• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1358-1365
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• 2016

The purpose of this study was to verify the drying characteristics of seasoned red pepper sauce and establish optimal drying conditions for far infrared drying of seasoned red pepper sauce. Seasoned red pepper sauce, which was dried by heated air, was used. One kg of seasoned red pepper was spread at thicknesses of 10 and 20 mm and dried by a far infrared dryer until a final moisture content of $15{\pm}0.5%$. The far infrared dryer conditions were air velocity of 0.6, 0.8 m/s and drying temperatures of 60, 70, and $80^{\circ}C$. The drying models were estimated using a determination coefficient and root mean square error. Drying characteristics were analyzed based on factors such as drying rate, color changes, content of capsaicinoids, and energy consumption. The results can be summarized as follows. The drying rate (that is, drying time) tended to be reduced as temperature and air velocity for drying increased. The Page and Henderson models were suitable for drying of seasoned red pepper sauce by a far infrared dryer. Redness decreased after far infrared drying under all experimental conditions. The color difference was 18.18 under the following conditions: thickness 20 mm, temperature $70^{\circ}C$, and air velocity 0.8 m/s. This value was slightly higher than those under other far infrared drying conditions. The capsaicinoid properties of seasoned red pepper sauce decreased under all far infrared drying conditions. The highest capsaicin (19.91 mg/100 g) and dihydrocapsaicin (12.87 mg/100 g) contents were observed at a thickness of 10 mm, temperature of $80^{\circ}C$, and air velocity of 0.8 m/s. Energy consumption decreased with higher temperature, slower air velocity, and thinner seasoned red pepper sauce.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.283-288
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• 2010

Yam (Dioscorea spp.) has been used as important edible and medicinal natural resource in worldwide and D. alata L. is most popular nourishment among the yam. In this study the composition, color, antioxidation and antimicrobial activity of D. alata Gyeongbuk No. 6 (GB-6), which was established in Gyeongbuk Agricultural Research & Extension Services, Andong, Korea, was compared to those of D. batatas Gyeongbuk No. 1 (GB-1), a major domestic cultivation species. Water content of GB-6 was $78.02{\pm}0.16%$, which is slightly lower than that of GB-1 ($82.6{\pm}0.07%$). The contents of crude protein, crude fat, crude fiber and ash of GB-6 were 0.95, 0.26, 0.85 and 0.70%, whereas those of GB-1 were 1.58, 0.15, 1.39 and 0.88%, respectively. Analysis of color using colormeter showed that the GB-6 is slight dark-yellow than GB-1, and total polyphenol content of GB-6 was 2-fold higher compared than that of GB-1. Sequential organic solvent fractions from methanol extract of GB-6 showed that the ethylacetate fraction has highest total polyphenol ($144.1{\pm}3.20\;mg/g$). Determination of antioxidation activity showed that the ethylacete fraction and water fraction has strong DPPH radical scavenging activity ($IC_{50}=78.32\;{\mu}g/mL$) and reducing power, respectively. In antimicrobial activity assay, the n-hexane and ethylacetate fraction showed antibacterial activity against B. subtilis, L.monocytogenes, S. epidermidis, S. aureus, P. vulgaris, and S. typhimurium. These results provide the possibility of domestic cultivated D. alata GB-6 as a healthy food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1082-1090
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• 2005

Jocheong was prepared by adding Lentinus edodes extract to improve its quality and to give some functional properties. Contents of crude protein, ash and crude lipid were similar to those of control, while carbohydrate content was decreased. Total mineral content were $1,916.03\~2,674.24mg/kg$ that was no difference between test samples. From HPLC determination of free sugars, Jocheong was found to contain maltose as the highest sugar, followed by glucose and fructose. In amino acid analysis, seventeen amino acid were identified and quantified. Glutamic acid in Jocheong was major amino acid. The major fatty acids in Jocheong $(0\%,\;control)$ were linoleic acid, palmitic acid, oleic acid, myristic acid and caproic acid. There was no significant differences in fatty acid composition, pH and reducing sugar content among the Jocheong samples. The viscosity and solid contents tended to decrease with the addition of Lentinus edodes extract. Increasing the ratio of mushroom extract in Jocheong tended to decrease the lightness, yellowness and redness in Hunter's color value. Although sensory value decreased with increasing Lentinus edodes extracts, use of mushroom extracts (7: 3; saccharification liquids: Lentinus edodes extracts) is recommended for making Jocheong.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.687-696
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• 2015

