• Title/Summary/Keyword: D-(-)-lactic acid

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Effect of high-dose ginsenoside complex (UG0712) supplementation on physical performance of healthy adults during a 12-week supervised exercise program: A randomized placebo-controlled clinical trial

  • Lee, Eon Sook;Yang, Yun Jun;Lee, Jun Hyung;Yoon, Yeong Sook
    • Journal of Ginseng Research
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    • v.42 no.2
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    • pp.192-198
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    • 2018
  • Background: Ginseng has been used as an ergogenic agent, although evidence for its effectiveness is weak. A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the effect of a ginsenoside complex (UG0712) on changes in exercise performance. Methods: Sedentary individuals (n = 117) were randomly assigned into one of three groups: low-dose ginsenoside supplementation (100 mg/d, n = 39), high-dose ginsenoside supplementation (500 mg/d, n = 39), or a placebo group (500 mg/d, n = 39). All participants underwent a supervised 12-wk aerobic and resistance exercise training course. To assess the effects of supplementation on physical performance, maximal oxygen consumption ($VO_2max$), anaerobic threshold (AT), lactic acid, and muscle strength of the dominant knee were measured at baseline, every visit, and after the training program. Results: Both ginsenoside groups showed significant increases in $VO_2max$ and muscular strength during exercise training. There were no definite changes in AT and lactic acid levels over time. After exercise training, there were definite differences in the $VO_2max$ (28.64.9 to $33.7{\pm}4.9ml/kg/min$ in high-dose group vs. $30.4{\pm}6.7$ to $32.8{\pm}6.6ml/kg/min$ in placebo, p = 0.029) and AT ($19.3{\pm}4.2$ to $20.9{\pm}3.5ml/kg/min$ in high-dose group vs. $20.0{\pm}5.1$ to $20.0{\pm}4.9ml/kg/min$ in placebo, p = 0.038) between the high-dose ginsenoside and placebo groups. However, there was no difference in $VO_2max$ between the low-dose ginsenoside and placebo groups (p = 0.254). There were no differences in muscular strength during exercise training among the three groups. Conclusion: High-dose ginsenoside supplementation (UG0712) augmented the improvement of aerobic capacity by exercise training.

Changes in Lactic Acid Bacteria and Physicochemical Properties of Yogurt Made with High Pressure Processing Treated Milk (고압처리 원유로 제조한 발효유의 저장 중 유산균 수 변화와 이화학적 특성)

  • Ahn, Sung-Il;Chung, In-Ae;Chung, Woon-Si;Jhoo, Jin-Woo;Kim, Gur-Yoo;Jeon, Jung-Tae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.6
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    • pp.889-893
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    • 2016
  • This study was carried out to investigate the physicochemical and fermentation properties of yogurt made from high pressure processing (HPP) treated milk. Raw milk and commercial yogurt starter were used to make yogurt. Raw milk was HPP treated at 350 or 450 MPa (HPP 350 or 450) for 15 min or heat treated at $80^{\circ}C$ for 10 min. The numbers of lactic acid bacteria of the HPP treated group (HPP yogurt) rapidly increased during 2~4 h, whereas there was not significant difference from control (P<0.05). Titratable acidity of all samples increased, and pH decreased during storage from 0.99 to 1.24%, as well as from 4.59 to 4.20, respectively. It is confirmed that these values are in general ranges for yogurt. Control showed higher viscosity than HPP 350. Syneresis was significantly lower than that of the control (P<0.05). Based on the data obtained from the present study, HPP treatment was effective to enhance the quality of yogurt.

