• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.117-123
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• 2000

The object of this work is to improve the maintenance of bioluminescence from stored Photobacterium phosphoreum in a view of developing continuous monitoring system for pollutants. The long-term experiments were performed to determine the effect of storage temperature and immobilization on the maintenance of bioluminescence and viability of P. phosphoreum. A naturally luminescent bacterium, P. phosphoreum was starved in 2.5% Nael solution at $20^{\circ}C$, $4^{\circ}C$, -$20^{\circ}C$ and -$70^{\circ}C$ for 30 days. In vivo luminescence was measured by luminometry, and total cell concentrations and concentrations of culturable and viable cells were determined by acridine orange staining, dilution plate counting, and direct viable counting, respectively. The bioluminescence emission from cells stored at 4De was maintained up to 10 days while those with starved cells at other temperature ranges decreased to background level within 3 days. In terms of viability of cells, concentrations of cells stored at $20^{\circ}C$ were rapidly decreased as a result of cell lysis, leading to a drop in culturable and viable counts while cells stored at $4^{\circ}C$ was shown viable but nonculturable state during starvation. With immobilized cells on strontium alginate, the bioluminescence showed higher maintenance than free cells and decreased with count number of nonculturable cells.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.107-107
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• 2003

고품질 쌀 생산을 위하여 우리나라의 농가 및 미곡종합처리장의 벼 수확후 품질관리 현황 실태를 조사하여 일본, 미국, 중국 둥의 현황과 비교하였다. 중국의 경우 벼 수확은 대부분 인력에 의존하고 있으며, 일본은 산물형 콤바인 그리고 미국은 대형산물 콤바인에 의한 적기수확을 하고 있다. 우리나라의 경우에는 콤바인이 부족하고 벼 수확시기는 콤바인 운영자의 일정에 따라 결정되고 있으며 습논, 소면적 재배 논은 수확이 늦어져 적기 수확이 못되고 있는 실정이다. 한편 일본은 라이스센터, 컨트리엘레베타, 드라이스토아 등의 지원으로 적기 수확이 가능하고 건조기 건조율도 90%이상 2단계 상온 통풍체계로 수분함량 14.5~15.5%를 유지하고 있다. 우리나라를 제외한 일본, 중국, 미국의 저장시설은 대부분 대형저장 사이로에서 품종별, 산지별, 등급별로 구분한 저온저장 시스템을 갖추어 품질을 유지하고 있었다. 또한 도정시설도 고품질 도정시설을 완비하고 있으며 제현이나 정미과정에 색채선별기, 금속검출기, 활성화 장치 및 입형분리기 등을 통하여 불완전미가 제거하는 등 수확후 관리에 철저를 기하고 있다. 쌀의 등급화 및 유통과정를 보면 일본, 중국, 미국 등은 대부분이 품종, 산지 및 등급별로 브랜드화 하여 차별화 된 가격으로 판매되고 있으며 포장지에 쌀에 대한 정보를 최대한 표시하여 소비자가 선택하는데 도움이 되게 하여 유통되고 있다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.250-254
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• 2005

본 연구는 육성기, 비육기 사료내 라이신 수준이 재래흑돼지 냉동육의 저온저장중 품질특성에 미치는 영향을 구명하고자 실시하였다. 드립감량은 재래흑돼지육이 개량종 돈육보다 낮았으며(p<0.05), TBARS는 저장 7일에 저라이신 수준의 개량종 돈육이 고라이신 수준의 개량종 돈육보다 높았으며(p<0.05), 저장기간 동안 재래흑돼지육과 개량종 돈육간에 차이가 없었다. L 값은 저장5일부터 재래흑돼지육이 저라이신 수준의 개량종 돈육보다 높았고(p<0.05), a 값은 재래흑돼지육이 개량종 돈육보다 유의적으로 높았다(p<0.05). b 값은 재래흑돼지육이 고라이신 수준의 개량종 돈육보다 높았다(p<0.05). 포화지방산은 저라이신 수준의 재래흑돼지육이 가장 높았으나(p<0.05), 불포화지방산과 불포화지방산/포화지방산 비율은 가장 낮았다(p<0.05). 단가불포화지방산/포화지방산 비율은 저라이신 수준의 재래흑돼지육이 고라이신 수준의 개량종 돈육보다 유의적으로 낮았다(p<0.05). 따라서 이상의 결과를 종합해 보면 재래흑돼지육이 개량종 돈육보다 보수력, 육색이 우수하였으며, 저라이신 수준의 사료를 급여시 재래흑돼지육의 포화지방산은 증가하였으나 불포화지방산은 감소하였다.

