• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.937-941
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• 2009

현재 가장 일반적으로 사용되는 미생물 배양 용기인 petri dish를 통해 제조된 미생물 배양 배지의 보관은 냉장과 실온 보관 시 수분 증발에 대한 보호 효과가 극히 낮아 한 달 이상으로 배지 품질을 유지하기 어려운 단점이 있다. 따라서 본 연구는 petri dish를 이용하여 미생물 배양 배지를 제조할 때 glycerol 등 7종의 보습성분을 첨가하여 이에 따른 미생물 배양 배지의 수분 증발 억제 효과와 표준균주별 증식반응을 비교, 분석한 것으로 결과적으로 sodium lactate를 제외한 6종의 보습성분이 배지의 수분 증발을 억제하는 효과가 있으며 이들에 대한 표준균주별 증식반응에서도 양성의 결과를 보여주었다. 앞으로 본 연구의 결과는 즉시 사용 배지(PPM, Pre-Plated Media)의 유통기한 연장 효과 및 품질향상에 유용한 자료로 활용될 수 있을 것으로 기대된다.

• Journal of Sericultural and Entomological Science
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• v.53 no.1
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• pp.50-54
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• 2015

Mulberry fruit is common to keep a frozen storage because of the very high water content. Because freezing-storing cost is generated before the processing or sales, farmers of mulberry fruit production are weighted in financial burden. In addition, mulberry fruit has difficulty in expanding consumption by made in the simple processed products like the mulberry jam, mulberry juice, mulberry enzyme, alcohol, etc. Recent, frozen fruits including frozen blueberries, frozen strawberries, frozen mango, frozen rich, frozen mulberry fruit has been started to sell in the large discount stores and convenience stores. However, there is restricted sales in only special place that have the frozen distribution facilities. So, for the income improvement and consumption promotion of mulberry farmers facing these difficult situations, we developed the processing method of semi-dried mulberry fruit using the vacuum freezing dryer. The frozen mulberry fruit which was stored below $-40^{\circ}C$ is to dry in a vacuum freeze dryer, at $30{\sim}35^{\circ}C$, 23 ~ 24 hours. Semi-dried mulberry fruit seperated respectively. It had soft texture, and maintained shape, size and flavor. In particular, semi-dried mulberry fruit can be stored at room temperature.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.446-451
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• 2015

The market for green vegetable juice (GVJ) is growing owing to the increasing demand for healthy food; however data on the safety and quality of GVJ are poorly reported. The objective of this study was to investigate the change in microbial community in GVJ during storage and its contamination by E. coli O157:H7. The microbial community was analyzed via culturable and non-culturable methods at 5, 10, and $25^{\circ}C$ for different storage times. In the non-culturable method, denaturing gradient gel electrophoresis (DGGE) was used. The initial bacterial concentration was $2.92{\times}10^5CFU/mL$, which exceeded the limit prescribed by the Korean Food Hygiene law. The results of the DGGE analysis indicated that the microbial community during storage was diverse and the spoilage lactic acid bacteria were prevalent at a later stage. Other bacteria such as Rahnella, Citrobacter, Pseudomonas, and Cyanobacteria were identified. Thus, the results strongly emphasize the need to pay attention to GVJ production safety, especially with respect to temperature control, in order to prevent the growth of foodborne pathogens such as E. coli O157:H7 and other spoilage bacteria.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.2
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• pp.379-388
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• 1998

