• Journal of Dairy Science and Biotechnology
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• v.36 no.3
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• pp.178-185
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• 2018

Kefir, which originates in the Caucasian mountains, is a cultured milk beverage produced by a combination of acidic and alcoholic fermentation. Kefir products are commonly used as food vehicles to deliver health-promoting materials including kefran and lactic acid bacteria to consumers. The aim of this study was to develop a freeze-dried starter culture without yeast and assess the suitability of kefir-like dairy products for the growth of lactic acid bacteria and the acidification of milk. Pasteurized whole milk (SNF 8.5%) stored at $25^{\circ}C$ was aseptically inoculated with starter cultures (0.002% w/v); it was kept at $25^{\circ}C$ until the pH attained a value of 4.6. Ten grams of the kefir-like product sample was diluted with 90 mL of 0.15% peptone water diluent in a milk dilution bottle, followed by uniform mixing for 1 min. Viable cells of Lactobacillus species were enumerated on modified-MRS agar (pH 5.2), with incubation at $37^{\circ}C$ for 48 h. Viable cells of Lactococcus species were enumerated on M17-lactose agar, with incubation at $32^{\circ}C$ for 48 h. The pH attained a value of 4.6 after fermentation for 9 h 30 min (Starter 1), 9 h 45 min (Starter 2), and 12 h (Starter 3). The viable cell count of Lactobacillus sp. and Lactococcus sp. was initially $10^5{\sim}10^6CFU/g$; it increased significantly to $10^9CFU/g$ after 12 h of incubation. During the storage of the kefir-like products at $4^{\circ}C$ for 1 4 days, the total viable cell numbers were unchanged, but the pH decreased slightly. The consistency of the kefir products increased gradually during the storage. The organoleptic properties of the kefir products fermented using the new starter culture are more desirable than those of commercial kefir. These results suggest that the newly developed starter culture without yeast could be suitable for kefir fermentation.

• 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.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.130-138
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• 1986

In order to obtain the basic data for development of raw pepper homogenates as instant spice, effects of preservatives, packaging materials, storage temperature and period on chemical components of raw pepper homogenates were investigated during storage after sealing up. The results are as follows: 1. Raw pepper homogenates added 15% sodium chloride was effective prominently than raw pepper homogenates on residual contents of acidity, capsanthin and capsaicin. 2. P. V. D. C film was effective than P. E film in sealing of raw pepper homogenates. 3. Decomposition of capsanthin was exceeded at high temperature during the sealed storage of raw pepper homogenates and decomposition of capsaicin was accelerated at initial stage of storage and also it was decreased prominently by adding of sodium chloride. 4. Decomposition of vitamin C during the storage was exceeded at high temperature and it was prominently suppressed by adding of sodium chloride. 5. Increase of total viable cell count and lactic acid bacteia count was prominently suppressed by adding of sodium chloride and its difference for storage temperature was disregarded.

• Food Science and Preservation
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• v.22 no.5
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• pp.666-673
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• 2015

The quality characteristics of kimchi with Artemisia annua extracts (1~2%; extracted with water or 70% ethanol), including the pH, acidity, reducing sugar content, total viable cell and lactic acid bacteria cell count, and sensory parameters, were investigated at 10 and $15^{\circ}C$ for 20 days during aging. The pH, acidity, reducing sugar content, and lactic acid bacteria count of kimchi with Artemisia annua extract rapidly increased upto the 4~6th day, increasing slowly thereafter. The quality characteristics did not vary between kimchi with and without the extract. The optimal aging time for kimchi with the extract was 10 days at $10^{\circ}C$. The results of the sensory evaluation showed that kimchi with 1% Artemisia annua extract was superior to kimchi with 2% Artemisia annua extract; in particular, the color and taste of the latter were found to be black and bitter, respectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.67-73
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• 2022

The food cold chain refers to a technology and distribution supply chain applied to maintain a constant temperature suitable for the product from production (harvest) to delivery to consumers. In particular, in Korea, the insulation material used in the food cold chain is mostly EPS (Expanded Polystyrene), which is used as a transport container for various food cold chains. However, according to the government's eco-friendly policy, companies charge environmental contributions to the use of EPS, but due to its low price and convenience of handling, it is still used as a container for delivering food. In this study, in order to measure the domestic delivery environment of general refrigerated foods, changes in impact, temperature, and humidity during transport of the EPS packaging system containing foods and ice pack refrigerants were measured. As a result, there were 2?3 sections in which a high impact force of 40 G or more was generated during transport. This can cause damage to the product and EPS container. The difference in temperature and humidity changes by parcel transport routes is more than 30%, so it is necessary to present accurate standards for the domestic cold chain distribution environment. As a result of microbial experiments. the transportation period had a dominant effect on the increase in total viable count and E. coli count.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.522-528
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• 2018

