• Food Science and Preservation
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• v.10 no.1
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• pp.23-27
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• 2003

This study was conducted to develop the corrugated fiberboard box which is suitable to pre-cooling and low temperature distribution of chinese cabbage Consider from a cooling performance viewpoint, the folding type box with 5.4% vent hole ratio was most efficient for fast cooling and even temperature distribution in the packaging box. At the end of storage periods, the compressive strength of the folding type box was less than the bliss type box. However, the compressive strength of the folding type box after storage was higher than required safety compressive strength for long term storage. So the folding type box was considered to have no problems toy practical use. The shelf-life of the chinese cabbage packaged with the developed box was 6∼7 days which was 2∼3 days longer than usual packaging.

• Journal of Life Science
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• v.26 no.12
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• pp.1438-1445
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• 2016

Yeast can be post-contaminated by the equipment, producer, or air, and this can degrade yogurt quality. This study aimed to demonstrate the yeast inhibiting effect in fermented milk by adding Lactobacillus paracasei and Lactobacillus rhamnosus along with current fermenting lactic acid bacteria such as Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. A certain amount of yeast was added to fermented milk samples that were soon after stored at variable temperatures, and the number of yeast cells was counted periodically. The swelling phenomenon caused by the gas produced by the yeast in fermented products was also observed. In the two experiments, compared to the control, the L. paracasei- and L. rhamnosus-added-groups showed much slower rate of yeast appearance and lower frequency of swelling phenomena. This suggests that using a mixture of L. paracasei and L. rhamnosus in fermented milk inhibits the growth of yeast. Furthermore, if the products are stored at $10^{\circ}C$, post-acidification is rarely seen in the experimental group compared to the control group. This means that the organoleptic flavor can be kept consistent from the production day till the expiration day, resulting in improved organoleptic quality for customers. In other words, the use of L. paracasei and L. rhamnosus in fermented milk will result in the following positive effects: improvement in storage stability by delaying yeast appearance, increase in quality consistency by inhibiting post-acidification, and improved organoleptic quality by enhancing texture and flavor.

• Food Science and Preservation
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• v.15 no.3
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• pp.377-384
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• 2008

The gamma irradiation process was performed to prolong a shelf-life of peaches and the effects of a gamma irradiation on the nutritional, physiochemical and sensory characteristics of peaches were evaluated during a post-irradiation storage at $4^{\circ}C$ and $25^{\circ}C$. Nutritional, physiochemical and sensory characteristics of peaches were stable at 1 kGy of an irradiation, a recommended dose for fruits and vegetables by CODEX, and the viable cell counts of contaminated microorganisms were reduced by 2 decimal reduction, at this dose. After a 1-week storage at ambient condition, the microbiological quality of the 1 kGy irradiated peach was stable, while all the non-irradiated peaches were deteriorated Furthermore, cold storage enhanced the shelf-life of the gamma irradiated peach and the nutritional and physiochemical characteristics of the peaches were comparatively stable up to 6 weeks. Right after gamma irradiation, the sensory evaluation results were not different in any of the samples, and the sensory quality of the irradiated peaches was adequate for a 4-week storage at $4^{\circ}C$. Our results suggested that gamma irradiation at 1 kGy can be used to enhance the shelf-life of peach without a significant loss in the quality attributes, especially upon cold storage after radiation treatment.

• Food Science and Preservation
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• v.15 no.5
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• pp.648-655
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• 2008

