• Journal of Microbiology and Biotechnology
• /
• v.27 no.11
• /
• pp.2019-2027
• /
• 2017

Recently, cabbage kimchi has occasionally been associated with the foodborne diseases of enteric viruses such as human norovirus (HuNoV). This study aimed to evaluate the correlation between microbial/physicochemical properties and persistence of HuNoV in experimentally contaminated cabbage kimchi fermented and stored at $4^{\circ}C$ or $10^{\circ}C$ for 28 days. Changes in organic acid content, lactic acid bacteria (LAB), acidity, pH, and salinity were analyzed. The recovery of structurally intact HuNoV was examined for up to 28 days post-inoculation, using a NoV GII.4 monoclonal antibody-conjugated immuno-magnetic separation method combined with quantitative real-time reverse transcription polymerase chain reaction. On day 0, LAB loads were $4.70log_{10}$ colony forming units/g and HuNoV GII.4 titers were $2.57log_{10}\;genomic\;copies/{\mu}l$, at both temperatures. After 28 days, intact HuNoV titers decreased to 1.58 ($4^{\circ}C$) and $1.04(10^{\circ}C)log_{10}\;genomic\;copies/{\mu}l$, whereas the LAB density increased. This correlated with a gradual increase in lactic acid and acetic acid at both temperatures. Our findings support a statistical correlation between changes in physicochemical properties and the recovery of structurally intact HuNoV GII.4. Moreover, we determined that the production of organic acid and low pH could affect HuNoV GII.4 titers in cabbage kimchi during fermentation. However, HuNoV GII.4 was not completely eliminated by microbial/physicochemical factors during fermentation, although HuNoV GII.4 was reduced. Based on this, we speculate that the persistence of HuNoV GII.4 may be affected by the continually changing conditions during kimchi fermentation.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.37 no.4
• /
• pp.350-357
• /
• 2017

Near infrared spectroscopy (NIRS) is a rapid and accurate method for analyzing the quality of cereals, and dried animal forage. However, one limitation of this method is its inability to measure fermentation parameters in dried and ground samples because they are volatile, and therefore, respectively lost during the drying process. In order to overcome this limitation, in this study, fresh coarse haylage was used to test the potential of NIRS to accurately determine chemical composition and fermentation parameters. Fresh coarse Italian ryegrass haylage samples were scanned at 1 nm intervals over a wavelength range of 680 to 2500 nm, and optical data were recorded as log 1/reflectance. Spectral data, together with first- and second-order derivatives, were analyzed using partial least squares (PLS) multivariate regressions; scatter correction procedures (standard normal variate and detrend) were used in order to reduce the effect of extraneous noise. Optimum calibrations were selected based on their low standard error of cross validation (SECV) values. Further, ratio of performance deviation, obtained by dividing the standard deviation of reference values by SECV values, was used to evaluate the reliability of predictive models. Our results showed that the NIRS method can predict chemical constituents accurately (correlation coefficient of cross validation, $R_{cv}^2$, ranged from 0.76 to 0.97); the exception to this result was crude ash ($R_{cv}^2=0.49$ and RPD = 2.09). Comparison of mathematical treatments for raw spectra showed that second-order derivatives yielded better predictions than first-order derivatives. The best mathematical treatment for DM, ADF, and NDF, respectively was 2, 16, 16, whereas the best mathematical treatment for CP and crude ash, respectively was 2, 8, 8. The calibration models for fermentation parameters had low predictive accuracy for acetic, propionic, and butyric acids (RPD < 2.5). However, pH, and lactic and total acids were predicted with considerable accuracy ($R_{cv}^2$ 0.73 to 0.78; RPD values exceeded 2.5), and the best mathematical treatment for them was 1, 8, 8. Our findings show that, when fresh haylage is used, NIRS-based calibrations are reliable for the prediction of haylage characteristics, and therefore useful for the assessment of the forage quality.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.36 no.1
• /
• pp.23-28
• /
• 2016

