The present study aimed to analyze the developmental trajectories of English achievement and exposure time through private education, utilizing univariate and multivariate latent growth curve analysis. This study used a subset of the Gyeonggi Education Panel Study data from 2012 to 2017. The results indicated consistent disparities in the growth of English achievement, depending on the student’s proficiency levels at the starting point. In particular, the early exposure to private tutoring was significantly and closely related to the initial status and the growth trajectory of English achievement. When the sample was classified by urbanicity, the findings suggested that the gap in English achievement was likely to increase over time across the two regions, with a stronger correlation with private tutoring found in urban areas. These results underscore the need for educational intervention for students in less advantageous conditions, and they provide valuable pedagogical implications for teaching English in the Korean EFL context.

본 연구에서는 다양한 식물성 지방 대체제가 돼지고기 패티의 이화학적 특성 및 관능 특성에 미치는 영향을 평가 하고자 하였다. 동물성 지방 처리군, 식물성 기름 처리군, 비드 처리군 첨가에 따른 영향을 분석하였으며, 실험을 통해 지방 함량은 낮추면서 물리적 및 관능적 측면에서 돼지 등지방을 사용한 패티와 큰 차이를 나타내지 않음을 확인 하고자 하였다. 본 연구에서는 기존의 지방대체 방법인 식물성 기름 첨가와 식물성 기름 유화물 첨가 뿐 아니라 식물성 고체 지방 대체제를 제조할 수 있는 방법을 제시하였으며, 이를 육가공 제품에 적용하여 다양한 지방 대체제의 효과와 비교했다는 점에서 기존 지방대체 연구와 차이점이 있을 것으로 판단된다. 또한, 연구 결과 식물성 고체 지방 대체제는 패티의 조리손실을 줄이고 보수력을 개선하는 등 품질을 향상시킬 수 있었으며, 패티의 부드러움과 다즙성에 영향을 주어 선호도가 높은 것으로 분석되었다. 이는 새로운 지방 대체제의 적용 가능성에 대한 기초 연구 자료로 제공될 수 있다.

Radiological impact analyses were carried out for a near-surface radioactive waste repository at Gyeongju in South Korea. The RESRAD-ONSITE code was applied for the estimation of maximum exposure doses by considering various exposure pathways based on a land area of 2,500 m2 with a 0.15 m thick contamination zone. Typical influencing input parameters such as shield depth, shield materials’ density, and shield erosion rate were examined for a sensitivity analysis. Then both residential farmer and industrial worker scenarios were used for the estimation of maximum exposure doses depending on exposure duration. The radiation dose evaluation results showed that 60Co, 137Cs, and 63Ni were major contributors to the total exposure dose compared with other radionuclides. Furthermore, the total exposure dose from ingestion (plant, meat, and milk) of the contaminated plants was more significant than those assessed for inhalation, with maximum values of 5.5×10−4 mSv‧yr−1 for the plant ingestion. Thus the results of this study can be applied for determining near-surface radioactive waste repository conditions and providing quantitative analysis methods using RESRAD-ONSITE code for the safety assessment of disposing radioactive materials including decommissioning wastes to protect human health and the environment.

In this study, spray-dried double emulsion loaded bromelain was applied to Japanese Spanish mackerel fillets to develop fish-type, elderly-friendly foods. Japanese Spanish mackerel, treated with spray-dried double emulsions, were stored at 4oC for 24 h. For the characterization of emulsion particles, the particle size, ζ-potential, and morphology were determined. The color, TBARS, VBN, TMA, hardness, and adhesiveness of fish fillets treated by emulsion were measured for physicochemical properties. All the particle sizes of spray-dried emulsion were decreased while their double emulsion structure was maintained. Spray-dried emulsion reduced the color difference of fish fillets and did not catalyze lipid oxidation and protein decomposition. Values of TBA, VBN, and TMA of all fish did not exceed 0.5 mg MDA/kg, 30 mg/100 g, and 10 mg/100 g, respectively, which are considered edible limits regardless of bromelain or emulsion application. Bromelain modified fish fillets' hardness and adhesiveness to be suitable for elderly food, although it was encapsulated in the emulsion. Thus, spray-dried fish oil W/O/W double emulsion-loaded bromelain can be applied as a fish tenderizer, and this study’s results can be utilized to develop elderly-friendly food.

