• Journal of Microbiology and Biotechnology
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• v.3 no.2
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• pp.129-133
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• 1993

The effect of different compositions of organic acids on the flavor profile of 10% sugar solution was investigated by the response surface methodology, and the results were used to evaluate the flavor characteristics of lactic acid fermented cereal beverages. A mixture of extruded rice flour (10%) and soymilk (7.8% dry matter) was fermented with Leuconostoc mesenteroides (Sikhae). Depending on the substrate pretreatments, for example, the malt or amylase digestion and the proteolytic enzyme hydrolysis, the sugar and organic acid composition of the product varied. The organic acid composition of the fermented beverages was in the ranges of 0.44-0.55% lactic acid, 0.05-0.09% acetic acid and 0.07-0.09% citric acid, while that of commercial apple juice was 1.59% malic acid and 0.49% acetic acid. The flavor profiles of fermented beverages added with 10% sucrose were compared to those of apple juice and a model mixture containing 0.48% citric acid, 0.39% lactic acid and 0.12% acetic acid in 10% sugar solution. The QDA diagram of fermented beverages approached to that of apple juice, when the substrate was digested by amylase but not by protease.

• The Korean Journal of Community Living Science
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• v.21 no.4
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• pp.481-488
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• 2010

The objective of this study was the development of the preparation method of fermented turnip juice. The yields and soluble solids of fermented turnip juice were 41.2, 52.8, 56.4 and 57.4%, and 34.3, 42.4, 48.6 and 54.7 $^{\circ}Brix$ with 40, 60, 80 and 100% addition rate of turnip quantity, respectively. The major organic acids in turnip juice were succinic acid, isobutyric acid and fumaric acid, and these organic acids were decreased after fermentation. On the other hand, lactic acid, formic acid, acetic acid, propionic acid and butyric acid were produced during the fermentation. Soluble solid and pH value in fermented turnip decreased by time-dependently. Free radical scavenging activity was increased by fermentation of turnips and nitrate scavenging effects were the highest in pH 3 and increased with adding Omija or Japanese apricot. The best preparation method of fermented turnip juice was fermentation at $24^{\circ}C$ 12-15 days after adding 40% of sucrose to total quantity. As adding Omija, organic acid contents were increased and sensory evaluation was improved in fermented turnip juice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.567-572
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• 2010

This study is to develop vinegar with germinated brown rice and red pepper (Capsicum annuum) for effective use of the rice and red pepper. The vinegar was prepared using the wine fermented from the germinated brown rice supplemented with 10~50% red pepper. Acetic acid fermentation was carried out with 6% (w/v) initial ethanol concentration, at $30^{\circ}C$. pH values decreased from 4.27~4.41 to 3.20~3.59 during acetic acid fermentation. The initial total acidity (0.29~0.41%) changed to 3.68~4.51% after fermentation. Hunter's a (redness) and b (yellowness) values also increased as the addition of red pepper increased to 30%. Major volatile compounds consisted of ethyl acetate, 3-methyl-1-butanol, acetaldehyde, ethanol and acetic acid. Capsaicin content (0.17~0.26 mg%) at the initial changed to 0.16~0.29 mg% at the final of the fermentation. Antioxidant activity decreased from 48.1~79.1% to 36.6~64.9% by the fermentation. The germinated brown rice vinegar added with red pepper had higher acceptance scores than that of the control without red pepper.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1727-1734
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• 2005

