• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.307-313
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• 2013

This study was carried out to investigate the residual characteristics of fungicide azoxystrobin and difenoconazole in Prunus mume fruits, and establish pre-harvest residue limits (PHRL) based on dissipation and biological half-lives of fungicide residues. The fungicides were sprayed onto the crop at recommended dosage once and 3 times in 7 days interval, respectively. The samples were harvested at 0, 1, 2, 4, 6, 8, 10, 12 and 14 days after treatment. These residual pesticides were extracted with QuEChERS method, clean-up with $NH_2$ SPE cartridge, and residues were analyzed by HPLC/DAD and GLC/ECD, respectively. Method quantitative limits (MQL) of azoxystrobin were 0.03 mg $kg^{-1}$ and of difenoconazole were 0.006 mg $kg^{-1}$. Average recovery were $93.2{\pm}2.49%$, $85.5{\pm}1.97%$ for azoxystrobin at fortification levels at 0.3 and 1.5 mg $kg^{-1}$, and $100.8{\pm}6.74%$, $87.6{\pm}9.92%$ for difenoconazole at fortification levels at 0.06 and 0.3 mg $kg^{-1}$, respectively. The biological half-lives of azoxystrobin were 5.9 and 5.2 days at recommended dosage once and 3 times in 7 days interval, respectively. The biological half-lives of difenoconazole were 9.3 and 8.0 days at recommended dosage once and 3 times in 7 days interval, respectively. The PHRL of azoxystrobin and difenoconazole were recommended as 5.32 and 1.64 mg $kg^{-1}$ for 10 days before harvest, respectively.

• Food Science and Preservation
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• v.13 no.4
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• pp.432-437
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• 2006

To compare the content of natural existence with artificial addition experimental subject of 152 cases(25 kinds) were classified by two category of 42 fresh samples(14 kinds) and 110 processed samples(23 kinds). The content of sulfur dioxide were determined by Monnier-Williams's modified method. In mean content of 42 non-processed samples studied the range of contents was between 0.00 and 9.46 mg/kg. Radish contained the highest amount of sulfur dioxide(8.97 mg/kg), followed by onion(8.04 mg/kg). In mean content of 110 processed samples studied, the range of content was between 0.00 and 1,828.59 mg/kg. Gourd contained the highest amount of sulfur dioxide(1,064.61 mg/kg), followed by apricot(869.62 mg/kg), dried persimmon(64.11 mg/kg), dried radish(29.00 mg/kg), dried pumpkin(17.63 mg/kg), and those were lowe. than criteria. To supply safe food for the citizens, the quantitative level is required to be reinforced to supply safe foot continuously.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.361-372
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• 2017

Bred and grown around the world, tomato (Solanum spp.) has highly valuable fruits containings various anti-oxidants such as lycopene, flavonoids, glutamine, and ${\beta}-carotene$. Several studies have explored, way in which to enhance the growth, management and quality of tomato, we focus on the management of growth for yield rather than quality. The expression of superior agronomic traits depends on where cultivars are grown. We evaluated 10 cultivars grown in three environment for their lycopene. HTL3137 ($70.48mg{\cdot}kg^{-1}$), which was grown in Yoeju in spring/summer, contained the highest lycopene content, while HTL10256 ($20.9mg{\cdot}kg^{-1}$), which was grown in Suwon in spring/summer, contain the least lycopene.Correlations between color components and lycopene content varied according to growing location and season. In spring/summer-grown tomatoes from Suwon, no significant correlation was observed between any color component (redness [R], greenness [G], blueness [B], luminosity, $L^*$, $a^*$, $b^*$, hue and chroma) and lycopene content. A correlation was observed between B and lycopene content in tomatoes grown in Yeoju during the same season. In tomatoes grown in Yeoju in fall/winter, significant correlations were found between lycopene content and G, luminosity, $L^*$, and hue. Variance in interactions between genotype, environment, and genotype ${\times}$ environment (G ${\times}$ E) using Minimum Norm Quadratic Unbiased Estimate (MINQUE) analysis indicated that lycopene content depends on genotype (51.33%), environment (49.13%), and G ${\times}$ E (21.43%). However, when the Additive Main Effects and Multiplicative Interaction (AMMI) was used, the G ${\times}$ E value was highest.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.409-413
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• 2004

