• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1037-1043
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• 2008

In this experiment, citrus juice was fermented by Gluconacetobacter hansenii TF-2, an isolate from tea fungus to develop a new type of acidic beverage. The juice broth is made by fermenting of $11{\sim}17%$ (v/v) juice and sweetened with sucrose (initial sucrose $10^{\circ}Brix$). The fermentation by G. hansenii TF-2 was initiated by adding 5% (w/v) of seed gel (pellicle, tea fungus) which was previously cultured in the same medium (fresh juice broth) and the fermentation was carried out in a dark incubator at $28{\sim}30^{\circ}C$ for about 15 days. During the fermentation a pellicle grew on the surface of the fermenting fluid and acids were produced. Fermented fluid (beverage) was centrifuged at 7,000 rpm for 15 min for further analyses. The highest amount of the other metabolites including organic acids were observed in 5 to 10 days. Major acids were acetic acid (fermented citrus beverage, CB). After 15 days of fermentation, organic acid content such as acetic acid in fermented beverage was measured to be $183.5{\sim}186.6\;ppm$. Free sugars content in CB were 56.8%, 35.1%, 40.7% and 63.2% of unfermented sucrose, glucose, fructose and sorbitol, respectively. When the growth rate of inhibitory effect of the fermented beverage was measured by using several species of food-related bacteria, the beverage fermented with CB exhibited the strongest inhibition against gram-negative (E. coli and Sal. Typhimurium). Its inhibition rate was between $71.9{\sim}94.0%$ at CB. Fermented beverage has shown effectiveness for antimicrobial activity against some species of food-related bacteria.

• Food Science and Preservation
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• v.18 no.1
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• pp.46-52
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• 2011

Wild grape juice was fermented by Gluconacetobacter hansenii TF-2 isolated from tea fungus, to develop a new acidic beverage (fermented wild grape beverage, WGB). Broth was prepared by fermentation of 11~17% (v/v) juice, and sweetened with sucrose (initial sucrose level: $10^{\circ}$ Brix). Fermentation was initiated by addition of 5% (w/v) seed gel (the pellicle of the tea fungus) which had been previously cultured in the same medium (freshjuice broth), and fermentation proceeded in the dark at $29{\pm}1^{\circ}C$ for about 15 days. The major acids produced were succinic acid, malic acid, and acetic acid. After 15 days of fermentation, the organic acid content (principally succinic acid) was 49.6 ppm in WGB 11 and 77.4 ppm in WGB 17. The free sugar content of WGB was 1063.6-1082.5 mg/mL, composed of unfermented fructose, glucose, and sucrose, in that order. The microbial inhibitory effects of the fermented beverage were most apparent when Gram-negative bacteria (Escherichia coli and Salmonella typhimurium) were tested; the inhibition rate was 34.46-88.00%. The new fermented beverage thus displays effective antimicrobial activity against some species of bacteria.

• Journal of Life Science
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• v.6 no.1
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• pp.56-65
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• 1996

Black tea extractbsupplemented with 10% sucrose was fermented by fungus at 30$\circ$C. A pellicle thick as 7$\sim$8 mm covered entire surface of the medium and the wxtract converted to acidic beverage(abbreviated below as fermented black tea) by 14 days of fermentation. It was a kind of acetic acid fermentation depending on symbiotic microorganisms. During the fermentation strains of yeasts(Saccharomyces cerevisiae and Eeniella sp.)and bacteria(Bacillus subtilis, Kurthia zopfii, Gluconobacter oxydans and Deinicoccus sp.) were isolated from aqueous layer. Contrastly to it, a bacterial strain(Acetobacter aceti) was isolated from thick pellicle. The bacteria grew as a viscouse cluster on solid agar medium differently from usual strains of A. aceti. Fermented black tea had sweet-sour taste and sweet smell.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1358-1364
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• 2000

