• Food Science and Preservation
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• v.8 no.4
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• pp.374-378
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• 2001

We investigated the change of microfloral states during drying processing and storage of dried persimmon. Initial stave of drying, a total bacteria counts of dried persimmon which was made the rural region of Sangju province were higher than that of downtown but after 7 weeks, there was no differents. A total cell count of bacteria decreased during drying processing but mold and yeast increased. In a storage test of dried persimmon at a different temprature, 3$0^{\circ}C$, room temp. 4$^{\circ}C$, respectively, low temprature storage was effectvie not only to retard the growth of microorganism but also maintain the suitable appearence.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.205.2-205
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• 2003

가정에서는 쌀을 소비할 때 외기 조건 특히, 하절기와 같이 외기 온도가 높을 경우 함수율 감소, 지방산가 증가 및 해충발생 등 품질 손상이 급격히 발생한다. 따라서, 가정에서 쌀을 소비할 때 쌀의 품온을 가능한 낮춰 안전하게 저장하는 방법이 필요하다. 본 연구는 가정용 냉각쌀통을 이용하여 저온에서 쌀을 저장하면서 저장기간 중 품질변화를 측정하여 저온저장특성을 구명하는데 목적이 있다. 가정용 냉각쌀통은 매직 쌀장고(MRH-2501, Tongyang)를 이용하였으며, 대조구로 상온($25^{\circ}C$)에서 쌀을 14주간 저장하면서 1주일 간격으로 시료를 채취하여 함수율, 지방산가, 색도 및 표면변화를 측정하였다. 저장기간이 경과함에 따라 쌀의 함수율은 냉각쌀통의 경우 1.5%(w.b.), 상온저장의 경우 2.1%(w.b.)가 감소하였다. 지방산가는 냉각쌀통에서 저장 14주 후15.1(mg KOH/100g)로 나타났고, 상온저장에서는 8주 후 24.2, 14주 후에는 40.9(mg KOH/100g)로 급격히 증가하였다. 쌀의 색도는 저장기간이 경과함에 따라 증가하는 경향으로 나타났으며, 상온저장이 냉각쌀통에 비해 현저히 높게 증가하였으며, 저장 8주 후부터는 유의적인 차이를 나타내었다. 쌀의 표면에 세포벽은 냉각쌀통에 비해 상온저장에서 저장기간이 경과함에 따라 뚜렷하게 나타났다.

• Food Science and Preservation
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• v.18 no.5
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• pp.651-660
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• 2011

This study was conducted to evaluate the quality characteristics of and chilling injury development in 'Ooishiwase' plum fruits after harvest, according to the ripening stage and storage temperature. The fruits were harvested at three ripening stages (60, 80, and >90% skin color) and were then stored at 1, 4, 5, 6, and $20^{\circ}C$ cold-storage rooms for up to 48 days. The fruit quality parameters, respiration patterns, and chilling injury development were monitored during the storage periods and the three days of subsequent ripening at $20^{\circ}C$. The fruits harvested at the 60%-skin-color stage maintained the flesh firmness, color, weight loss, and TA, and their respiration rates and ethylene production were decreased compared with the 80%-or >90%-skin-color fruits, at a lower storage temperature. The major symptoms of chilling injuries in the Ooishiwase plums were gel breakdown, flesh browning, and flesh translucency. These symptoms appeared at all the low-storage-temperature and ripening treatment stages. When the fruits, however, were harvested at a more immature stage and were stored at a lower storage temperature, the chilling injury development decreased. These results show that the development of chilling injury in Ooishiwase plums is related to the climacteric behavior during cold storage.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.182-187
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• 2002

국내 저온저장고의 주류를 이루고 있는 컨테이너 박스형 저온저장고의 문제점은 재래식 제어방식으로 인한 성능저하 외에도 자체 구조적인 설계상의 문제점을 가지고 있다 이러한 구조적인 문제점을 열거하면 다음과 같다. 첫째, 한 축 방향에 설치되어있는 유니트 쿨러에서 토출되는 냉기에 의해 저장고 내의 공기를 냉각하는 형태이기 때문에 냉기의 분포가 고르지 못하여 균일한 온도 분포를 이루기 어렵다는 단점을 가지고있다. 둘째, 한 축 방향에서 토출되는 냉기가 맞은 편 벽면까지 도달해야 하기 때문에 풍속이 강해야 하며 이로 인해 저장 청과물이 냉해를 쉽게 입고 심한 증산작용에 의해 쉽게 표면건조나 중량감소를 가져온다. 셋째, 천장부와 측벽부가 90$^{\circ}$의 경사각을 가지고 있어 공기의 유동이 원활하지 못하여 에디현상으로 인한 온도나 풍속의 불균일 구간을 피해서 청과물을 저장해야 하기 때문에 그만큼 버려지는 공간이 많아 비경제적이다. 넷째, 위와 같은 문제점들 때문에 중ㆍ대형의 저온저장고를 컨테이너 박스형으로 설비 할 경우 보다 심한 온도 불균일과 냉기유동 분포를 보여 경제적인 손실이 더 커지게 되는 악순환을 낳게된다. 이에 따라 본 연구에서는 국내 저온저장고의 구조적인 설계상의 문제점을 인식하고 이를 해결하고자 3차원 CFD 시뮬레이션을 이용하여 저온저장고의 새로운 모델을 설계하였다. 이론 바탕으로 직접 저온저장고의 시작기를 개발하여 저장고 내부의 역 유동과 난류유통을 해석하였다. (중략)

