• KSBB Journal
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• 제14권1호
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• pp.91-95
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• 1999

P. phosphoreum의 고정화에 있어 중요한 것은 Matrix의 선택이며, Matrix로서 sodium algnate만을 사용하여 고정화하는 것보다는 strontnum chloride를 첨가하였을 때 세포의 bio-iummescence 유지도가 증가하였다. 저장 온도에 따른 bio-iummescence 유지도와 관련하여 -$70^{\circ}C,\;-20^{\circ}C,\;20^{\circ}C$에서 저장한 세포의 경우 저장 1일 후에 급격한 bioluminescence의 감소를 보였으나 $4^{\circ}C$ 에서 저장한 세포는 bioluminescence의 유지도가 15일 이상 이어졌다. 따라서 P. phosphoreum의 bioluminescence 안정성에 있어 가장 좋은 결과를 나타낸 것은 2.5%(W/W)sodium alginate와 0.3M(W/V)strontnum chloride 를 사용하여 고정화한 세포였으며 저장 온도는 $4^{\circ}C$였다.

• 한국식품위생안전성학회지
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• 제4권1호
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• pp.29-36
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• 1989

In order to investigate the Storage time of chicken eggs, several physico-chemical tests from chicken eggs store at 5, 13 and 27$^{\circ}C$ were examined. Egg samples were collected from six poultry farms. Egg stored at 5$^{\circ}C$ based on the depth of air cell and specific gravity, were all acceptable until 17 days ; on the egg yolk coefficient and pH of the egg white and egg yolk until about 10 days. Egg stored at 13$^{\circ}C$, based on the depth of air cell. were acceptable by about 10 days of storage, but on the other physico-chemical tests by about 7 days. Egg samples stored at room temperature(about 27$^{\circ}C$) base on the depth of air cell, were acceptable by about 5 days of storage ; on the specific gravity by 4 days ; and on the egg yolk coefficient and pH of the egg yolk and egg white by 3 days. The results of this study showed that egg stored at 5$^{\circ}C$ were considered acceptable by 10 days of storage ; at 13$^{\circ}C$ by 7 days ; at room temperature (27$^{\circ}C$) by 3 days.

• 한국식품위생안전성학회지
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• 제10권2호
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• pp.97-102
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• 1995

For improved preservation of boiled-dried anchovies, the current preservation method of corrugated-cardboard box packaging and freezing below -18$^{\circ}C$ was compared to the nylon/polyethylene(NY/PE) packaging along with cooling temperature ranging from 5$^{\circ}C$ to 1$0^{\circ}C$ as well as ambient condition for eight months by determining physicochemical quality of stored samples. Lipid oxidation of stored anchovies and their browning increased with storage time. The phenomenon was delayed under the conditions of lower temperature and air-tight packaging. As quality-indicative criteria of stored anchovies, carbonyl value(r=-0.989), browning (r=-0.949) and color a value(r=-0.989), browning(r=-0.965), Hunter's color b value(r=-0.949) and color a value(r=-0.940) showed a highly-negative correlations with organoleptic qualities of the samples. Based on the above results, air-tight packaging in a laminated film and subsequent storage at cooling temperature was found to be a possible alternative to the current freezing-storage of boiled-dried anchovies from the physicochemical point of view.

• 한국재료학회지
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• 제30권12호
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• pp.687-692
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• 2020

A zinc-air battery consists of a zinc anode, an air cathode, an electrolyte, and a separator. The active material of the positive electrode is oxygen contained in the ambient air. Therefore, zinc-air batteries have an open cell configuration. The external condition is one of the main factors for zinc-air batteries. One of the most important external conditions is temperature. To confirm the effect of temperature on the electrochemical properties of zinc-air batteries, we perform various analyses under different temperatures. Under 60 ℃ condition, the zinc-air cell shows an 84.98 % self-discharge rate. In addition, high corrosion rate and electrolyte evaporation rate are achieved at 60 ℃. Among the cells stored at various temperature conditions, the cell stored at 50 ℃ delivers the highest discharge capacity; it also shows the highest self-discharge rate (65.33 %). On the other hand, the cell stored at 30 ℃ shows only 2.28 % self-discharge rate.

