim milk. 6. In yogurt fermentation, the number of lactic acid bacteria of yogurt added with tomato juice(1% tomato juice+4% glucose, 3% tomato juice+2% glucose, 5% tomato juice+0% glucose) increased than control(5% glucose). In addition of tomato juice, the number of lactic acid bacteria increased in proportion to concentration of tomato juices added to skim milk. 7. As fermentation time goes by, the Brix degree were decreased more rapidly than control(5% glucose). By the change of pH, titratable acidity, Brix degree and lactic acid bacteria, in yogurt fermentation, we definited that the promotive effect of tomato(Lycopersicon escylentnm mill ssp.) on the yogurt.