• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.548-554
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• 2016

Since some strains of kimchi lactobacilli can curdle milk, they can be used for making yogurt. However, the best Lactobacillus plantarum strains for curdling milk for yogurt are still unknown. In this study, we determined the best L. plantarum strains for curdling milk, and the physicochemical properties of yogurts made using different L. plantarum strains were examined. Three strains of L. plantarum useful for curdling milk were identified (YD2, YD9, YD12). The number of lactobacilli was lower in yogurts made with L. plantarum than in those made with control, and among the L. plantarum strains tested, YD12 had the highest bacterial counts. However, the microbial count reached $6.3{\times}10^8CFU/mL$ after 24-h fermentation in all yogurts. The pH of the yogurts decreased after 12-h fermentation, while the acidity increased. The low pH and high acidity decreased the viscosity in all the three types of yogurts, because the acids disturbed gel formation due to protein denaturation. Sensory evaluation revealed that the YD12 group showed a high percentage of completion similar to the control group. YD2 and YD9 showed a high sourness value and low sweetness value, whereas YD12 yielded optimal values for all the organoleptic characteristics. Therefore, YD12 would be a high quality bacterial strain for use as a yogurt starter culture.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.123-128
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• 1991

Addition of two different salt mixtures of sodium phosphates, Ca-EDTA, $NaNO_2$ and sodium citrate were investigated for their effects on relative viscosity, textrue, sensory properties of kimchi and solids contents of kimchi and kimchi liquid during fermentation at $4{\sim}3.5^{\circ}C$. The salt mixtures were added into half fermented kimchi with the concentration range of $0.001{\sim}0.01\;M$. The results showed that higher values in viscosity of kimchi liquids were obtained for those fermented at low temperature and with salts mixtures added. The hardness of Chinese cabbage was gernerally increased until pH 4.0 reached and then decreased thereafter for those fermented without salts mixture. However the salts added kimchi showed no decrease and a slightly harder texture measured at the late stage of fermentation. Soluble solids concentration steadly decreased in kimchi liquids for those salts mixture added while those without salts mixture were initially increased followed by slow decrease. Comparison of sensory properties showed that the degree of changes was reduced when salt mixture was added. Higher scores in fresh-sourness and acidic taste, hardness and chewiness in texture and lower moldy odor were obtained when the data was compared for those kimchi having the pH range of $4.0{\sim}4.2$.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.303-314
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• 2011

The purpose of this study was to determine the optimal mixing conditions for two different amounts of added mulberry powder and fresh cream to prepare functional chocolate with added mulberry powder. The experiment was designed according to the central composite response surface design, which showed 10 experimental points, and included two replicates for mulberry powder and fresh cream. The physiochemical, mechanical, and sensory properties of the test were measured, and these values were applied to the mathematical models. The results of the physiochemical and mechanical analyses of each sample, including pH, moisture content, total phenolic content, DPPH free radical scavenging activity, color L, color b, hardness, gumminess, and cohesiveness showed significant differences. The sensory characteristics of the samples tested were significantly different in flavor, texture, sourness, bitterness, and overall acceptability. The optimum formulation calculated by numerical and graphical methods was 25.76 g mulberry powder and 72.21 g fresh cream.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.228-234
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• 2002

In this paper, we proposed a preparation of Jeung- pyun (Korean fermented steamed rice cake with sour taste and spongy texture) using fuzzy theory. Before this preparation was introduced, it thoroughly analyzed the existing data of Jeung-pyun preparation with sensory evaluation and instrumental measurement. It defined a membership auction of Fuzzy set by analyzed three sorts of data on Jeung-pyun. And it established the Fuzzy model using the quantity of materials as input, such as rice, flour, wheat flour and fermentation time, and the sensory test scores as output, such as grain, softness, sourness, chewiness, overall quality, pH value and volume, respectively. We got the results that the Fuzzy model was accord with the conventional method with sensory evaluation. And the validity of this method is shown through the computer simulation of the test data. Therefore, the proposed method by Fuzzy model will apply to make Jeung-pyun without sensory evaluation. This study will contribute to develop standard preparation for korean foods and expert system of preparation using computer system.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.724-731
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• 1990

The fermentation process of Andong Sickhae including optimal composition of the product was investigated. Through sensory evaluation and ingredient analysis of ten samples prepared in the laboratory and the samples collected from Andong region, we found that the ratio of ingredient of the product by weigh are as follow : [glutinous rice(80) : malt(50) : radish(100) : water(500) : ginger(8) : red pepper(4)]. The level of nitrogen compound turned out to be low while that of soluble protein and salt soluble protein was high. The content of total sugar and reducing sugar was found to be considerable high and among the free sugar, maltose was the highest(80%), followed by glucose and maltotriose. Activities of acid protease and saccharogenic amylase were 1.55 unit per milliliter and $12.5D^{40}_{30}^{\circ}$ respectively. Results of sensory evaluation showed that the good Andong Sickhae turned out to have well harmonized taste of flavor, sweetness and sourness while the color looked slightly red.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.80-85
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• 2004