본 연구는 악안면보철용 실리콘의 색안정성을 연구하기 위하여 실리콘 재료로 MDX 4-4210 Silicone(Dow Coming. Midland, Mich.)과 A-2186(Factor II, Lakeside, Az)을 사용하고 Mars Violet. Golden Yellow, Red yellow, Raw Sienna등 4종의 색소(Factor II, Lakeside, Az)를 이용하여 시편을 제작한 후 1군은 섭씨5-55도에서 700회 thermocycling하였고, 2군은 10%의 비눗물(Ivory, Proctor & Gamble Inc,. Toronto, Ontario)에 담아 섭씨15-55도에서 700회 thermocycling하였다. 3군은 10%의 비눗물에 담아 75일간 실온에서 보관하였으며 4군은 실온의 암실에 75일간 보관하였다. 5군은 초여름인 6월 중순부터 75일간 햇볕이 잘드는 곳에 위치하였다. 이를 측색색차계(Model TC-6FX, Tokyo Denshoku Co., Japan)를 이용하여 측정하고 색변화를 연구한 결과 다음과 같은 결론을 얻었다. 1. $L^*$값의 경우 모든 실험군에서 대조군에 비해 유의하게 감소하였다. 2. $a^*$값의 경우 대부분의 실험군에서 증가하였으나 Raw sienna, Mars violet색소를 사용한 실험 3.4.5군의 MDX4-4210의 경우 감소하는 경향을 보였다. 3. $b^*$값은 실험1.2.3군의 경우 대부분 감소하였고 실험4.5.군의 경우에서 증가하였으나 3.4.5군의 경우에서 대부분 유의한 차이가 없었다. 4. ${\Delta}E$의 값은 실험군에서 대부분 감소하였으나 4군의 A-2186에서 증가하는 경향을 보였고 실험2군의 Red yellow, Mars violet을 사용한 MDX4-4210에서 비교적 큰 변화를 보였다. 5. $L^{\ast}$값과 a값의 변화량의 합은 A-2186의 경우에서 크게 나타났으나 ${\Delta}E$값의 변화량은 MDX4-4210에서 크게 나타났다. 6. $L^*$값의 변화량의 합은 실험4군에서 크게 나타났으며 $a^*$값은 1군에서, $b^*$값과 ${\Delta}E$값의 변화량의 합은 2군에서 크게 나타났다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1325-1332
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• 2015

Lettuce (Lactuca sativa) is an important dietary leafy vegetable that is primarily consumed as a fresh or salad material. It has a number of cultural varieties with green and/or red color. Carotenoids and anthocyanins are known to be responsible for these two colors, respectively. In this study, carotenoid and anthocyanin contents were determined to evaluate the stability of these functional pigments during storage at home. Analyses were carried out at the beginning, 3, 6, 9, and 12 days after harvest. In the course of storage at room temperature, total carotenoid levels rapidly decreased, and the decrease was found to be greatest during the first 3 days. Meanwhile, carotenoid level slightly changed within the first 9 days at $4^{\circ}C$ after harvest. This result suggests that carotenoids in green lettuce are more stable when refrigerated than at room temperature. Meanwhile, total anthocyanin content in red lettuce did not significantly decrease during storage at room temperature and $4^{\circ}C$, which indicates that anthocyanins have higher stability during storage compared with carotenoids in green lettuce. Anthocyanin extract exhibited higher antioxidant activity than carotenoid extract based on 2,2'-azino-bis(3-ethylbenzothazoline-6-sulfonic acid) (ABTS) radical scavenging assay. Antioxidant activity of anthocyanin extract may also be estimated directly by the presence of another potent hydrophilic antioxidant compound, which is ascorbic acid in this extract. In addition, anthocyanin extract showed about a 5-fold higher amount of anthocyanins than carotenoids in the carotenoid extract. The high correlation between carotenoid content with ABTS radical scavenging activity indicates that ABTS assay is more suitable than 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay for detecting antioxidant capacity of carotenoid extract from lettuce.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.149-155
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• 2002

Two pesticides commonly used for lettuce cultivation including chlorpyrifos and procymidone were subjected to a field residue trial to ensure safety of terminal residues in the harvest. After pesticides were applied at standard and double rates in a foliar spray, leaf persistence of their residues was investigated far 10 days prior to harvest. Even though far exceeded the tolerances, initial leaf residues were rapidly dissipated with time and remained only 0.4$\sim$7.2% of the residues in the harvest. As well fitted by the first-order kinetics, biological half-lives of the pesticide residues in lettuce leaves ranged 1.2$\sim$2.6 days. Slow dissipation of the residues in the harvest was observed during storage at room temperature and 4$^{\circ}C$ for 7 days. Portions of dislodgeable residues which resided in detergent washings decreased as time elapsed. Patterns in dissipation and distribution of dislodgeable residues were not largely affected by the application rate of pesticides. It is concluded that timing of pesticide application, that is, pre-harvest interval would be the first factor to determine the terminal residue level in edible portions of lettuce.

• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.465-468
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• 2008

현재 가장 범용적으로 사용되는 미생물 배양 용기인 Petri Dish는 배지 제조 후 냉장과 실온 보관 시수분 증발에 대한 보호 효과가 적어 세 달 이상 보관하기 어려운 단점이 있어 즉시 사용 배지(pre-plated media) 개발에 장애가 되고 있다. 본 연구는 미생물 배지의 장기 저장이 가능하도록 고안된 LOP plate의 수분 보호능에 관한 것으로, LB 배지를 표준 배지로 해서 4, 25, 32 및 $37^{\circ}C$ 네 개의 온도영역과 진공 포장 및 비 포장 조건에서 Petri Dish와 비교한 결과, 각 온도 조건별로 LOP의 탁월한 수분 보호능을 확인 할 수 있었다. 따라서 향후 LOP를 이용한 장기 저장과 즉시 사용이 가능한 pre-plated media와 관련된 제품 개발이 가능할 것으로 기대된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.1
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• pp.66-72
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• 2017

Potato greening determines the shelf life and affects the marketability of this tuber. Various stresses during handling and storage interact to affect the tuber's physiological status and can affect the rate of greening. This study investigated the effects of storage temperature on tuber greening and shelf life in unwashed and washed potatoes of the cultivar Superior. Physiological and biochemical changes were examined during 15 days at room temperature ($23{\pm}2^{\circ}C$) under cool-white fluorescent light after storage for 1 month at different temperatures ($4^{\circ}C$, $20^{\circ}C$). Hunter a values were negative (-) for washed potatoes after 3 days (-0.8) and 15 days (-2.5) at room temperature following 1 month of storage at $4^{\circ}C$ while positive (+) values were observed for unwashed potatoes after 15 days at room temperature. The Hunter ${\Delta}E$ values of washed potatoes previously stored at $4^{\circ}C$ for 1 month increased after 3 days at room temperature compared with those of unwashed potatoes. The total chlorophyll content of washed potatoes was higher than that of unwashed potatoes. The highest correlation was observed between the Hunter ${\Delta}E$ value and Hunter a value (-0.93506), while a positive correlation coefficient (0.89806) was observed between greening criteria and Hunter ${\Delta}E$ value by using colorimetry. We conclude, therefore, that there is a biosynthetic link between temperature-induced chlorophyll accumulation and tuber greening in storage.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.127-132
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• 2012

This study was conducted to investigate of changes for organic acids in takju during storage conditions. Two types of takju, unsterilized and sterilized, were used. Acetic acid, citric acid, lactic acid, malic acid and succinic acid were detected in sample. Residues of malic acid was not detected after 7 days storage in room temperature($25^{\circ}C$). In contrast to lactic acid was increased by times after storage. Acetic acid concentrations was gradually increased in room temperature but was not changed in cold temperature($4^{\circ}C$). After storage for 10 days, the organic acid residues lactic acid > citric acid > succinic acid > malic acid > acetic acid in unsterilized takju. Compared to unsterilized sample, organic acid residues in sterilized sample was not significantly changed. Consequently, organic acids residues mainly affected by sterilization.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.112-119
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• 2006

We investigated the changes in the volatile flavor components of domesticated Codonopsis lanceolata, which were packed in woven polypropylene (WP) film or low density polyethylene (LDPE) film and stored for 15 and 30 days at refrigerated ($2{\sim}4^{\circ}C$) or room ($18{\sim}20^{\circ}C$) temperature (hereafter referred to as WP-RE-15, WP-RO-15, LDPE-RE-15, LDPE-RO-15, WP-RE-30, WP-RO-30, LDPE-RE-30 and LDPE-RO-30). 167 volatile flavor components were identified in the fresh domesticated Codonopsis lanceolata by GC/MS. The volatile flavor components which were identified in the domesticated Codonopsis lanceolata stored for 15 days were as follows ; LDPE-RE (117 components), WP-RO (65 components), WP-RE (49 components), and LDPE-RO (48 components). After 30 days, the numbers of components were as follows : LDPE-RE (99 components), WP-RO (94 components), WP-RE (46 components), and LDPE-RO (85 components). In all conditions, the following 7 volatile flavor components were identified; 1-hexadecene, 2,6-dimethyl-2-octanol, 2-methyl-2-dodecanol, ${\alpha}$-cedrene, ${\beta}-selinene$, farnesane, and isoledene. According to the sensory evaluation, the freshness of domesticated Codonopsis lanceolata was best maintained with LDPE film and under chilled conditions.