• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.401-416
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• 2011

The recent trend for pesticide residue analysis in food involves fast cleanup and use of mass spectrometry to achieve quantitative and qualitative analysis at the same time. Recently, the QuEChERS (quick, easy, cheap, effective, rugged and safe) multi-reside method has received much attention as a fast extraction and cleanup method of pesticide residue analysis. Therefore, multi-residue analysis of 236 pesticides was tested with the QuEChERS method by concurrent use of PTV-GC/TOFMS (gas chromatography/ time-of-flight mass spectrometry with programmable temperature vaporizer). PTV condition was optimized and when the method was applied to apples, pesticide recovery rates (spiked at 400 ng/g) ranged from 80% to 120%, and RSD values were under 10% for most compounds. The results showed that the QuEChERS sample preparation and PTV-GC/TOFMS analysis can be applied to multi-residue analysis of pesticides in fruits and vegetables.

• Food Science and Preservation
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• v.16 no.1
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• pp.122-127
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• 2009

This study was to separate wild yeast from the Houttuynia Cordata Thunb(HC) extracts fermented in traditional way and investigate the characteristics of fermentation from the HC extracts. As a result, the longer the cultivation time, the more the contents of alcohol in $15^{\circ}Brix$ sugar solutions increased. When it reached to 90 hours since it cultivated, it ranked HCE 12%, HCD 11.2%, and HCA 10.5% in order. As for HCF, HCG, HCB, and HCC), this study has shown that the contents of alcohol were from 7.5% through 8.5%. As a result of selecting germ strains like HCE and HCD with the highest alcohol-genicity in the sugar solutions as separated yeast from HC and of comparing and reviewing the existing Saccharomyces germ strains and fermentation power in the medium of HC(Juice extraction of HC : Distilled water(1:1), this study has found out that 'pH' decreased from $4.09{\sim}4.12$ before fermentation through $3.57{\sim}3.78$ after fermentation. And, the sugar concentration decreased from $15.00{\sim}15.19^{\circ}Brix$ through $7.75{\sim}9.57^{\circ}Brix$ before fermentation. Also, the acid value increased from $0.138{\sim}0.210%$ before fermentation through $0.282{\sim}0.45%$ after fermentation. In addition, as the contents of alcohol became $3.6{\sim}4.6%$ after fermentation, isolates HCD and HCE from HC had higher value rather than ones of DJ97, YJK, R12, and RCY separated from persimmons, apples, and grapes. The result value of color was minimum $4.75{\pm}1.44$ and maximum $6.85{\pm}1.63$, and HCE marked the highest record among the items of sensory evaluation. The overall acceptability was in normal level like minimum $3.95{\pm}1.17$ and maximum $5.00{\pm}1.41$. It is considered as it could lower sensory evaluation because the acceptability of flavor was not satisfied. After all, the significance(p<0.05) among the germ strains was not recognized in aspects of color, flagrance, flavor, and overall acceptability.

• Culinary science and hospitality research
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• v.17 no.1
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• pp.142-154
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• 2011

The purpose of this research is to examine the awareness and preference for a variety of Kimchi and Kimchi intake patterns among the students living in Chungbuk province. Four hundred samples, consisting of elementary, middle, and high school students, were surveyed; and a total of 366 usable, completed copies of the questionnaire were used for the research. The collected data were statistically analyzed using SPSS 10.0. The results of the analysis were as follows: First, Kimchi was considered traditional (24.3%), nutritious (20.5%), fermented (l9.2%), and healthy (16.1%). Second, the main reason Kimchi was preferred was its "hot taste" (25.4%), "chewy texture" (17.4%), and "sour taste" (14.0%). The students preferred their Kimchi a little hot, moderately salty, and properly fermented with a moderate amount of seasoning and did not care much about any particular parts of Kimchi. Third, 75.4% of the students ate Kimchi more than twice a day, and 78.0% of the students consumed more than 3 pieces($2.5{\times}3.0cm$) of Kimchi per meal. Fourth, elementary students wanted the school foodservice to develop bite-sized Kimchi while middle school students wanted to eat their favorite parts of Kimchi without the fishy smell. High school students wanted to eat cool and fresh Kimchi. Finally, the students wanted Kimchi to contain the following fruit and vegetables: pears (48.9%), apples (34.2%), and pineapples (30.0%), young radishes (44.9%), turnips (37.5%), and sesame leaves (34.9%). This study concludes that it is necessary to educate young students about traditional Korean food culture, serve them various types of Kimchi, change the service style, and develop new Kimchi recipes to increase Kimchi intake in school foodservices.