The fermentation characteristics and mono- and di-saccharides compositions during the early stage of ensiling were studied with a temperate grass, Italian ryegrass (Lolium multiflorum Lam.) and a tropical grass, guineagrass (Panicum maximum Jacq.). The laboratory silos were kept in the room set at 25$^{\circ}C$, and then were opened on 0.5, 1, 2, 3, 5 and 7 days (14 days in Italian ryegrass) after ensiling, respectively. The Italian ryegrass silage showed a fast and large pH decrease caused by a fast and large production of lactic acid during the first 5 days of ensiling and succeeded to achieve lactic acid type fermentation; high lactic acid/acetic acid and lactic acid content at the end of ensiling (14 days), low values of pH (3.74), acetic acid, ethanol and ammonia-N/total nitrogen, none or only small amounts of Butyric acid, valeric acid and propionic acid. The guineagrass silage showed a slow decrease in pH and a slow increase in lactic acid content during the full ensiling period, causing a high final pH value, low contents of lactic acid, acetic acid, total volatile fatty acids and total organic acids. In Italian ryegrass silage, mono- and di-saccharides compositions decreased largely within the initial 0.5 day (12 h) of ensiling. Sucrose disappeared rapidly within the initial 0.5 day of ensiling, but fructose and glucose contents showed an initial rise by the activity of enzymes in plant tissues, and then decreased gradually. On the other hand, the contents of monoand di-saccharides in guineagrass showed the largest decreases due mainly to plant respiration within the initial 0.5 day of ensiling, and no initial rises in fructose and glucose contents during the early stage of ensiling because of the absence of fructans which are hydrolyzed into fructose and glucose in temperate grasses. In both silages, the rate of reduction in mono- and di-saccharides compositions within the initial 5 days of ensiling was ranked in the order of glucose>fructose>sucrose, suggesting that glucose and fructose might be more favorably utilized than sucrose by microorganisms and glucose is the first fermentation substrate. It was concluded that the silage made from Italian ryegrass with high moisture content had a good fermentation quality owing to the dominance of lactic acid bacteria and active lactic acid fermentation during the initial stage of ensiling. These results can be explained by rapid plant sap liberation and the high activity of plant enzyme hydrolyzed fructans into fructose and glucose within the initial 2 days of ensiling, which stimulate the homofermentative lactic acid bacteria growth. In ensiling a temperate grass, the physical characteristics may ensure the rapid onset of fermentation phase, which results from the smaller losses of water-soluble carbohydrates during the initial stage of ensiling and providing sufficient water-soluble carbohydrates for lactic acid bacteria. The silage made from guineagrass with intermediate dry matter and high initial mono- and di-saccharides content was stable silage. This could be explained by the higher incorporation of air during the very early stage of ensiling and the restriction of cell breakdown and juice release due to the properties of a tropical grass with coarse porosity and stemmy structures. These physical characteristics delayed the onset of lactic acid bacteria fermentation phase by extending the phases of respiration and aerobic microorganisms activity, causing the higher loss of water-soluble carbohydrates and the shortage of lactic acid bacteria fermentation substrates.

• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.518-522
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• 1999

The garlic vinegar brewed with 5% ethanol solution added 10% crushed garlic was fermented by Acetobactor aceti 3281 at 3$0^{\circ}C$ for 26days. Pumpkin wine vinegar was made from acetic acid fermentation of pumpkin wine at 35$^{\circ}C$ for 26 days. Pumpkin wine vinegar was made from acetic acid fermentation of pumpkin wine at 35$^{\circ}C$ for 26days. The garlic vineger and pumkin wine vinegar contained 0.04mg/ml and 1.53mg/ml of total sugar 0.122/mg/ml and 0.406mg/ml of reducing sugar and 0.06 and 0.02% of ethanol. Specific gravity of garlic vinegar and pumkin wine vinegar was 8.53 and 8.48CFU/ml respectively. pH of garlic vinegar an pumkin vinegar was 3.06 and 3.20 respectively. Acidity of garlic vinegar and pumkin wine vinegar was 4.98 and 5.02 respectively. Sensory evaluation garlic of vinegar and pumkin wine vinegar was 2.7 and 3.9 respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.563-570
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• 1997

