• Journal of the korean academy of Pediatric Dentistry
• /
• v.26 no.2
• /
• pp.427-436
• /
• 1999

Preservation of the remaining periodontal ligament cells on an avulsed tooth is very important to the successful outcome of replantation. HBSS is recommended as the most suitable storage medium for the avulsed tooth that cannot be replanted immediately. But their availability near the site of an accident is doubtful. The purpose of this in vitro study was to compare periodontal ligament cells stored in different storage media obtained easily on the spot. Human periodontal ligament cells were collected from the premolar teeth extracted for orthodontic treatment. Cells were cultured in ${\alpha}-MEM$ culture medium containing 20% FBS, at $37^{\circ}C$ 100% humidity, in a 5% $CO_2$ incubator. Cells were cultured in 96 well culture plate, $5{\times}10^4$ cells per well with ${\alpha}-MEM$ and incubated for 24 hours. After discarding the medium, those cells were cultured in ${\alpha}-MEM$ contained with 10% FBS, pasteurized milk, sterilized saline, unstimulated saliva and bench-dried state at $25^{\circ}C$ room temperature for 30, 60, 90, 120, 180 minutes respectively. And then each group was measured using MTT assay. The results were as follows. 1. Between the group of each time, there was statistically significant difference. Periodontal ligament cells viability was highest in pasteurized milk and was reduced stepwisely in sterilized saline, unstimulated saliva and bench-dried state(p<0.05). 2. between the time of each group, there was statistically significant difference(p<0.05) but was no statistically significant difference at 90-120 minutes in pasteurized milk and at 60-90 minutes and 120-180 minutes in sterilized saline(p>0.05). In conclusion, HBSS as storage medium of an avulsed tooth is not practical on the spot. Insteadily pasteurized milk can be recommended to maintain the periodontal ligament cells viability.

• Food Science and Preservation
• /
• v.11 no.4
• /
• pp.485-490
• /
• 2004

Crude corn oil (CCO) was obtained through the expression-extraction process from corn germ. The CCOs of final process at $90^{\circ}C,\;70^{\circ}C\;and\;50^{\circ}C$ were stored in outdoor storage tanks. From the samples, refined CCO (RCCO) were prepared with $0\%,\;10\%\;and\;20\%$ excessive of phosphoric acid, caustic solution and acidic clay were used in degumming-alkali refining-bleaching process. RCCOs were stored at room temperature in dark places. The color change was not effected by the amount of phosphoric acid, caustic solution and acidic clay, but temperature of process affects the color change. Finally, the prevention for color reversion of RCCO could be obtained by lowering the temperature of final process and optimal temperature of RCCO in summer was found about less than $50^{\circ}C$.

• Food Science and Preservation
• /
• v.9 no.2
• /
• pp.131-136
• /
• 2002

Quality changes of satsuma mandarin (Citrus unshiu Marc. var. miyagawa) during storage by storage warehouse were investigated. Citrus were treated with 2000-folds diluted iminoctadime-triacetate solution and 1.5% chitosan with 0.5% CaCl$_2$ solution, and were at 30$\^{C}$ for 24 hr before storage. The citrus of about 12kg/26L plastic container were stored at room temperature, and at 4$\^{C}$ with 87% relative humidity. Decay ratio of citrus with precise temperature and humidity control were lower than the others during storage. Penicillium italicum Monilia candida Alternara citri, Mucor hiemalis, Phomopsis citri Botrytis cinerea, Phoma citricarpa Clomererella cingulata, Penicillium digitatum were identified as putrefactive microorganisms in citrus storage. Weight loss, moisture content of peel and flesh were decreased slowly during storage. 24% of original acid content were decreased at room temperature on 120 days storage, compared to 15∼18% loss on cold storage. Total sugar of citrus was decreased rapidly after 90 days, and vitamin C content were also decreased rapidly after 60 days during storage.

• Food Science and Preservation
• /
• v.10 no.2
• /
• pp.147-153
• /
• 2003

Quality changes of citrus tangor(Citrus kiyomi) during storage by chitosan and calcium treatment and storage warehouse were investigated. Citrus fruits were treated with 2000-folds diluted iminoctadime-triacetate solution, and 1.5% chitosan with 0.5% CaC1$_2$solution, and were at 30$^{\circ}C$ for 24 hr before storage. The citrus fruits of about 12 kg/26 L plastic container were stored at 4$^{\circ}C$ with 87% relative humidity. Decay ratio of citrus with precise temperature and humidity control were lower than the others during storage. Weight loss, moisture content of peel and flesh were decreased slowly during storage. 15 ∼ 18% of acid content were decreased on 120 days' storage. Vitamin C content were decreased rapidly during storage. 23 free amino acids were detected. Isoleucine and leucine were not detected, but alanine was detected only on stored citrus. Citrus fruits was kept well on its commodity quality for 3 month at 4$^{\circ}C$ with 87% relative humidity.

