• Korean journal of food and cookery science
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• v.11 no.3
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• pp.261-266
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• 1995

The survival and growth of Staphylococcus aureus and Listeria monocytogenes in fish homogenates (flounder, shrimp and oyster homogenate) and tryptic soy broth (TSB) were tested during storage at simulated ambient (35$^{\circ}C$), refrigerated (5$^{\circ}C$) and frozen (-20$^{\circ}C$) temperature. A similar growth pattern of S. aureus at 35$^{\circ}C$ was observed in fish homogenates and TSB. Survival of S. aureus decreased at refrigerated or frozen temperature and that was greater at -20$^{\circ}C$ (0.3-1.2 log reduction/6 weeks) than at 5$^{\circ}C$ (1-1.6 log reduction/3 weeks). Viable cells of L. monocytogenes increased rapidly at 35$^{\circ}C$ in flounder homogenate, shrimp homogenate and TSB but after a prolonged lag period in oyster homogenate. During 3 weeks of storage at 5$^{\circ}C$, the levels of L. monocytogenes increased 3.8-5.0 log cycles in flounder homogenate, shrimp homogenate and TSB whereas levels increased 2.2 log cycles in oyster homogenate. Viable cells of L. monocytogenes during 6 weeks of frozen storage decreased 1.5-1.8 log cycles in flounder homogenate, shrimp homogenate and TSB while decreased 2.8 log cycles in oyster homogenate.

• The Korean Journal of Ecology
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• v.25 no.6
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• pp.389-393
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• 2002

Effects of environmental factors on in vitro pine pollen performance were investigated. Pinus densiflora and P. rigida pollen grains collected at Mt. Kwanak, Korea were used. Three environmental factors, such as pollen storage temperature, pollen culture temperature and nutrient condition in medium, were tested. To determine the storage temperature effects on pollen viability, pine pollen was stored at $-70^{\circ}C$, $-12^{\circ}C$, $4^{\circ}C$ and $22^{\circ}C$. Pollen viability was substantially extended at the storage temperatures of $-12^{\circ}C$ and $4^{\circ}C$ for more than 300 days. To elucidate the culture temperature effects on pine pollen germination and tube growth, pollen grains were cultured at the temperatures from $5^{\circ}C$ to $40^{\circ}C$ at $5^{\circ}C$intervals. The germination rate and tube growth were highest at $25^{\circ}C$ and decreased above $30^{\circ}C$. To investigate boron and sucrose effects on pollen tube growth, the pollen was cultured at different sucrose and boric acid concentrations. Germination rate was optimal in germination medium containing 3 or 5$\%$ sucrose with 0.01 $\%$ boric acid. These results indicate that the pine pollen can be stored for considerable length of time without noticeable loss of viability at storage temperature below or near $0^{\circ}C$. Optimal germination medium conditions were established for pine pollen. Therefore, pine pollen can be used for many biological and environmental monitoring researches.

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.387-394
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• 2015

The red snow crab lives at a depth 200-2,000 m in the east coast. It has a smooth taste with a rich texture. However mostly red snow crab are only utilized materials. For seafood development, research is needed on using red snow crab in various products. In this study, quality changes in fried rice prepared with red snow crab meat, red snow crab emulsion sauce and red snow crab effluent were investigated. Physicochemical, microbiological and sensory characteristics were determined during storage at -20, 4 and $25^{\circ}C$ for 5 weeks to assess changes in the quality of the fried rice. The pH and acidity values did not show any significant differences at $-20^{\circ}C$. The VBN and TBA values of fried rice stored at 4 and $25^{\circ}C$ were significantly higher than those of fried rice stored at $-20^{\circ}C$ during the same storage period. The viable cell count of the fried rice stored at $-20^{\circ}C$ changed little during the storage period. During storage at $25^{\circ}C$, the overall quality was initially 8.0, but rapidly decreased to 1.0 after 5 weeks. In conclusion, the best storage temperature for both quality and safety was $-20^{\circ}C$. The storage condition for instant rice containing red snow crab affects the quality and we confirmed the applicability of using materials from red snow crab.

