• Asian-Australasian Journal of Animal Sciences
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• v.1 no.4
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• pp.185-187
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• 1988

A total of 22 energy balance trials were done for calves fed a liquid milk replacer, calf starter and second cut mixed hay during weaning period. Milk replacer supplied 50% of the total dietary energy, calf starter 42% and hay 8% Live weight of calves averaged 64.6 ($S.D.{\pm}7.8$) kg and daily gain 0.54 (${\pm}0.22$) kg. The metabolizability of gross energy averaged 0.751. A regression was calculated relating energy retention (ER, $kJ/kg^{0.75}$) to the intake of metabolizable energy (IME, $kJ/kg^{0.75}$): $$ER=0.69({\pm}0.09)IME-395,\;r=0.888,\;P<0.01,\;S.E.{\pm}7.1$$. Metabolizable energy for maintenance (MEm) was calculated to be $572kJ/kg^{0.75}$ when ER = 0. The amount of IME over MEm for an individual animal (MEg, $kJ/kg^{0.75}$) was regressed on average daily gain (ADG, kg) by the method of regression through the origin: $$MEg=364({\pm}55)ADG,\;r=0.634,\;P<0.01,\;S.E.{\pm}12$$. The amount of ME required for maintenance and growth was estimated to be $936kJ/kg^{0.75}$.

• Food Science and Preservation
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• v.24 no.7
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• pp.1034-1042
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• 2017

The quality characteristics of Yakju and survival rate of yeast were investigated by modifying the drying method for the cold adapted yeast strain Saccharomyces cerevisiae Y297 (SCY297). Viability and fermentation characteristics of the freeze-dried, air blast-dried, and liquid SCY297 cultures were compared after storing them at $25^{\circ}C$. In addition, 5% skimmed milk, ${\alpha}$-lactose, or trehalose was added as a protective agent for examining the effects of drying methods. During the 15-week storage period, the liquid and freeze-dried SCY297 cultures containing a protective agent showed a survival rate of 80%. However, the air blast-dried SCY297 culture showed 80% survival rate only in the skimmed milk supplemented group. Compared to the untreated cells, the acidity and amino acidity of Yakju prepared using freeze-dried or air blast-dried cultures of SCY297 increased by 2 fold and 5.7 fold respectively, while the alcohol content decreased by 5.07%. Compared to the untreated cells, the pH and amino acidity of Yakju prepared using the liquid culture of SCY297 increased by 1.5 fold and 2.5 fold respectively. Although the alcohol content decreased by 2.9%, decrease rate was lower than that observed for the freeze-dried and air blast-dried yeast cultures. Therefore, the results of this study showed that using a liquid starter culture was more advantageous than using the conventional solid culture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.765-769
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• 2002

Improvement of hygienic quality of powdered raw grains and vegetables by fermentation was investigated. Luc-tobacillus sp. isolated from kimchi was used as a starter. The cell counts of coliform group and SS enteric bacteria on the SS agar plate in raw grains and vegetables were 2.3$\times$103 cfu/mL and 8.6$\times$10$^3$ cfu/mL, respectively. The starlet, Lactobacillu sp., reached 10$^{7}$ cfu/mL after 48 hr in fermentation. At that time, the coliform group and enteric bacteria on the SS agar plate were gradually inactivated and eliminated after 60 hr of fermentation. During the fermentation process, pH of the suspension was lowered and acidity increased. Antimicrobial activity of the acidic supernatant of fermented raw grains and vegetal]les against the E. coli sp. and Salmonella sp. was higher than that of lactic acid solution or neutralized supernatant. Therefore, it was considered that antimicrobial effect of the fermented raw grains and vegetal]les might be accelerated by tile synergic effect of acid and bacteriocin, and liquid fermentation of powdered raw grains and vegetables will be effective for inactivation of hygienic microorganisms.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.46-52
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• 1992

