• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.727-732
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• 2010

The pH, acidity, color, amino acid, reducing sugar, total sugar, and alcohol contents of puffed millet powder supplemented with different concentrations of millet takju were investigated during 10 days of fermentation. The pH ranged from 4.06 to 4.58 at day 1 but decreased drastically to 3.55-3.64 at day 2. With the exception of day 1, a higher pH was observed with a higher concentration of puffed millet powder (p<0.05). Acidity tended to increase quickly over time, especially for the 0% sample after day 4 (p<0.05). The sudden increase of acidity at day 2 agreed with the pH decrease. A lower concentration of puffed millet powder resulted in a greater Hunter "L" value (p<0.05) and tended to show lower Hunter "a" and higher Hunter "b" values on the same day. Amino acids increased over time, and a higher concentration of puffed millet powder resulted in lower amino acid content on the same day after day 3 (p<0.05). After a rapid reduction in reducing sugar on day 2 (p<0.05), minimal differences were observed in the samples after day 4. The 75% puffed millet powder sample showed the highest reducing sugar content, except on days 8 and 9 (p<0.05). Total sugars decreased rapidly by day 3, and then either remained unchanged or decreased after day 4. Higher alcohol concentrations were observed with higher concentrations of puffed millet powder, except on day 1 (p<0.05).

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.797-800
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• 2015

The effect of raw wheat flour on starch retrogradation retardation was investigated in a rice starch paste model. Specifically, in terms of amylase activity present in the wheat flour, the retardation effect was investigated depending on reaction temperature (40, 60, and $80^{\circ}C$), incubation time (0, 20, 40, and 60 min), and wheat flour addition levels (0-10%). An increase in wheat flour concentration resulted in a rapid decrease in the elastic modulus (G') as the incubation time increased. The G' changes of the rice starch pastes were furthermore fitted by the first order reaction for the reaction rate estimation on the temperature basis. The experimental reaction rate of the paste sample incubated with 10% wheat flour at $40^{\circ}C$ exhibited good agreement with the predicted value. This result implied that the first order reaction kinetics could be suitable to predict the changes in the G' as a function of incubation temperature and wheat flour concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.634-640
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• 1994

This study was investigate to see the effects of preparation methods on the physicochemical and sensory characteristics of cucumber preserved with salt. The preparation methods were brining the cucumbers in 10 % NaCl solution (boiled, method A), 205 NaCl solution (boiled, method B) an d20 % NaCl solution (cool to $25^{\circ}C$ after boiling, method C). The cucumber preserved with boiled solution and high salt concentration showed slow fermentation rate. The rate of salt penetration during brining of cucumber preserved with salt increased. The green value of cucumber preserved with salt by method B was lower than by method A and C. The cutting force of cucumber preserved with walt measured by texture analyzer showed a rapid increasing rate during initial brining periods. As a result of the sensory evaluation for cucumber preserved with salt, there were significant differences in most of characteristics between the samples at 5% level. The cucumber preserved with salt in boiled 10% NaCl solution (method A) showed the highest scores in most of the characteristics.

• Journal of Veterinary Clinics
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• v.6 no.2
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• pp.307-318
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• 1989

In recent years much attention has been paid to swine respiratory infection caused by Pasteurella(P) multocida with rapid expansion of pork Industry in Korea. The present study was performed to observe the etiologic situation of P. multocida infection by bacteriological, serological(serotyping) and pathological examinations with the lungs respectively. In addition antibiotic susceptibility test was carried out against the isolated strains of P. multocida. The results obtained are as follows : 1. Eighteen strains(12.8％) wert isolated from the 140 cases of swine lungs examined, and biological and biochemical characteristics of the isolates were the sam as those in the references of other workers, whereas some differences were observed in sugar fermentation and enzyme activity according to the strain of isolates. 2. Capsular serotyping performed on 18 P. multocida revealed that 13 strains(72.2％) were A type and 5 strains(27.8％) were D type, respectively. 3. When serotyping was performed against somatic antigen on 18 strains capsular types of which were identified as described above 9(50％), 3(16.7％) and 4(22.2％) strains belong to 1:A, 3:A and 2:D, respectively, but untypable 2 strains(11.1％) were observed. 4. Antibiotic susceptibility test by employing disc method for 24 kinds of drugs revealed that 15 kinds of antibiotics were sensitive to 18 strains of P. multocida isolated such as ampicillin(l00％), penicillin(100％), cloxacillin(56％), piperacillin(70％), cefotaxime(30%), minocycline(60％), chloramphenicol(95％), erythromycin(39％), kanamycin(17％), gentamicin(70%), amikasin(30%), colistin(78％) and nalidixic acid(5％), respectively, but resistant to 9 kinds of antibiotics such as sulpenicillin, cefazolin, cephalothin, cefametazol, cefoperazone, kitasamycin, oleandomycin. lincomycin and bacitracin. 5. Pathological features of 60 cases of swine lungs indicated that pneumonic .lesions were observed in 38 cases(63.3％) examined by macroscopic finding, in which lesions of 8 cases(13.4％) would correspond to those of mycoplasmal infection, and 30 cases(50％) were similar to viral infection by histopathological finding, whereas 22 cases(36.7％) were considered to be normal by ecropsy or histopathological finding.