• 원예과학기술지
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• 제30권5호
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• pp.519-526
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• 2012

혐기처리 녹차를 알루미늄 포장에 보관하여 상온, $4^{\circ}C$, $-10^{\circ}C$에 저장 시 품질관련 화학성분인 총질소, 총아미노산, 탄닌, 카페인, 엽록소, 비타민 C 및 지방산은 저장기간이 길어질수록 함량이 감소되었다. 각 성분의 함량 감소폭은 $-10^{\circ}C$ 저장이 상온, $4^{\circ}C$에 비해 적었으며, 함량 감소는 상온에 비해 8개월, $4^{\circ}C$에 비해서는 4개월 정도 지연되었다. 저장 시녹색을 나타내는 'a'값이 감소할수록 품질이 저하되는데, 혐기처리 녹차의 표면 녹색을 나타내는 'a'값은 12개월 저장 시 상온 > $4^{\circ}C$ > $-10^{\circ}C$ 순으로 저장온도가 높을수록 녹색이 감소됨을 알 수 있었다. 형상, 향, 맛 등으로 평가하는 관능평가는 100점 만점에 점수가 낮을수록 품질이 저하되며, 저장온도에 따라 혐기처리 녹차의 품질이 상이하였는데 $-10^{\circ}C$ 12개월 저장 시 80점, $4^{\circ}C$ 8개월 81.1점, 상온 4개월 80.4점으로 저장온도가 낮을수록 품질이 양호하였다. 따라서 본 연구의 내용을 종합한 결과, $-10^{\circ}C$를 혐기처리 녹차의 가장 효과적인 저장온도로 제시하고자 한다.

• Mycobiology
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• 제51권6호
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• pp.445-451
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• 2023

Shiitake mushroom (Lentinula edodes) hold high nutritional and medicinal value as they contain an abundance of health-promoting compounds. However, the effect of long-term postharvest storage on the variation in the levels of health-promoting compounds has not been extensively studied. In this study, we investigated the changes in the levels of phenolic compounds, antioxidants, eritadenine, and ergothioneine in shiitake mushrooms stored at three different temperatures (1, 3, and 5 ℃) for 4 weeks. Compared to mushrooms stored at lower temperatures, those stored at 5 ℃ exhibited a higher level of total phenolics in their pileus after 2 weeks of storage; however, storage at 5 ℃ also increased the deterioration of the fruiting body of these mushrooms. In mushrooms stored at all temperatures, the eritadenine content in the pilei tended to increase up to 2 weeks of storage. In contrast, the ergothioneine content in the pileus decreased during storage, with a significantly lower level detected in mushrooms stored at 5 ℃ for 4 weeks. Together, these results suggest that the mechanisms underlying the accumulation of phenolics and eritadenine may be related to mushroom deterioration during storage. Our findings indicate that the levels of health-promoting compounds in shiitake mushrooms are influenced by storage temperature, suggesting the potential to control adjustments of specific bioactive compounds by regulating storage conditions.

• 한국주거학회논문집
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• 제20권3호
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• pp.105-112
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• 2009

The purpose of this study is to investigate a top floor, indoor, thermal environment by comparison between the indoor air temperature and the rooftop surface temperature, and between the indoor air temperature and the outdoor air temperature using an experimental model. The model experiment was conducted with 4 cases,: no-rainfall, 1 em-height, 10 em-height and 20em-height of rainfall on the rooftop. According to the results of the height of stored rainfall, the average air temperature difference between the indoor and outdoor air with 1, 10 and 20 em-height of rainfall on the rooftop was $4.0^{\circ}C$, rooftop $1.2^{\circ}C$ and rooftop $1.0^{\circ}C$, respectively. The upper 10 em-height of rainfall on the rooftop acted to decrease the indoor air temperature on the top floor.

• 한국작물학회지
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• 제49권5호
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• pp.410-414
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• 2004

To understand the postharvest characteristics of soybean sprouts, 5-day-old sprouts were harvested, packed in PE film, and stored at 4, 12, and $20^{\circ}C$ for up to 4 days. In addition, the sprout respiration rate was measured after storage at 4, 8, 12, 16, 20, and $24^{\circ}C$ for up to 20h. During the first day of storage at $20^{\circ}C$, the sprouts maintained temperature-dependent longitudinal growth, especially of hypocotyl length; hypocotyl and root grew 0.8cm and 0.2cm, respectively. The hypocotyl thickness decreased by 11, 13, and $18\%$ after 4 days of storage at 4, 12, and $20^{\circ}C$, respectively. No temperature-dependent differences in fresh weight, dry weight, or water content were found, despite decreases of $3\%$ over the 4 days of storage. A significant postharvest decrease of $50\%$ in vitamin C content was observed in the sprouts stored at $20^{\circ}C$ for 3days. Based on the $CO_2$ production rate, the soybean sprouts exhibited an increase in respiration in proportion to the storage temperature; sprouts stored at 8, 12, 16, 20 and $24^{\circ}C$ showed approximately 2, 5, 6, 11, and 17 times, respectively, than the respiration rate of sprouts stored at $4^{\circ}C$. These results indicate the importance of low temperature storage during market circulation for minimizing the postharvest morphological and nutritional degradation of soybean sprouts.