Black mini tomato 'Hei-G' fruits were harvested at different stages of maturity (immature-mature green and mature-black red) and stored at different temperatures (8, 12, and $20^{\circ}C$) to investigate the quality and lycopene content during storage. Weight loss increased dramatically at higher temperature for both harvesting stages without significant differences. Firmness of immature fruits decreased below the initial level of mature fruit (8.1N) after 5, 8, and 19 days storage, when they were stored at 20, 12, and $8^{\circ}C$, respectively. Soluble solid contents of mature fruit increased at initial storage, and were higher as compared to immature fruits before deterioration at each storage temperature. Decrease in titratable acid of mature fruits depended on storage time and temperature. However, titratable acid of immature fruits showed little change during storage, and so it did not affect flavor. Hunter a value changed greatly in immature fruit stored at high temperature. Unlike ripe tomatoes, there was no significant difference in black tomato Hunter b values of immature and mature fruit at initial and 12 days storage. However, immature fruits stored at $8^{\circ}C$ did not reach full maturity and color development and ripening. High storage temperature increased lycopene production while low storage temperature blocked lycopene development. Shelf life of the immature fruits, which was evaluated by elapsed days to conventional mature stage, was 12 and 15 days when they were stored at 20 and $12^{\circ}C$, respectively. The optimum storage temperature to maintain the quality and lycopene content of mature fruits was $12^{\circ}C$. Moreover, the shelf life of mature fruits stored at $20^{\circ}C$ could reach up to 5 days.

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.959-974
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• 2021

Forel-Ule Index (FUI) is an index which classifies the colors of inland and seawater exist in nature into 21 gradesranging from indigo blue to cola brown. FUI has been analyzed in connection with the eutrophication, water quality, and light characteristics of water systems in many studies, and the possibility as a new water quality index which simultaneously contains optical information of water quality parameters has been suggested. In thisstudy, Ocean Colour-Climate Change Initiative (OC-CCI) based 4 km FUI was spatially downscaled to the resolution of 500 m using the Geostationary Ocean Color Imager (GOCI) data and Random Forest (RF) machine learning. Then, the RF-derived FUI was examined in terms of its correlation with various water quality parameters measured in coastal areas and its spatial distribution and seasonal characteristics. The results showed that the RF-derived FUI resulted in higher accuracy (Coefficient of Determination (R²)=0.81, Root Mean Square Error (RMSE)=0.7784) than GOCI-derived FUI estimated by Pitarch's OC-CCI FUI algorithm (R²=0.72, RMSE=0.9708). RF-derived FUI showed a high correlation with five water quality parameters including Total Nitrogen, Total Phosphorus, Chlorophyll-a, Total Suspended Solids, Transparency with the correlation coefficients of 0.87, 0.88, 0.97, 0.65, and -0.98, respectively. The temporal pattern of the RF-derived FUI well reflected the physical relationship with various water quality parameters with a strong seasonality. The research findingssuggested the potential of the high resolution FUI in coastal water quality management in the Korean Peninsula.

• Korean Journal of Remote Sensing
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• v.38 no.5_2
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• pp.747-763
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• 2022

Ocean salinity affects ocean circulation on a global scale and low salinity water around coastal areas often has an impact on aquaculture and fisheries. Microwave satellite sensors (e.g., Soil Moisture Active Passive [SMAP]) have provided sea surface salinity (SSS) based on the dielectric characteristics of water associated with SSS and sea surface temperature (SST). In this study, a Light Gradient Boosting Machine (LGBM)-based model for generating high resolution SSS from Geostationary Ocean Color Imager (GOCI) data was proposed, having machine learning-based improved SMAP SSS by Jang et al. (2022) as reference data (SMAP SSS (Jang)). Three schemes with different input variables were tested, and scheme 3 with all variables including Multi-scale Ultra-high Resolution SST yielded the best performance (coefficient of determination = 0.60, root mean square error = 0.91 psu). The proposed LGBM-based GOCI SSS had a similar spatiotemporal pattern with SMAP SSS (Jang), with much higher spatial resolution even in coastal areas, where SMAP SSS (Jang) was not available. In addition, when tested for the great flood occurred in Southern China in August 2020, GOCI SSS well simulated the spatial and temporal change of Changjiang Diluted Water. This research provided a potential that optical satellite data can be used to generate high resolution SSS associated with the improved microwave-based SSS especially in coastal areas.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.390-401
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• 2023

Major components of lac coloring include laccaic acids A, B, C, and E. The Korean Food Additive Code regulates the use of lac coloring and prohibits its use in ten types of food products including natural food products. Since no commercial standards are available for laccaic acids A, B, C, and E, a standard for lac pigment itself was used to separate laccaic acids from the lac pigment molecule. A standard for each laccaic acid was then obtained by fractionation. To obtain pure lac pigment for use in food by High performance Liquid Chromatography Photo Diode Array (PDA), a C8 column yielded the best resolution among various tested columns and mobile phases. A qualitative analytical method using High Performance Liquid Chromatography (HPLC) Tandem Mass(LC-MS/MS) was developed. The conditions for fast and precise sample preparation begin with extraction using methanol and 0.3% ammonium phosphate, followed by concentration. The degree of precision observed for the analyses of ham, tomato juice and Red pepper paste was 0.3-13.1% (Relative Standard Deviation (RSD%)), degree of accuracy was 90.3-122.2% with r²=0.999 or above, and recovery rate was 91.6-114.9%. The limit of detection was 0.01-0.15 ㎍/mL, and the limits of quantitation ranged from 0.02 to 0.47 ㎍/mL. Lac pigment was not detected in 117 food products in the 10 food categories for which the use of lac pigment is banned. Multiple laccaic acids were detected in 105 food products in 6 food categories that are allowed to use lac color. Lac pigment concentrations range from 0.08 to 16.67 ㎍/mL.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.153-161
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• 2016

