• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.70-76
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• 2013

The aim of this research was to analyze makgeolli with nineteen kinds of rice and koji. Among 19 rice, 18 rice were domestic products and one rice was an import. For the properties of koji made with 19 kinds of rice, the acidity was over 5.0 and the saccharogenic power was more than 60SP. Makgeolli brewed with 19 kinds of rice and the koji of each rice were analyzed for alcohol contents, pH, total acidity and solid contents during fermentation. After fermentation, raw liquor's alcohol degree was set 6.0%, the pH ranged 3.47-3.76, the total acidity 0.27-0.44%, the solid contents and the reducing sugar were $2.7-4.6^{\circ}$Bx and 2.49-6.01 mg/mL. Organic acid was detected 5 kinds (oxalic, malic, lactic, acetic, succinic acid) and free sugars were found such as glucose, maltose and fructose. Hwayoung, Hopum and Sura were higher than the residue in 15 kinds of rice in the preference test.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.92-97
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• 2018

The antioxidant activities and quality characteristics of Matcha (powdered green tea) spreads containing coconut milk were evaluated. Matcha spreads containing coconut milk was prepared with different amounts (0, 4, 8, 12, and 16 g) of Matcha, and indicated as S1, S2, S3, S4 and S5, respectively. The moisture content, viscosity, color, pH and sugar content were influenced by the concentration of Matcha. Total phenolic content and total flavonoid content of Matcha were found to be 226 mg GAE/g and 809.42 mg QE/g respectively. Also, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and reducing power of Matcha was found to be $5.76{\mu}g/mL$ ($IC_{50}$) and 2.26 O.D., respectively. The antioxidant activities of the Matcha spreads containing coconut milk increased with increasing concentration of Matcha. Sensory evaluation indicated that S3 (8 g) was the most preferred in terms of color, taste, texture, and overall acceptance. Based on these results, it is suggested that S3 (8 g) was appropriate for achieving good quality coconut milk based spread containing Matcha.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.263-269
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• 2005

Citrus juice, a concentrate manufactured by the Jeju Provincial Corporation, was converted into vinegar orderly by alcohol and acetate fermentation. The juice with 6 folds dilution by distilled water was used as the sole nutrient source through out experiments. Diluted juice contained $12.96^{\circ}Brix$ of total sugar, $0.632\%$ of total acid and $20.23{\mu}g/m{\ell}$ of hesperidin. Naringin was not detected from the juice. Citrus wine having $5.6\~6.3\%$ alcohol was produced from diluted juice by 3 days of fermentation at $28^{\circ}C$. A kind of malomelo yeast CMY-28 was used for wine fermentation. The wine was succeedingly fermented for 8 days at $30^{\circ}C$ after inoculation of seed vinegar which contained active cells of acid producing bacteria CV1. Inoculum size of seed vinegar was controlled to $10\%$(v/v) of citrus wine. The wine converted into vinegar by the fermentation. Citrus vinegar, the final product of fermentation, was colored with very thin radish-yellow and transparent. It's acidity ranged between $5.8\~6.2\%$ as acetic acid. The vinegar got the best score by sensory test among several natural fruit vinegars. It was clear from the results that citrus vinegar in high quality could be produced from concentrated citrus juice, however fermentation conditions should be improved to reduce the amount of reducing alcohol.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.600-608
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• 2006

The purpose of this study was to investigate the physicochemical characteristics of Cabbage Kimchi with different kinds of jeot-kal. The Cabbage Kimchis were stored at 4${\pm}$1$^{\circ}C$ for 49 days. The pH of all samples of Cabbage Kimchis decreased during fermentation. The total acidity of Cabbage Kimchis increased gradually during fermentation and that of Cabbage Kimchis with different kinds of jeot-kal was higher than that of control. Redox potentials and reducing sugar content decreased gradually during fermentation. Total vitamin C content of Cabbage Kimchis with different kinds of jeot-kal was much higher than that of control. In color measurement, the lightness value decreased gradually, whereas the redness and yellowness values increased gradually during fermentation. The content of hot water soluble pectin (HWSP) decreased as the fermentation proceeded, but that of hydrochloric acid soluble pectin (HCISP) and sodium hexametaphosphate soluble pectin (NaSP) increased.

