This study is in order to the effect of 1-methlycyclopropene (1-MCP) treatment and film package as modified atmosphere packaging (MAP) on the changes in fruit quality factors of 'Daehong' peaches during cold storage. The concentrations of 1-MCP were treated at 1μL·L-1 and 2μL·L-1, and peaches in film package were stored for 28 days in cold storage at 5±1°C and 85±5% RH. The fruits stored carton box were used as a control of MAP, and 1-MCP free fruits were used as the control of both packages. Rate of fresh weight loss during storage was not significantly different between groups with and without 1-MCP treatment, but was higher in the box package than in the MAP. The control group had a higher incidence of both gases with the 1-MCP treatment group showing statistically significantly low. Carbon dioxide in the package was lowered by about 12% compared to the non-treated group, and the ethylene concentration was maintained at 1μL·L-1, showing a significance low compared to other treated groups. As the storage period elapsed, the firmness of 1-MCP and MAP treated fruits remained significant at 5-9% compared to the control group. Regardless of the packaging method Hunter a* values of exocarp and mesocarp were significantly higher in fruit treated with 1-MCP 1μL·L-1 treatment than in the control group, and anthocyanin was significantly higher in the fruit during the storage period, especially high in MAP. In summary, fruits of MAP group with 1-MCP 1μL·L-1 had rate of lower respiration and ethylene production, and little changes in firmness, Hunter a* values of exo-carp and meso-carp, and anthocyanin, which is considered the most suitable method for preserving postharvest quality of the peach cultivar during the storage.
The purpose of this study was to investigate the effects of sterilization, storage period and washing yuzu, according to the washing method, during the storage period. The results showed that the fungus size increased as the storage period increased, and no mold occurred in the yuzu washed with ozone water until 20 days. After 30 days of storage, a mold of 124.1±13.9 mm2 was observed. The no-treatment sample had a fungus of 814.5±72.8 mm2 in size on day 0 and the fungus the largest fungus was 6,362±636.7 mm2 on day 30. In the case of water treatment, the fungus was 286.4±31.5~4,836.4±484.6 mm2 in size. The results of the study confirmed that washing yuzu with ozone water has a sterilizing effect.
To enhance the efficacy of Abeliophyllum distichum leaves, extracts were prepared using different solvents for hydrolytic enzyme-treated Abeliophyllum distichum leaves. Physicochemical quality and antioxidant activity were measured. Soluble solids, reducing sugar, ascorbic acid, flavonoids, and polyphenols contents showed the lowest values in the control without enzyme treatment. However, they showed high contents in ethanol extract. In the case of enzyme treatment, their values were higher than those of the control. In particular, verbascoside content increased about 220 times more than that of the control group when treated with enzymes and extracted with 50% ethanol. pH was lowered upon enzymatic treatment. Regarding DPPH radical scavenging activity, for enzyme-free, 25% ethanol extract showed the highest activity among extracts with different solvents. For cellulase and pectinase-treated leaves, water extract showed the highest DPPH radical scavenging activity among extracts with different solvents. For leaves treated with enzyme combination, 50% ethanol extract showed the highest DPPH radical scavenging activity among extracts with different solvents. Regarding ABTS radical scavenging activity, it was generally higher in the 50% ethanol extract than in the water extract and 25% ethanol extract. In particular, verbascoside content was increased when the extract was prepared by co-treatment with enzymes and 50% ethanol.