• Food Science and Preservation
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• v.23 no.2
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• pp.155-161
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• 2016

This study aimed to investigate the effects of pretreatments blanching, roasting, drying, and storage temperatures ($25^{\circ}C$, $4^{\circ}C$ and $-10^{\circ}C$) on their quality of lotus leaves. As a result, the lotus leaves retained a good appearance when stored at $25^{\circ}C$ for 5 days, $4^{\circ}C$ for 30 days, and $-10^{\circ}C$ for 90 days, regardless of the pretreatment used. At the same storage temperatures, pH, soluble solids, total acid content, polyphenols, and microorganisms were significantly different among the pretreatments (p<0.05). Soluble solids, pH, and total acid contents were not significantly different for the same pretreatments at different storage temperatures. However, the polyphenol, oxalic acid, and tartaric acid contents of lotus leaves were significantly different after drying and blanching treatments. In particular, it was shown that polyphenol content of the lotus leaf was affected by both pretreatment and storage temperature. In conclusion, the lotus leaves appeared in good condition until 5 days at $25^{\circ}C$, 30 days at $4^{\circ}C$, and 90 days at $-10^{\circ}C$, regardless of the pretreatment while influenced by storage temperature.

• Food Science and Preservation
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• v.5 no.3
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• pp.224-230
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• 1998

In order to establish proper storage conditions for ginger, the quality changes of gingers stored at three different temperatures(7$^{\circ}C$, 12$^{\circ}C$ and 20$^{\circ}C$) and three different relative humidities(75%, 85% and 95%RH) were investigated during 150 days of storage. Gingers stored at 7$^{\circ}C$ and 20$^{\circ}C$ showed rapid quality deterioration due to chilling injury and spouting respectively in any range of relative humidity. Ginger stored at 7$^{\circ}C$ was staled to show symptoms of the chilling injury such as moldiness, shrivelling, discoloration etc after 30 days of storage ; then it was deteriorated after 90 days of storage. Ginger stored at 20$^{\circ}C$ was completely lost its storage-life after 30 days of storage because of high sprouting ratio. However ginger stored at 12$^{\circ}C$, 75%RH showed better quality than ones stored at both 7$^{\circ}C$ and 20$^{\circ}C$, but it was not so good as the one at 7$^{\circ}C$, 95%RH. Consequently storage conditions of 12$^{\circ}C$, 95%RH was observed the best effecive condition for keeping rhizomes in good quality from weight loss, spouting, mouldiness and so on.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1178-1182
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• 2005

Survival of thermotolerant Lactobacillus reuteri KUB-AC5 in $20\%$ (w/v) skim milk was found to be $11.3\%$ after spray drying by using a pilot scale spray dryer with inlet temperature at $170^{\circ}C$ and outlet temperature at $85^{\circ}C$. The ability of dried cell to produce antimicrobial activity was not affected by the spray drying. The model system for predicting viability of spray-dried L. reuteri KUB-AC5 during long-term storage was established, based on the Arrhenius equation, and verified by experimental data, because the viability of cells during storage can be correlated with storage temperature. The viability during storage at $30^{\circ}C$ declined more rapidly than that storage at $4^{\circ}C$.

• Food Science and Preservation
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• v.16 no.4
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• pp.499-505
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• 2009

Quality changes in fresh-cut potatoes during storage at $4^{\circ}C$ after treatment with low-temperature blanching and antibrowning agents were studied. Fresh-cut potatoes were treated by dipping for 1.5 min in a browning inhibitor solution containing 0.5% (w/v) ascorbic acid, 0.5% (w/v) citric acid, 0.5% (w/v) sodium chloride, 0.1% (w/v) trehalose, and 0.005% (w/v) biotin, at $60^{\circ}C$, with subsequent cooling for 1.5 min and storage at $4^{\circ}C$. The browning properties of fresh-cut potatoes were examined by measurement of polyphenol oxidase (PPO) activity and total phenolic content. Changes in quality attributes over a 14-day period were assessed in terms of titratable acidity, pH, water-soluble solid level, and gas analysis at $4^{\circ}C$. During storage, PPO activity increased, with the lowest activity seen after about 7 days of storage. Treatment with antibrowning solution at $4^{\circ}C$ increased visual sensory attributes during storage. Low-temperature blanching in distilled water more effectively inhibited browning compared with exposure to browning inhibitor solution, as assessed after 7 days of storage. Fresh-cut potatoes respired aerobically after different treatments during storage at $4^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.609-614
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• 1991

