• 한국식생활문화학회지
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• 제30권3호
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• pp.370-376
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• 2015

In this study, we compared the organoleptic and other qualities of fermented milk containing 10 or 15% purple carrot extract that had either been previously fermented with Aspergillus oryzae or not fermented. Fermentation characteristics, pH, chromaticity, viscosity, viable cell counts, and sensory evaluations were measured. The pH and acid values did not differ between purple carrot extract fermented with Aspergillus oryzae and non-fermented extract. Viable cell counts were significantly higher in 15% purple carrot extract fermented with Aspergillus oryzae compared to the control after fermentation. Regarding characteristic changes, purple carrot extract fermented with Aspergillus oryzae group showed a lower red value but higher yellow value compared with non-fermented purple carrot extract due to heat-sterilization. Both fermented and non-fermented extract groups showed significantly increased viscosity compared to control. In the sensory evaluation, 15% purple carrot extract fermented with Aspergillus oryzae showed the highest score. In conclusion, addition of 15% purple carrot extract fermented with Aspergillus oryzae resulted in a superior fermented milk product.

• 한국식생활문화학회지
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• 제30권4호
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• pp.475-480
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• 2015

Jeju citrus, which contains an abundance of calcium and vitamin, was used to develop fermented citrus peel extract. A total of seven probiotic strains were applied to tangerine dermis to select the best growing bacteria in citrus peel extracts. B. longum, B. bifidum, and L. mesenteroides were found to grow best in citrus peel extract culture containing glucose, yeast extracts, peptone, and potassium phosphate. Citrus peel extract culture consisting of 1% yeast extract, 5% peptone, and 0.1% phosphate was the best environment for growth of probiotics. The pH, acidity, and viable cell numbers of these fermented extracts were measured. The initial pH level of fermented extracts with nutrients was 5.25 and dropped rapidly to 3.39 after 72 hours of fermentation. The acidity of fermented extracts increased to 4.08 % after 72 hours of fermentation, and the viable cell number in fermented extracts after refrigeration for 2 weeks was $1.3{\times}10^{10}CFU/mL$. The antimicrobial activity of citrus peel fermented extracts against Campylobacter jejuni was determined, and concentrations more than 25,000 ppm showed antimicrobial activity.

• 한국식품영양과학회지
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• 제28권1호
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• pp.107-112
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• 1999

Physicochemical properties and microflora of kimchi stew's sauce were investigated during 6 months at 13oC, 27oC and 37oC to study the changes of its quality. The final pH values in the sauce showed a slight decrease to 4.46, 4.38 and 4.21 during storage at 13oC, 27oC and 37oC, respectively. Color(L, a, b values), salinity, moisture and Aw in the sauce were decreased during storage. However, the values of brix and browning, and the amounts of total sugar, crude protein and crude fat in the sauce were increased during storage. All the reactions occurred more rapidly in the samples stored at 37oC than those stored at 27oC and 13oC. The viable cell counts of aerobic bacteria in the sauce were changed remarkably during storage, but viable cell counts of lactic acid bacteria were decreased. Yeast, mold and E. coli were not found in the above temperatures during storage. Regression analysis between sensory scores and quality characteristics showed that the ΔE value was a major quality index for the deterioration of kimchi stew's sauce. The shelf lives of sauces at 13oC, 27oC, 37oC were estimated to be 24 months, 6 months and 6 months, respectively.

• 생명과학회지
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• 제12권3호
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• pp.363-368
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• 2002

한국 민속주의 품질평가를 위해 민속주 31종을 대상으로 에탄을 함량, pH, 산도, 총당 및 환원당의 함량과 같은 특성을 조사하였다. 또한 민속주의 ATP함량은 lumitester로 측정하여 생균수와 비전하였다. 민속주의 물리.화학적 특성은 아래와 같이 확인되었다.; pH는 3.59~4.79 였고 총 산도는 4.23~16.21이였으며 총당과 환원당의 함량은 각각 0.04 ~1.13, 0.006 ~ 0.999 g/100 mL로 나타났고 ATP함량은 $10^1$~$10^{6}$ RLU범위에서 관찰되었다.

• 한국식품영양과학회지
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• 제29권5호
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• pp.854-859
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• 2000

A functional yogurt was prepared from whole milk (12%) and skim milk (2%) added with green tea and mugwort tea at 3$0^{\circ}C$ for 24 hors. The yogurt product were evaluated for acid production (pH, titratable acidity), number of viable cell, viscosity, sensory property and quality-keeping property. Addition of green tea and mugwort tea remarkably accelerated acid production of yogurt. After 24 hrs incubation, titratabel acidity of green tea and mugwort tea yogurt was 1.46% and 1.62%, respectively and was higher than that (1.30%) of yogurt made with only milk. The propagation of lactic acid bacteria was not stimulated by green tea and mugwort tea and then the number of viable cell in normal (milk) yogurt green tea yogurt and mugwort tea yogurt groups, after 24 hrs incubation, was about 7.2$\times$$10^{8}$, 7.1$\times$$10^{8}$ and 7.0$\times$$10^{8}$/mL, respectively, Viscosity of green tea yogurt was slightly lower than that of milk yogurt (1,840 cps) and viscosity of mugwort tea yogurt was slightly higher than that of mild yogurt. The overall sensory score of green tea yogurt was the best of tested yogurt. When yogurt with green tea and mugwort tea was kept at 5$^{\circ}C$ for 15 days, its quality-keeping property was relatively good.