The present study was carried out to explore the potential effects of novel lactic acid bacteria Pediococcus penticeous KCC-23 (KCC-23) and Lactobacillus plantarum KCC-24 (KCC-24) on rye haylage fermentation at National Institute of Animal Science, Cheonan province in Korea. The experiment contains three different groups such as control without lactic acid bacteria, rye haylage with KCC-23 and rye haylage KCC-24. After experimental periods, the content of crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), the activity of total digestible nutrient (TDN) and In-vitro digestibility (IVD) was similar in control and LAB treated haylage (p<0.05). The pH was reduced in KCC-23 and KCC-24 treated rye haylage as compared to control (p<0.05). The lactic acid concentration in haylages was increased by L. plantarum KCC-23, and KCC-24 supplement. Whereas, the less amount of acetic acid and butyric acid was noted in KCC-23 and KCC-24 treated haylage as compared with control (p<0.05). The KCC-23 and KCC-24 were dominantly grown in experimental haylage as compared with control. It indicates, the addition of KCC-23, and KCC-24 enhances fermentation quality of haylages as compared control. The present study suggests that KCC-23 and KCC-24 are potent strains that were improving the fermentation process in rye haylage

• Journal of agriculture & life science
• /
• v.43 no.6
• /
• pp.67-75
• /
• 2009

This study was conducted to investigate the effect of herbal (Obtusifolia, Cinnamon, Chinese pepper, Licorice) extracts on the rumen fermentation in vitro. Comparing to the control, in vitro dry matter digestibility was significantly (P<0.05) decreased at zero hour in the Cinnamon and the Chinese pepper, and at three hour after supplementation in the Licorice. The ratio of volatile fatty acids were significant (P<0.05) differences at 3 hour after fermentation only, acetic acid was higher (P<0.05) in the control compare to the herbal extract treatments, but the ratios of butyrate, iso-butyrate, iso-valerate and valerate were lowest in the control. The growth rate of rumen microbes in vitro was significantly (P<0.05) higer in the herbal extract treatments excluding the Obtusifolia than the control during three hour fermentation, but was not significant difference among treatments in the other fermentation times. From above results, even though the extracts of Cinnamon, Chinese pepper and Licorice inclined to inhibit the activity of rumen microbes during early fermentation period, but did not affect on the growth rate of rumen microbes in vitro.

• Journal of Naturopathy
• /
• v.12 no.2
• /
• pp.67-76
• /
• 2023

Background: Kombucha, known domestically as black tea mushroom, is a traditional fermented beverage from Northeast Asia made by fermenting a mixture of black tea extract and fungus. It is known for its high detoxifying, antimicrobial, and antioxidant activities, as well as its effects on relieving arthritis pain, reducing blood pressure, and addressing gastrointestinal or metabolic diseases. Purpose: This study aims to identify the main microbial system of Kombucha fermentation. Methods: The 16sRNA sequencing method was applied to analyze the microbial composition of Kombucha fermentation. Results: Bacterial, yeast, and fungi groups were identified. Through the identification of commercial Kombucha strains, it was confirmed that the bacteria in the Kombucha fermentation liquid and the pellicle were predominantly microbes from the Gluconacetobacter and Gluconobactor, which are involved in the fermentation of Kombucha. Among the yeasts, Sacchromycetes class, Starmerella bacillaris were identified with the highest expression rate. It was confirmed that the main microbial system fermenting Kombucha is SCOBY(Symbiotic Culture of Bacteria and Yeast), and that different strains are prominently expressed compared to the foreign Kombucha, which is mainly composed of Acetobacter acetic bacteria and Zygosaccharomyces yeast commonly. Conclusions: This study highlights the complexity and diversity of the microbial ecosystem in Kombucha fermentation, and comparative analysis with commercial strains reveals the potential for diversification of SCOBY to improve the functional properties of Kombucha. Future studies will investigate microbial interactions within the SCOBY and their impact on the health-promoting properties of Kombucha.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.6
• /
• pp.511-518
• /
• 1985