• Food Science and Preservation
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• v.18 no.4
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• pp.612-619
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• 2011

Cronobacter sakazakii has been isolated from a wide range of environmental sources and from several foods of animal and plant origin. The objective of this study was to determine the resistance of C. sakazakii (ATCC 12868, ATCC 29004, and ATCC 29544) in cold, cold-freeze thaw, cold-acid, and cold starvation-freeze thaw stress. The number of C. sakazakii decreased to 1 log CFU/mL at $5^{\circ}C$ (cold storage) for 10 days. When C. sakazakii was cultivated at a low temperature ($13^{\circ}C$), the population of C sakazakii ATCC 12868 and 29004 increased to $10^9$ CFU/mL, and the population of C. sakazakii ATCC 29544 increased to $10^8$ CFU/mL. For C. sakazakii ATCC 12868 and 29004, the cold-adapted cells ($5^{\circ}C$ 24 hr) decreased by 4 log CFU/mL, and the low-temperature-cultivated cells ($13^{\circ}C$) decreased by 0.5 log CFU/mL. In this study, low-temperature cultivation enhanced the freeze-thaw cross-resistance due to the metabolic changes in the cells. Cold stress ($5^{\circ}C$ 48 hr, $13^{\circ}C$ cultivation) enhanced the cold-acid cross-resistance. The cold-starved cells in the sterilized 0.1% peptone water enhanced the freeze-thaw cross-resistance with significant differences (p<0.05). Therefore, the increased tolerance of the cold-adapted or low-temperature-cultivated C. sakazakii cells to freeze-thaw, acid, or starvation suggests that such environments should be considered when processing minimally processed foods or foods with extended shelf life.

• Horticultural Science & Technology
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• v.17 no.4
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• pp.467-469
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• 1999

This study was conducted to examine the changes of nutritive substances in the edible potato varieties ('Superior', 'Atlantic', 'Irish Cobbler', 'Dejima') during storage under low temperature condition($4^{\circ}C$, 85-90% RH) from January to May. The items examined in this experiment were moisture, free soluble sugars, starch and vitamin C. The contents of starch and vitamin C decreased with increasing storage period. The rates of decrease in starch and vitamin C contents were high in February and low after that. The contents of moisture and free soluble sugars did not show a constant tendency during storage period. The contents of glucose and fructose were the highest in February and March. Among the four varieties, 'Superior' contained highest vitamin C, free sugar, and moisture, while 'Atlantic' contained the highest starch.

• Food Science and Preservation
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• v.10 no.1
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• pp.6-10
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• 2003

The objective of this study was to investigate the effect of browning inhibitor and vacuum packaging on minimally processed sweet pumpkin. The browning inhibitor were lo/e of ascorbic acid, citric acid, NaCl, MgCl$_2$and their combination. For the minimal processing, sweet pumpkin was sliced and strip-cut followed by dipping in the solution of browning inhibitor. Effective browning inhibitors fer slice sweet pumpkin were ascorbic acid, NaCl and MgC1$_2$, and those fer thin strip were combination and ascorbic acid. The hardness of minimally processed sweet-pumpkin repeated increasing and decreasing and decreased in the final of storage. However the change pattern of hardness was different according to cutting method. Magnesium chloride treatment was generally high grade on sensory characteristics. Sweet pumpkin treated with citric acid was distinguished on carbon dioxide generation and oxygen exhaustion.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.115-120
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• 2004

This study was carried out to investigate the effect of the scalding temperature at slaughtering process on meat quality and storage properties of chicken. The yellowness (b$\^$*/ value) of skin decreased at high scalding temperature (65-67$^{\circ}C$) and WHC (water holding capacity) increased from 67.04％ at low temperature (53-55$^{\circ}C$) to 69.26％ at high temperature. WBS (Warner-Bratzler Shear force) significantly increased from 1.70kg/0.5inch$^2$ to 2.54kg/0.5inch$^2$ as the scalding temperature increased (p＜0.05). TBARS (Thiobarbituric Acid-Reactive Substance) values were 0.25mgMA/kg at low temperature, 0.24mgMA/kg at middle temperature (59-61$^{\circ}C$) and 0.27mgMA/kg on 3 days of storage. Total aerobic counts (TPC) were 4.99 logCFU/mL at low temperature, 4.88 10gCFU/mL at middle temperature and 4.05 logCFU/mL. Although TPC was decreased as the scalding temperature increased. The detection rate of feather at carcass inspection was low as the scalding temperature increased and the detection rate of large feather (＞lcm) was not significantly different between middle temperature and high temperature. Exposed flesh was severe as the scalding temperature increased. In conclusion, meat color and physical properties of chicken were acceptable when the carcasses were scalded at low temperature, but they were microbiologically susceptible and uneasy to remove the feather. The yellowness (b$\^$*/ value) of skin decreased at high scalding temperature, and total aerobic counts (TPC) were decreased as the scalding temperature increased, and easy to remove the feather.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1476-1480
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• 2016