We have studied quality changes of fully ripe fruit of Korean native pumpkin 'Yangsan' regarding the following parameters: pH, sugar content, weight, water content, contents of crude protein and amino acids during 60 days storage at room temperature. As the results, there was no changes in sugar contents according to the storage period, but pH was changing to a little acidic direction with slight decrease in weight and water content. Contents of total crude proteins and comprising amino acids were increased during the storage period. The main contents of amino acids of the Korean native pumpkin, Yangsan, were glutamic acid (15.5%), aspartic acid (10.1%), lysine (8.7%), valine (7.5%), leucine (7.1%) and alanine (6.6%), which were not highly influenced during storage period. Additionally we have investigated the content of free amino acids and color changes during processing of Yangsan under high temperature at $121^{\circ}C$ and high pressure at $1\;kg/cm^2$. In fully ripe fruits, a total of 29 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 35% of total free amino acids were aspartic acid (20.3%) and asparagine (15.4%); ornithine, citrullin, and arginine, which are related to Ornithine cycle, were also detected in fully ripe fruits. But when treated with high temperature and high pressure, glutamic acid and arginine were decreased rapidly whereas ammnonium chloride was relatively increased. Moreover "b" value as yellow color indicator was decreased from 17.45 to 9.14 while treated for 60 minutes with high temperature and pressure, caused by the degradation of ${\beta}-carotene$ and other yellowish pigments in Yangsan.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1467-1475
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• 2010

Nutritional and functional components, and physicochemical characteristics of mulberry fruits from Morus alba L. cultivars, including Daejappong, Iksuppong, Daesungppong, Yongppong, Cheongilppong, Gwasang 1 and Gwasang 2, were investigated and compared. Among the 7 mulberry cultivars examined, Iksuppong, Cheongilppong and Gwasang 2 had higher contents of nitrogen free extract, total sugar and total reducing sugar, than other mulberry cultivars, while contents of protein, fat, and fiber were lowest. Gwasang 1 and Daesungppong had the highest content of total phenolic, total flavonoid, and total anthocyanin. Daesungppong, Gwasang 1 and Gwasang 2 had higher contents of C3G and C3R than other mulberry cultivars, although C3R content of Cheongilppong was the highest. Four flavonoid contents varied among of 7 mulberry cultivars. Contents of two major flavonoids, rutin and quercetin, were the highest in Gwasang 2, while Iksuppong and Cheongilppong were the lowest. Contents of piceid and 4-prenylmoracin were the highest in Daesungppong and Cheongilppong, respectively. Cheongilppong of mulberrys had the highest content of GABA. Iksuppong and Gwasang 2 with moderate weight and dark color had higher contents of total soluble solid than other mulberry cultivars, while contents of titratable acidity were lower. Our results provide useful information on nutritional and functional constituents of mulberry fruits according to cultivars, and their physicochemical and processing properties.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.37-44
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• 2001