As one of the sensory factors for characterizing food quality, volatile compounds have been particularly contributed to sensory evaluation of fermented sea foods in Korea. But no chemical investigation of the volatile compounds of fermented anchovy as one of the most favored fermented sea food products has been reported. Accordinglry, for a series study of processing of low salt fermented sea foods, changes in volatile compounds and fatty acid composition of fermented anchovy with low salt contents ($4\%$ of salt contents) were experimented fermentation comparing with conventional fermented anchovy ($20\%$ of salt contents). Total lipid of raw anchovy was composed of $77.6\%$ of neutral lipid, $22.1\%$ of phospholipid and $0.3\%$ of glycolipid. And polyenoic acid was held $39.8\%$ of fatty acid composition of total lipid and the major fatty acids in those were $C_{22:6},\;C_{20:5}$. During the fermentation of anchovy saturated fatty acid ($C_{16:0},\;C_{18:0},\;C_{l4:0}$) and monoenoic acid ($C_{16:1},\;C_{18:1}$) increased while polyenoic acid ($C_{22:6},\;C_{20:5}$) decreased greatly. Thirty-eight kinds of volatile component from the whole volatile compounds obtained from fermented anchovy after 90 days fermentation were identified, and composed of some alcohols (8 kinds), carbonyl compounds (9 kinds), hydrocarbons (8 kinds) and fatty acids (8 kinds). During fermentation 8 kinds of volatile acids, 5 kinds of amines, 9 kinds of carbonyl compounds were also detected. Those volatile acids such as acetic acid, isovaleric acid, propionic acid, n-butyric acid were the major portion of total volatile fatty acids of 60 days fermented anchovy prepared with low salt contents. On the other hand, carbonyl compounds such as ethanal, 3-methyl butanal, hexanal, 2-methyl propanal were the major ones, while TMA held the most part of volatile amines in fermented anchovy with low salt contents after 60 days. Conclusively, there was little difference in composition of volatile components, but merely a little difference in content of those between low salt fermented anchovy and conventional fermented ones.

• Korean Journal of Food Science and Technology
• /
• v.42 no.1
• /
• pp.56-62
• /
• 2010

Quality characteristics such as alcohol, acid, and sugar contents of takju brewing mashes prepared using several yeasts were investigated during 12-days of fermentation. Among the yeasts examined, S. cerevisiae led to the highest level of ethanol (10.2-13.4%) and total minor alcohols (0.729-0.831 mg/mL). Regardless of the yeasts used, the acidity showed drastic changes (pH from 3.4-4.2 down to 2.4-2.7) during the first 2 days, and displayed negligible changes from day 4. The total acid contents rapidly increased to the first 4 days of fermentation and leveled off from 4 to the end of fermentation period. The common organic acid components were lactic, succinic and acetic acids. The total and reducing sugar contents varied depending on the yeasts used, with mashes prepared using S. coreanus and S. rouxii producing the maximum total sugar contents (5.43-5.5%) at the end of fermentation. The reducing sugar showed its maximum (7.53-14.89%) at day 2, after which it decreased to its minimum levels (3.04-4.52%). The common free sugar components were glucose and fructose, while S. ellipsoideus led to a higher free sugar level (0.35-5.29%).

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.1
• /
• pp.79-86
• /
• 2012

This study was performed to investigate the physiochemical properties and anti-diabetic effect of yacon vinegar by two-step fermentation. Yacon was matured at room temperature for 20 days. The sugar content of yacon juice prepared from mature yacon was approximately $14^{\circ}Brix$. In the first stage, yacon wine was produced from the juice at $28^{\circ}C$ for 6 days. In the second stage, acetic acid fermentation was conducted at $30^{\circ}C$ and 200 rpm for 6 days to produce yacon vinegar with 4.75% acidity. The major free sugars of yacon vinegar were glucose and fructose at 2,072.12 mg% and 463.95 mg%, respectively. The acetic acid content was the highest of the major organic acids at 3,881.44 mg%. The total free amino acid content was 62.88 mg% with the main free amino acids being proline, ${\gamma}$-amino-n-butyric acid and ornithine. The major minerals of yacon vinegar were Ca, K and Mg. The in vivo anti-diabetic activity of yacon vinegar was investigated in high-fat diet (HFD)/streptozotocin (STZ)-induced diabetic mice. Diabetic mice were administered orally with 10% yacon juice and two yacon vinegars (5% and 10%) at a dose of 7 mL/kg body weight once per day for 4 weeks. Five% yacon vinegar improved the fasting blood glucose levels and glucose tolerance test significantly compared to the diabetic control group (p<0.05). Yacon vinegar increased the pancreatic C-peptide concentration in a dose-dependent manner. These results show that 5% yacon vinegar has a more potent effect on ameliorating hyperglycemia than 10% yacon juice.