Comparison of the Palatability Related with Characteristics of Beef Carcass Grade B2 and D (상등급과 등외등급 쇠고기의 기호특성 비교)

  • 문윤희;강세주;현재석;강희곤;정인철
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.6
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    • pp.1152-1157
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    • 2001
  • Two kinds of samples were prepared from the loin in the carcass with grade B2 and D, which were chilled for 24 hour after slaughter. The fresh beef in this study were obtained by chilling the loin for 1 day after wrapping them. On the other hand, the chilled beef were obtained by cutting the loin by 500 g and chilling them for 30 day after vacuum packing. The experiment was carried out to compare the palatability related with characteristics of loin with grade B2 and D and to investigate the chilling effect of the loin with grade D. In the case of fresh beef, it was found that the loin with grade B2 has better meat color, but lower pH, lactic acid content, and myoglobin content, than them of the loin with grade D. Also, the loin with grade B2 has lower tenderness due to its low hardness and chewiness, and high myofibrillar fragmentation index (MFI). Furthermore, it has high monounsaturated fatty acid/saturated fatty acid (MUFA/SFA) and ATP content, and good raw meat aroma. It also shows an excellent palatability of cooked meat, although it has low cooking loss and heat shotening. On the other hand, the loin with grade D has higher chilling effect on hardness, chewiness, MFI and MUFA/SFA, than them of the loin with grade B2. However, in the case of chilled beef, the loin with grade D shows much worse tenderness, cooked meat aroma, and palatability than them of the loin with grade B2.

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Microbiological and Enzymological Studies on Takju Brewing (탁주(濁酒) 양조(釀造)에 관(關)한 미생물학적(微生物學的) 및 효소학적(酵素學的) 연구(硏究))

