• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1017-1021
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• 1999

Shindari, a traditional low alcoholic drink in Cheju island, was prepared with nuruk and the rice porridge. The rice porridge was fermented with 10% nuruk at a temperature of $25^{\circ}C,\;35^{\circ}C,\;45^{\circ}C$ for 24 hours. In all temperature, total acidity and oBrix were increased gradually and pH were decreased gradually and viscosity were considerably decreased after 2 hours and then slightly decreased. Alcohol contents were also increased during fermentation and especially at $45^{\circ}C$. The organic acids were mainly found phytic acid and succinic acid. The fermented liquids rice porridge contained maltose and glucose as free sugar, amount of them increased during fermentation. Lactic acid bacteria cell count increased at higher tem perature of fermentation and reached to $10^{7}\;cfu/ml\;at\;35^{\circ}C$ for 10hr. In conclusion, the optimal fermentation conditions Shindari preparation were at $35^{\circ}C$, 24hrs. pH, titratable acidity, viscosity and soluble solids in the optimal fermentation condition were 4.2, 0.18%, 190cp, $12.2^{\circ}Brix$, respectively.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.701-707
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• 2003

Kimchi was prepared with the addition of 2.5％ and 5.0％ Monascu purpureu koji(MPK) paste (20％) and were fermented at 20$^{\circ}C$ for 18 days. The quality and sensory characteristics of the kimchi were evaluated by analyzing the pH, acidity, number of viable cells, the concentration of reducing sugar, and sensory properties during fermentation. The pH and titratable acidity of the kimchiprepared with MPK(MPK kimchi) were higher and lower, respectively, than those of the control kimchi. The MPK kimchi showed high 'L' and 'b' values during storage, but the 'a' values were low. The contents of the reducing sugar of the MPK kimchi tended to increase during fermentation, particularly after six days. The number of total microbial cells, lactic acid bacteria and yeast in the MPK kimchi were lower than those of the control kimchi until 3 days of fermentation. However, the number of these bacteria in the MPK kimchi and the control kimchi after six days of fermentation was similar. The sensory score of the kimchi with 2.5％ and 5.0％ added MPK paste were significantly higher than the control groups in terms of the sweetness and overall acceptability.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.527-533
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• 2012

This study was carried out to investigate the effects of aminoethoxyvinylglycine (AVG) application and heat treatment on fruit quality of 'Fuji' apples during CA storage. AVG ($75mg{\cdot}L^{-1}$) was applied to 'Fuji' tree at 150 and 175 days after full bloom (DAFB) and the fruit were harvested at 185, 195, and 205 DAFB, respectively. Respiration rate and ethylene production of fruit applied with AVG were greatly reduced more than those in control. Flesh firmness and acidity of fruit applied with AVG were higher than those in control. Flesh browning occurred in all of the control fruit regardless of harvest date. However, AVG-treated fruits were free of flesh browning except for late harvested fruits. At 185 DAFB, 'Fuji' apples were harvested and prestorage heat treatment was done for 3 days at $38^{\circ}C$ and 6 hours at $46^{\circ}C$. Heat treatment at $38^{\circ}C$ and $46^{\circ}C$ prior to CA storage greatly reduced respiration rate and ethylene production. The incidence of flesh browning were 35%, 14%, and 5%, in control fruit, heating at $38^{\circ}C$ and $46^{\circ}C$, respectively. The titratable acidity was lower at heated apple than at controlled one.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.37-48
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• 2014