• The Korean Journal of Food And Nutrition
• /
• v.25 no.1
• /
• pp.90-98
• /
• 2012

With the addition of ethanol to wax gourd extract and by acetic fermentation, 5.0% acidity vinegar was produced. After putting 10% extract(10% concentration) of Chrysanthemum zawadskii in this, and by dissolving shell, Chrysanthemum zawadskii-pearl vinegar was produced. When a 1% of ark shell, oyster shell, or ear shell was added to wax gourd vinegar, 95.6~98.4% of the shell dissolved, and when a 2% content of shell was added, 97.2~98.4% was dissolved. The acidity of vinegar which dissolved 1% shell was pH 3.0~3.17, and the acidity of vinegar which dissolved 2% shell was pH 1.11~ 1.20. The pH values of vinegar which dissolved 1%, and 2% shell contents were 4.54~4.55, and 4.86~4.95, respectively. When 1% shell was dissolved, the acidity was higher than that of commercial vinegar, with a high pH value and low level of free acid. This shows that when Chrysanthemum zawadskii 1% is added during acetic acid fermentation, the inhibition was 44.4%, and 22.2% respectively. In this regard, Chrysanthemum zawadskii should be added after the fermentation of acetic acid. The calcium content of 1% shell vinegar is 0.4%, and that of 2% vinegar is 0.78%. Non-heated native wax gourd shows an angiotensin converting enzyme inhibition rate of 21.7%, an antioxidant activity of 5.23%, and a tyrosinase inhibition rate of 5.5%. In the case of heated-extracted wax gourd, the angiotensin converting enzyme inhibition rate was 16.1%, superoxide dismutase activity was 20.5%, antioxidant activity was 23.2%, and the tyrosinase inhibition rate was 7.1%. Also, in the case of Chrysanthemum zawadskii, the angiotensin converting enzyme inhibition rate was 28.8%, the xanthine oxidase inhibition rate was 28.2%, the superoxide dismutase activity was 14.5%, the antioxidant activity was 3.2%, and the tyrosinase inhibition rate was 9.2% Data also revealed that when a 10% sample of the heated-wax gourd extract was added to A549 human lung cancer epithelial cells of, the number of cancer cells declined by 80% in 72 hours, When a 10% native extract was added, the number of cells declined by, 74% in 48 hours, and when a heated-extract of Chrysanthemum zawadskii was added, 100% of the cells died after 72 hours.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.4
• /
• pp.602-609
• /
• 2015

In this study, for modernization of Korean traditional fermented milk, Tarak was made using four kinds of commercial Makgeolli based on the ancient cookbook Suwoonjabbang. Samples of Tarak were periodically collected during 24 h of fermentation at $37^{\circ}C$. After fermentation, changes in pH, titration acidity, and viscosity were analyzed. Fermentation metabolites, including organic acids and free sugars, were analyzed by HPLC. Numbers of yeast and lactic acid bacteria during 24 h of fermentation were measured. The pH of Tarak significantly decreased (P<0.01), whereas its acidity significantly increased (P<0.01) during fermentation. The viscosity increased during 8~24 h of fermentation until curd was separated in Tarak. The level of ethanol increased from 0.37~0.52 mg/mL to 0.51~0.71 mg/mL during 24 h of fermentation. Lactic acid and lactose were the major organic acid and free sugar in Tarak, respectively. The number of lactic acid bacteria increased from 5.23~6.25 log CFU/mL to 9.87~10.41 log CFU/mL at the beginning during 24 h of fermentation. The number of yeast increased from 5.14~6.47 log CFU/mL to 6.99~7.73 at the beginning during 24 h of fermentation at $37^{\circ}C$. The major strains of Tarak were Pediococcus acidilactici, Lactobacillus fermentun, Lactobacillus curvatus, and Saccharomyces cerevisiae. Therefore, we concluded that Tarak was a fermented milk by both lactic acid bacteria and yeast, which was similar to koumiss or kefir.