Volatile flavor components in the mash of takjus prepared by using different nuruks such as Mucor racemosus nuruk, Rhizopus japonicus nuruk, Aspergillus oryzae nuruk, Aspergillus kawachii nuruk and nuruk (Korean-style bran koji), were identified by using GC and GC-MS. Twenty alcohols, 26 esters, 10 acids, 10 aldehydes and 6 others were found in the mash of takju after 16 days of fermentation. Takju by Aspergillus oryzae nuruk had the most various components of volatile flavor. Fifty-four flavor components including ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 1-hexanol, 2,3-butadienol (D,L), benzeneethanol, acetic acid ethyl ester, succinic acid diethyl ester, butanoic acid monoethyl ester, acetic acid and benzene acetic acid 4-acetyloxy-3-methyl ethyl ester were usually detected in all the treatments. The relative peak area of volatile components was as follows: alcohol $(71.28{\sim}90.23%)$, ester $(0.66{\sim}9.05%)$, acid $(0.2{\sim}0.6%)$ and aldehyde $(0.02{\sim}0.09%)$. Specially, 1-pentanol and hexanoic acid ethyl ester were high in takju made of nuruk (Korean-style bran koji). 1-Hexanol, 1-dodecanol, acetic acid and 1,2-benzene-dicarboxylic acid diprophenyl ester were high in takju made of Mucor racemosus nuruk. 4-Acetyloxy, 3-methyl benzeneacetic acid phenyl ester, 2-methyl-1-propanol, 3-methyl-1-butanol, succinic acid diethylester, butanoic acid monoethyl ester and butanoic acid were higher content in takju by Rhizopus japonicus nuruk. Acetic acid ethyl ester, pentanoic acid and 3-methyl butanoic acid were high in takju that was made of Aspergillus oryzae nuruk. 1-Butanol was high in takju by Aspergillus kawachii nuruk.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.665-674
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• 2019

Objective: In tropical regions, as in temperate regions where seasonality of forage production occurs, well-preserved forage is necessary for animal production during periods of forage shortage. However, the unique climate conditions (hot and humid) and forage characteristics (high moisture content and low soluble carbohydrate) in the tropics make forage preservation more difficult. The current study used natural ensiling of tropical forage as a model to evaluate silage characteristics under different temperatures ($28^{\circ}C$ and $40^{\circ}C$). Methods: Four tropical forages (king grass, paspalum, white popinac, and stylo) were ensiled under different temperatures ($28^{\circ}C$ and $40^{\circ}C$). After ensiling for 30 and 60 days, samples were collected to examine the fermentation quality, chemical composition and microbial community. Results: High concentrations of acetic acid (ranging from 7.8 to 38.5 g/kg dry matter [DM]) were detected in silages of king grass, paspalum and stylo with relatively low DM (ranging from 23.9% to 30.8% fresh material [FM]) content, acetic acid production was promoted with increased temperature and prolonged ensiling. Small concentrations of organic acid (ranging from 0.3 to 3.1 g/kg DM) were detected in silage of white popinac with high DM content (50.8% FM). The microbial diversity analysis indicated that Cyanobacteria originally dominated the bacterial community for these four tropical forages and was replaced by Lactobacillus and Enterobacter after ensiling. Conclusion: The results suggested that forage silages under tropical climate conditions showed enhanced acetate fermentation, while high DM materials showed limited fermentation. Lactobacillus and Enterobacter were the most probable genera responsible for tropical silage fermentation.

• The Korean Journal of Community Living Science
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• v.17 no.3
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• pp.123-131
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• 2006

To compare the quality characteristics, chunggugjang was prepared with Bacillus subtilis NRLSI IV on the different inoculum levels$(10^2,\;10^4,\;10^6,\;and\;10^8 CFU/ml)$ and fermentation times(0, 12, 24, 36, and 48 hours). Although significant change in total nitrogen content was not found, the content of amino type, soluble and ammonia type nitrogen was generally increased according to the increase in fermentation time. Decomposition rate of nitrogen was also increased by fermentation time and nitrogen solubility was the highest value(62-75.9%) at 48 hour fermentation. In results of color changes, it was found that L and a value were decreased but there was no significant changes in b value as fermentation time was increased. In chunggugjang made with long fermentation time, hardness was decreased and relative viscosity of viscous substance was gradually decreased after little increase at initial fermentation time. The effect of inoculum level on hardness and relative viscosity were similar to that of fermentation time, i.e. the decrease of these at high inoculum level. In activity of V-GTP, 36 hour incubation could produce the highest value whereas no effect of inoculum level was found during fermentation except at 48 hour. In chunggugjang made with $10^2CFU/mL$ of Bacillus subtilis NRLSI IV, the content of glucose, sucrose, raffinose and stachyose was dramatically decreased at initial fermentation time and that of phytic acid, oxalic acid, citric acid, tartaric acid and malic acid was also decreased during fermentation, although the increase in acetic acid was found.