A gamma irradiation process was applied to prolong the shelf-life of grapes and changes in microbiological, physicochemical, nutritional, and sensory characteristics were investigated during 6 weeks of post-irradiation storage at $4^{\circ}C$ and $25^{\circ}C$. Physiochemical characteristics of grapes such as total sugar content, pH, titratable acidity, and anthocyanine content, were stable after 1 kGy of irradiation, a dose recommended by CODEX for fruits and vegetables. The viable cell counts of contaminating microorganisms were reduced 1-2 logs by this radiation dose. After 6 weeks of storage at $4^{\circ}C$ the microbiological quality of irradiated grapes was stable, but all non-irradiated grapes had deteriorated. Whether or not grapes were irradiated, weight loss rapidly increased after 2 weeks of storage at $25^{\circ}C$, whereas weight loss was delayed by storage at $4^{\circ}C$. Immediately after gamma irradiation, the sensory evaluation results did not differ between samples, and the sensory quality of the irradiated grapes remained acceptable for over 6 weeks of storage at $4^{\circ}C$. The results suggest that 1 kGy of gamma irradiation does not detrimentally affect the nutritional or physical characteristics of grapes, especially when cold storage follows radiation treatment. In conclusion, a combination of gamma irradiation and cold storage prolonged the shelf-life of grapes by 6 weeks.

• Food Science and Preservation
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• v.18 no.1
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• pp.1-6
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• 2011

Kochujang-gulbi, a Korean traditional food, was prepared with kochujang and freeze-dried gulbi slices. Kochujang-gulbi was treated with high hydrostatic pressure (200, 400 and 600 MPa) and gamma-irradiation (7, 10, 20 and 30 KGy) to improve its quality and shelf-life. The pH of high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples did not significantly different compared to that of control. However, Hunter L value slightly increased, and Hunter a and b values decreased by high hydrostatic pressure and gamma-irradiation treatment. During storage, the pH and color of high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples did not significantly changed. The VBN and TBA level decreased by the increase treatment of high hydrostatic pressure and then slowely increased during storage. The VBN and TBA level of kochujang-gulbi samples treated by the strong gamma ray emission slowely increased during storage. In particular, gamma-irradiation treatment was very effective to sterilize microorganisms when compared to that of high hydrostatic pressure in kochujang-gulbi products. In addition, the high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples shown significantly lower total viable cell number than control for the 20 days of storage at room temperature with retort pouch packaging.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.247-251
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• 2002

This study was carried out to investigate the keeping quality of market milks collected from several dairy processing companies. Microbiological, chemical, and sensory properties of Intra-high temperature(UHT) treated milks stored at 5, 10, 15t were evaluated during the storage of 154days. No significant difference during the storage was shown in bacterial counts, pH and titratable acidity. Standard plate count(SPC) was remained less than 20,000 cfu/ml after 15 day storage at 5, 10, 15$^{\circ}C$. Also, Psychrotrophic bacterial count and Coliform count were not detected or detected at low level. The pH ranged from 6.55 to 6.83 and the titratable acidity ranged from 0.13% to 0.16%. In sensory evaluation, UHT milks showed normal flavor until 10days, but thereafter off-flavor was slightly developed. Consequently, UHT milks remained in good quality when stored at 5$^{\circ}C$,10$^{\circ}C$t until 15days except sensory properties. According to this experiment, the shelf-life of UHT milk can be extended to 10 days, even though maintaining the storage temperature strictly below 10 t in milk market is not easy.

• Journal of Dairy Science and Biotechnology
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• v.36 no.4
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• pp.220-225
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• 2018

The purpose of this study was to investigate the effect of ultrasonic treatment during probiotics production process on the shelf life and the survival rate. Once Lactobacillus plantarum and Bifidobacterium longum were cultured in edible culture medium, ultrasonic treatment was performed at 100 Hz for 1, 2, 5, 7, and 10 minutes. Ultrasonic-treated L. plantarum HY7715 and B. longum HY8001 were centrifuged, mixed with a cryoprotectant, and lyophilized. The prepared lactic acid bacteria powder was individually packaged. After 6 months, viable cell counts were measured separately under cold storage and room temperature. In vitro digestion experiments were performed to determine the survival rate at digestive tract. As a result, it was observed that shelf life and survival rate were increased compared to untreated control group.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.121-126
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• 2005