This study aims to determine the optimal maturity of strawberry fruits as affected by the application of lysophosphatidylethanolamine (LPE) and its optimal concentration for postharvest stability and quality. Prior to application of treatments, fruits that were classified into levels of maturity (0%, 50%, 70% and 100%) were air-dried for 40 minutes and stored in the refrigerator at $4^{\circ}C$ for 12 days. Fruits at 70% maturity were dipped into 0, 10, 50 and $100mg{\cdot}L^{-1}$ LPE solutions for 1 minute. A lower range of concentration (0, 2.5, 5, 10 and $25mg{\cdot}L^{-1}$) was applied to fruits at different maturity levels. Data on fresh weight, hardness at vertical and horizontal loading positions, color index and sugar content during storage were collected. Based on fruits with 70% maturity dipped in LPE concentrations, there were no significant differences found on fresh weight, color index and sugar content. However, the application of $10mg{\cdot}L^{-1}$ LPE gave the highest hardness at vertical loading position while $100mg{\cdot}L^{-1}$ had the lowest average. At lower range of LPE concentrations, fresh weight was not significantly affected by LPE application and maturity levels. Hardness of fruits was mainly based on the maturity of the fruits. Increased hardness was observed in the fruits with 70% maturity dipped into the $5mg{\cdot}L^{-1}$ of LPE solution. The hardness and Hunter's $L^*$ and $b^*$ value of 100% matured fruits gave lowest values despite the application of $25mg{\cdot}L^{-1}$ LPE 12 days after storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.259-266
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• 2011

This study was performed to develop an odor-reduced Korean traditional Cheonggukjang (fermented soybean paste) by adding Job's tears to Cheonggukjang made with soybean (control) only. The study included the determination of best addition percentage of Job's tears versus soybean, sensory evaluation, and aroma patterns and its components as well as proximate composition analyses of Cheonggukjang. Job's tears Cheonggukjang (CAJT) was prepared by inoculating Bacillus subtilis and fermented at $40^{\circ}C$ for 48 hours. Ratios of soybean : Job's tears for Job's tears Cheonggukjang were 1:1, 2:1, 3:1, and 4:1, respectively. In comparison of proximal composition, Job's tears Cheonggukjang was high in moisture and carbohydrates, but low in calorie, fat, protein, ash and amino nitrogen. The pH of CAJT was lower than those of control and conventional Cheonggukjang (CC) sold in the market, and the acidity was the lowest in CC. The color of Job's tears Cheonggukjang appeared the whiter and more yellowish, but less reddish in proportion to contents of Job's tears. The contents of viscous substances were higher in CAJT compared with those of control and CC. The contents of glutamic acid, the major components of viscous substances were lower in CAJT than in control and CC, and the contents of fructose higher in CAJT. The scores of sensory evaluation were the highest in Job's tears Cheonggukjang mixed with soybean : Job's tears=4:1. The aroma pattern of CC analyzed was conspicuously dissimilar to the control and CAJT and also discriminated by electronic nose examination. The pyrazines, volatile compounds peculiar to Cheonggukjang, were found to be lower in CAJT by SPME-GC/MS assay. Additionally, the acetic acid, butanoic acid, and naphthalene causing off-flavor were identified in CC, but not in Job's tears Cheonggukjang. The strength of odor through sensory evaluation was by far the lowest in CAJT among the groups. From the findings, it had shown that Job's tears Cheonggukjang would be produced successfully when the ratio of 4:1 (soybean : Job's tears) is employed. Also, it was proved that appropriate ratio of Job's tears addition makes Cheonggukjang odor-reduced and well accepted by people.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1385-1389
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• 2004

For the development of better Gulbi processing, brine salting method was applied for the Yellow croaker (Larimichthys polyactis). The changes of moisture contents, salt contents, and total microbial numbers in Yellow croaker were measured following different brine concentration (20, 30%), temperature (5, 25, 35$^{\circ}C$), and soaking time (1, 6, 12, 24 hours) by brine salting method. Rate of salt penetration into Yellow croaker muscle increased as higher brine concentration and higher dipping temperature. When compared to commercial products of Gulbi by dry-salting method, the moisture and salt contents in Yellow croaker showed similar values after treated with 20% brine at $25^{\circ}C$ for 1 hour. The weight of Yellow croaker increased about 4% when immersed it in 20% brine at 5$^{\circ}C$ for 24 hours. There was no weight change at $25^{\circ}C$ dipping temperature and reduced 7% of weight at 35$^{\circ}C$ dipping temperature. At 30% brine concentration, the weight of Yellow croaker reduced 1%, 9%, and 13% on weight at 5$^{\circ}C$, $25^{\circ}C$, and 35$^{\circ}C$, respectively. Total microbial counts in Yellow croaker muscle soaked at 30% brine showed 1 log lower numbers than 20%. The muscles had about 1 log higher microbial numbers than the treated brine solution. An ethanol extract of onion peel added to brine for giving better color and for preventing oxidation on Gulbi lipid. The treated group showed higher Land b values on Gulbi surface as well as antioxidant effect on the extracted oil.