• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.199-215
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• 1998

In order to determine the effect of tomato(Lycopersicon escylentnm mill ssp.) on the yogurt quality, skim milk powders were added with tomato juice of 0%, 1%, 3%, 5% and fermented by mixed culture(Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. The results were summarized as follows: 1. Addition of tomato juice in skim milk decreased pH(4.3) and increased acidity(0.93%) more than control did(pH 4.6, titratable acidity 0.85%). By the addition of tomato juice, acid production was increased and pH was decreased in proportion to concentrations of tomato juices added to skim milk. 2. The number of lactic acid bacteria in yogurts added with tomato juice ($4.59{\times}10^{12}cfu/ml$) more increased than those in control yogurt($8.96{\times}10^{11}cfu/ml$). By the addition of tomato juice, the number of lactic acid bacteria counts increased in proportion to concentration of tomato juices added to skim milk. 3. As fermentation time goes by, the Brix degree sugar content in skim milk were decreased more rapidly than control. 4. The pH, titratable acidity, Brix degree and lactic acid bacteria were not significantly changed for all yogurts for the storing at $5^{\circ}C$ for 14 days. 5. In yogurt fermentation, addition of tomato juice with glucose (1% tomato juice + 4% glucose, 3% tomato juice + 2% glucose, 5% tomato juice + 0% glucose) decreased pH and increased acidity than control(5%glucose) did. In addition of tomato juice, acidity was increased and pH was decreased in proportion to concentration of tomato juices added to skim milk. 6. In yogurt fermentation, the number of lactic acid bacteria of yogurt added with tomato juice(1% tomato juice+4% glucose, 3% tomato juice+2% glucose, 5% tomato juice+0% glucose) increased than control(5% glucose). In addition of tomato juice, the number of lactic acid bacteria increased in proportion to concentration of tomato juices added to skim milk. 7. As fermentation time goes by, the Brix degree were decreased more rapidly than control(5% glucose). By the change of pH, titratable acidity, Brix degree and lactic acid bacteria, in yogurt fermentation, we definited that the promotive effect of tomato(Lycopersicon escylentnm mill ssp.) on the yogurt.

• Food Science of Animal Resources
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• v.23 no.3
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• pp.250-261
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• 2003

This experiment was carried out to examine the fermentation properties of yogurt with Lycii fructus, Lycii folium and Lycii cortex powder, and extract additives at concentrations of 0.5, 1.0, 2.0, 4.0, and 6.0%. Lactic acid bacteria was used in a mixed starter culture of Streptococcus salivarius ssp. thermophilus(ST36) and Lactobacillus delbrueckii ssp. bulgaricus(LB12). When the boxthorn was added with extract types, the changes of pH, acidity and lactic acid bacteria counts of yogurt during the fermenation of 3 hours were pH 5.64, titratable acidity 0.85%, 5.80xl0$\^$6/cfu/ml of viable cell counts for control yogurt, whereas those were pH 4.10∼5.06, titratable acidity 0.98∼1.27%, 1.80∼9.60x10$\^$7/ cfu/ml of viable cell counts for Lycii fructus extract yogurt. The lactose hydrolysis ratio was better for 1.0% Lycii fructus extract yogurt(42.00%) and 1.0% Lycii folium extract yogurt(41.46%) than for control yogurt(28.40%). Also, content of lactic acid of 1.0% Lycii fructus(11.9 times) and 1.0% Lycii folium extract yogurt(10.6 times) produced more than control yogurt(7.3 times). The viscosity of yogurt was better for boxthorn extract yogurt(1,027∼1,382 cps) than for control yogurt(975cps). The sensory scores of color, taste and overall acceptability of yogurt with 0.5, and 1.0% Lycii fructus extract additive were better than other groups. The yogurts made with increased Lycii fructus extract concentration(0.5∼6.0%), showed the increase of lactic acid, titratable acidity, number of lactic acid bacteria, viscosity and lactose hydrolysis rate compared to the treatments of 0.5, 1.0, 2.0, and 4.0% Lycii folium and Lycii cortex extract and powder yogurt. We gained excellent results from the yogurt to which Lycii fructus extract was added with 0.51.0% concentration.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.31-43
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• 2014