  • Kim, Chan-Jo
    • Applied Biological Chemistry
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    • v.10
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    • pp.69-100
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    • 1968
  • 1. In order to investigate on the microflora and enzyme activity of mold wheat 'Nuruk' , the major source of microorganisms for the brewing of Takju (a Korean Sake), two samples of Nuruk, one prepared at the College of Agriculture, Chung Nam University (S) and the other perchased at a market (T), were taken for the study. The molds, aerobic bacteria, lactic acid bacteria, and yeasts were examined and counted. The yeasts were classified by the treatment with TTC (2, 3, 5 triphenyltetrazolium chloride) agar that yields a varied shade of color. The amylase and protease activities of Nuruk were measured. The results were as the followings. a) In the Nuruk S found were: Aspergillus oryzae group, $204{\times}10^5$; Black Aspergilli, $163{\times}10^5$; Rhizogus, $20{\times}10^5$; Penicillia, $134{\times}10^5$; Areobic bacteria, $9{\times}10^6-2{\times}10^7$; Lactic acid bacteria, $3{\times}10^4$ In the Nuruk T found were: Aspergillus oryzae group, $836{\times}10^5$; Black Aspergilli, $286{\times}10^5$; Rhizopus, $623{\times}10^5$; Penicillia, $264{\times}10^5$; Aerobic bacteria, $5{\times}10^6-9{\times}10^6$; Lactic acid bacteria, $3{\times}10^4$ b) Eighty to ninety percent of the aerobic bacteria in Nuruk S appeared to belong to Bacillus subtilis while about 70% of those in Nuruk T seemed to be spherical bacteria. In both Nuruks about 80% of lactic acid bacteria were observed as spherical ones. c) The population of yeasts in 1g. of Nuruk S was about $6{\times}10^5$, 56.5% of which were TTC pink yeasts, 16% of which were TTC red pink yeasts, 8% of which were TTC red yeasts, 19.5% of which were TTC white yeasts. In Nuruk T(1g) the number of yeasts accounted for $14{\times}10^4$ and constituted of 42% TTC pink. 21% TTC red pink 28% TTC red and 9% TTC white. d) The enzyme activity of 1g Nuruk S was: Liquefying type Amylase, $D^{40}/_{30},=256$ W.V. Saccharifying type Amylase, 43.32 A.U. Acid protease, 181 C.F.U. Alkaline protease, 240C.F.U. The enzyme activity of 1g Nuruk T was: Liquefying type Amylase $D^{40}/_{30},=32$ W.V. Saccharifying type amylase $^{30}34.92$ A.U. Acid protease, 138 C.F.U. Alkaline protease 31 C.F.U. 2. During the fermentation of 'Takju' employing the Nuruks S and T the microflora and enzyme activity throughout the brewing were observed in 12 hour intervals. TTC pink and red yeasts considered to be the major yeasts were isolated and cultured. The strains ($1{\times}10^6/ml$) were added to the mashes S and T in which pH was adjusted to 4.2 and the change of microflora was examined during the fermentation. The results were: a) The molds disappeared from each sample plot since 2 to 3 days after mashing while the population of aerobic bacteria was found to be $10{\times}10^7-35{\times}10^7/ml$ inS plots and $8.2{\times}10^7-12{\times}10^7$ in plots. Among them the coccus propagated substantially until some 30 hours elasped in the S and T plots treated with lactic acid but decreased abruptly thereafter. In the plots of SP. SR. TP. and TR the coccus had not appeared from the beginning while the bacillus showed up and down changes in number and diminished by 1/5-1/10 the original at the end stage. b) The lactic acid bacteria observed in the S plot were about $7.4{\times}10^7$ in number per ml of the mash in 24 hours and increased up to around $2{\times}10^8$ until 3-4 days since. After this period the population decreased rapidly and reached about $4{\times}10^5$ at the end, In the plot T the lactic acid becteria found were about $3{\times}10^8$ at the period of 24 fours, about $3{\times}10$ in 3 days and about $2{\times}10^5$ at the end in number. In the plots SP. SR. TP, and TR the lactic acid bacteria observed were as less as $4{\times}10^5$ at the stage of 24 hours and after this period the organisms either remained unchanged in population or ceased to exist. c) The maiority of lactic acid bacteria found in each mash were spherical and the change in number displayed a tendency in accordance with the amount of lactic acid and alcohol produced in the mash. d) The yeasts had showed a marked propagation since the period of 24 hours when the number was about $2{\times}10^8$ ㎖ mash in the plot S. $4{\times}10^8$ in 48 hours and $5-7{\times}10^8$ in the end period were observed. In the plot T the number was $4{\times}10^8$ in 24 hours and thereafter changed up and down maintaining $2-5{\times}10^8$ in the range. e) Over 90% of the yeasts found in the mashes of S and T plots were TTC pink type while both TTC red pink and TTC red types held range of $2{\times}10-3{\times}10^7$ throughout the entire fermentation. f) The population of TTC pink yeasts in the plot SP was as $5{\times}10^8$ much as that is, twice of that of S plot at the period of 24 hours. The predominance in number continued until the middle and later stages but the order of number became about the same at the end. g) Total number of the yeasts observed in the plot SR showed little difference from that of the plot SP. The TTC red yeasts added appeared considerably in the early stage but days after the change in number was about the same as that of the plot S. In the plot TR the population of TTC red yeasts was predominant over the T plot in the early stage which there was no difference between two plots there after. For this reason even in the plot w hers TTC red yeasts were added TTC pink yeasts were predominant. TTC red yeasts observed in the present experiment showed continuing growth until the later stage but the rate was low. h) In the plot TP TTC pink yeasts were found to be about $5{\times}10^8$ in number at the period of 2 days and inclined to decrease thereafter. Compared with the plot T the number of TTC pink yeasts in the plot TP was predominant until the middle stage but became at the later stage. i) The productivity of alcohol in the mash was measured. The plot where TTC pink yeasts were added showed somewhat better yield in the earely stage but at and after the middle stage the difference between the yeast-added and the intact mashes was not recognizable. And the production of alcohol was not proportional to the total number of yeasts present. j) Activity of the liquefying amylase was the highest until 12 hours after mashing, somewhat lowered once after that, and again increased around 36-48 hours after mashing. Then the activity had decreased continuously. Activity of saccharifying amylase also decreased at the period of 24 hours and then increased until 48 hours when it reached the maximum. Since, the activity had gradually decreased until 72 hours and rapidly so did thereafter. k) Activity of alkaline protease during the fermentation of mash showed a tendency to decrease continusously although somewhat irregular. Activity of acid protease increased until hours at the maximum, then decreased rapidly, and again increased, the vigor of acid protease showed better shape than that of alkaline protease throughout. 3. TTC pink yeasts that were predominant in number, two strains of TTC red pink yeasts that appeared throughout the brewing, and TTC red yeasts were identified and the physiological characters examined. The results were as described below. a) TTC pinkyeasts (B-50P) and two strains of TTC red pink yeasts (B-54 RP & B-60 RP) w ere identified as the type of Saccharomyces cerevisiae and TTC pink red yeasts CB-53 R) were as the type of Hansenula subpelliculosa. b) The fermentability of four strains above mentioned were measured as follows. Two strains of TTC red pink yeasts were the highest, TTC pink yeasts were the lowest in the fermantability. The former three strains were active in the early stage of fermentation and found to be suitable for manufacturing 'Takju' TTC red yeasts were found to play an important role in Takju brewing due to its strong ability to produce esters although its fermentability was low. c) The tolerance against nitrous acid of strains of yeast was marked. That against lactic acid was only 3% in Koji extract, and TTC red yeasts showed somewhat stronger resistance. The tolerance against alcohol of TTC pink and red pink yeasts in the Hayduck solution was 7% while that in the malt extract was 13%. However, that of TTC red yeasts was much weaker than others. Liguefying activity of gelatin by those four strains of yeast was not recognized even in 40 days. 4. Fermentability during Takju brewing was shown in the first two days as much as 70-80% of total fermentation and around 90% of fermentation proceeded in 3-4 days. The main fermentation appeared to be completed during :his period. Productivity of alcohol during Takju brewing was found to be apporximately 65% of the total amount of starch put in mashing. 5. The reason that Saccharomyces coreanuss found be Saito in the mash of Takju was not detected in the present experiment is considered due to the facts that Aspergillus oryzae has been inoculated in the mold wheat (Nuruk) since around 1930 and also that Koji has been used in Takju brewing, consequently causing they complete change in microflora in the Takju brewing. This consideration will be supported by the fact that the original flavor and taste have now been remarkably changed.