A mixed culture of bacteriocin-producing lactic acid bacteria and yeast was used to prepare unique fermented fruit and vegetable beverage which contains bacteriocin. Fruit and vegetable broth fermented by Lactococcus lactis 11454 showed inhibitory activity against foodborne pathogens such as Listeria monocytogens and Staphylococcus aureus, and Streptococcus mutans which is a major causative agent for dental caries. Bacteriocin was detected at the end of fermentation of fruit and vegetables and its antimicrobial activity was stable for 5 weeks during storage at $4^{\circ}C$. These results suggest that the presence of bacteriocin in beverages during fermentation and storage will provide a safeguard against foodborne pathogens and spoilage bacteria. To improve flavor of the fermented broth, post-fermentation of the fermented broth was carried out at $4^{\circ}C$ by using yeast isolated from raw material mixture. Total acidity of the post-fermented broth was slightly decreased, but significant increase in the concentration of succinic acid was observed in the post-fermented broth. It was also observed that bitter and disagreeable taste compounds such as phthalates were decreased, and mild acidic and fruity flavor esters and alcohols were increased by the post-fermentation of the fermented broth with yeast.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.663-669
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• 2000

As an attempt to develop new functional beverages, various ingredients including pine needle, P Japonica, C. Militaris, black tea, artemisia, cocoa, and persimmon leave tea, were used to make fermented beverages and their chemical and sensory properties were evaluated. The acidity of beverages produced was the highest in the one with C. Militaris, and the lowest in the ones with persimmon leave tea and pine needle. The pH of P Japonica beverage, 2.54, was the lowest among all. The sugar content was the highest in the one of C. Militaris and the lowest in cocoa-used one. In sensory evaluation, the fermented beverages prepared with persimmon leave tea, pine needle, and artemisia were significantly more preferable in acceptability than the others (p<.001). For purchase intention, the beverage prepared with persimmon leave tea got the highest score followed by the ones with pine needle and artemisia, and the scores of those three beverages were significantly higher than the others (p<.001). Hunter color test showed that fermented beverage added Black tea was the lowest in lightness, but the highest in redness and yet-lowness(p<.001). The beverages with high scores in sweet odor, sweet taste, and purchase intention were more favored in the sensory evaluation looking at the correlation among the sensory properties. And the lightness in color had a positive correlation, and the redness and yellowness had negative correlations with appearance quality of the beverages. Chemical properties like pH and acidity were negatively correlated with the acceptability, and the sugar content was positively correlated with sweet odor.

• Food Science and Industry
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• v.49 no.4
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• pp.94-99
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• 2016

Development of synthetic vinegar has been focused on the acidic taste typically caused by acetic acid. Recently, consumer interest in fermented vinegars which contain a variety of valuable nutrients increased growth of the beverage industry. Vinegar beverages made of a variety of foreign fruits such as pineapple, grapefruit, and aloe are being commercialized to meet market needs from female consumers interested in beauty. However, commercialization of traditional fermented vinegars using regional products such as rice has not been successful yet compared to fruit vinegar beverages. Systematic research for development and commercialization of functional value-added traditional vinegars made of regional agricultural products should be performed. In this study, type and manufacturing methods of traditional vinegar were reviewed based on classic literatures.

• KSBB Journal
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• v.26 no.5
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• pp.374-380
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• 2011

Earlier in Korea Kimchi was made in every family and every province has own taste and specialties. These days almost of the Kimchis are manufactured. We collected variable Kimchis, which were made for private use and isolated microorganisms. Some interesting micobial cells were identified and studied for its application as food and drinks. One of them was identified as Lactobacillus sakei KJ123. This strain is known as producing interesting aromatic components during Sakei fermentation like Kimchi in variable conditions. We tried to develop a health beverage with fermentation process. The Cucurbita maxima has been known as a traditional healthy food and variable positive effects on the human body were already reported. In this study we tried to develop a production process for a healthy fermented drink on this substrate with strains originated from Kimchi. Many kinds of lacctobacilli species existed in the fermented food cannot survive in the acidic conditions like human stomach. So we selected resisting strains in this conditions. The survival rate of Lactobacillus sakei cells in the artificial gastric juice and bile acid and other physiological characteristics at the variable conditions have been tested. After fermentation process some sensory tests on the product with panels were tried.