Excessive salt intake in body induces health risks resulting in high blood pressure or heart diseases. Therefore, the low salt concentration and salt-tasted food is needed by means of the modification of the manufacturing process. The purpose of this study is to study the effect of inhomogeneous salt localization in bread to enhance the saltiness of encapsulated salt. 0, 0.5, 1.0, 1.5, and 2.0% of liposome encapsulated salt (LS) was added into the baking of white pan bread. The final salt concentration was adjusted to 2.0% by addition of salt. After baking the bread, moisture content, loaf volume, fermentation rate, color, texture analysis, salt release rate, and sensory test were measured. From this study, moisture content had no significant difference in control and treatments (p>0.05), except for 2.0% LS. The lightness in all treatments was higher than the control’s (p<0.05), whereas there was no significant difference in hardness (p>0.05). From the sensory test, the bread added 2.0% LS showed the highest value from the salty taste. Moreover, it is related to the highest release rate of salt represented at 2.0% LS. In conclusion, the salty intensity of bread can be enhanced by the salt localization using the encapsulation of salt.

Cryoprotectant is a substance used to protect biological tissue from freezing injury. However, there was few research paper on application of cryoprotectant in food stuff although its benefits was approved from the biological cell tissues. The objective of this study was to investigate the effect of the sugar addition as a cryoprotectant on the properties of frozen soybean sprouts. Before freezing process, the samples were blanched at 100°C for 1 min to observe the influence of blanching treatment. The blanched or non-blanched soybean sprouts was immersed in sugar solution as cryoprotectant, and continuously, the samples were frozen at -18°C for 24 h. Their physicochemical properties such as drip loss, hardness, color and cellular tissue were analyzed after thawing in running water. In our study, the drip loss of blanched sample without sugar was 43%, and comparatively, blanched one with sugar was 20% which was the lowest value among all samples. There was no significant difference of hardness between sample with sugar and without sugar. From our results, it was supposed that sugar can protect the soybean sprouts during freezing process regardless blanching process.

Soybean peptide (SP) exhibited low intestinal absorption at oral administration due to its fragile structure under gastric digestion. Therefore, we have attempted to encapsulate peptide by cross-linkage interaction between positive charged chitosan (CS) or chitosan oligosaccharide (CSO) and negative charged peptide. The CS (or CSO) with SP nanoparticles were prepared by using ultrasonification technique. The objective of this study was to find the optimal processing method by changing concentration, pH, and homogenizing conditions. We measured physicochemical properties such as particle size, zeta-potential, encapsulation efficiency (EE%), release rate (RR) and antioxidant ability of samples. The results showed that the optimal processing method was using 0.5% (w/v) CSO (diluted by pH 3 Acetic acid buffer) mixed with 0.5% (w/v) SP (diluted by pH 6 buffer) by 9:1 ratio. Afterwards, using high-speed mixer at 12,000 rpm for 3 min, and then passed 2 times through an ultrasonicator (50% power, 3 min). In this way for processing, the particle sizes of CSO/SP nanoparticles were approximately 300 nm, zeta-potential were approximately 45 mV. In addition, the EE% and RR of CS/SP nanoparticles was higher than the CSO/SP nanoparticles. The increase in antioxidant ability of SP was attributed to the affected by CS/CSO microcapsules. In conclusion, this research can befoundation for the manufacturing process of CS/SP nanoparticles, and it was expected that the future application of this nanoparticle in food matrix.

Recently, semi-dried sweet potato is popular as a natural snake for children’s dessert. The drying condition was optimized to obtain high quality of sweet potato by oven drying process. The mashed yellow and chestnut sweet potato was dried using the oven drier at different temperature (50, 60, 70, and 80°C) then evaluated for the moisture content, appearance observation, texture properties, and sugar contents and sensory test in every 2, 6 and 12 hours. During the dehydration and drying process, the ending point of moisture content divided in three zone from 0-2 hour, 4-6 hour and 8-12 hour. The moisture content was dramatically decreased from 0 hour - 8 hour, but after 8 hour there is no significant decrease. Yellow sweet potato dried at 80°C for 6 hours was investigated as good product base on the sensory test, hardness value, and color appearances as compared to chestnut potato.