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Effect of Maturity at Harvest and Wrap Colors on the Quality of Round Baled Rye Silage (수확시 숙기 및 비닐색이 호밀 라운드베일 사일리지 품질에 미치는 영향)

  • Kim, J.G.;Kim, D.A.;Chung, E.S.;Seo, S.;Kim, J.D.;Ham, J.S.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.19 no.4
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    • pp.355-362
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    • 1999
  • This experiment was conducted to evaluated the effect of maturity at harvest and wrap colors on the quality of round baled rye(Secal cereale L.) silage at the forage experimental field, Grassland and Forage Crops Division, National Livestock Research Institute, Suwon in 1998. The experiment was consist of split-plot design with three repications. The main plots were three different harvesting stages : boot, heading, and flowering stages, the subplots were wrap colors : white, black, and light green color. Acid detergent fiber(ADF) and neutral detergent fiber(NDF) of rye silage were increased with delayed harvesting date, but there were no significant differdence among wrap colors. However, average in vitro dry matter digestibility (IVDMD) of rye silage with white color wrap tended to have higher than those of other colors. The silage pH of heading stage was highest (5.12), and that of flowering stage was lowest (4.57) in different harvest stages. Among tested wrap colors, white color wrap resulted on lowest pH than others (p<0.05), but there were no significant difference between black and light green color. Dry matter (DM) content of rye silage were increased as harvest stage progressed (p<0.05). However, DM content of white color was highest among warp colors, but there was signifiant difference (p<0.05). Ammonia-N content of silage harvested at boot stage was the highest in harvest stage, but there was no difference between heading and flowering stages. Among wrap colors tested, ammonia-N content of black color was highest, but there was no significant difference. The number of lactic acid bacteria of white colors was highest in different colors, and that of flowering stage was highest among harvest stage. Acetic and butyric acid contents were decreased as harvest stage progressed, and lactic acid was increased from 6.33 to 7.98%. However, wrap colors did not influence lactic acid concentration. Among different wrap colors, outside temperature of rye silage was affected by air temperature, but effect of inside temperature was minimal. Black color wrap increased inside temperature by $3{\sim}5^{\circ}C$. The results of this study indicate that rye should be harvested for round bale silage after heading stage. The quality of rye silage wrapped white and light green color will increase slightly.