• Food Science and Preservation
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• v.15 no.1
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• pp.15-20
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• 2008

By considering the storage temperatures of agricultural products, three types of PCMs $(K_1$, $K_2$, $K_3$) were developed to be used in temperature ranges of $0{\sim}5^{\circ}C$, $5{\sim}10^{\circ}C$ and $10{\sim}15^{\circ}C$, $K_1$ PCM for $0{\sim}5^{\circ}C$ was developed by mixture of $C_{14}H_{30}$ and soduim polyacrylate, and $K_2$ PCM for $5{\sim}10^{\circ}C$ and $K_3$ PCM for $10{\sim}15^{\circ}C$ were mixture of $C_{14}H_{30}$, $C_{18}H_{38}$ and soduim polyacrylate with different composition ratio. 'The target temperatures of cold chain system were set at $7^{\circ}C$, $13^{\circ}C$, and $17^{\circ}C$ with $K_{1-3}$, $K_{2-3}$ and $K_{3-1}$ PCMs, respectively. The times to reach the target temperatures in the storage chamber were 21 hours, 18 hours, and 61 hours with $K_1$, $K_2$, and $K_3$ PCMs, respectively. The performances of natural convection type and forced convection of the temperature controlled portable container were analyzed Apples were stored in the portable container of $5^{\circ}C$, and temperatures at surface and center were measured. The initial temperature of the apple was $25^{\circ}C$. The temperatures of apple at the surface and the center were $15^{\circ}C$ and $16^{\circ}C$, respectively, after 5 hours with natural convection type. However, the temperatures at the surface and the center were already reached to $7^{\circ}C$ within 1 hour with forced convection type. The forced convection type showed the better performance and the temperatures of portable container were maintained more than 15 hours.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.28-36
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• 2018

Studies on suspected endocrine disrupting pesticide (EDP) residues in agricultural products were carried out in 2016 in Busan, Korea. Twelve different EDPs, ranging in concentration between 0.003-2.049 mg/kg, were detected in 19.5% of 462 samples. About 0.2% of agricultural product samples exceeded the maximum residue limits (MRLs). Risk indices of all of the EDPs were less than 10% of the acceptable daily intake (ADI). The outcomes indicated that the risk groups at highest risk of exposure to diazinon (found in Korean cabbages) and carbendazim (found in apples) were females aged 40 to 49 and young males less than 10 years old, respectively. Based on the stochastic assessment at $95^{th}$ percentile (P95), risk index in these risk groups accounted for 8.38 and 2.98% of ADIs. The results showed that the occurrence of EDP residues in agricultural products could not be considered a public health problem.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.165-173
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• 2003