• KSBB Journal
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• v.23 no.5
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• pp.425-430
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• 2008

Hydrogen sulfide ($H_2S$) is a by-product of metabolism of amino acids including sulfur and alcoholic fermentation, it is generally thought of in terms of a poisonous gas. Though $H_2S$ can have a negative impact on the perceived quality of fermented drinks due to an undesirable aroma, it plays prominent roles as a neuromodulator in the mammalian brain as well as a smooth muscle relaxant. Nowadays studies on the proteins which produce $H_2S$ are carried out in various fields such as structure, function, and metabolism. Here we propose to develop a simple and rapid $H_2S$ forming assay method, which will lead to speed up preparing the $H_2S$ forming proteins for identification by MALDI-TOF MS analysis. We detected three kinds of proteins which produce $H_2S$ in the crude extract of Saccharomyces cerevisiae. Those proteins were cystathionie $\beta$-synthase, O-acetylserine sulfhydrylase, and cystathionine $\gamma$-lyase.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.263-272
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• 1987

Lactobacillus bulgaricus (KFCC 35463) and Kluyveromyres fragilis (KFCC 35458) were inoculated together in soymilk, and then growth characteristics, acid production and the conditions suitable for acid production were investigated. L. bulgaricus produced more acid and the rate of acid production was more rapid when this organism was incubated with K. fragilis in soymilk than when it was incubated singly. Studying the conditions suitable for acid production in soymilk, optimum acid production by the mixed cultures of L. bulgaricus and K. fragilis was achieved with a temperature of $35{\sim}37^{\circ}C$, a 1:2 (O.D.660) ratio of L. bulgaricus to K. fragilis at inoculum, a 1.0% level of sucrose fortification or a 1.5% level of skim milk powder fortification and a culture time of 24hr. Under these conditions the amount of acid produced by the single culture of L. bulgaricus and the mixed cultures of L. bulgaricus and K. fragilis were 0.14% and 0.41%, respectively, in soymilk, 0.13% and 0.70%, respectively, in soymilk fortified with 1.0% level of sucrose. These indicate that the amount of acid produced by mixed cultures is about 2.9-fold greater in soymilk and about 5.4-fold greater in soymilk fortified with 1.0% level of sucrose than that produced by the single culture of L. bulgaricus. The amount of acid produced in soymilk fortified with 1.5% level of skim milk powder was 0.84% level for both of the single culture of L. bulgaricus and the mixed cultures of L. bulgaricus and K. fragilis after 24hr incubation. However, the amount of acid produced by the mixed culture with K. fragilis was greater than that produced by the single culture of L. bulgaricus onlv in soymilk fortified with lower levels of skim milk powder than 1.5%.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1273-1273
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• 2001

The efficiency of the luminal fermentation process influences overall efficiency of luminal production, animal health and reproduction. Ruminant production systems have a significant impact on the global environment, as well. Animal wastes contribute to pollution of the environment as ammonia volatilized to the air and nitrate leached to ground water. Microbial protein synthesis in the rumen satisfies a large proportion of the protein requirements of animals. Quantifying the microbial synthesis is possible by using markers for lumen bacteria and protozoa such as nucleic acids, purine bases, some specific amino acids, or by isotopic $^{15}N,^{32}P,\;and\;^{35}S$ labelled feeds. All those methods require cannulated animals, they are time-consuming and some methods are very expensive as well. Many attempts have been made to find an alternative method for indirect measurement of microbial synthesis in intact animals. The present investigations aimed to assess possibilities of NIRS for prediction of purine nitrogen excretion and ruminal microbial nitrogen synthesis by NIR spectra of urine. Urine samples were collected from 12 growing sheep,6 of them male, and 6- female. The sheep were included in feeding experiment. The ration consisted of sorghum silage and protein supplements -70:30 on dry matter basis. The protein supplements were chosen to differ in protein degradability. The urine samples were collected daily in a vessel containing $60m{\ell}$ 10% sulphuric acid to reduce pH below 3 and diluted with tap water to 4 liters. Samples were stored in plastic bottles and frozen at $-20^{\circ}C$ until chemical and NIRS analysis. The urine samples were analyzed for purine derivates - allantoin, uric acid, xantine and hypoxantine content. Microbial nitrogen synthesis in the lumen was calculated according to Chen and Gomes, 1995. Transmittance urine spectra with sample thickness 1mm were obtained by NIR System 6500 spectrophotometer in the spectral range 1100-2500nm. The calibration was performed using ISI software and PLS regression, respectively. The following statistical results of NIRS calibration for prediction of purine derivatives and microbial protein synthesis were obtained.(Table Omitted). The result of estimation of purine nitrogen excretion and microbial protein synthesis by NIR spectra of urine showed accuracy, adequate for rapid evaluation of microbial protein synthesis for a large number of animals and different diets. The results indicate that the advantages of the NIRS technology can be extended into animal physiological studies. The fast and low cost NIRS analyses could be used with no significant loss of accuracy when microbial protein synthesis in the lumen and the microbial protein flow in the duodenum are to be assessed by NIRS.

• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.227-232
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• 1982

The methods determining the growth rate of mold on beans were investigated in order to compare the growth of Aspergillus oryzae on lupinseed to that on soybean. The growth of A. oryzae on cooked whole or paste form of bean substrates was evaluated by the measurements of colony diameter and hyphae length of the mold. The mold showed characteristic lag times to form the colony on different types of substrate. The growth of colony diameter was coincided with the increase in $\alpha$-amino nitrogen content of the substrate when the moisture level of the substrates was similar each other. The colony diameter and the cultivation time after the lag period showed a straight line relationship, from which the growth rate was estimated. in general, lupinseed paste allowed faster growth of A. oryzae than soybean paste at the initial growth phase. The lag time to form the colony was 24.0 hrs on lupinseed paste and 44.4 hrs on soybean paste. The growth rate after colony formation was, however, 7.05 mm/day for lupinseed paste and 8.83mm/day for soybean paste, which indicated that the growth rate after the lag period was faster on soybean compared to lupinseed. The sporulation time of the mold was related to the lag time for the colony formation. The measurement of hyphae length on whole beans could be used as a simple and rapid method of estimating the growth property of mold on different substrates.11 showed that the growth of A. oryzae was partly hindered by the thick hull of the lupinseed.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.278-285
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• 1991

This study was conducted to manufacture a good qualified organic fertilizer with cow dung through rapid composting process, and the proposal guideline of the degree of maturity could be estimated with the measurement of final product. It included total nitrogen content of above 2% on an oven-dry material basis, C/N ratio of below 20, CEC of more than about 60 me/100g, ratio of carbon in reducing sugar to the total carbon of below 35%, and temperature in pile of above $60^{\circ}C$. The total nitrogen content, the C/N ratio, and the Paper Chromatographic method couldn't be the guideline to evalute the maturity of cow dung compost. CEC was increased in increased fermentation and it was high in the high fermented temperature plots which were cow dung+ shredded bark in 1988, cow+dung+wood chips in 1989, and cow dung+rice straws in 1990. The ratio of carbon in reducing sugar to total carbon in 1990 was lower in cow dung+saw dust than cow dung+rice straws that was the highest temperature in pile. Generally cow dung was mixed well with saw dust and thus the total carbon of the product was high. The measurement of the temperature in pile seems to be a indirect guideline of maturity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.363-369
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• 1989

In this study, the biochemical characterization of strong proteolytic bacteria and their extracellular pretense isolated from fermented fish paste were experimented for the purpose of industrial large scale-production by accelerated fermentation. The results obtained were as follows: Among 4 strains isolated from fermented fish paste, B. subtilis p-4 and B. licheniformis p-5, which grow well at $40^{\circ}C$, pH 7.0 and $1\%$ of salt contents, were the best proteolytic bacteria and were shown $0.48hr^{-1}$, $0.49hr^{-1}$ of specific growth rate in TPY medium, respectively. Maximum enzyme activity of B. subtilis p-4 was 335n mole-Tyr/min.ml after 30 hrs and that of B. licheniformis p-5 was 300n mole-Tyr/min.ml after 28 hrs of shaking culture. Purified pretense produced by B. subtilis p-4 and B. licheniformis p-5 showed maximum activity at $50^{\circ}C$, pH 7.0 and molecular weight were estimated to be 18,000, 30,000 by sephadex G-100 gel filtration, respectively. These were supposed to be a kind of metal chelator sensitive neutral pretense from the result of high sensitivity against EDTA, o-phe-nanthroline and metal ions such as $Cu^{2+},\;Ni^{2+},\;Zn{2+}$.