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Mixed organic acids improve nutrients digestibility, volatile fatty acids composition and intestinal microbiota in growing-finishing pigs fed high-fiber diet

  • Li, Miao;Long, Shenfei;Wang, Qianqian;Zhang, Lianhua;Hu, Jiangxu;Yang, Jie;Cheng, Zhibin;Piao, Xiangshu
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.6
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    • pp.856-864
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    • 2019
  • Objective: The objective of this study was to investigate effects of mixed organic acids (MOA) on nutrient digestibility, volatile fatty acids composition and intestinal microbiota in growing-finishing pigs fed high wheat bran diet. Methods: Six crossbred barrows ($Duroc{\times}Landrace{\times}Yorkshire$), with an average body weight $78.8{\pm}4.21kg$, fitted with T-cannulas at the distal ileum, were allotted to a double $3{\times}3$ Latin square design with 3 periods and 3 diets. Each period consisted of a 5-d adjustment period followed by a 2-d total collection of feces and then a 2-d collection of ileal digesta. The dietary treatments included a corn-soybean-wheat bran basal diet (CTR), mixed organic acid 1 diet (MOA1; CTR+3,000 mg/kg OA1), mixed organic acid 2 diet (MOA2; CTR+2,000 mg/kg OA2). Results: Pigs fed MOA (MOA1 or MOA2) showed improved (p<0.05) apparent total tract digestibility (ATTD) of gross energy, dry matter and organic matter, and pigs fed MOA2 had increased (p<0.05) ATTD of neutral detergent fiber compared to CTR. Dietary MOA supplementation decreased (p<0.05) pH value, and improved (p<0.01) concentrations of lactic acid and total volatile fatty acids (TVFA) in ileum compared to CTR. Pigs fed MOA showed higher (p<0.05) concentration of acetic acid, and lower (p<0.05) content of formic acid in feces compared to CTR. Pigs fed MOA1 had increased (p<0.05) concentration of TVFA and butyric acid in feces. Pigs fed MOA1 showed higher concentration of Lactobacillus and lower concentration of Escherichia in feces compared to CTR. Conclusion: Dietary supplementation of MOA 1 or 2 could improve nutrients digestibility, TVFA concentration and intestinal flora in growing-finishing pigs fed high fiber diet.

Identification, Characteristics, and Growth Inhibition of the Strain Isolated from Spoiled Wet Noodle

  • Kim, Hyeong-Hyoi;Jeong, Eun-Jeong;Jeong, Do-Yeong;Kim, Yong-Suk;Shin, Dong-Hwa
    • Food Science and Biotechnology
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    • v.14 no.4
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    • pp.461-465
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    • 2005
  • To determine the cause of wet noodle spoilage, microorganisms isolated from wet noodles were identified and characterized. In addition, the growth inhibitory effects of organic acid mixture (OA: lactic acid 27.8%, acetic acid 12.0%, succinic acid 1.0%) and sodium dehydroacetate (SD) on the isolated strain were estimated in nutrient broth medium. The isolated strain was Gram-positive, rod shaped, motile, and spore forming. Based on physiological characteristics and the API 50 CHB-kit test results for the assimilation of 49 carbohydrates, the isolated strain was identified as Bacillus amyloliquefaciens (92.6%), which is able to degrade starch. Decimal reduction times (D-values) at 100, 105, and $110^{\circ}C$ for spores of B. amyloliquefaciens were 8.5, 5.1, and 2.5 min, respectively, and the z-value was $12.8^{\circ}C$. We estimated that B. amylo-liquefaciens isolated from spoiled wet noodles was a thermophilic species having high heat-resistance. Viable cell numbers in wet noodles and broth medium inoculated with B. amyloliquefaciens were decreased by 2-4 log cycles by combined treatment with 0.03 or 0.05% OA and 0.3% SD. These results revealed that OA combined with SD could be used as a potential agent to inhibit B. amyloliquefaciens in wet noodles.

