• Food Science and Preservation
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• v.5 no.4
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• pp.374-379
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• 1998

A vinegar was prepared from uncleaned rice by two step fermentation, alcohol fermentation followed by acetic acid fermentation. The contents of alcohol reached to 10.8% during the alcohol fermentation of uncleaned rice with nuruk, and acidity reached to 5.78% during the acetic acid fermentation. Acidity and pH of vinegar of two step fermentation were higher than those of commercial vinegars. 'L' value(Light) of the vinegar was lower, 'a' and 'b' value were higher than those of commercial vinegars. The contents of acetic acid, malic acid, citirc acid and tartaric acid were hish in organic acid of vinegars. The content of each ofganic acid in vinegars was remarkably different. The content of free amino acids was 2199.7${\mu}\ell$/ml in the vinegar produced by two step fermentation which is higher than that of others.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.365-374
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• 2016

This study was carried out to investigate the effect of vinegar on pH, total bacterial count, texture and color of rice with vinegar before and after storage at $4^{\circ}C$ and $25^{\circ}C$. This results obtained were summarized as follows : The pH value and total bacterial counts were not significant changed under different storage conditions with sushi vinegar, but control without sushi vinegar was increased the number of bacteria from storage 1 days. and When rice with vinegar was stored at low temperature ($4^{\circ}C$), the tendency of textural changes such as hardness, springiness, cohesiveness, chewiness, brittleness and adhesiveness was almost the same as those of $25^{\circ}C$. However, the rate of change was much higher in rice with vinegar when stored at $4^{\circ}C$ than at $25^{\circ}C$. and The Hunter's color parameters such as L, a, and b, of rice with vinegar were not changed much during storage at both $25^{\circ}C$. However, L value was slightly increased during storage, but a value was increased negatively without changing b value of rice with vinegar during storage at $4^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.202-206
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• 2012

In order to prepare rice vinegar, $takju$ fermentation was performed, using two different compositions; cooked rice supplemented with $Rosa$ $rugosa$ Thunb. (CR-R) and uncooked rice supplemented with $Rosa$ $rugosa$ Thunb. (UR-R). After ethanol fermentation, ethanol contents of $takju$ were adjusted to 6.0%, and then acetic acid fermentation was carried out using $Acetobacter$ $aceti$ at $30^{\circ}C$ with 200 rpm for 9 days. Supplementations of 1% acetic acid to $takju$ prior to acetic acid fermentation were a critical step in achieving a successful fermentation; final organic acid contents increased in a dose dependent manner. A higher content of organic acids, 1.6-6.9%, was found in UR-R vinegar. The level of free amino acid and GABA in UR-R vinegar was higher than that of CR-R vinegar, with glutamic acid and arginine, as the major amino acids. This finding demonstrates that heating process of rice prior to ethanol fermentation affects the quality of vinegar significantly.

• Korean journal of food and cookery science
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• v.9 no.1
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• pp.25-29
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• 1993

This study was attempted to enhance taste and quality value of cooked rice by adding fat, vinegar, cellulose in cooking water. Cooked rice with five different levels of material in cooking water (100% water A: 10% vinegar B: 10% fat C: 10% fat and 10% vinegar D: 10% fat, 10% vinegar and 10% celloulose) was tested for rheology, fine structural changes, sensory evaluation, in vitro digestion. 1) Cooked rice by adding 10% fat rate was higher than A, B, D, E samples for softness, Jelly and increased in vitro digestion. 2) sensory evaluation conducted by tweenty university students a panelists showed that B, D sample were low value in flavour, texture and taste, but higher than A sample for softness, Jelly and in Vitro digestion. 3) E sample (l0% fat, 10%s vinegar, 10% cellulose) was more significant for taste, texture, and digestion than A sample. From these results, it was concluded that rice cooked with 10% of fat in cooking water was quite acceptable, in terms of practical food value consisting of palatability rheology and digestibility.