The biological effects of the iminoctadine tris (albesilate) and kresoxim-methyl for the protection of citrus postharvest diseases caused by penicillium spp. were assayed. In vitro tests, $EC_{50}$ values of iminoctadine tris(albesilate) were $0.01{\sim}0.02\;and\;0.01{\mu}g$ a.i./mL against mycelial growth of P. italicum and P. digitatum, respectively, but iminoctadine tris(albesilate) at $0.64{\mu}g$ a.i. /mL inhibited a little mycelial growth of unknown Penicillium sp. which produced another symptom different to blue and green mold caused by P. italicum and P. digitatum, respectively. And against germination and growth of germ tube of P. italicum and P. digitatum, $EC_{50}$ value of iminoctadine tris(albesilate) was $0.0013{\sim}0.0025{\mu}g$ a.i./mL. But spore germination of unknown Penicillium spp. was not nearly inhibited at $0.2{\mu}g$ a.i./mL. $EC_{50}$ values of kresoxim-methyl were $0.08{\sim}0.16$, 0.04 and $0.16{\mu}g$ a.i./mL against mycelial growth of P. italicum, P. digitatum and unknown Penicillium sp., respectively, and $0.04{\sim}0.08{\mu}g$ a.i./mL and $0.01{\sim}0.02{\mu}g$ a.i./mL against germination and growth of germ tube of P. italicum and unknown Penicillium sp., and P. digitatum, respectively. Iminoctadine tris(albesilate) and kresoxim-methyl were markedly effective to control the postharvest disease by 7 days spray prior to harvest. When the fruits were sprayed with iminoctadine-tris(albesilate) ($200{\mu}g$ a.i./mL) and kresoxim-methyl ($155{\mu}g$ a.i./mL) 7 days prior to harvest and subsequently stored for 90 days, the percentage of diseased fruit by Penicillium spp. was $3.6{\pm}1.8%$ in treatment of kresoxim-methyl and $5.9{\pm}1.8%$ in iminoctadine-tris(albesilate), respectively. On the other hand, tile percentage of diseased fruit was relatively high, $20.3{\pm}10.0%\;and\;19.5{\pm}9.6%$ in thiophanate-methyl ($700{\mu}g$ a.i./mL) and non-treatment, respectively. Maximum residue amount (ppm) among fruits (flesh and peel) assayed 0, 30, 60 and 90 days after storage was 0.45 and 0.10 ppm in treatment of kresoxim-methyl and iminoctadine, respectively.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.93-102
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• 2016

This research was conducted for major cultivated chestnut (Castanea spp.) in Korea to compare chestnut quality characteristics according to storage temperatures ($4^{\circ}C$ vs. $-1^{\circ}C$) and cultivars. Color, hardness, soluble solids content (SSC), rate of decay and sensory evaluation were investigated during 16 weeks storage. Cultivars 'Tsukuba' and 'Ishizuchi' showed the least pericarp color change while cultivars 'Riheiguri' and 'Daebo' showed the most pericarp color change during storage. Chestnut fruits stored at $-1^{\circ}C$ showed less pericarp color change than those stored at $4^{\circ}C$. Cultivars 'Arima' and 'Tanzawa' exhibited the decrease tendency of hardness with lowest hardness during storage at $-1^{\circ}C$. Chestnut fruits stored at $4^{\circ}C$ showed high hardness than those stored at $-1^{\circ}C$. Cultivars 'Riheiguri' showed the highest increase of SSC, while cultivar 'Arima' showed the lowest increase of SSC after 16 weeks of storage. The SSC increased in nuts from all cultivars at both temperatures, but nuts stored at $-1^{\circ}C$ showed higher increases in SSC than nuts stored at $4^{\circ}C$. Cultivars 'Ishizuchi' and 'Riheiguri' showed high rates of decayed nuts in contrast to cultivars 'Daebo', 'Okkwang' and 'Tanzawa' that showed low rates of decayed nuts during storage. The chestnut fruit stored at $-1^{\circ}C$ showed less decay than fruit stored at $4^{\circ}C$. Texture and sweetness were tested for sensory evaluation. Among the tested cultivars, 'Riheiguri', 'Daebo' and 'Tsukuba' showed hard texture and very sweetness, while 'Tanzawa' showed relatively soft texture. 'Arima' and 'Okkwang' showed weak sweetness during storage. Nuts stored at $4^{\circ}C$ exhibited harder texture than nuts stored at $-1^{\circ}C$ while $-1^{\circ}C$ exhibited more sweetness than nuts stored at $4^{\circ}C$. Chestnuts for hard texture and short-term storage (less than one month), $4^{\circ}C$ will be a proper storage temperature, while in order to store long-term (more than 4 month), $-1^{\circ}C$ will be a proper storage temperature. Result from this study provide base-line data of postharvest management for Korean cultivated chestnut as well as contributing increased product value and income for chestnut producers.