• Horticultural Science & Technology
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• v.19 no.2
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• pp.135-139
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• 2001

The study was conducted to investigate quality changes by different shelf temperature after storage at $5^{\circ}C$ for 15 days. Fruits on the shelf at room temperature produced more $C_2H_4$ and $CO_2$ than those at $5^{\circ}C$ by 30% and seven times, respectively. By 10 days on the shelf, flesh firmness was held better at $5^{\circ}C$, while it was softened very rapidly at $13^{\circ}C$ and room temperature. In contrast, at low shelf temperature, contents of soluble solid did not show significant difference except that, in room temperature, it showed tendency to decrease. Sucrose content tended to be higher on the third day of marketing. At room temperature, however, all the sugar contents decreased from 10 days of marketing. Small quantity of ethanol and acetaldehyde were detected on the first day of marketing at $5^{\circ}C$ and $13^{\circ}C$, but they were high at room temperature. Also, these contents increased significantly with prolonging the shelf period and with rising marketing temperature.

• Food Science and Preservation
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• v.20 no.6
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• pp.766-774
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• 2013

The effect of storage temperatures ($0^{\circ}C$and $20^{\circ}C$) and packing functional film for fruit quality were examined in 'Fuyu' persimmon. The fresh weight loss was delay more effectively by the inhibition of transpiration when functional film was used. The firmness was effectively maintained in functional film packages at low temperature ($0^{\circ}C$), which might result from the beneficial combination of $CO_2$ and $O_2$. The soluble solid contents was higher with packing of functional film at $0^{\circ}C$ than at room temperature ($20^{\circ}C$). Highest $CO_2$ production in functional film bags was observed in room temperature storage after one week and thereafter declined sharply whereas lowest in 8 weeks. $CO_2$ concentration regardless of packing slowly increased to $5.2{\mu}L{\sim}10.2mL{\cdot}kg^{-1}{\cdot}h^{-1}$ until 8 weeks of low temperature due to persimmon respiration. Hunter 'b' value changed greatly yellowness according to temperature of storage but there were no significant differences among packaging treatments. Effects of functional film and low temperature in slower softening were consistent. This results suggested that the packing functional film at low temperature resulted in the best retention of quality market.

• Food Science and Preservation
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• v.19 no.2
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• pp.178-184
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• 2012

The physiochemical property, nutrient composition, and functionality of apple juice sterilized at a low temperature (LT, $70^{\circ}C$, 30 min) or a high temperature (HT, $100^{\circ}C$, 20 min) were analyzed. The pH of the apple juice that was sterilized at LT (pH 4.72) was higher than that of the apple juice that was sterilized at HT (pH 4.57), and the acidity of the apple juice that was sterilized at HT (8.90%) was higher than that of the other sample. The sugar content of the two apple juice samples was 15 $^{\circ}Brix$, and the apple juice samples had high potassium, malic acid, and glutamic acid contents. The total polyphenol contents of the apple juice samples that were sterilized at LT and HT were 27.39 mg/100 mL and 23.24 mg/100 mL, respectively. The apple juice that was sterilized at LT had a significantly stronger DPPH radical scavenging activity than the apple juice that was sterilized at HT ($p$ <0.01), and the apple juice that was sterilized at LT had a lower hydroxyl radical scavenging activity level than the other apple juice. Finally, the apple juice that was sterilized at LT showed significantly stronger activities that inhibit enzyme-related oxidation than the apple juice that was sterilized at HT ($p$ <0.05).

• 농업기술회보
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• v.50 no.2
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• pp.36-37
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• 2013

우리나라에서 감자는 거의 연중 생산되며, 최근 저온저장고 등의 산지유통시설이 보급되면서 홍수출하에 따른 가격폭락 현상이 줄어들고 있다. 특히 겨울철 시설감자는 재배하기 쉽고 단경기에 출하되기 때문에 소득 작목으로 크게 부각되고 있으며, 그 면적은 약 1.500ha에 이른다. 그러나 이상기상에 따른 저온피해, 동해, 일조부족 등은 시설감자 생산에 종종 피해를 주고 있으므로, 온도와 토양수분, 광도를 최적 상태로 유지하는 것은 시설감자 생산의 기본적인 요소이다.

• Food Science and Preservation
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• v.23 no.4
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• pp.471-478
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• 2016

For the distribution of fresh produce, the thermoelectric cooling system combined with thermo electric materials (TEM) and phase change material (PCM) was studied. The PCM used this study was produced by in-situ polymerization technology which referred microencapsulation of hydrocarbon (n-tetradecane and n-hexadecane). In this study, quality characteristics of bell peppers in thermoelectric cooling system combined with TEM and PCM were analyzed and control was placed in an EPS (expanded polystyrene) box. As a result of quality characteristics analysis, weight of bell peppers decreased and moisture content of bell peppers was 90.96~94.43% during storage. Vitamin C content of bell pepper decreased during storage and reduction ratio of control was higher than that of BPT-5 treatment(bell pepper in thermoelectric cooling system with PCM which is kept the temperature at $5^{\circ}C$). The result of color value, on 21 day, ${\Delta}E$ value of BPT-5 treatment was 5.05 while that of control was 41.8. On 21 day, total bacteria count of BPT-5 treated bell pepper shown less than that of control. In conclusion, it suggested that the thermoelectric cooling system combined with PCM improved quality of fresh produce during transportation and storage.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.04a
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• pp.125-126
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• 2002