Thermal stability and quality change during storage of red pepper oleoresin were studied. Upon heat treatment, carotenoids in oleoresin from red pepper were more stable under nitrogen than air. In the thermal stabilities, the presence of air at $100^{\circ}C$ for 3 hours and 10 hours were 69.1% and 42.3%, respectively ; whereas, in the presence of nitrogen, 95.4% and 92.3%, respectively. In contrast, capsaicin was comparatively stable upon heat treatment in the presence of air. The retentions of capsaicin at $100^{\circ}C$ for 3 hours and 10 hours were 84.7% and 81.3% with air, those were 90.7% and 87.5% with nitrogen, respectively. Color appearance showed close relation to the stability of total carotenoids during 60 days storage at varying temperatures ; $5^{\circ}C,\;25^{\circ}C\;and\;40^{\circ}C$ were 69.4%, 48.0% and 35.1%, respectively. The degradation of total carotenoids during storage could be interpreted as a first order reaction. The activation energy obtained from the Arrhenius plot was 5.03 kcal/mole. Conversely, capsaicin was very stable under storage temperatures. More than 90% of capsaicin was remained upon completion of storage. In the mean time, pH of oleoresin was increased slightly as increasing storage temperatures.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.57-62
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• 2007

Microbiological, pH, and sensory evaluations on pork tender-loins treated with potassium sorbate (PS) during storage at $4^{\circ}C$ were assessed. Treatments of 0.5-2.0% PS for 10 min effectively (P < 0.05) inhibited the growth of aerobic plate counts (APC) and gram-negative bacterial counts (GNC) compared to those of controls for 9 days at $4^{\circ}C$, respectively. Results of this investigation demonstrate that antimicrobial activity on APC and GNC in all treatments enhanced by increasing concentrations of PS during storage at $4^{\circ}C$. pH values of pork tender-loins treated with PS gradually increased by storage of 6 days at $4^{\circ}C$. Sensory data showed that 0.5-1.0% PS treatments were quite close in odor and appearance compared to fresh controls. Results indicated that pork tender-loins treated with 1.0% PS for 10 min could extend shelf-life to 9 days during refrigerated storage at $4^{\circ}C$ without adversely affecting sensory quality.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.681-688
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• 2017

This study was conducted to investigate the effect of gelatin concentration and storage on color and texture of puffer fish stock jelly. Puffer fish stock jelly was prepared by adding various amounts (2.5~10 percent) of gelatin to puffer fish stock. Color changes of puffer fish sstock jelly were also investigated during storage at $4^{\circ}C$ and $25^{\circ}C$ with varying amount of gelatin (2.5~10.0 percent). Regardless of storage temperature, the L values of puffer fish stock jelly were slightly increased, while a values of the stock jelly were negatively decreased during storage. However, L and negative b values were decreased with increasing gelatin concentration, whereas a values were increased negatively with increasing gelatin concentration. The texture profiles of puffer fish stock jelly such as hardness, springiness, cohesiveness adhesiveness, chewiness and brittleness were determined during storage at $25^{\circ}C$ and $4^{\circ}C$ at various intervals. The hardness, chewiness and brittleness were increased during storage at $25^{\circ}C$ for four days, while those of springiness and cohesiveness were decreased during storage. However, the values of all textural parameters were increased with increasing gelatin concentration in puffer fish stock jelly. Patterns of textural parameters of puffer fish stock jelly stored at $4^{\circ}C$ were practically identical to those stored at $25^{\circ}C$.