• Korean journal of food and cookery science
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• v.13 no.3
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• pp.286-292
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• 1997

The purpose of this study was to investigate the effect of citron (Citrus junos) on Dongchimi (watery radish kimchi) fermentation. Dongchimi with various levels (0, 1, 2, 4, 6％) of citron was fermented at 10$^{\circ}C$ for 36 days. The pH of Dongchimi decreased slowly in all samples during fermentation, however, it was slightly lower in citron-added Dongchimi. Total acidity and turbidity of Dongchimi increased gradually during formentation, in which the level of increase was greater as the ％ of added citron increased. However, the total acidity and turbidity of Dongchimt without citron increased dramatically on 36$\^{th}$/ day of fermentation, and reached the values similar to those of Dongchimi with 6% citron. Reducing sugar content increased gradually up to 15∼23 days of fermentation and decreased rapidly for the rest of the period. The content of vitamin C was much higher in citron-added Dongchimi, and especially it was 4 times higher than that of without citron at the beginning of fermentation. The number of lactic acid bacteria reached the maximum on 15$\^{th}$/ day in citron-added Dongchimi and on 30$\^{th}$/ day in Dongchimi without citron, and decreased thereafter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1219-1224
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• 2007

In this study, we explored the application of Wasabi addition to baechu kimchi with regard to quality improvement, by reviewing the optimum Wasabi level and its effects on the product physicochemical characteristics during fermentation. The final weight percentages of Wasabi in the baechu kimchi were adjusted to 0, 2, 3, 4, and 5% per weight of baechu, respectively, and the samples were fermented for 35 days at $10^{\circ}C$. Following fermentation, the treatments over 3% Wasabi contained the highest pH and lowest total acidity values. Total vitamin C and reducing sugar content increased initially, up to certain fermentation times depending on the level of Wasabi contents within the treatments over 3% Wasabi, and decreased afterwards. The water soluble pectin content increased as the fermentation period increased; however, it decreased with increasing levels of Wasabi. In conclusion, the optimum levels of added Wasabi in the baechu kimchi were 3% and 5% per weight of baechu, to have a fermentation-retarding effect on the product.

• Food Science and Preservation
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• v.18 no.6
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• pp.891-897
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• 2011

Oak barrel have been used for a long time for the aging of wine. Instead of oak barrel aging, however, roasted oak chips can be directly added in the wine before aging. In this study, Korean oak chips roasted for different time durations were used for the red wine aging, and the properties of wine aged through the addition of the roasted oak chips were characterized. No significant differences were observed in the alcohol, soluble-solid, reducing-sugar and total-acid contents based on the oak chips aging, but the total phenol content increased. The methanol, ethyl acetate, propanol, isobutanol and isoamyl alcohol contents also increased. Especially, the methanol and propanol contents increased as the roasting time was prolonged. Although the hue values were similar to one another, the intensity as well as the lightness, redness, and yellowness values were high in the wine aged with the roasted oak chips. In the sensory evaluation, the wine aged with oak chips roasted for 2 h showed the highest scores in the flavor, taste, and overall preference.

• 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.

• Food Science and Preservation
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• v.19 no.6
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• pp.925-932
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• 2012

This study was performed to improve quality of traditional Yakju and compares quality of Yakju according to different rice cultivars. The pHs of Ilmi Yakju and Hanarum Yakju showed 4.14 and 4.07, respectively and the other Yakju's pHs were ranged from 3.92 to 3.98. The content of total acid of Yakju using Indica rice imported from Thailand was the highest among the samples. The major components of free sugar was glucose and the highest content of total free sugars was found in Indica Yakju. The content of reducing sugars in Yakju using Indica rice was the higher than other samples. The ethanol content of Hanarum Yakju showed higher than those Yakju's and the lowest ethanol content found for the indica Yakju. The volatile compounds from the rice Yakju were identified by GC-MS. Twenty-one volatile compounds were found in rice Yakju. And the major volatile compounds were ethanol, acetic acid, 1-methyl-1-propanol, 2-methyl-butane, 3-methyl-1-butanol, iso-amylalcohol and 1-hexanol from Yakju. As the result of sensory test, higher scores for smell and color were found for the Yakju used Hanarum Yakju. The highest score sweat and acid were found for the Anda rice Yakju in sensory test. The result of sensory evaluation indicated that Hanarum Yakju and Anda Yakju were better than the other samples, and the value of bitterness was no significant in this test.

• Food Science and Preservation
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• v.17 no.5
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• pp.616-624
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• 2010

We compared the physicochemical properties of, and volatile components in various commercial fruit vinegars (made from apples, grapes, and persimmons). Total acidity was highest in grape vinegars. Significant between-sample differences were evident in total and reducing sugar contents. Brownness, turbidity, and overall color difference (the ${\Delta}E$ value) were highest in persimmon vinegars. Free sugars were composed mainly of fructose, glucose, sucrose, and maltose. Major organic acids were present in the (descending abundance) order acetic acid, oxalic acid, citric acid, malic acid, and succinic acid, among-samples difference were negligible. Nine-essential free amino acids were detected in nine types of grape and persimmon vinegars, and in six varieties of apple vinegar. Among 17 types of volatile compounds identified in apple vinegars, 12 in grape vinegars, and 33 in persimmon vinegars, the main volatile components were acetic acid, ethyl acetate, isoamyl acetate, isovaleric acid, isoamyl alcohol, propanoic acid and phenethyl acetate. Volatile chemicals in commercial fruit vinegars were effectively analyzed using a SAW e-nose.