• Polymer(Korea)
• /
• v.31 no.6
• /
• pp.532-537
• /
• 2007

The rheological properties of the solutions of atactic poly(vinyl alcohol)(PVA) in dimethyl sulfoxide (DMSO) were investigated in terms of molecular weight distribution (MWD) of the polymer. The dynamic viscosity (${\eta}#$) and loss modulus (G") for the PVA/DMSO solutions with broader MWD were lower than those with narrower MWD at the similar $M_w$. It could be explained by the fact that the free volume for the solution with broader MWD at the similar $M_w$ was increased. The storage modulus(G#) of 14 wt% PVA/DMSO solutions with broader MWD was higher than that with narrower MWD at a lower frequency than 1.3 rad/sec, but lower than that with narrower MWD at a higher frequency (>1.3 rad/sec). The slopes of modified Cole-Cole plots of the 14 wt% solutions showed that as the MWD was broadened, the phase transition with frequency was more noticeable.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.6
• /
• pp.956-963
• /
• 1995

Twenty esters, 14 alcohols, 5 aldehydes, 5 ketones, 5 lactones, 2 S-containing compounds and 1 hydrocarbon are identified by GC-MS from volatile compounds in a glucose solution containing Yeat-Carbon-Base medium fermented for 64 hrs by Saccharomyces bayanus at pH 3.5, $25^{\circ}C$, 400rpm and 35L/h of aeration for 24hrs. Under the different conditions of conservation(1~4), ethyl 2-hydroxy-4-metjhylpentanoate, ethyl succinate, nonanol and phenylacetaldehyde are produced during conservation of fermented solution. 17 esters increased during conservation at $13^{\circ}C$ for 12 weeks and the increase of ethyl 9-hexadecenoate is important among 13 esters increased during conservation at $35^{\circ}C$ for 24hrs. During conservation, aldehydes increased at $35^{\circ}C$, but decreased at $13^{\circ}C$ and the great increase of isobutanal, benzaldehyde and phenylacetaldehyde is observed at $35^{\circ}C$. Alcoho and lactones increased but ketones decreased during conservation.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.31 no.6
• /
• pp.823-828
• /
• 1998

The objective of this study is to investigate cryoprotective effects of corn starch enzyme hydrolysates of nonsweet and low-calories on denaturation of frozen fish protein. The cryoprotective effects of were examined in Alaska pollack actomyosin solution by changes in SDS-PAGE pattern, solubility, and $Ca^{2+}$-ATPase activity. When samples stored for 0 and 30 days were compared on SDS-PAGE patterns, severe changes in all bands were shown on the control sample regardless of storage temperature, especially in myosin heavy chain (MHC). Not much difference no appeared the electrophoretic pattern in case of the samples containing sucrose at any storage temperature during 30 days of storage. The cryoprotective effect of the hydrolysates were markedly dependant on storage temperature and no MHC band was found in the samples stored at $-5^{\circ}C$. The SDS-PAGE patterns of sample stored at $-20^{\circ}C$, however, completely maintained after 30 days or storage. When the samples were stored at $-5^{\circ}C$, the solubility of the sample containing sucrose was retained at $90\%$ after 30 days of storage, whereas dramatically decreased in other samples. The samples including sucrose, D.E. 10, 15, and 20 revealed $90\%$ in solubility when stored at $-20^{\circ}C$. The tendency of remaining $Ca^{2+}$-ATPase activity was almost shown the same as that of solubility.

• Food Science of Animal Resources
• /
• v.28 no.5
• /
• pp.549-554
• /
• 2008

Liposomes were prepared from egg yolk phospholipids to study their physical properties and stability at various storage conditions. Under storage conditions at different pH levels, the particle sizes of liposomes increased at the range of pH 1-2, and the absolute values of $\xi$-potentials were reduced at the range of pH 1-4. The leakage of sulforhodamine B (SRB), a fluorescent dye which is encapsulated in the liposome, increased greatly at pH 2-4. At different storage temperatures, the particle size of liposomes increased from the 10 days of storage at $4^{\circ}C$ and the 40 days at 20 and $35^{\circ}C$. The $\xi$-potentials decreased slightly later during storage under 4, 20 and $35^{\circ}C$. At the storage temperature of $50^{\circ}C$, the leakage of SRB was the greatest. Therefore, we concluded that the pH conditions lower than pH 6 and high temperature of $50^{\circ}C$ are not conducive to storing liposomes. The results obtained here may prove helpful in developing liposome-based encapsulation and diagnostic reagents.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.10
• /
• pp.1312-1317
• /
• 2008

Physicochemical changes were investigated for the shelf-life extension of cultured wild-ginseng roots during storage with various pre-treatments with blanching, CAMICA-SD and DF-100 and treatments with citric acid and vitamin C. The pH of cultured wild-ginseng roots showed the range of $6.06{\sim}6.42$ at $10^{\circ}C$, but showed higher ranges of $6.08{\sim}6.91$ and $6.08{\sim}8.68$ at 20 and $30^{\circ}C$, respectively. Browning index (a/b) was increased with increasing storage temperature, and the index at 10 and $30^{\circ}C$ were 0.405 and 0.469 after 2 weeks, respectively. Browning index and viable cell number of CAMICA-SD pre-treatment showed little changes compared to pre-teatment with blanching or DF-100. When the cultured wild-ginseng roots were treated with 1.0% citric acid and 0.2% DF-100 after pre-treatments with CAMICA-SD, viable cell number was slightly increased to $4.9{\times}10^2CFU/g$ for 3 weeks storage at $10^{\circ}C$. The mixture of citric acid and DF-100 was also used to prevent the growth of microbiology and to reduce browning reaction, especially enzymatic browning reaction. The mixture might effectively extend shelf life of the cultured wild-ginseng roots.

• Korean journal of food and cookery science
• /
• v.13 no.3
• /
• pp.293-298
• /
• 1997

The changes of microorganisms, pH, color and flavor were examined in the chicken treated with O％, 1%, 2%, and 3% lactic acid solutions during the storage at 4$^{\circ}C$. Lactic acid treatment inhibited the growth of mesophiles, psychrotrophs, and enteric bacilli as the concentration increased, however, it was not effective on yeasts and molds. Extension of lag phase for mesophilic bacteria and suppression of log phase for psychrotrophs and enteric bacilli were observed in the growth inhibition patterns. The pH of the chicken increased during the storage and antimicrobial effect of lactic acid appears to be due to mainly the decrease of pH. No flavor change of the chicken was observed by any lactic acid treatment, however, 3％ lactic acid caused discoloration of the chicken.