The optimum condition for the developement of a whey beverage from the concentrated whey was studied. Reverse osmosis system was used to obtain concentrated lactose from cheese whey. The hydrolysis degree of lactose by $\beta$-D-galactosidase was determined using HPLC (high performance liquid chromatography). The order of hydrolysis degree was 1:1, 2:l and 3:l concentrated lactose. It resulted from the concentrated salt which slightly inhibited $\beta$-D-galactosidase with constant enzyme dosage. The optimum condition for enzyme dosage was 2% in non-concentrated lactose, 3% in 2:l and 3% in 3:l concentrated lactose after 4 hours of reaction. When the 3:l concentrated lactose was used, more than 70% was hydrolyzed by 3% enzyme dosage. Furthermore the change of fermented whey by lactic acid bacteria was investigated. Based on the result of sensory test, the most favorable response was obtained at pH 4.2 and titratable acidity of 0.7% about 6 hours of fermentation at $37^{\circ}C$ with 2%: thermophilic starter.

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.14-20
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• 2004

Bacillus strains capable of producing fibrinolytic enzyme were isolated from traditional fermented Korean soybean paste and Japanese fermented soybean (Natto). Among the 16 strains, a selected Bacillus sp. was identified as bacillus firmus, with 80.7％ homology, by API kit analysis. Seed starter or B. firmus NA-1 was prepared with 5％ soymilk prepared from micronized soybean powder. To produce fibrinolytic enzyme by B. firmus NA-1 the liquid culture was performed with NB broth (pH 7.0) fortified with 1％ galactose, 0.1% tryptone, and 0.5% $K_2$HPO$_4$, by shaking with 180 rpm at 37$^{\circ}C$. Fibrinolytic enzyme activity reached the highest value at 7.8 unit/mL (plasmin unit) after fermentation for 72 hr. The crude fibrinolytic enzyme showed higher relative activity in the range of pH 7.0∼9.0. The activity of crude fibrinolytic enzyme was well maintained even after concentration by the vacuum evaporation at 5$0^{\circ}C$ for 1 hr.

• The Korean Journal of Food & Health Convergence
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• v.9 no.6
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• pp.9-19
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• 2023

Lactobacillus plantarum and Leuconostoc mesenteroides are crucial functional starters and predominant isolates in a wide range of fermented foods, particularly kimchi, whose constituents exhibit bioactive properties. We previously developed a methodology using anion exchange resins to purify peptidyl compounds from Lb. plantarum LBP-K10. Antibacterial cultures of Lb. plantarum LBP-K10 were obtained from the respective cultures' supernatants and filtrates. However, conclusive evidence of the efficacy of kimchi filtrates in eradicating pathogenic bacteria is lacking. We aimed to simulate the potential effects of antibacterial filtrates that contained antibacterial compounds which were derived from cultures of Lb. plantarum LBP-K10. We acquired the kimchi filtrates using a combination of centrifugation and filtration methodologies, without the requirement for inoculation. The filtered liquid from Chinese cabbage kimchi, inoculated with Lb. plantarum LBP-K10 as a starter culture, and the non-inoculated liquid from Chinese cabbage kimchi (referred to as CCK and CCKRef, respectively) were were examined. CCK demonstrated greater inhibitory activity and a more significant bactericidal effect against the bacterial indicator strains. The minimum inhibitory concentration demonstrated comparable outcomes in tests against both Gram-positive and Gram-negative bacteria. This research offers a groundbreaking examination that displays the effectiveness of profiling peptidyl compounds within kimchi filtrates for curing bacterial infections.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.71-77
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• 1997

Sulfonamides, a therapeutically important group of antimicrobial drugs, are widely used to treat and prevent the acute systemic and skin infections in dairy cattle. They also pose an economic hazard through inhibition of growth of dairy starter cultures. This study was carried out to compare four screening methods for detection of sulfamethazine in milk and determine the positive milk sample by HPLC method. Sulfamethazine was used to spike at five levels of sulfamethazine. The Lac-Tek test and CharmII test were also consistent better than TTCII test and Delvo SP test in sulfamethazine detection. Analysis probabilities of obtaining a positive response with TTCII test and Delvo SP test assay at 50 ppb sulfamethazine level in milk samples were only 14%, 42% each. Whereas using the Lac-Tek test and CharmII test would have resulted in 100% identification of the five levels. Determination of sufamethazine using the HPLC method in the spiked milk were 10.64, 19.30, 30.76,38.83 and 50.23 ppb, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.665-670
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• 2011