Endocrine-disrupting chemicals found in many commercial products may interfere with the normal functioning of the endocrine system and are unsafe because of their cumulative effect on the human body. However, little is known about the effects of combinations of endocrine-disrupting chemicals in humans. Methoxychlor and bisphenol A are toxic to male reproductive organs. Therefore, we studied the effects of methoxychlor and bisphenol A on male reproductive function. Male mice were divided into four treatment groups: control, 400 mg methoxychlor, 1 mg bisphenol A, and 400 mg methoxychlor + 1 mg bisphenol A/kg/day. Methoxychlor and bisphenol A were dissolved in sesame oil and acetone and administered orally for 4 weeks. After administration, the weight and histological changes in the testicles and epididymis, sperm count and health were observed biochemical tests and whole blood counts were performed. The results showed that the mice in the bisphenol A and methoxychlor + bisphenol A groups gained more weight than those in the control and methoxychlor group. The weights of the testes and epididymis were higher in the experimental groups than in the control. Sperm motility and progression were significantly reduced in the bisphenol A and methoxychlor + bisphenol A groups. Histological observation showed a reduced number of sperm, smaller seminiferous tubules, and destroyed lumen in the methoxychlor + bisphenol A group compared to the other groups. In conclusion, our study showed that methoxychlor and bisphenol A destroy male reproductive tissues and decrease sperm quality.
To improve the shelf-life of Centella asiatica, Centella asiatica was treated with gel packs containing slow-released chlorine dioxide (ClO2) gas at 3-5 ppm for 20 days at 4℃. The weight loss rate, as well as the changes in pH, color, and texture of the treated samples, were investigated. The weight of the control and ClO2 gas-treated samples was decreased during the storage period. The change in weight of the control was slightly faster than that of the samples treated with 3 and 4 ppm ClO2 gas. The pH of the control and the ClO2 gas treated samples were decreased during the storage period and there was no significant difference between the control and ClO2 gas treated samples. Concerning color (lightness, redness, and yellowness) changes of Centella asiatica during the storage period, there was no significant difference between the control and ClO2 gas treated samples. The change in shear force in the leaf and stem of Centella asiatica during the storage period was slightly lower in the 4 ppm ClO2 gas treated samples (in the leaf) compared to the control and 3 and 4 ppm ClO2 gas treated samples (in the stem) compared to the control and 5 ppm ClO2 gas treated sample.
Understanding the characteristics of reservoir water quality is fundamental in reservoir ecosystem management. The water quality of reservoirs is affected by various factors including hydro-morphology of reservoirs, land use/cover, and human activities in their catchments. In this study, we classified 83 major reservoirs in South Korea based on nine physicochemical factors (pH, dissolved oxygen, chemical oxygen demand, total suspended solid, total nitrogen, total phosphorus, total organic carbon, electric conductivity, and chlorophyll-a) measured for five years (2015~2019). Study reservoirs were classified into five main clusters through hierarchical cluster analysis. Each cluster reflected differences in the water quality of reservoirs as well as hydromorphological variables such as elevation, catchment area, full water level, and full storage. In particular, water quality condition was low at a low elevation with large reservoirs representing cluster I. In the comparison of eutrophication status in major reservoirs in South Korea using the Korean trophic state index, in some reservoirs including cluster IV composed of lagoons, the eutrophication was improved compared to 2004~2008. However, eutrophication status has been more impaired in most agricultural reservoirs in clusters I, III, and V than past. Therefore, more attention is needed to improve the water quality of these reservoirs.
The purpose of this study was to examine the microbiological and physicochemical changes on packaged tofu stored at temperatures of 5, 13, 23, and 30oC, and measure the consumable period from the expiry date to ultimately evaluate the microbiological safety on the extension of the consumable period. From the investigation, the pH value of tofu at each storage temperature (5, 13, and 23oC) showed a slight decrease over the storage period, although there was no significant change. The hardness of packaged tofu decreased more rapidly as temperature and storage time increased and the tofu started to show signs of decomposition at the same time. Analysis on the microbial change of tofu at different storage temperature revealed that the number of general bacteria also increased as the temperature increased. It was further found that packaged tofu takes 25 days at 5oC, 7 days at 13oC, and 1 day at 23oC from the expiry date until the general bacteria count is at least at the early decomposition level which is 10oC log CFU/g. However, no coliform bacteria was detected from tofu after storing at 5, 13 and 23oC. When packaged tofu was stored at 5oC, the L value changed significantly after 26 days, whereas the a and b values showed no significant change during the storage period (P>0.05). When storing tofu at 13oC and 23oC the L value decreased after 8 and 3 days, respectively. However, both a and b values increased (P<0.05).