• Applied Biological Chemistry
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• v.4
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• pp.33-42
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• 1963

1. Two fermentation methods have been compared for the production of Takju (Korean native Sake). One method (S1) uses 'Nuruk' (Korean mold wheat) and the other method (S2) uses 'Nuruk' and mold rice. The chemical analysis of source material, also, have been made in order the check the quantitative changes during the fermentation. The results are summarized below: a. The rate of fermentation was slower for the S2 method than for the S1 method. However, the residual sugar in the S2 method was smaller and the amount of alcohol produced the same as with the S1 method. This was true in spite of the fact that the total initial sugar content for the S2 method was 10 percent below that of S1. b. With both the S1 and S2 methods, 80 percent of the total alcohol production was obtained with in 3 to 4 days. c. The pH value of the base material at the beginning of fermentation was markedly different between the two methods I.e.6.0 to 6.2 for S1 and 4.8 to 5.2 for S2. However, after one or two day the pH of both materials was about the same 4.0 to 4.2 and remained at this value unit the fermentation was complete. 2. Organic acids and Sugars in the source materials have been detected by the paper partition chromatography(p.p.c.) method and the followings are obtained. a. Important Organic acids are Fumalic, malic Succinic, Citric, Acetic aicds in polished rice and Fumalic, Succinic, Acetic, Citric, Malic and Oxalic acids 'Nuruk'. The same kinds of acids as in the rice are found in mold rice, However, amount of Citrice acid is markedly increased in mold rice. b. The important Sugar, Glucose, Fructose and Raffinose in polished rice, Gulcose, Fructo, se, Xylose and one which supposed to be Kojibjose in 'Nuruk'. Glucose and those supposed to be Isomaltose, Kojibiose and Sakebiose and found in rice mold, however, no Sucrose, which was exist in polished rice, was found. 3. The important Organic acids found in fermenting mash using the p.p.c. method were Lactic, Succinic and Acetic. Citric acid identified early in the fermentation, S2 method. remained throughout. However, with the S1 method Cirtic acid was detected only during the late stage of fermentation. Sugars not found in the original materials were two which supposed to be Isomaltotriose and Pentose. Maltose found at the beginning of the fermentation disappeared within one day, Isomaltose was detected throughout the period of fermentation. 4. The Somogyi method which was employed to determine the quantitative changes of sugars in the orginal meterial and mach, showed that polished rice containes in order and in largest amounts Sucrose, Glucose, Raffinose and Fructose. 'Nuruk' contained almost equal quantities of Glucose and Fructose. However, the Glucose content of the mold rice exceeded that originally in the polished rice by 25 or 30 times. Only a small quantity of free sugars was found in the mash at the end of the fermentation.

• Food Science and Preservation
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• v.19 no.4
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• pp.594-603
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• 2012

This study developed a high-utility type of vinegar from Rubus coreanus by optimizing its fermentation conditions. In the alcohol fermentation process, the optimal conditions for the maximization of the alcohol contents were an initial sugar concentration of 15 $^{\circ}Brix$, a temperature of $30^{\circ}C$ and 4 days. The optimal conditions for the acetic acid fermentation were 9 days of fermentation at $30^{\circ}C$ and 200 rpm, with 6% alcohol and 2% initial acidity. The sucrose, fructose, and glucose contents were 952.90, 491.01, and 386.62 mg%, respectively. The free organic acids were acetic, malic, succinic, malonic, oxalic, and lactic acids. The total free amino acid content was 104.33 ${\mu}g/mL$, with alanine, glutamic acid, ${\gamma}$-amino-N-butyric acid, and o-phospho-ethanolamine as the major amino acids. The K, Na, and Mg contents were 1,686.10, 172.50, and 69.33 ppm, respectively. The total phenolic and anthocyanin contents were 25.19 and 80.71 mg/100 mL, respectively. The DPPH- and $ABTS^{.+}$ radical scavenging activities were approximately 65 and 94%, respectively. Moreover, the vinegar's ${\beta}$-carotene bleaching activity and reducing power showed that it had strong anti-oxidant properties. These results show that Rubus coreanus vinegar has anti-oxidant properties and may be used as functional food.