Effects of Ensiling Fermentation and Aerobic Deterioration on the Bacterial Community in Italian Ryegrass, Guinea Grass, and Whole-crop Maize Silages Stored at High Moisture Content

  • Li, Yanbing;Nishino, Naoki
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.9
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    • pp.1304-1312
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    • 2013
  • The effects of storage period and aerobic deterioration on the bacterial community were examined in Italian ryegrass (IR), guinea grass (GG), and whole-crop maize (WM) silages. Direct-cut forages were stored in a laboratory silo for 3, 7, 14, 28, 56, and 120 d without any additives; live counts, content of fermentation products, and characteristics of the bacterial community were determined. 2,3-Butanediol, acetic acid, and lactic acid were the dominant fermentation products in the IR, GG, and WM silages, respectively. The acetic acid content increased as a result of prolonged ensiling, regardless of the type of silage crop, and the changes were distinctively visible from the beginning of GG ensiling. Pantoea agglomerans, Rahnella aquatilis, and Enterobacter sp. were the major bacteria in the IR silage, indicating that alcoholic fermentation may be due to the activity of enterobacteria. Staphylococcus sciuri and Bacillus pumilus were detected when IR silage was spoiled, whereas between aerobically stable and unstable silages, no differences were seen in the bacterial community at silo opening. Lactococcus lactis was a representative bacterium, although acetic acid was the major fermentation product in the GG silage. Lactobacillus plantarum, Lactobacillus brevis, and Morganella morganii were suggested to be associated with the increase in acetic acid due to prolonged storage. Enterobacter cloacae appeared when the GG silage was spoiled. In the WM silage, no distinctive changes due to prolonged ensiling were seen in the bacterial community. Throughout the ensiling, Weissella paramesenteroides, Weissella confusa, and Klebsiella pneumoniae were present in addition to L. plantarum, L. brevis, and L. lactis. Upon deterioration, Acetobacter pasteurianus, Klebsiella variicola, Enterobacter hormaechei, and Bacillus gibsonii were detected. These results demonstrate the diverse bacterial community that evolves during ensiling and aerobic spoilage of IR, GG, and WM silages.

Growth Inhibition of Listeria monocytogenes by Weissella spp. from Kimchi Through Real-time PCR (실시간 정량 PCR을 통한 김치 유래 Weissella spp.에 의한 Listeria monocytogenes 생육 억제)

  • Lee, Young-Duck;Kim, Dae-Yong;Park, Jong-Hyun
    • Journal of Food Hygiene and Safety
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    • v.30 no.1
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    • pp.103-108
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    • 2015
  • Weissella spp. from traditional Korean foods of Kimchi were isolated and characterized against food-borne pathogenic Listeria monocytogens. The isolates were identified as W. cibaria 0D17 and W. confusa 0D23 from Kimchi by the biochemical characteristics and 16S DNA sequencing. The culture solutions of the isolates adjusted to pH 7.0 showed L. monocytogens inhibition. To analyze the quantitative detection of L. monocytogenes, real-time PCR was performed according to the SYBR Green I method. The isolates grew well and L. monocytogens did not grow during the co-culture with those strains at $37^{\circ}C$. Therefore, W. cibaria 0D17 and W. confusa 0D23 might be the candidates as the functional lactic acid bacteria for improving food safety.

Quality Characteristics of Yakju fermented with Paddy Rice (Byeo) Nuruk Yakju (벼누룩으로 제조한 약주의 품질 특성)

  • Jeon, Jin-Ah;Kim, Min-Seong;Ko, Jae-Yoon;Jeong, Seok-Tae
    • Journal of the East Asian Society of Dietary Life
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    • v.27 no.2
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    • pp.159-167
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    • 2017
  • In this study, quality characteristics of yakju fermented with byeo-nuruk prepared using rice, wheat, and water were investigated. Five different mixture ratios were considered for byeo-nuruk preparation. A comparative analysis of commercial yakju and byeo-nuruk yakju was also performed. The results showed no significant differences in pH, total acidity, and total soluble solids of byeo-nuruk yakju immediately following fermentation. The byeo-nuruk yakju alcohol content increased with increasing wheat proportion. Lactic and succinic acid were the major organic acids of byeo-nuruk yakju, and the major volatile components were isoamyl alcohol and linalool. Yakju prepared using material D had the highest volatile component content and high preference evaluation scores for taste and overall acceptability. Compared to commercial yakju, byeo-nuruk yakju had less total acidity, soluble solids, and volatile acids, whereas its pH level and amino acid content were higher. No significant differences were observed between commercial yakju and byeo-nuruk yakju in terms of sensory evaluation.