This experiment evaluated the interaction effect of extreme heat diet(EHD), inverse lighting, and cool water on the growth performance of broiler chickens under extreme heat stress. There were 4 experimental groups (T1: EHD 1, 10:00-19:00 dark, 19:00-10:00 light, cold water $9^{\circ}C$; T2: EHD 2, 10:00-19:00 dark, 19:00-10:00 light, cold water $9^{\circ}C$; T3: EHD 1, 09:00-18:00 dark, 18:00-09:00 light, cold water $14^{\circ}C$; T4: EHD 2, 09:00-18:00 dark, 18:00-09:00 light, cold water $14^{\circ}C$), each group composed of 25 broilers and the experiment was repeated 3 times. EHD 1 contained soybean oil, molasses, methionine and lysine. EHD 2 contained all nutrients of EHD 1 and vitamin C additionally. As a result, T1 and T2 displayed higher body weight increase and diet intake compared to T3 and T4 (p<0.05). The weights of their liver and gizzard were similar but the weights of the thymus and bursa F were higher for T1 and T2 compared to that of T3 and T4 (p<0.05). It was observed that T1 and T2 displayed higher concentrations of blood triglyceride, total cholesterol, HDL-C and blood sugar compared to that of T3 and T4 but LDL-C level was higher for T3 and T4 compared to that of T1 and T2 (p<0.05). T1 and T2 displayed higher levels of immunity substances such as IgG, IgA and IgM compared to T3 and T4 but the blood level of corticosterone displayed to be lower for T1 and T2 compared to T3 and T4 (p<0.05). The T1 and T2 contained a higher amount of fecal lactobacillus compared to that of T3 and T4 but the T3 and T4 contained a higher amount of fecal E. coli, total aerobic bacteria, coliform bacteria compared to that of T1 and T2 (p<0.05). T1 and T2 displayed higher concentrations of cecal acetic acid, propionic acid and total short chain fatty acids compared to T3 and T4 but T3 and T4 displayed higher concentrations of butyric acid, isobutyric acid, valeric acid and isovaleric acid compared to T1 and T2 (p<0.05). These results have been observed that broiler chickens exposed to extreme heat stress with feeding EHD, inverse lighting and cold water would improve blood lipid, and elevate the production of immunity substance, beneficial microorganisms, and short chain fatty acids. This provision would also reduce the blood sugar consumption rate as energy sources and these effects will improve the growth performance of the broilers exposed to extreme heat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.435-443
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• 2011

In this study, we evaluated the effects of harvey powder on the fernentation of Yulmoo Kimchi, by measuring sensory, physicochemical, and microbiological properties during fermentation up to 31 days. The Yulmoo Kimchi, with various levels [0, 0.1, 0.2, 0.3, 0.4% (w/w)] of harvey powder, was fermented at $10^{\circ}C$. The product containing the control evidenced the highest scores for appearance and smell. Taste, carbonated taste, texture and overall acceptability were highest in the 0.1% harvey powder and control. During fermentation, titratable acidity increased while pH gradually decreased. Reducing sugar showed no difference at initial fermentation and then steadily decreased. Total vitamin C was gradually decreased during fermentation and reduced sharply after 10 days, and then almost maintained. Total polyphenol content was the highest in the 0.3% harvey powder on day 0 and maintained in all samples thereafter. Antioxidant effect of the Yulmoo Kimchi with 0.1% harvey powder was shown to be the highest. Also, the time required to achieve maximum levels of lactic acid bacteria, as determined by log numbers of cells and total viable cells, were more delayed in the experimental groups with added harvey powder than in the controls. Our results indicated that the Yulmoo Kimchii with below 0.1% added harvey powder was acceptable.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.583-592
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• 2001