빈번한 가뭄의 피해는 수자원의 양극화를 초래하고 있다. 국내에서는 2011년부터 2017년 사이에 국지적이고 주 기적인 이상 가뭄이 지속되어 10년 가뭄 빈도로 설계된 소규모 저수지의 저수율이 감소하였다. 이러한 저수율의 감소 는 수질을 떨어트릴 수 있고 이미 확보된 용수의 사용마저 제한할 수 있다. 따라서 가뭄에 대비하고 극복하기 위해서 는 수질관리와 가뭄 빈도의 재산정이 필요하다. 이 연구는 저수지에서 수질 변화의 원인인 잠재적 오염물질을 추정하고, 가뭄 기간 동안 저수지의 저수율 감소와 그에 따른 수질 변화를 검토한 것이다.
This research aims to investigate pudding with grain-added yogurt for its quality characteristics and viability during cold storage. The yogurt was fermented until its pH was 5.10±0.05 after inoculating the probiotic strain (Bifidobacterium lactis, BB-12) into the milk base containing grains. The yogurt was added to prepare probiotic puddings. During cold storage of the puddings at 4±1oC for 4 week, the quality characteristics (pH, acidity, texture) and the viability of BB-12 in pudding were determined and compared to control (only milk base). As a result, MR had a significantly lower pH and higher acidity than those of other samples. In texture properties, including hardness, gumminess, and chewiness, MSIR showed the significantly highest value, and the pudding with inulin was significantly higher than rice flour in all textures. For the viability of BB-12, pudding with milk was significantly lower than pudding containing milk and soymilk, suggesting that soymilk helps maintain viability. MR showed significantly higher viability than MI in the milk-based pudding, indicating that rice flour is more effective than inulin. Therefore, the addition of soymilk, inulin, and rice can maintain quality characteristics and viability of BB-12 in the pudding.
Cymbidium is one of the most popular and economically important species cultivated as a commercial ornamental crop. The objectives of this study were to determine the appropriate electrical conductivity (EC) treatments of nutrient solution, which gives the highest spike production and quality. Three-year-old Cymbidium ‘Lovely Smile’ plants were grown in the environmentally controlled Information and Communication Technology (ICT) smart greenhouse at Seoul Women’s University. The EC of the nutrient solution was changed in three distinct stages: vegetative, flower initiation, and flower development. The EC treatments were 1-0-1 (dS·m-1, EC101), 1-1-1 (dS·m-1, EC111), 2-1-2 (dS·m-1, EC212), 2-2-2 (dS·m-1, EC222), 3-2-3 (dS·m-1, EC323), 3-3-3 (dS·m-1, EC333) and the pH was adjusted to 6.0–6.5. Pseudobulb diameter increased in the plants treated with EC 101 and EC111 compared to the plants treated with EC 2.0–3.0 dS·m-1 at the reproductive stage 28 weeks after nutrient solution treatment. Flower spike production per pot and pseudobulb showed the highest values in the plants treated with EC111 of 3.3 and 1.4, respectively. Flower spikes length was the highest in the plants treated with EC 1.0 dS·m-1 and stem thickness, number of flowers, and fresh weight were the largest in the plants with EC 1.0 dS·m-1 among the EC treatments. Flower spikes had the worst quality (e.g., plant growth and flowering quality) in the plants treated with EC 3.0 dS·m-1 among the EC treatments. Floral bud and flower development took place 1–2 weeks earlier in the plants treated with EC 101, 111, and 212 than the other treatments. Flower diameter showed the highest values in the plants treated with EC 1.0 dS·m-1 among the EC treatments and flower color showed higher L* and b* values and lower a* values in the plants treated with EC 3.0 dS·m-1 compared to EC 1.0 and 2.0 dS・m-1. Nutrient solution of EC 1.0 dS·m-1 (EC111) can be recommended to improve flower spike quality and advanced flower development of Cymbidium.