The rotifer Brachionus plicatilis is one of the most important food organisms in aquaculture. The resting eggs produced by mictic female rotifers are easily stored and hatched, making them useful as the starter for the mass culture of rotifers in marine larval culture. This study examined the optimum preservation method for resting eggs to ensure a high hatching rate. To produce resting eggs, the marine rotifer B. plicatilis was cultured with Nannochloris oculata (KMMCC 16). The resting eggs were harvested and cryopreserved using 5% and 10% methanol (MeOH), dimethylsulfoxide (DMSO), and glycerol as cryoprotectant agents (CPAs). The cryopreservation comprised slow or rapid freezing and the resting eggs were stored for one month in liquid nitrogen ($-196^{\circ}C$). The resting eggs were also dried at different temperatures (30, 40, and $50^{\circ}C$) and for different times (1, 2, and 3 h). In general, the hatching rates of the resting eggs preserved with CPA were higher than those without CPA and the slow freezing method was better than the rapid freezing method. However, the optimum CPA concentration for the hatching rate of the resting eggs varied with the freezing method and kind of CPA, and the CPA also affected the viability of the resting eggs. Dried resting eggs had a high, rapid hatching rate over 80%. The moisture content of the resting eggs cryopreserved in liquid nitrogen affected the hatching rate. Drying at $30^{\circ}C$ for 1 hour resulted in a high hatching rate of the resting eggs. In conclusion, drying at $30^{\circ}C$ for 1 hour and preservation in liquid nitrogen with the slow freezing method, without CPA, is recommended for a high hatching rate (ca. 95%) of rotifer resting eggs.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.5
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• pp.60-71
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• 2007

The startup characteristic of liquid propellant rocket engine should be focused on the stable ignition of combustion chamber and gas generator. Also, to lessen the propellants consumption during this period which doesn't contribute to the flight thrust, the engine has to be transferred to the nominal mode quickly. Because of the risk of test, it is impossible to develop all the startup cyclogram or the specifications of engine by test, so the precedent numerical approach is quite necessary. In this study we developed a mathematical model for the startup phenomena in a liquid rocket engine driven by gas generator-turbopump system based on the commercial 1-D flow system analysis program, Flowmaster. Using this program we proposed a methodology to obtain the specifications of turbine starter and the opening time of shutoff valves for the stable startup of the engine. To verify this methodology we qualitatively compared the analysis results to the typical startup curve of the published engine, then found it is quite well matched.

• Microbiology and Biotechnology Letters
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• v.45 no.4
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• pp.299-304
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• 2017

Biogenic amines such as histamine, tyramine, cadaverine, and putrescine may have detrimental effects on consumers' health; therefore, they must be considered hazardous substances in foods. In recent years, the application of microorganisms that can degrade biogenic amines has become an emerging method for reducing the amount of these amines in foods. Primarily, Bacillus sp. BCNU 9171 was isolated from Doenjang, a Korean traditional fermented soybean paste. The inhibitory effects of the cell-free supernatant (CFS) of Bacillus sp. BCNU 9171 on biogenic amine production by 4 amine-positive food pathogenic bacteria were investigated using high performance liquid chromatography (HPLC). Our results showed that 4 different CFS concentrations-10% [1 ml CFS + 9 ml histidine decarboxylase broth (HDB)], 25% (2.5 ml CFS + 7.5 ml HDB), 50% (5 ml CFS + 5 ml HDB), and 75% (7.5 ml CFS + 2.5 ml HDB)-reduced the biogenic amine production up to 87% compared with that of the control without CFS. These results suggested that it is advisable to use Bacillus sp. strain BCNU 9171 as a starter organism for the manufacture of fermented foods and to ensure food safety since it prevents the accumulation of high amounts of biogenic amines in fermented foods by amine-positive bacteria.