This study was undertaken to evaluate the clinical effect of inhibiting plaque formation of Lactococcus lactis 1370, a acid producing bacterium residing in the mouth. 30 children were asked to use 10ml of control mouth-wash and mouthwash containing Lactococcus lactis 1370. The plaque index and plaque area rate at 24h and 48h after the use of the mouthwashes were measured. And the number of Lactococcus lactis 1370 was counted at 1h, 3h, and 6h in the mouth. The results are as follow. 1. The mean plaque index at 24h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 2.43 and 2.06, respectively. The inhibiting rate of plaque formation was 15% (P<0.05). 2. The mean plaque index at 48h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 2.95 and 2.17, respectively. The inhibiting rate of plaque formation was 26%, showing more decrease than at 24h(P<0.05). 3. The mean plaque area rate at 24h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 21.2% and 15.6%, respectively. The inhibiting rate of plaque formation was 26% (P<0.05). 4. The mean plaque area rate at 48h after the use of the control mouthwash and the mouthwash containing Lactococcus lactis 1370 were 33.0% and 17.8%, respectively. The inhibiting rate of plaque formation was 46% (P<0.05). 5. The number of Lactococcus lactis 1370 in the mouth decreased significantly from mouthwashing to 3h, but increased slightly between 3h and 6h. As seen with the above results, we think that using the mouth wash with Lactococcus lactis 1370 would prevent the formation of plaque in the mouth and can be an effective method to prevent dental caries and periodontal disease.

• Food Science and Preservation
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• v.24 no.6
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• pp.865-870
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• 2017

Yogurt is produced by fermentation of milk using bacteria known as "yogurt cultures". Most of these bacteria are probiotics such as Lactobacillus delbrueckii subsp. bulgaricus, Lb. rhamnosus, Streptococcus thermophilus, and Bifidobacterium. The domestic fermented milk market is increasing, and about 30 companies are producing yogurt. The purpose of this study was to analyze the quality characteristics of domestic commercial liquid yogurt. Total 30types of commercial yogurts were sampled and their physicochemicial properties, including pH, sugar content, acidity, viscosity, and microbial characteristics of lactic acid bacteria counts, were measured. Commercial liquid type yogurt showed a pH of 4.5, sugar content of 7.4-21.2%, total acid content of 0.4-0.9%, and viscosity of 0.1-250 cP. In terms of microbial populations, lactic acid bacteria counts were 7.2-11.3 log CFU/mL and anaerobic lactic acid bacteria counts were 8.0-11.5 log CFU/mL. The quality characteristics differed depending on the constituents of the sample and the microorganisms used. These results are related to the quality characteristics of yogurts and are useful for identifying new trends in the domestic fermented milk industry.

• Journal of the Korean Society of Food Culture
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• v.19 no.1
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• pp.30-42
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• 2004

In order to examine the effect of the combination of fermented temperature and time on Baechu kimchi in a kimchi refrigerator, Baechu kimchi was fermented at four different modes of the fermentation temperature and time for 16 weeks and analyzed the properties of Baechu kimchi. The pH, Baechu kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and Baechu kimchi fermented at $5^{\circ}C$ for 6 days/stored at $-1^{\circ}C$, decreased rapidly during first week and then decreased very slowly. The hardness and the chewiness of Baechu kimchi fermented at high temperature were higher and the values were decreased when the fermentation continued. In sensory evaluation, carbonated flavor in Baechu kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ was the best after 4 weeks, and Baechu kimchi fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$ was the best after 8 weeks. The scores for sourness were the highest on 8 weeks and 12 weeks in kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$, respectively. The sensory scores for overall acceptability were the best on 4 weeks and 8 week in kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$, respectively. Total microbial count was increased as the temperature of fermentation increased. Counts of Leuconostoc spp. reached to the highest after 6 days and counts of Lactobacillus spp reached to the highest after 5 days in kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$. From these results, it was concluded that it required 4 weeks to eat most edible Baechu kimchi in kimchi refrigerator fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$, and 8 weeks to eat most edible Baechu kimchi in kimchi refrigerator fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.345-350
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• 2014