• Journal of Nutrition and Health
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• v.48 no.1
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• pp.81-93
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• 2015

Purpose: The aim of this study was to estimate total sugar intake and sugar intake-related dietary habit and nutrient intake of elementary school students. Methods: Subjects included 701 elementary school students (351 boys and 350 girls) residing in Jeju. The research analyzed a sample and was carried out using the 24 hour recall method and one day consumption of total sugar. Results: The average daily total sugar intake was 55.3 g (male 53.1 g, female 57.6 g). Total sugar intake per meal was 6.3 g (11.4%) from breakfast, 6.9 g (12.5%) from lunch, and 7.2 g (13.0%) from dinner, 34.9 g (63.1%). Major food groups of total sugar were milks (17.04 g), grains and their products (12.79 g), fruits and their products (9.40 g), and sugars and sweets (7.30 g). In analysis of the amount of total sugar consumption from several recipes, much was taken in from dessert and snacks such as dairy products (15.08 g), bread and snacks (6.4 g), beverages (5.5 g), fruits (5.1 g), and ice cakes (4.8 g). Total sugar consumption was high for rices and side dishes such as noodles (5.1 g), stir-fried foods (2.3 g), fried foods (1.4 g), cooked rice with seasoning (1.4 g), and hard-boiled foods (1.1 g). In comparison of total sugar consumption for sugar sources, daily intake of natural sugar, added sugar, and natural and added sugar were 25.8 g, 23.3 g, and 6.2 g, respectively. High sugar intake group, which was over 20% of the energy from total sugar intakes, consumed significantly less Fe, Zn, and niacin than the low sugar intake group, which was below 20%. Conclusion: Total sugar intake of fifth graders of elementary schools on Jeju Island was 55.4 g/day, and it was usually intake from snacks. Therefore, elementary school students need nutritional education for proper selection of better snacks and for reduction of dietary sugar intake.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1523-1528
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• 1999

The consumer's demands for minimally processed fruits and vegetables have been increased rapidly because of its convenient handling, fresh-like quality as well as producing less wastes from the environmental point of view. Asian pears which are one of the main fruits widely produced and consumed in Korea easily lost their characteristics due to browning and softening after cutting. The objective of this study is to investigate the effects of various treatments on delaying deterioration of sliced Asian pears. 'Shingo' pear slices were treated with various solutions $(1%\;NaCl,\;0.2%\;L-cysteine,\;1%\;CaCl_2\;or\;1%\;calcium\;lactate)$ and were packaged with low density polyethylene $(LDPE,\;60\;{\mu}m)$, ceramic $(CE,\;60\;{\mu}m)$ or vacuum $(Ny/PE,\;80\;{\mu}m)$ film at $20^{\circ}C\;and\;0^{\circ}C$. In order to evaluate the quality of packaged sliced pears, quality index was determined in terms of color, firmness, soluble solids, titratable acidity. ascorbic acid, changes of gas composition, microbial test, and sensory quality. The results showed that sliced 'Shingo' pears packaged with CE and vacuum film maintained better quality than with LDPE at $0^{\circ}C\;and\;20^{\circ}C$. To retard browning and softening. 0.2% L-cysteine and 1% NaCl solutions applied for 1 minute were effective to reduce surface browning of sliced pears, and 1% $CaCl_2$ was the most effective to prevent softening.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.413-420
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• 2019

In this study, a sample preparation method and a simultaneous determination method by ultra-high performance liquid chromatography coupled with tandem mass spectrometry for 9 isomers of chlorogenic acid and arbutin in fruits were developed. The samples were extracted using 90% methanol (pH 3.0), with the solutions being shaken and then sonicated for 10 min each. After centrifugation at 4,000 rpm for 10 min, the extraction was concentrated under a vacuum at $40^{\circ}C$ using a vacuum evaporator. The residue was dissolved in 5 mL of 5% methanol and filtered through a $0.45{\mu}m$ membrane before UHPLC-MS/MS analysis. The separations were performed on a C18 column with gradient elution of water (containing 0.1% formic acid) and methanol (containing 0.1% formic acid). The specificity, linearity, limit of detection, limit of quantification, accuracy, and precision of the proposed methods were also evaluated.