This study was carried out to develop a better fruit-dressing than previous mayonnaise in terms of calories, salt content and color, using kiwis, oranges, strawberries, and apples. This study was aimed to identify the perception, physico-chemical and sensory characteristics of the 4-kinds of fruits dressing. The results were as follows: The perception of the fruit dressings received the highest score (3.90) for 'It's convenience foods'. The misture in the dressings ranged from 49.3 to 59.4%, and was highest in apple dressing, followed by the kiwi, strawberry, and orange dressings, in that order. The crude ash for the dressings ranged from 0.8 to 1.4%, and was highest in the orange dressing. The L value was highest in the apple dressing, the a(-) value in the kiwi dressing, the a(＋) value in the strawberry dressing and the b value in the orange dressing. The Ca/ P ratio was about 1.17 : 1. The results of mineral contents analyses were also examined. The calcium, magnesium and potassium levels were highest in the orange dressing. The mineral contents of fruit dressings were 6.7 to 20.4mg/100g for calcium, 6.5 to 20.5mg/100g for magnesium and 67.2 to 182.6mg/100g for potassium. The sodium content of the fruit dressings were lower than in the previous mayonnaise, especially for the kiwi-dressing, which was 30% that in the mayonnaise. As a result of the sensory evaluations of the 4-kinds of fruits dressing, the kiwi dressing received the highest scores (3.50) of all the fruit-dressings in relation to the taste and palatability. Fruit are good for producing dressings that are low in calories and salt, with kiwi dressing proving to be the best of those fruits tested.

• Journal of Plant Biotechnology
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• v.46 no.3
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• pp.228-235
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• 2019

Apple (Malus pumila) is one of the most economically important fruits in Korea. but virus infection has decreased the sustainable production of apples and caused serious problems such as yield loss and poor fruit quality. Virus or viroid infection including apple chlorotic leaf spot virus (ACLSV), apple stem pitting virus (ASPV), apple stem grooving virus (ASGV), apple mosaic virus (ApMV) and apple scar skin viroid (ASSVd) have been also reported in Korea. In many cases, as apple gets infected with virus and viroid with no specific symptoms, the damage and symptoms caused by the viruses are not detected. In our research, viruses in the rootstock were eliminated for a virus-free apple dwarfing rootstock of M.9 and M.26. The virus elimination methods were apical meristem culture, thermotherapy ($37^{\circ}C$, 6 weeks) and chemotherapy($Ribavirin^{(R)}$). The detection of apple viruses was accomplished by Enzyme-linked Immuno-Sorbent Assay (ELlSA) and reverse transcription-polymerase chain reaction (RT-PCR). RT- PCR method was 10 ~ 30% more sensitive than the ELISA method. The efficiency of virus elimination was enhanced in apical meristem culture method. The acquisition rate of virus-free apple dwarfing rootstocks was 30 ~ 40% higher in apical meristem culture. After the meristem culturing of M.9, the infection ratio of ACLSV, ASPV and ASGV was 45%, 60% and 50%, respectively. In the apple dwarfing rootstock of M.26, the infection ratio of ACLSV, ASPV and ASGV was 40%, 55% and 55%, respectively. Based on this study, the best method for the production of virus-free apple dwarfing rootstocks was the apical meristem culture.

• Journal of Nutrition and Health
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• v.54 no.1
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• pp.10-22
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• 2021

Purpose: Key Foods refers to foods that have a high contribution in the nutrient intake of individuals, and exert important effects on their health. This study was undertaken to identify Korean Key Foods, using data from the 7th Korea National Health and Nutrition Examination Survey (KNHNES). Methods: The data source for the extraction of Key Foods was the 24-hour dietary survey data obtained from the 7th KNHNES (2016-2018), and 21,271 subjects were evaluated. A total of 17 nutrients were selected as the key nutrients for identifying the Key Foods, including energy, carbohydrates, protein, lipid, dietary fiber, calcium, phosphorus, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, vitamin C, cholesterol, and sugars. The nutrient consumption approach was applied to generate a list of potential Key Foods. Foods included in 85% of the cumulative intake contribution from one or more key nutrients, were subsequently selected as Key Foods. Results: Of the 1,728 foods consumed by survey respondents, we extracted 728 Key Foods. These Key Foods explained 94% key nutrient intakes of the subjects. Based on the contribution rate to key nutrient intake, the top 10 Key Foods identified were multigrain rice (5.32%), plain white rice (4.23%), milk (3.3%), cabbage kimchi (2.82%), grilled pork belly (1.56%), apples (1.52%), fried eggs (1.49%), cereal (1.36%), instant coffee mix (1.21%), and sweet potatoes (1.12%). These 10 foods accounted for 23.93% total key nutrient intake of the survey respondents. Conclusion: Seven hundred and twenty-eight foods were extracted and identified as the 2020 Korean Key Foods. These Key Foods can be considered the priority foods to be analyzed for establishing a national nutrient database.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.131-139
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• 2023