최고품질 벼 품종의 외래품종 대체를 위하여 국내 재배 외래품종의 선호 요인 분석을 위한 기초자료를 제공하고자 ‘추청’ ‘고시히카리’ 등 국내 선호도가 높은 외래품종의 취반시 미립의 모양과 체적변화를 조사한 바, 1. 취반 시간에 따른 입장은 최고품질 벼의 경우 ‘삼광’이 199%로 가장 높았고 ‘일품’이 172%로 가장 낮았으며 삼광’의 경우 배양 후 5~10분 사이에 입장이 가장 빠르게 늘어났고 ‘일품’은 취반시간에 따라 일정한 비율로 증가하였다. 2. 국내에서 선호되는 외래 품종의 경우 취반시 미립의 신장변이의 폭이 적었으며 ‘삼광’이나 ‘하이아미’에 비하여 일정한 비율로 증가하였으며 ‘고시히카리’와 ‘히토메보레’는 취반 15분 이후부터 신장율의 변화가 상대적으로 적었다 3. 미립 신장지수는 ‘삼광’과 ‘하이아미’가 ‘일품’보다 높았으며 ‘삼광’은 취반 10분 후 신장지수의 변화가 거의 일어나지 않았고 일품’과 ‘고시히카리’는 취반후 미립의 모양이 상대적으로 작게 변하였다. 5. 최고품질 벼 및 외래품종의 취반한 후 미립 모양은 조사한 모든 품종의 미립 표면이 다소 불규칙적으로 팽화하였지만 ‘고시히카리’의 경우 백미 원형을 가장 잘 유지하고 있는 것으로 나타났다.
In this study, we investigated the effects of the ripening level (50% and 100%), storage temperature (1°C and 10°C), and storage period (0, 7, and 14 days) on the fruit quality of the strawberry (Fragaria × ananassa Duch) cultivars “Arihyang” and “Kuemsil”, which are commonly grown for export in South Korea. Strawberry plants of each cultivar were grown in a plastic greenhouse, and fruit samples were harvested in January 2019 to evaluate the fruit hardness, gray mold rot, anthocyanin content, sugar content, and antioxidant activity. We found that “Arihyang” had a greater fruit hardness than “Kuemsil” across all storage periods excluding the day of harvest, and that fruit stored at 1°C had a greater hardness than fruit stored at room temperature (10 ± 2°C) for both cultivars. In incidence of gray mold rat, “Kuemsil” had a higher than “Arihyang”. The soluble solid content was highest at 7 days after harvest for both cultivars, with the exception of “Kuemsil” following storage at 1°C. The anthocyanin content was higher in “Arihyang” than in “Kuemsil” and was also greater in fruit that had been stored at room temperature due to the faster ripening time. Finally, the DPPH activity of fully ripened fruit tended to decrease as the storage period increased, while the ABTS activity was the same across all treatments. These findings demonstrate that “Arihyang” are more advantageous for long-term distribution as well as export than “Kuemsil”, and recommend that the two new cultivars of strawberry be cool stored at 100% ripening state and eaten within 7 days.
This study was conducted to investigate the temperatures inside and outside the pot as well as the quality characteristics of traditional Doenjang made by seven different farmers, in the Gyeonggi province during fermentation. The outside temperature of each region in the province was 5 to 10℃ higher in one place, in which fermentation took place inside the glass greenhouse, compared to other regions, while six other places showed similar changes in temperature. The moisture contents of the samples decreased according to the progress of the fermentation period from 53.6~62.3% to 51.0~58.5%. The salinity generally increased from 9.7~14.2% to 10.6~16.3% except for samples B and D, which declined from 17.0~17.2% to 16.6~16.9%. The amino-type nitrogen contents increased from 180.3~557.8 mg% to 437.3~840.7 mg%. The ammonia-type nitrogen contents decreased from 116.3~561.9 mg% to 70.7~149.2 mg%. Overall, the color of Doenjang was similar, but sample E had higher a and b values than the other regions, and the total bacterial count in the entire region was similar.