• Food Science and Preservation
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• v.11 no.1
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• pp.117-121
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• 2004

We investigated antimicrobial effects of commercial vinegar on the harmful food-born organisms. As a result, antimicrobial effects of brown rice vinegar showed stronger than persimmon and artificial vinegar. In 10${\mu}$L/mL concentration of brown rice vinegar was completely inhibited about 5 strains except for V. parahaemolyticus, it was inhibited 15${\mu}$L/mL concentration. Therefore vinegars were effective for inhibition acitivity against food borne organisms. S. aureus and E. coli treated with 25${\mu}$L/mL concentratioin brown rice vinegar was observed by scanning electron micrographs(SEM). The cells were expanede and a part of cell wall was completely destructed by brown rice vinegar.

• Journal of the Korean Society of Food Culture
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• v.14 no.1
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• pp.17-20
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• 1999

Three kinds of traditional Andong vinegars, manufactured from Songwhaju which was a traditional rice alcoholic beverage in Andong province, were investigated on the physicochemical characteristics compared with commercial rice vinegar speciality and on the factors affecting their flavor components. Traditional Andong vinegars had a low level of total acids$(3.1{\sim}3.6%)$ and more soluble solids than rice vinegar speciality. Lactic acid contents were also high and it came from lactic acid fermentation in the early stage of the vinegar manufacturing process. Other organic acids such as malic, citric and succinic acid were also detected. Free amino acid analysis showed that alanine, arginine and leucine contents, which were known as a main characteristics of rice vinegar, were especially high. In addition, a considerable amounts of glutamic acid and aspartic acid which were known as a mild effectors of acidic taste in rice vinegar products were detected.

• Food Science and Preservation
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• v.16 no.6
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• pp.893-899
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• 2009

We compared the physicochemical properties of commercial brown rice vinegar fermented with and without ethanol. The pH and total acidity did not significantly differ between the two types of vinegar. Sugar content, reducing sugar content, and free sugar concentration were higher in commercial brown rice vinegar fermented with ethanol, whereas browning, turbidity, and overall color darkness were higher in vinegar fermented without ethanol. The ratio of acetic acid to total organic acids was 0.94 - 0.96 and 0.97 - 1.00 in commercial brown rice vinegar fermented with or without ethanol, respectively. A higher content of total amino acids, 93.07 - 509.48 ppm, was found in vinegar fermented without ethanol. Fermentation conditions affected the physicochemical properties of brown rice vinegar, as shown by significantly higher $\gamma$-aminobutyric acid (GABA) content in brown rice vinegar fermented without versus with ethanol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.149-154
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• 2016

Cosmeceutical potentials of unpolished rice vinegars containing different amounts of Monascus-fermented soybean powder (soy-koji) were investigated. Four different vinegar types were prepared using 0, 10, 30, and 50% soy-koji addition. Soy-koji vinegar showed stronger cosmeceutical properties, in terms of tyrosinase and elastase inhibitory activities as well as antioxidant capacities, than unpolished rice vinegars (P<0.05). Bioactive effects of soy koji vinegar increased with increasing concentrations of total phenolics and isoflavone aglycones (P<0.05). Results indicate that unpolished rice vinegar supplemented with soy-koji can be an efficient strategy to improve bioactivities in vinegar with associated enhancement of cosmeceutical functionality.

• Mycobiology
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• v.47 no.2
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• pp.250-255
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• 2019

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0-3.3 and 3.0-8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ${\sim}1{\times}2{\mu}m$ in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

• Food Science and Preservation
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• v.10 no.4
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• pp.565-568
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• 2003

The antibacterial activity for S. mutans by using 5 kinds of vinegar was researched. As a result it was the highest at persimmon vinegar and then grape, apple, high calcium brown rice, brown rice vinegar in order. The antibacterial effect was shown at 1.5% of persimmon vinegar concentration and the growth was fully repressed at 4% of concentration. As an observation result with a transmission electron microscope(TEM), the growth was obstructed by destroying the cell wall and the cytoplasmic membrane. As a research result of the total phenol contents for each vinegar, the persimmon vinegar was the highest as 237.49 mg% and the antibacterial activity was increased when the total phenol contents were high.