• 방사선산업학회지
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• 제6권3호
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• pp.273-279
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• 2012

Silica hybrid silver nanoparticles showing the strong antimicrobial activity, in which nano-silver is bound to silica molecules, has been synthesized using ${\gamma}-irradiation$ at room temperature. The present study relates to an antimicrobial composition for coating fiber products comprising silica hybrid silver nanoparticles. In this study, we describe antimicrobial fiber products coated with the silica hybrid silver nanoparticles and a method of antimicrobially treating fiber products by coating the fiber products with the silica hybrid silver nanoparticles. The antimicrobial fiber products exhibited excellent antimicrobial effects. In detailed practice, when the present composition comprising nanosized silica-silver was applied to a cloth (fabric) in a concentration of $6.4mg\;yard^{-1}$, the viable cell number decreased to less than 10 cells before and after laundering, resulting in a reduction of 99.9% or greater in the viable cell number. The present composition displays long-lasting potent disinfecting effects on bacteria. Also, we investigated the toxicity of silica hybrid silver nanoparticles in rats. The skin of rats was treated with a 30 ppm nanoparticles solution ($2ml\;Kg^{-1}$) for 8 days. No toxicity was detected in the treatment. These results suggest that the fiber products coated with the silica hybrid silver nanoparticles can be used to inhibit the growth of various microorganisms.

• 한국수산과학회지
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• 제55권5호
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• pp.670-680
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• 2022

Owing to the lack of a cold-chain distribution system, most seafood is generally distributed under room temperature conditions. However the degradation of freshness during the distribution process can lead to disputes between sellers and consumers. The most widely used method for low-temperature distribution for seafood includes packaging it with styrofoam boxes and cold packs. In this study, vacuum-packed frozen fillets of four fish species of [white meat (Paralichthys olivaceus and Sebastes schlegelii) and red meat (Scomber japonicus and Scomberomorus niphonius)] were placed in styrofoam boxes with cold packs. Thereafter, changes in chemical (including pH, volatile basic nitrogen, and trimethylamine), physical (odor intensity, hardness, and chewiness), and microbial (viable cell count) characteristics of the fillets were measured during storage at 25℃. To identify the suitable method of determining freshness during the room-temperature distribution, several factors were considered, which included significant difference verification, correlation coefficients, and economic efficiency (experimental cost and time). Volatile basic nitrogen, pH, odor intensity, and viable cell count are the most rapid and accurate freshness indicators for determining freshness of frozen fish fillets during.

• Human Ecology Research
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• 제59권2호
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• pp.275-286
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• 2021

In this study, we produced kimchi with cooked Dioscorea batatas yam based on the its outstanding nutritional value, biological activity, and pharmacological action. Sliced kimchi cabbage, processed white radish kimchi (kkakdugi), and whole kimchi cabbage were prepared with 3% Dioscorea batatas, and the physicochemical and bioactivity characteristics were analyzed. In three kinds of Dioscorea batatas. The pH of the kimchi decreased and its acidity increased as the storage period was extended. The period of the maximum total viable cell count of the sliced cabbage and the processed white radish kimchi (kkakdugi) was 14 days, while the period for whole kimchi cabbage was 21 days. The period of maximum lactic acid bacteria count was 14 days for all three kinds. For physiological activities, polyphenol and flavonoid contents and DPPH elimination were highest immediately after production of the kimchi. Also, anthocyanin content increased as the storage period extended. The pH, acidity, total viable cell count, lactic acid bacteria count, and physiological activities were shown to be different according to the type of kimchi and the storage period.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권3호
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• pp.138-149
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• 2002

Plant cell culture provides a viable alternative over whole plant cultivation for the production of secondary metabolites. In order to successfully cultivate the plant cells at large scale, several engineering parameters such as, cell aggregation, mixing, aeration, and shear sensitivity are taken into account for selection of a suitable bioreactor. The media ingredients, their concentrations and the environmental factors are optimized for maximal synthesis of a desired metabolite. Increased productivity in a bioreactor can be achieved by selection of a proper cultivation strategy (batch, fed-batch, two-stage etc.), feeding of metabolic precursors and extraction of intracellular metabolites. Proper understanding and rigorous analysis of these parameters would pave the way towards the successful commercialization of plant cell bioprocesses.

• Biotechnology and Bioprocess Engineering:BBE
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• 제1권1호
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• pp.32-35
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• 1996

Amoving aeration-membrane (MAM) bioreactor was employed for the production of 2$\mu$g/mL of tissue type Plasminogen Activator (tPA)in serum free medium from normal human fibroblast cells. This system could maintain high cell density for long periods of steady state conditions in perfusion cultivation. Under normal operating condition, shear stress was as low as 0.65 dynes/$\textrm{cm}^2$ at the agitation speed of 80 rpm. Even though cell density gradually decreased with increasing agitation speed, tPA production increased linearly with increasing shear stress within a moderate range. This culture system allowed production of 2$\mu$g tPA/mL while maintaining a high cell denisty of 1.0$\times$107 viable cell/mL.