This study was performed to provide basic quality characteristics data of Kimchi by storage containers that will be applied for Kimchi storage container development of new material. In all storage containers, pH was decreased with increased storage days, while acidity was increased with increased storage days, The changes of pH and acidity by storage containers were alumina < stainless < bio < plastic. Salt content was same to all containers. In all storage containers, reducing sugars of Kimchi at first were 22.65${\pm}$0.04$\^$a/ mg/mL. But as these of alumina, stainless, bio and plastic at storage after 31 days were 11.18${\pm}$0.15$\^$a/ mg/mL, 5.39${\pm}$0.02$\^$b/, 3.74${\pm}$0.10$\^$c/, and 3.14${\pm}$0.02$\^$d/ mg/mL, respectively. The hardness, cohesiveness and gumminess of Kimchi by storage containers decreased with increased storage days. And the changes ratio of these were alumina < stainless < bio < plastic. The desirable organoleptic characteristic such as sourness, fresh cabbage taste and firmness were long time maintained at alumina container A significant evidence was detected that the alumina container showed less quality change than that of bio, stainless and plastic containers as storage days increased.

• Food Science and Preservation
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• v.23 no.6
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• pp.788-796
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• 2016

This study presented the change of quality characteristics of Doenjang with various salt concentrations (4, 8, 15, and 20%) during 12 months. The pHs of Doenjang during fermentation were gradually increased for 12 months, whereas the pHs of Doenjang with 4 and 8% salt increased rapidly. Titratable acidity of Doenjang with 4 and 8% salt was high at initial time, while Doenjang with 15 and 20% salt was high at the 9 and 12 months. The amino-type nitrogen content of Doenjang with 4 and 8% salt was increased and ${\alpha}-amylase$ activity of all Doenjang was decreased during whole fermentation period. The protease activity of Doenjang with 4 and 8% salt was higher than Doenjang with 15 and 20% salt until 7 months. Total aerobic bacteria number 8.0~9.1 log CFU/g for 12 months, which was steady during fermentation period. Doenjang with 8% salt showed the highest score in umami taste whereas the lowest score in bitterness, astringency, and sourness tastes between 5 and 12 months. In conclusion, Doenjang with 8% salt was a suitable concentration for low-salt fermented foods.

• Journal of Ginseng Research
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• v.33 no.4
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• pp.343-348
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• 2009

This study was conducted to produce a new red ginseng by steaming ginseng using a new pre-treatment method, so as to develop ginseng products with improved flavor and thereby expand ginseng's consumer base. The color parameters (Hunter value), free sugar contents, and ginsenoside contents of the powder from the dried red ginseng, and the sensory test of the semi-dried red ginseng and the decoction from the dried red ginseng, were measured to investigate the effect of acid (ascorbic acid or citric acid) impregnation pre-treatment on red ginseng. The powder from the acid-pretreated red ginseng became lighter and more yellow than the red ginseng that was not pre-treated, but the redness (avalue) of the powder from the acid-pre-treated red ginseng increased. The ginsenoside contents of $Rg_2+Rh_1$ and $Rg_3$ increased with the acid treatment. There was a significant difference in the color and sweetness of the semi-dried acidtreated and non-treated red ginsengs in the sensory test. As the results of the sensory test were expressed in the hedonic scale, however, there were significant differences in the degrees of bitterness, astringency, sourness, odor, and color of the red ginseng decollation. Especially, the acid-treated red ginseng extract tasted less bitter, which shows the potential of new red ginseng products with improved ginseng flavor.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.663-670
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• 1997

Four kinds of commercial vinegars were investigated to compare physicochemical properties (pH, acidity, color, tannin and metal content), minor components (free sugar, free amino and organic acid), and their organoleptic tastes. The ratio of nonvolatile organic acid to the total organic acid was decreased in the order of brewed, cider, brown rice, and persimmon vinegar. Especially malic acid content was appeared to be highly remarkable in cider vinegar. Glucose and fructose were the predominant components among free sugars regardless of the kinds of vinegar. Free amino acid contents in cider, brown rice and persimmon vinegars have shown a little deviation among the same kind of vinegar samples, but were obviously more abundant than those in brewed vinegars. Color preference, sourness and sweetness of the vinegars were not statistically different (p>0.05) among four kinds of vinegars, whereas overall taste preference, background taste preference and intensity showed significant differences (p<0.05) with respect to the type of vinegar. Brewed and cider vinegars have revealed higher sensory scores in overall and background taste preference than the persimmon and brown rice vinegars. Even though there were no high relationships between minor components and organoleptic taste in commercial vinegars the ratio of acetic acid to the total organic acid was significantly correlated (p<0.01) with the overall taste preference.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.893-897
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• 2005

Effect of foliar application of stevia extract on strawberry quality was investigated. Soluble solid and free sugar contents of strawberry (SS) cultivated with foliar application of stevia extract were higher, and acidity and organic acid contents were lower than those of control. Free sugars were composed of fructose, glucose, and sucrose. Organic acids were composed of citric, malic, oxalic, succinic, and fumaric acids. Sensory evaluation revealed score of sweetness, sourness, and overall acceptability for SS were higher than those of control.