The purpose of this study is developing a formulation with an optimum sensory point by using yogurt added with rice flour and pregelatinized rice flour(alpha rice flour) optimized by response surface method(RSM). The pH, acidity, sugar content, viscosity and number of lactic acid bacteria during fermentation of two types of yogurt(added with rice flour and pregelatinized rice flour) optimized by RSM were analyzed As the fermentation time of both types of yogurt increased, pH showed decreasing trend. The titratable acidity showed increasing trend as fermentation time increased. Sugar content decreased as fermentation time increased. The reasons are believed to be the sugar decrease during glycolysis and lactic acid fermentation. Viscosity was the highest at 6 hours of fermentation. After 10 hours of fermentation, the viscosity was higher than it was before the fermentation. The number of lactic acid bacteria of yogurt added with rice flour and pregelatinized rice flour was 7.43~9.00 log CFU/mL, which is more than optimum value. Therefore, it is possible to confirm that adding rice flour during yogurt manufacturing increases the number of lactic acid bacteria.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.307-313
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• 2010

Yogurt base was prepared from skim milk added with 0.5, 1.0 and 1.5% (w/v) black garlic extracts(BGE, 60 brix), fellowed by fermentation with Lactic acid bacteria (the mixed strain of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus) at $42^{\circ}C$ for 24 hr. The yogurt products were evaluated for acid production (pH, titrable acidity), number of viable cells, viscosity, color value, and sensory properties. The pH of yogurt with BGE was below 6.0 at 6 hr fermentation, after which it was rapidly acidifies. Aftert 24 hr, the titratable acidity of yogurt with 1.5% BGE was 0.74%, which was 5.7 times higher than that before fermentation. There was no significant difference in viable cell count between the samples after 3 hr fermentation. The viscosity of yogurt was decreased by the addition of BGE. As the percentage of BGE increased, the L value (lightness) decreased while the a value (redness) and b value (yellowness) increased. The overall sensory score of yogurt with BGE was lower than that of yogurt with only skim milk. Therefore, moderate addition of BGE was below 1% for the preparation of yogurt.

• Journal of the Korean Society of Food Culture
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• v.12 no.2
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• pp.183-188
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• 1997

This study was carried out in order to analyze the changes in general compounds and sugars of traditional Korean soy sauce with varying Meju concentrations (Meju-water ratios of 1 : 4 and 1.3 : 4) and ripening periods (up to 2 years). Along with ripening period, pH decreased and titratable acidity, total acidity and crude protein contents increased, which were higher in 1.3 : 4 than in 1.4. Buffering power increased significantly with increasing ripening period. Crude fat content was higher in 1.3 : 4 than 1 : 4. Moisture content decreased and pure extract content increased significantly with increasing ripening period, which was high in 1.3 : 4. Salt contents increased with increasing ripening period, but decreasd in soy sauce ripened for 2 years. As the result of sugar analysis, reducing sugar showed slow increase with increasing ripening period. Among detected free sugars, galactose was present in the highest concentration and the rest were in the sequence of glucose, fructose. Total free sugar content was highest in soy sauce ripened for 150days in 1 : 4 and 210 days in 1.3 : 4.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.186-190
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• 2009

Four different mixing ratios of Rose rugosa Thun and Vitis amurensis (Moru) were prepared. These included Rose rugosa Thun two vs. Moru one (Moru 33), Rose rugosa Thun one vs. Moru two (Moru 67), Rose rugosa Thun one vs. Moru five (Moru 83), and Moru (Moru 100). Their physiochemical changes were investigated during 28 days of fermentation followed by aging. The final brix, pH, and total titratable acidity values of the four experiments were in the following ranges: 6.0-8.2$^{\circ}$Bx, 3.87-4.03, and 0.94-1.18%, respectively. Final ethanol contents were 6.5% in Moru 33, 11.8% in Moru 67, 11.1% in Moru 83, and 11.4% in Moru 100. As the amount of Rose rugosa Thun increased, anthocyanin content, color intensity, organic acid, and free amino acid concentrations were reduced. These findings demonstrate that the supplementation of Rose rugosa Thun to Moru prior to alcohol fermentation may help change the acidity, colour, and taste in the final product.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.451-459
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• 2013