The changes in quality characteristics and shelf-life of vacuum-shrink packaged Bierschinken after stuffing in fibrous casing and stored at 5 and $10^{\circ}C$ were investigated The total aerobic plate count (APC) of Bierschinken was initially <2.00 $log_{10}CFU/cm^2$, however increased gradually over storage period The APCs of Bierschinken maintained at the level of 4.86 and 5.13 $log_{10}CFU/cm^2$ after 35 days at 5 and $10^{\circ}C$, respectively. pH tended to decrease with the extension of storage period The values of TBA and VBN tended to increase with storage time, of which trend was pronounced at $10^{\circ}C$ rather than at $5^{\circ}C$. According to the sensory evaluation, Bierschinken had the marketing value till 28 days irrespective of storage temperature. The shelf-life of Bierschinken tested might be preferentially restricted by the occurrence of off-odor and off-flavor at the end of storage period.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.1017-1020
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• 2010

최근 국산 농산물의 수요급증과 더불어 소비자들은 안전한 제품의 요구가 높아지고 있다. 이러한 요구에 맞는 제품 개발의 일환으로 미생물 제어가 된 고춧가루 포장제품의 품질향상을 위한 천연항균 물질 소재를 탐색하여 제품개발에 응용하였다. 천연물과 한방재료 중 고춧가루 제품에 적합한 소재를 스크리닝하여 항균물질을 탐색하였으며 고춧가루 제품 패킹에 응용하였다. 천연물 항균제의 개발 원칙은 산취 등 이취가 없어야 하며, 제품에 응용할 수 있는 용해성이나 믹싱의 효과를 높이도록 공정을 최적화 하였다. 또한 최종 천연물 항균제의 형태는 분말 형태로 개발하였다. 천연물에 대한 항균활성은 paper disk test를 통하여 비교하였으며, 항균력이 가장 우수한 소재는 황금추출물이었다. 또한 이들 추출물과 비타민 $B_1$ 인산염의 영향을 함께 비교하였다. 이 천연물 소재 추출물로 개발한 항균물질에 대한 효과는 일반세균, 대장균 검사를 실시하였다. 제품의 안정성 확보 및 유통기한 연장 가능성을 실험한 결과, 일반세균은 $1.0{\times}10^5$cfu/g, 대장균군은 $1.0{\times}10^2$cfu/g, 대장균은 불검출 되었다. 이들 추출물의 항균제 개발과 더불어 다양한 식품에 천연물 항균제로서의 적용 가능성을 모색하고자 하며, 안전한 천연 항균제 개발에 대한 기초 자료를 제공하는 기초 연구를 하고자 하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.349-357
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• 2019

The effect of entrapping isothiocyanates extracted from horseradish root by microencapsulation on the shelf life of Myeongran jeotgal was evaluated. The total viable cell count of Myeongran jeotgal reached $10^7CFU/g$ (initial decomposition level) on days 43 and 45 of treatment with 1.0% and 2.0% microcapsules (4.0 mg/mL), respectively, compared with day 21 of storage at $5^{\circ}C$ as the control treatment. The proteolytic bacterial counts of Myeongran jeotgal treated with 1.0% and 2.0% microcapsules were $2.0{\times}10^5$ and $9.5{\times}10^4CFU/g$, respectively, with 2 and 3 log reductions compared with the control count ($1.1{\times}10^7CFU/g$) on day 33 of storage at $5^{\circ}C$. The total volatile basic nitrogen (TVB-N) level reached 30.0 mg% (initial decomposition level) on days 47 and 48 of treatment with 1.0% and 2.0% microcapsules, respectively, compared with day 33 of storage at $5^{\circ}C$ as the control. Based on the sensory evaluation, the freshness of Myeongran jeotgal treated with 1.0% microcapsules was best compared with the other treatments. Based on the total viable cell count, TVB-N and sensory evaluation, the shelf life of Myeongran jeotgal treated with 1.0% microcapsules was extended by 22, 16 and 15 days, respectively, compared with the control at $5^{\circ}C$.