The aim of this study was to investigate the effect of high temperature on the viability of probiotic organisms (Bacillus subtilis, Lactobacillus plantarum, and Saccharomyces cerevisiae) mixed with animal feed under controlled conditions by simulating a farm feed bin in the summer. Following inoculation of probiotics into the feed, the pH and probiotic viability were monitored during an 8-day incubation at room temperature. Sterile and non-sterile feeds displayed different patterns of pH changes, with increased pH in non-sterile feed at 2 days, but a pattern of decreasing pH at 4 days. The viabilities of S. cerevisiae and B. subtilis after mono/co-inoculation were maintained without substantial changes during the incubation, whereas L. plantarum viability tended to decline. In both non-sterile and sterile feeds, the probiotics were maintained or grew without any antagonistic effects. Probiotic viability was also tested upon a shift to high temperature ($60^{\circ}C$). There was no distinct change in pH between sterile and non-sterile feeds after the temperature shift. L. plantarum and S. cerevisiae could not survive at the high temperature, whereas B. subtilis displayed normal growth, and it inhibited the growth of contaminant microbes. Fungal growth was not observed in non-sterile feed 2 days after supplementation with B. subtilis. Therefore, heat resistant B. subtilis could be safely used in feed bins to inhibit microbial contamination, even at high temperatures. The prevention of elevated temperature in feed bins is necessary for the utilization of L. plantarum and S. cerevisiae during the summer season.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1386-1396
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• 2017

The purpose of this study was to determine the optimum Platycodon grandiflorum root concentrate (PGRC, $65^{\circ}Brix$), fermented P. grandiflorum root extract by Lactobacillus plantarum (FPGRE, $2^{\circ}Brix$), and cactus Chounnyouncho extract (Cactus-E, $2^{\circ}Brix$) for preparation of PGRC stick product with FPGRE using response surface methodology (RSM). The experimental conditions were designed according to a central composite design with 20 experimental points, including three replicates for three independent variables such as amount of PGRC (8~12 g), FPGRE (0~20 g), and Cactus-E (0~20 g). The experimental data for the sensory evaluation and functional properties based on antioxidant activity and antimicrobial activity were fitted with the quadratic model, and accuracy of equations was analyzed by ANOVA. For the responses, sensory and functional properties showed significant correlation with contents of three independent variables. The results indicate that addition of PGRC contributed to increased bitterness and acridity based on the sensory test and antimicrobial activity, addition of FPGRE contributed to increased antioxidant activity and antimicrobial activity, and addition of Cactus-E contributed to increased fluidity based on the sensory test, antioxidant activity, and antimicrobial activity. Based on the results of RSM, the optimum formulation of PGRC stick product was calculated as PGRC 8.456 g, FPGRE 20.00 g, and Cactus-Ex 20.00 g with minimal bitterness and acridity, as well as optimized fluidity, antioxidant activity, and antimicrobial activity.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.381-390
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• 2008

Two experiments were conducted to investigate effects of molasses addition to silage materials in ensiling Socheongryongtang meal on the nutritive quality of silage, palatability and various ruminal parameters in Korean native goats. In Experiment 1, Socheongryongtang meal silage was produced by the addition of 0, 0.5, or 1.0% molasses and stored for 40 days at room temperature. There were three replicates per treatment. Lactic acid contents of Socheongryongtang meal silage containing molasses(0.5 and 1.0%) were significantly(p<0.05) higher than that of the control(0%). However, the pH and butyric acid contents of Socheongryongtang meal silage containing molasses(0.5 and 1.0%) were lower than those of the control(0%). In addition, molasses(0.5 and 1.0%) increased the number of lactobacillus, but decreased the number of fungi in Socheongryongtang meal silage. In vitro dry matter disappearance tended to increase by molasses addition. In Experiment 2, three 1.5-yr-old Korean native female goats were employed in cross-over design to measure the palatability and various ruminal parameters of Socheongryongtang meal silage. Feed intake of Socheongryongtang meal silage containing molasses(0.5 and 1.0%) for 30 min significantly higher than that of control(0%). Silmilar trend was found when the feed intake was measured for 6 hr. In various ruminal parameters, molasses addition to silage materials increased propionic acid(P) and total volatile fatty acid contents, but decreased pH, acetic acid (A), and butyric acid. The A/P ratio was the lowest in 1.0% molasses treatment group. It is concluded that molasses addition in ensiling Socheongryongtang meal could enhance its nutritional quality and lengthen storage period. Also the palatability of silage was improved by the addition of molasses.