In this study, we investigated pesticide residue levels in 535 domestically distributed agricultural products in South Korea using multi-residue analysis. Agricultural products from 13 regions, including Seoul, were pretreated using QuEChERS and d-SPE, and subsequently analyzed using LC-MS/MS and GC-MS/MS. Residual pesticides were detected in 288 (53.8%) out of the 535 samples, including 40 of apples, 40 of peppers, 33 of mandarins, 31 of peaches, and 144 other commodities. Furthermore, one sample of Korean cabbage exceeded the permitted maximum residue limit (MRL), diniconazole (0.18 mg/kg), detected at about twice the MRL. In total, 91 types of residual pesticides were detected, including fungicides (42), insecticides (48), and a nematicide. The most frequently detected pesticides were dinotefuran (91), carbendazim (75), tebuconazole (61), and pyraclostrobin (59). Our results showed that continuous monitoring of agricultural products is necessary.

• Journal of Practical Agriculture & Fisheries Research
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• v.18 no.1
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• pp.79-91
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• 2016

Quality factors which characterize 11 kinds of farm-manufactured apple Jangachi and commercial Jangachi, have been studied in order to provide a guideline to improve the quality and marketing strategy of farm-manufactured pickled apples. Moisture content ranged from 74% to 84% and 81% to 91% in Doenjang Jangachi and vinegar Jangachi, respectively; 38% to 64% in Kochujang Jangachi; 57% to 64% in radish Kochujang Jangachi. Moisture content was 89% in Doenjang Jangachi. Even though moisture content of apple Kochujang Jangachi indicated 48% which is lower than that of radish Jangachi, it was higher than that of a persimmon pickled in Kochujang (38%) and that of Japanese apricot Jangachi (49%). pH and titratable acidity, two indicators used to determine the appropriate ripening period of Jangachi, were pH 3.4~5.6, 0.03~0.14%, respectively. The pH ranged from 5.2 to 5.6 in radish Jangachi; 3.4 to 4.1 in Cucumber Jangachi. pH of persimmon Jangachi, Japanese apricot Jangachi and apple Jangachi showed 4.1, 3.5 and 4.1, respectively. Compared with the pH of traditional Jangachi (3.03~5.36), pH of all of the above Jangachi fall into an appropriate range. The brix of apple Jangachi (30%) was 12% to 18% higher than that of Kochujang radish Jangachi, but it was relatively lower than that of persimmon Jangachi (39%) and that of Japanese apricot Jangachi (49%). Salinity of Jangachi varied depending on which marinating material was used. Salinity in the descending order according to each marinating material demonstrated Kanjang (6% to 13%), Doenjang (7%), Kochujang (3% to 4%). Salinity of apple Jangachi was 3.28% which was relatively lower than that of commercial Jangachi which used either Kanjang or Doenjang as its marinating material. Chromaticity test shows that the brightness value of apple Jangachi (54.70) was similar to that of cucumber Jangachi (50.86, 56.02); the redness value and yellowness of apple Jangachi (16.21 and 26.78) were higher than the redness value (7.27 to 11.23) and the yellowness value (10.62 to 14.69) of radish Kochujang Jangachi. Sensory Characteristics value of apple Jangachi, along with radish and cucumber Jangachi in its color, odor and taste (7.00, 7.50, 7.00, respectively) placed high on the list implying higher preference. However, overall preference value of apple Jangachi was 6.83 which was lower than that of Japanese apricot Jangachi or that of radish Jangachi. The result can be explained by the tendency of people preferring crispy Jangachi and points out that the texture of apple Jangachi needs to be improved to gain popularity. Furthermore, for increased sales of apple Jangachi as a niche product, more rigorous market testing is required.