• Journal of Food Hygiene and Safety
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• v.30 no.3
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• pp.295-301
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• 2015

The functions of probiotics, particularly Lactic acid bacteria, have been studied in a range of human diseases, including cancer, infectious diseases, gastrointestinal disorders, and allergies. Among the many benefits associated with the consumption of probiotics, modulation of immune activity has received the most attention. This study aimed at investigating the improved immune stimulatory and stability of L. plantarum when cultivated on modified basal media supplemented with the Undaria pinnatifida co-cultured with L. plantarum. An in vitro test showed that U. pinnatifida media cultured L. plantarum is strong enough to survive in the gastric juice (gastric and bile acid). Mouse macrophage-derived cell lines RAW 264.7 was used to measured immune stimulating activity of L. plantarum. When U. pinnatifida media cultured by L. plantarum was NO and $TNF-{\alpha}$ production is significantly increased compared to basal media cultured L. plantarum. These results show that U. pinnatifida could be applied for a component for cultivation of L. plantarum. This optimized U. pinnatifida medium can be used the improving of stability and immune function on production of probiotics.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.374-381
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• 2004

This study was performed to characterize the mechanism of the acceleration of lactic acid fermentation in milk incubated with potato flour irradiated by ${\gamma}$-ray and two types of lactobacillus, Lactobacillus bulgaricus and Streptococcus thermophillus, and to examine its effect on the quality of yogurt by assessing the acidity of lactic acid, viscosity, free amino acid, and sensory. In lactic acid fermented in the presence of 0.5% (w/w) potato flour, its acidity was higher, its pH was lower, and its viscosity was increased than lactic acid fermented in the absence of potato flour. In the sample fermented with the mixture of S. thermophillus and L. bulgaricus, the acid production rate was highest. In the samples fermented with a single type of bacteria, the acid production rate of S. thermophillus was higher than that the L. bulgaricus. Fermented a single type of bacteria with potato flour, the lysine utilization rate of L. bulgaricus and S. thermophillus was high. L. bulgaricus produced a large quantity of glutamic acid whereas S. thermophillus consumed glutamic acid. In sensory evaluation of yogurt fermented with potato flour, the preference of texture was improved while its color, taste, flavor, and overall preference were decreased. The data suggest that L. bulgaricus stimulates the growth of S. thermophillus by providing free glutamic acid that is required by S. thermophillus and thus the addition of potato flour shortens the fermentation period of yogurt.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.340-348
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• 2009

A total of fifty Hanwoo steers raised from 14 to 29 months were used to investigated the effects of dietary mugwort on the performance and meat quality during refrigerated storage. A feeding trial was tested for 14.7 months and experimental diets included 0 and 2% dried wild mugwort. Total weight gain and average daily gain in this study were significantly higher in mugwort treatment than control treatment. Feed efficiency was improved by mugwort treatment compared with control treatment. Any difference in GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyrubic transaminase), and BUN (blood urea nitrogen) was not observed between groups. Carcass weight and longissimus muscle area were higher for mugwort treatment than control. As fattening increased, total cholesterol in blood increased. Total cholesterol in blood tended to be lower in mugwort treatment than control treatment (p<0.05). The heating loss, $L^*$, $a^*$, $b^*$, chroma, and hue unit of all treatments were not affected treatment, but showed a significant decrease in all treatments during refrigerated storage. For fatty acid composition in longissimus muscle, dietary mugwort supplementation increased unsaturated fatty acid than saturated fatty acid (p<0.05). Based on these findings, it is obvious that supplementation of mugwort at 2% level will be useful to decrease cholesterol, increase unsaturated fatty acid, and improve growth performance of Hanwoo steers.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.736-742
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• 2009

This study was conducted to investigate the effect of various high pressure freezing and thawing treatments on the physical properties of pork. To compare the effects of the freezing and thawing process on meat quality, atmospheric freezing followed by running water thawing (AFRT), pressure shift freezing followed by running water thawing (SFRT), and pressure shift freezing and pressure assisted thawing (SFAT) were conducted at pressure of 250 MPa and cooling temperature of $-22^{\circ}C$. SAFT and SFRT showed a shorter phase transition time and total thawing time than AFRT. The pH value of treated samples increased significantly (p<0.05) compared to unfrozen meat. In addition, SFAT and SFRT showed a higher pHvalue than AFRT. Although the water holding capacity was significantly decreased (p<0.05) for SFAT and SFRT, SFRT reduced drip loss. In regards to color, SFAT and SFRT resulted in a significant increase in color parameters (p<0.05) relative to AFRT, while SFAT produced a higher L*-value. High pressure treatment significantly increased shear force (p<0.05) compared to AFRT, and, where SFRT showed the highest shear force. Therefore, these combined results indicated that the hydrostatic pressure treatment improved the functional properties of pork and increased the freezing and thawing rate.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.431-438
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• 2000

Properties of acid tolerance of an adipic acid-resistant mutant, Leuconostoc paramesenteroides (ANaP100) were studied and compared with those of its paired wild type of Leu. paramesenteroides (LPw). The value of protons permeability of LPw after an acid shock at pH 5.0 was 4.3 min, while the value of ANaP100 was 4.8 min at the same pH. The maximal specific activities of ATPase of LPw and ANaP100 were 0.59 unit/mg protein and 0.63 unit/mg protein at pH 6.0, respectively. The release of magnesium ion from the mutant strain was about 27.3% at pH 4 after 2 hrs, while the wild strain was about 52.2% under the same conditions. The contents of $C_{19:0,cyclo}$ and $C_{18:1}$ in a membrane fatty acid of ANaP100 and LPw were higher and lower, respectively, than that of LPw. These results indicated that acid tolerance of ANaP100 was improved in comparison with that of its wild type, LPw.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.45-50
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• 1994