• 한국축산식품학회지
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• 제44권1호
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• pp.74-86
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• 2024

Eggs that have been hard-boiled are frequently used as ready-to-eat food. Refrigerated and frozen storage of hard-boiled eggs causes issues, such as customer rejection owing to textural changes. The objective of this research is to ascertain how storage temperature affects hard-boiled eggs' alteration in texture over time. Medium-sized brown shell eggs were acquired from a local market, boiled at 100℃ for 15 min, and then stored at room temperature (25℃), refrigeration (4℃), and freezing (-18℃) conditions for 0, 12, 24, and 48 h. Fourier transform infrared spectroscopy (FTIR), texture profile, visual observation using a gemological microscope, free amino acid content, and color were measured. Freezing had a substantial impact on the eggs' hardness, gumminess, chewiness, and cohesiveness (p<0.05). The FTIR spectrums confirmed the textural changes in bonds of amide A (3,271 cm^-1), amide I (1,626.2 cm^-1), amide II (1,539.0 cm^-1), C=O stretch of COO^- (1,397 cm^-1), asymmetric PO₂^- stretch (1,240 cm^-1). Microscopic images confirmed structural changes in eggs stored at -18℃. The free amino acid content was lower in fresh and frozen eggs than in the rest (p<0.05). However, there was no discernible variation in the egg white's color when eggs were kept at 4℃ (p>0.05). Salmonella spp. was found exclusively in eggs kept at room temperature. In conclusion, hard-boiled eggs did not exhibit structural or chemical changes when stored at 4℃ for up to 48 h compared to freezing and room temperature conditions.

• 한국식생활문화학회지
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• 제19권1호
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• pp.30-42
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• 2004

김치냉장고에서 배추김치에 가장 적합한 발효온도와 시간 및 저장온도를 결정하기 위하여 발효와 저장 온도-시간 조합을 달리하여 16주 동안 저장하면서 배추김치의 품질 특성 변화를 분석하였다. pH의 변화는 발효온도가 높을수록 pH가 크게 감소하여 $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합과 $5^{\circ}C$ 6일 발효/$-1^{\circ}C$ 저장 조합의 경우 초기 1주 동안 pH가 크게 감소한 이후에는 아주 서서히 감소하였다. Hardness와 chewiness는 발효온도가 높을수록 더 낮은 값을 보였는데 발효가 진행됨에 따라 서서히 감소하는 경향을 나타냈고 특히 초기 4주 동안 크게 감소하였다. 관능적 특성에서 탄산미는 $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합에서는 4주. $5^{\circ}C$ 3일 발효 또는 6일 발효/$-1^{\circ}C$ 저장 조합에서는 8주 후가 가장 좋았다. 신맛은 $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합에서는 8주. $5^{\circ}C$ 3일 또는 6일 발효/$-1^{\circ}C$ 저장 조합에서는 12주후에 강한 신맛을 주었고 무발효/$-1^{\circ}C$ 저장 조합에서는 16주 후까지 신맛이 서서히 증가되었다. 따라서 총 기호도는 $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합에서는 4주. $5^{\circ}C$ 3일 또는 6일 발효/$-1^{\circ}C$ 저장 조합에서는 8주 후가 가장 좋았다. 총 균수는 발효온도가 높을수록 높았고 $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합의 경우 5일 후에 $4.47{\times}10^8$으로 최고치를 나타낸 후에 16주 후에는 $1.51{\times}10^5$까지 감소하였다. 젖산균 수는 $5^{\circ}C$ 6일 발효/$-1^{\circ}C$ 저장 조합의 경우 Leuconostoc은 6일 후에 $1.05{\times}109$으로 Lactobacillus는 5일 후에 $1.35{\times}109$으로 최고치를 나타내 $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합의 경우보다 많은 것으로 나타났다. 이상의 결과로부터, $20^{\circ}C$ 24시간 발효/$-1^{\circ}C$ 저장 조합의 김치냉장고에서 배추김치는 4주가 최적 가식기간이었고, $5^{\circ}C$ 6일 발효/$-1^{\circ}C$ 저장 조합과 $5^{\circ}C$ 3일 발효/$-1^{\circ}C$ 저장 조합에서는 8주가 최적 가식기간인 것으로 분석되었다.