Anti-microbial effects of the medium extracts from three different lactic acid bacteria (LB1, Lactobacillus acidophilus; LB2, Lactobacillus casei; LB3, Lactobacillus sicerae) were investigated. Three different extracts of lactic acid bacteria media (ELAM) did not show significant changes in pork loin quality after 3 and 14 days of cold storage such as general contents, colors, pH, and TBARS. To determine anti-bacterial activity of three ELAM, three pathogenic bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus) were obtained and incubated with ELAM-absorbed paper discs. ELAM of LB2 and LB3 showed significantly larger bacterial growth inhibitory zones compared with that of LB1 (P<0.05). When the pathogenic bacteria inoculated in pork loin with three ELAM, total microbial contents of pork loin treated with ELAM of LB3 after 14 days of cold storage showed significantly lower microbial contents compared to those of control, LB1 and LB2 (P<0.05). In conclusion, ELAM of LB3 derived from L. sicerae had the most effective pathogenic bacteria inhibitory activity on agar and pork loin. This is the first result to report the antibacterial effect of L. sicerae. If the safety and toxicity characteristics of L. sicerae are further investigated, this new lactic acid bacterium would have potential as an effective and nature-friendly food preserving agent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.101-108
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• 1984

In order to study the optimal conditions of processing and storage for boiled and dried anchovy (Engraulis japonica) with high protein digestibility, the contents of trypsin indigestible substrate (TI) and in vitro apparent protein digestibility were determined. Peroxide value (PoV), TBA number and nonenzymatic brown pigments, that accounted for important antinutritional factors, were also measured and confirmed the relationship between those factors and formation of TI or in vitro protein apparent digestibility. The results were as follows; Samples boiled for 5 minutes showed the lower content of TI than the other samples boiled for 0.5 min. or 1 min. Hot air dried products had a lower TI content in comparison with the other dried ones such as sun dried or freeze dried products. It was revealed that the lower temperature ($8{\pm}1^{\circ}C$) did not affect to a great degree of forming TI and falling in vitro digestibility comparing to high temperature ($26{\pm}1^{\circ}C$) during storage. The lowest TI content (0.173 mg/g solid) was noted in the samples for 5 minutes and then sun drying after 56 days storage at $9{\pm}1^{\circ}C$. A rapid decrease of in vitro protein digestibility occurred within 0.5 min. of boiling and showed the value $85.3\%$. Freeze dried samples possessed the highest in vitro protein digestibility ($85.9\%$), when compared to sun dried or hot air dried products. Fat oxidation and nonenzymatic browning were proceeded with the various boiling times, drying methods and storing temperatures. It was noted that boiling for 5 minutes and freeze drying accelerate the fat oxidation significantly. More nonenzymatic brown pigments was developed in samples boiled for shorter time (0.5 min.) and that stored at high temperature ($26{\pm}1^{\circ}C$) than the other products. Therefore, fat oxidation and nonenzymatic browning assumed to be a major inhibitory reaction in enzyme digestion and those might be an important role in forming TI in boiled and dried anchovy products during processing and storage.

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.29-41
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• 1978

This study aims to brew apple wine containing lower concentration of alcohol by fermentation and to retain $CO_2$ gas in apple wine, and investigation for the possibility of storage at room temperature was performed. A Saccharomyces sp. was proved to be acceptable for production of base wine as its higher fermentation rate at $20{\sim}25^{\circ}C$. However, B-2 was most reasonable for post-fermentation of apple wine as this strain strongly ferments sugars at low temperature $(4^{\circ}C)$. The yield of apple juice increased by maceration of apple pulps. The yield was about 5 % more than that of the unmacerated juice, whereas acid content was decreased by 10% compared with control. When stored apple wine containing 9% alcobol was introduced $1{\sim}3%$ sucrose at $7{\sim}8^{\circ}C$ for 100 days or more, the $CO_2$ pressure of apple wine in bottle shows $3kg/cm^2$ by bottle-pressure meter. It showed good storage of the wine at room temperature. $CO_2$ gas pressure in apple wine containing 6% alcohol, $5{\sim}10%$ hop extract, and 2% sugar was $2kg/cm^2$, he result also showed possibility of storage. Whereas 6% concentration of alcoholic apple wine without hop extract caused unusual fermentation during storage at the same condition. The desirable conditions for high quality apple wine should have $CO_2$ pressure of $2kg/cm^2$ or more and should be added $1{\sim}2% sugar to base wine. From these results, it can be concluded that the brewing of lower alcoholic apple wine is possible.