Conventional Doenjang, three kinds of Improved Doenjang(A; koji: soybean: salt=53: 100: 33, B; koji: soybean: salt=100: 100: 40, C; koji: soybean: salt= 200: 100: 40) prepared with different ratio of koji and salt were made to study the changes in the general contents, characteristics bitter peptides, correlations between bitterness and overall eating quality. 1. Total nitrogen contents increased a little, and amino nitrogen contents in all samples increase markedly. Especially, Amino nitrogen contents of conventrional Doenjang increased more than others. Reducing sugars of doenjang prepared with Asp. oryzae were higher than conventional Doenjang and increased throughout the aging period and Doenjang prepared with Asp. oryzae were more acidic. 2. To characterize bitter peptides in fermented Doenjang, peptides were extracted with 2: 1(v/v) chloroform-methanol and separated by Gel chromato-graphy with Sephadex and TLC. After Gel chromatography and TLC, each fraction examined presence of bitterness and evaluated intensity of bitterness. Amino acid composition of the fractions showing bitter tastes were as follows. Conv. peak 1-1 Trp-(Asp, Arg, Thr, Ser, Glu, Pro)-Phe Imp. A peak 1 Trp-(Glu, Val, Arg, lie)-Phe Imp. B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp. Imp. C peak 1-2 Trp-(Try, Thr, Glu, Pro, Gly)-Phe 3. Sensory evaluation revealed that correlation coefficient between bitterness and overall eating guality was not high.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.165-174
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• 1993

This work was conducted to study the use of L. acidophilus, which exists in humun intestine for the fermentation of Chinese cabbage kimchi. The changes in vitamins, the number of microflora and sensory quality were observed during fermentation after the microflora which was not related to kimchi fermentation was eliminated by treatment with ozone water or ozone gas. The growth rate of L. acidophilus in the cabbage juice was higher than that in MRS broth. The growth of L. acidophilus was slightly promoted by adding 1~2% hot pepper powder while that was inhibited by ginger and garlic. Therefore, it was shown that the regulation of fermentation was possible by addition of spices. The result of treating spice with ozone gas and ozone water 6mg/L/sec for 1 hour was that the survival ratio of total microflora was 6~20%. When L. acidophilus was added to materials after ozone treatment, the fermentation rate was improved and the polysaccharides in the cell wall were used when the usable free sugar was all consumed. The contents of vitamin B$_1$ and C in the ozone treated kimchi was higher than in the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.858-864
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• 2001

This study was performed to investigate the effect of sodium lactate (SL, 60%) and a mixed fat replacer (FR) on the product quality and shelf-life effect of low-fat bologna sausage (LFBS) in a model system during refrigerated storage. Low-fat and regular-fat bologna sausages had pH values ranged from 6.15 to 6.30 and water activity values ranged from 0.95 to 0.96. LFBS had a moisture content of 74~76%, <2% fat and 14~15% protein, whereas regular-fat bologna had 60% moisture, 22% fat and approximately 12% protein in the final products. Expressible moisture (%) increased (p<0.05) in all bolognas, resulting in the soft texture, as the storage time (weeks) increased. LFBS manufactured with SL and a FR had lower (p<0.05) the cooking loss (%) and had higher (p<0.05) texture profile analysis (TPA) values than the regular-fat counterpart. As the sodium lactate level increased up to 5% in the formulation of LFBS, vacuum purge and TPA hardness values also increased (p<0.05), but thiobarbituric acid (TBA) values decreased (p<0.05). Total plate counts of LFBS were reduced (p<0.05) when the addition level of 60% SL solution was more than 3.3%. This result indicated that the increased level of SL (>3.3%) in the combination of a FR in the formulation of LFBS improved the product quality and did inhibit the total microbial growth of LFBS during storage, as compared to the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.447-454
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• 1991

Chopped garlic was added to beef to determine its effect on the protein digestion during storage and heat treatment. The digestibility of raw beef without garlic was not significantly changed during storage at $4^{\circ}C$, but increased as garlic added and aging time increased. The optimal aging time and amount of garlic added was varied with heating time. Trypsin inhibitor did not change the digestibility of beef due to its thermal inactivation. Gel chromatography revealed that the lower molecular weight peptides(2,200~6,150 dalton) were shown in beef-garlic mixture through aging and heating procedure. When aged beef with garlic was digested with four-enzyme system, the soluble portion was increased significantly in comparison with that from raw beef without garlic. Protein quality of beef, as measured by computed PER(C-PER), was improved from 2.14 of raw beef to 2.50 of aged beef with chopped garlic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.372-379
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• 2016

This study was performed to investigate the quality characteristics of various salted (8, 10, and 12%) Doenjang prepared with fermented Hwangchil (Dendropanax morbifera) extract as well as the effect of Bacillus methylotrophicus S8 strain, isolated from soy sauce, as a starter culture. After fermentation, the total cell number of low-salted Doenjang (8% and 10%) prepared with fermented Hwangchil was lower than that of Doenjang without fermented Hwangchil. Low-salted Doenjang (8% and 10%) showed higher total acidity, amino acid, and organic acid levels as well lower pH levels than high-salted Doenjang (12%), indicating active fermentation. The highest levels of lactic acid (48.1 mg/L) and glutamic acid (549.0 mg/L) were observed in low-salted Doenjang (8%) fermented with B. methylotrophicus S8 strain. The low-salted Doenjang (8%) fermented with B. methylotrophicus S8 also showed the highest score in overall preference of sensory evaluation. These results indicate that Hwangchil extract fermented with B. methylotrophicus S8 can be used as a starter for making low-salted Doenjang, resulting in improved palatability, and inhibition of abnormal fermentation.