• Food Science and Preservation
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• v.24 no.5
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• pp.714-724
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• 2017

Soju is a Korean traditional distilled alcoholic beverage produced from mashes various crops and Nuruk which is cultured with wild microorganisms. This study was conducted to investigate rice-Soju brewing characteristics of yeasts isolated from Korean traditional Nuruk. The general components of rice (Hanarumbyeo) raw materials were 14.7 g of water, 6.8 g of crude protein, 0.9 g of crude lipid, 0.4 g of crude ash, and 76.5 g of carbohydrate in 100 g. Saccharifying and proteolytic activities in Hanarumbyeo ipguk (solid-state culture of Aspergillus luchuensis) were also determined. The alcohol content of the fermented wash from isolates was 15.37-16.58% (v/v), which is 16.7-36.0% higher than that of industrial yeasts (12.33-13.19%). Reducing sugar contents were 2.04-3.92 and 7.92-8.78 g/100 mL in the isolates and industrial yeasts, respectively. The isolated yeasts showed 25.2-52.7% higher yield of distillates (41% alcohol) compared to industrial yeasts. Forty-one components were detected in the rice distillated Soju (25% alcohol) and principal component analysis revealed differences between the isolated and industrial yeasts with respect to the contents of i-BuOH, isobutanal diethyl acetal, ethyl caprate, and tetradecanoic acid.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.378-383
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• 2007

To study the characteristics and processing of Kochujang which is rapidly fermented by commercial enzymes, three kinds of Kochujang(KP-FA, KP-FN, and KP-BN) using commercial proteases and one Kochujang(KM) using Meju were prepared and their qualities investigated. There were only small differences in pH and acidity between each Kochujang. The moisture contents were high tendency in the three kinds of Kochujangs using the commercial proteases at 20 days of fermentation. Reducing sugars had a tendency to decrease during the fermentation in the Kochujangs using the proteases. During the first half of fermentation, the Kochujangs made with proteases showed higher amino nitrogen contents than the Kochujang(KM) made using Meju. Acidic protease activity was high in KP-FA at 20 days of fermentation and neutral protease activity was high in KP-FN and KP-BN at the beginning of fermentation. The Kochujangs made using the proteases, through 20 days of fermentation, obtained high preference in the sensory evaluation for color, texture, and overall acceptability. However, the hot taste was stronger in these Kochujangs during the fermentation.

• Journal of Dairy Science and Biotechnology
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• v.36 no.3
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• pp.178-185
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• 2018

Kefir, which originates in the Caucasian mountains, is a cultured milk beverage produced by a combination of acidic and alcoholic fermentation. Kefir products are commonly used as food vehicles to deliver health-promoting materials including kefran and lactic acid bacteria to consumers. The aim of this study was to develop a freeze-dried starter culture without yeast and assess the suitability of kefir-like dairy products for the growth of lactic acid bacteria and the acidification of milk. Pasteurized whole milk (SNF 8.5%) stored at $25^{\circ}C$ was aseptically inoculated with starter cultures (0.002% w/v); it was kept at $25^{\circ}C$ until the pH attained a value of 4.6. Ten grams of the kefir-like product sample was diluted with 90 mL of 0.15% peptone water diluent in a milk dilution bottle, followed by uniform mixing for 1 min. Viable cells of Lactobacillus species were enumerated on modified-MRS agar (pH 5.2), with incubation at $37^{\circ}C$ for 48 h. Viable cells of Lactococcus species were enumerated on M17-lactose agar, with incubation at $32^{\circ}C$ for 48 h. The pH attained a value of 4.6 after fermentation for 9 h 30 min (Starter 1), 9 h 45 min (Starter 2), and 12 h (Starter 3). The viable cell count of Lactobacillus sp. and Lactococcus sp. was initially $10^5{\sim}10^6CFU/g$; it increased significantly to $10^9CFU/g$ after 12 h of incubation. During the storage of the kefir-like products at $4^{\circ}C$ for 1 4 days, the total viable cell numbers were unchanged, but the pH decreased slightly. The consistency of the kefir products increased gradually during the storage. The organoleptic properties of the kefir products fermented using the new starter culture are more desirable than those of commercial kefir. These results suggest that the newly developed starter culture without yeast could be suitable for kefir fermentation.