Objective: This study evaluated inclusion of buckwheat silage to the diet of growing lambs in terms of meat quality as compared to maize silage. Methods: Buckwheat, rich in total phenols (TP, 33 g/kg dry matter [DM]), was harvested at the end of the milk stage and ensiled in 40 kg plastic bags after wilting (294 g/kg silage DM). A total of 18 growing lambs ($21.6{\pm}1.2$) were individually fed isonitrogenous and isoenergetic total mixed rations (TMR) for 75 d that either contained buckwheat or maize silage at DM proportions of 0.50. At the end of feeding trail all lambs were slaughtered to assess carcass characteristics and meat quality. Results: Buckwheat silage increased (p<0.01) the DM intake of lambs as compared to maize silage, but had no effects (p>0.05) on live weight gain and feed efficiency. Carcass weight, dressing percentage, meat pH, water holding capacity, cooking loss, shear force ($kg/cm^2$), and total viable bacteria count of meat did not differ (p>0.05) between the treatments. However, TP content of meat increased (p<0.001) by feeding buckwheat TMR. Feeding buckwheat TMR also decreased (p<0.05) the b* values of meat. Conclusion: The results provide that buckwheat silage is palatable and could successfully include TMR of growing lambs with no adverse effects on performance, carcass and meat quality. Additionally, feeding buckwheat silage to lambs offers increased TP in meat.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.1
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• pp.11-19
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• 2022

This study provided basic data for the commercialization of healthy functional beverages by examining the physicochemical characteristics, nutrient content, and microbiological safety of onion peel beverage. The total acid of onion peel beverage was 0.12 mg/g and the pH was 6.07. According to the storage period, the total acid decreased and the pH increased in all temperature ranges(25℃, 35℃, and 45℃). After 30 days of storage, it showed 0.06 mg/g in all temperature sections and maintained the pH 7 range. The total phenol content, which is a nutritional component of onion peel beverage, was 0.93 mg/g, flavonoid content was 0.25 mg/g, and quercetin content was 0.17 mg/g. The flavonoid content decreased according to the storage period, and in the case of storage temperature of 25℃, it contained 50% content up to 120 days of storage, but in the case of 35℃ and 45℃, it had a flavonoid content up to 90 days and 30 days, respectively. In the case of quercetin, a residual rate of about 50% was shown for 150 days of storage at 25℃ and 35℃. In the case of 45℃, it decreased to 35% at 30 days of storage. On the other hand, onion peel beverage maintained a viable cell count of less than 5 CFU/mL for 150 days of storage, and no coliform group was detected. As a result of analyzing the quality characteristics of onion peel beverage according to storage period, quality stability was confirmed in physicochemical characteristics and microbiological safety. Research on changes in biological activity according to low-temperature distribution or storage period is necessary.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1323-1328
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• 2000

Bovine colostrum, which contains a large quantity of immunoglobulins, is indispensable for newborn animals. The establishment of a new procedure for preserving colostrum without losing the immunological activity is significant. We examined the effect of high hydrostatic pressure treatment (100~500 MPa) on the preservability and the immunochemical activity of bovine colostrum. When high hydrostatic pressure treatment was 300 MPa or more, the increase of the total viable count, coliforms and psychrotrophic gram-negative bacteria was suppressed effectively. In particular, the number of coliforms in colostrum treated at 300 MPa or more hardly increased for 35 days at $4{^{\circ}C}$. At 400 MPa or more, both gelling of the colostrum and denaturation of immunoglobulins were observed. However, if the pressure was 300 MPa, immunoglobulins were scarcely influenced and the neutralizing titers against the bovine coronavirus did not decrease. Therefore, it was suggested that 300 MPa was the best pressure for good preservability of colostrum without reducing the immunochemical response.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.219-224
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• 1992

The changes of yeast population were investigated in Mul-kimchi containing 3% salt, fermented at $15^{\circ}C$. The total viable count increased to the maximum at the optimum ripening period and then decreased rapidly. Among twenty-nine strains isolated at the optimum ripening period, the yeasts of genus Saccharomyces were predominant. The growth of five strains, Saccharomyces saitoanus Y17, Saccharomyces capensis Y29, Saccharomyces chevalieri Y13, Kluyveromyces fragilis Y2, Torulopsis candida Y9, was measured in mixed culture with each selected lactic strains, hctobaczllus plantarum Lp2, Pedzococcus pentosaceus PI, Leuconostoc mesenteroides Lu5. The results indicated that all the yeasts tested were inhibited significantly by lactic strains, however the sensitivity of yeast strains varied greatly.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.2
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• pp.259-267
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• 1998

Typical characteristics of Mejus must be understood to get the basic data for setting up mass production system of traditional fermented soybean products. One hundred and twenty one Mejus were collected from various places and analyed. Most of shapes were rectangular and some were spherical, conical, cylindrical and doughnut types. The weight of Mejus was 0.4~4.2kg. Chemical analysis showed: moisture content, 9.73~58.22% ; pH, 4.95~8.15; acidity, 0.6~3.8% ; soluble protein content, 4.45~12.31%; soluble sugar content, 0.82~10.95%. Enzyme assay showed: $\alpha$-amylase activity, 5.0~874.2 units/g; $\beta$-amylase activity, 0.02~27.74units/g; acidic protease activity, 31.3~225.1unts/g; lipase activity 1.0~53.0units/g. Total viable cells were 3.72$\times$107~1.35$\times$1010cfu/g, and yeast and mold count 6.46$\times$104~8.91$\times$106cfu/g. respectively. $\alpha$-Amylase activity of a traditional Meju from Incheon showed the highest activity of 732.8 units/g(interior section) and 823.2units/g (exterior section). $\beta$-Amylase activity was the highest{3.57 units/g (interior sectin) and 4.25units/g (exterior section)} in Meju from Chunbuk. Acidic protease activity was the highest in sample from Seoul, whereas traditional Meju from Kyongnam showed the highest activity of 21.5units/g(interior section) and 37.5units/g(exterior sectin).