Korean black raspberry fruits (bokbunja) were collected from 11 different producing regions, and commercial black raspberry wines were obtained from 24 manufacturers. Samples were analyzed for soluble solids, titratable acidity, pH, reducing sugar content, hunter color values, intensity, hue, total phenolic content, and organic acids. The fruit samples showed similar pH levels (3.43-3.52), but significantly differed in total acidity levels (9.98-16.2 g/L). The predominant organic acids in the fruit samples were citric acids (1.39-5.63 mg/mL) and succinic acids (0.25-6.53 mg/mL). Among the samples, black raspberry fruits from Goksung and Nonsan showed the lowest levels of total phenolic content, and the lowest values in intensity. The fruits from Jeongeup and Sunchang showed higher levels of phenolic content, soluble solids, and intensity. Some wine samples, including BH, KO, SR, and SE, showed overall high levels of phenolic content, organic acids like citric and succinic acid, and color values such as $a^*$, $b^*$, and intensity. Other wine samples, including DW, SC, GJ, and NB, were high in acetic acid, color values like $L^*$, and hue.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.21-30
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• 2008

In this study, the antioxidant activities of 27 medicinal herbs and plants were measured. The dried medicinal herbs and plants were pulverized and extracted by water, 15% ethanol, and 45% ethanol, respectively at above $80^{circ}C$ for 90 minutes. The original and diluted extracts were tested for their antioxidant activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity assay. Cornus officinalis (C) and Scutellaria baicalensis (S) were selected to develop rice wines with higher antioxidant activities, based on the result of the 45% ethanol extraction. The rice wine developed using sample showed the highest antioxidant activity as comparing to those of other commercial rice wines. The rice wine samples were analyzed for titratable acidity, pH, $^{\circ}Brix$, reducing sugar content, color (L, a, b), amino-acidity, and ultraviolet absorption. The preferences for color, aroma, and overall acceptability were determined using a 9-point hedonic scale by 150 consumers. The sweetness, sourness, fruitiness, color, and medicinal herb-taste levels of the developed rice wines were also evaluated, using a 9-point just-about-right scale. The mean overall acceptability score of c (5.54) was higher than that of sample S. Based on the results, the sourness and medicinal herb-taste levels of sample s should be modified to higher levels, and the fruitiness of sample S also needs to be adjusted. For a future study, the final compositions of the developed rice wines will be adjusted for product launching based on the preference test data acquired in this study.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.8-17
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• 2004

The effect of chlorella extract on the growth and acid production of yoghurt starter was investigated in order to prepare the yoghurt added with chlorella extract. The various levels of chlorella extract powder were added to skim milk medium and the medium was fermented by single or mixed culture of 4 types of lactic acid bacteria such as Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus bulgaricus. The changes in acid production(pH, titratable acidity) and number of viable cells of the medium during fermentation in skim milk added with chlorella extract powder have determined. When chlorella extract powder was added to skim milk medium at the levels of 0.5%, 1.0%, 2.0%, and 3.0%, the addition of 0.5% chlorella extract powder with the single culture of Str. thermophilus, Lac. casei, and Lac. bulgaricus showed the highest number of viable cell counts after 9 hours incubation. And also all single cultures of the yoghurt starter produced the higher amounts of acid with the addition of 0.5% chlorella extract powder. When chlorella extract powder was added to the medium at the levels of 0.25%, 0.5%, 1.0%, and 2.0%, the addition of lower lever(0.25∼0.5%) of chlorella extract powder with the mixed culture of the lactic acid bacteria showed more the acidity of pH and the number of viable cell counts. Among the treatments tested, the addition of 0.25% chlorella extract powder with the mixed culture of Str. thermophilus and Lac. casei produced the highest number of viable cell counts after 12 hours incubation. Therefore it was suggested to manufacture the yoghurt with the addition of 0.25% chlorella extract powder and the inoculation of mixed culture of Str. thermophilus and Lac. casei for on the stimulation of growth of the yoghurt starter.