연구목적은 성인 지적장애인들의 수영 프로그램 참여에 따른 자아효능감과 운동 몰입, 건강관련 삶의 질의 변화를 분석하는 데 있다. 연구대상은 지적장애인 거주시설에서 거주하고 있는 성인 지적장애인 12명이며, 수영 프로그램에 12주간 참여하였다. 이에 따라 대상자들의 자아효능감과 운동 몰입, 건강 관련 삶의 질의 변화를 분석하였다. 자아효능감 평가는 전반적 자아효능감 척도를 활용하였으며, 일반적, 사회적 신체적 자아효능감을 평가하였다. 운동 몰입 평가는 스포츠 몰입척도를 활용하였으며, 인지몰입과 행위몰입의 수준을 평가하였다. 건강관련 삶의 질 평가는 건강관련 삶의 질 척도를 활용하여 전반적 건강 관련 삶의 질의 수준을 평가하였다. 그 결과, 대상자들은 수영 프로그램 참여에 따라 자아효능감과 운동 몰입, 건강관련 삶의 질의 수준이 통계적으로 유의미하게 향상되었다. 수영 프로그램의 참여는 성인 지적장 애인들의 자아효능감과 운동 몰입, 건강관련 삶의 질의 수준을 향상시키는 데 긍정적으로 작용한다. 이에 따라서, 성인 지적장애인들을 대상으로 수영 프로그램의 적용을 고려해볼 필요가 있을 것이다.
This study was carried out to determine the optimum temperature of the jicama pickle solution by evaluating physicochemical and sensory characteristics at various temperatures. The soaking solution of the jicama pickle was prepared at different temperatures (95, 75, 50, and 25oC). During storage, the titratable acidity, Brix, and the salinity of the jicama pickles increased, and these values increased with increasing temperature of the soaking solution. The higher the temperature of the soaking solution, the lower the L and b values. In all samples, the hardness increased rapidly until the 5th day of storage, and then gradually decreased. During storage, the jicama pickles showed a high tendency to harden at soaking solution temperatures of 75 and 95oC. Sensory evaluation indicated that the taste, flavor, crispness, and overall preference of the jicama pickle were higher at a soaking solution temperature of 75oC and above. The higher the temperature of the soaking solution, the higher the acceptability. Based on these results, we conclude that soaking solution temperature of 75°¦95oC in the manufacture of jicama pickles had a positive effect on the reduction in tissue softening and the sensory properties of the jicama pickle.
This study was carried out to investigate the changes of the microbiological contamination levels, pH, acidity, solid contents, total phenol contents, and color difference of cold-brew coffee products during 4 weeks at room and cold temperatures. The 17 sample coffees were purchased from regional cafes in Jeonju. Each coffee was self-blended by the cafes. Esherichia coli was not detected in all the samples, but bacteria were detected in 1 sample and yeast and molds were detected in 4 samples. Of the samples stored at room temperature (25oC) after 4 weeks, general bacteria were detected in 4 samples (3.0×101 cfu/ml-1.7×103 cfu/ml), and yeast and molds were detected in 11 samples (1.3×101 cfu/ml - 3.1×105 cfu/ml). In the case of the samples stored at cold temperature (4oC), general bacteria were detected in 3 samples, and yeast and molds were detected in 6 samples although the level of contamination was lower than that at room temperature. pH and acidity decreased during the storage period, but the total phenol content did not change. In the case of chromaticity, redness and yellowness tended to decrease.