• Food Science and Biotechnology
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• v.18 no.1
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• pp.12-17
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• 2009

The effect of kimchi, traditional Korean fermented vegetables, on inactivating food-borne pathogens and the kimchi factors affecting the antimicrobial activity were investigated. More cells of Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella typhimurium were inactivated in the kimchi that had low pH and high titratable acidity. Of the raw ingredients in kimchi, raw garlic showed the strongest antimicrobial activity against the pathogens. When kimchi was fermented at 0, 4, 10, or $20^{\circ}C$ to pH 4.4, higher kimchi fermentation temperature resulted in higher titratable acidity. The greatest inactivation of S. typhimurium occurred in kimchi fermented at $20^{\circ}C$, while L. monocytogenes were inactivated in kimchi fermented at $0^{\circ}C$ in situ. This study showed that appropriately fermented kimchi can inactivate various food-borne pathogens and that the fermentation temperature of the kimchi is an important factor in determining the ability of the kimchi to inactivate specific pathogens. Lactic acid bacteria (LAB) multiplication and organic acids produced according to LAB metabolism play a role in inactivating food-borne pathogens in kimchi.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.247-257
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• 2010

The purpose of this study was to investigate the quality characteristics of Gamgyul-Injeulmi with different ratios of Citrus mandarin powder(0, 3, 6, 9, 12%) during storage. The moisture contents of the Gamgyul-Injeulmi decreased during storage but the moisture content of control(containing 0% Citrus mandarin powder) was almost constant. According to amylograms, gelatinization temperatures were lower in the samples containing Citrus mandarin powder compared to the control. More additions of Citrus mandarin powder caused lower viscosity and breakdown values but higher setback values. The pH of all samples decreased during storage but as more Citrus mandarin powder was added the changes in pH were less. The titratable acidity of all samples increased during storage and more additions of Citrus mandarin powder resulted in higher titratable acidity. For the Hunter's color values during storage, L and a values decreased but b values was increased except for the control. Textural analyses of the Gamgyul-Injeulmi showed that hardness, gumminess and chewiness increased, whereas adhesiveness, cohesiveness and springiness decreased during storage.

• Food Science and Preservation
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• v.8 no.4
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• pp.345-350
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• 2001

This study was measured weight loss, total ascorbic acid, titratable acidity, and soluble solids content to investigate the effect of EPS(expanded polystyrene foam, foaming rate 55 times V/W) box, LDPE film pouches and double wall corrugated fiberboard box during storage at 20$\^{C}$. Weight loss of apple packed with corrugated paperboard box after 40 days storage was 5.7%, arid those of LDPE, CE(zeolited coated film) film and EPS box were 0.2-0.5%. Ascorbic acid content of apple packed with LDPE, CE, EPS was higher than that of control. Titratable acidity and total soluble solid content of control were changed 40% and 10%, but the EPS were changed 27% and 4%, respectively. Overall appearances of ‘Fuji’apple packed with LDPE, CE and EPS were better than that of control.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.1
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• pp.62-70
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• 2000

This study was conducted to investigated the kimchi quality of the addition of green tea extract and green tea leaf. Kimchi was examined for pH, titratable acidity, the changes in the number of microorganism, color,sensory evaluation . The pH and titratable acidity of kimchi at the addition of 5%, 1% of green tea extract and green tea leaf were higher and lower than those of control kimchi. the number of total microoranism at 21 days. were detected much more in the kimchi added green tea extract and green tea leaf than in control. The number of coliforms up to 7 days of fermentation were detected. And those at 14-21 days were not detected but those of 28 days were detected. The number of coliforms at 28 days were most lowest in the kimchi added green tea extract 3%. The number of lactic acid bacteria were detected more in the kimchi added green tea leaf. As a result of sensory evaluation during fermentation, the kimchi added green tea extract 5% was the highest score in carbonated taste. texture and overall quality. As the result of correlation between sensory characteristics and mechanical characteristics, it was found that sensory characteristics of sour taste is negatively related to the mechanical characteristics of L value, while it is positively related to the texture. The a values is negatively related to the sensory characteristics of overall quality. The b values is positively related to the sensory characteristics of sour taste.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.5
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• pp.419-424
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• 2000

To develop a functional Kimchi utilizing onion, 5 different Kimchi with onion used as a major ingredient were formulated. The changes in pH. titratable acidity, reducing sugar. total bacterial count, and the number of lactic acid bacteria in the process of fermentation were studied A. onion Kimchi Control. B : onion Kimchi added with oyster, C : onion Kimchi added with salted shrimp, D : onion Kimchi added with oyster, cucumber, and a bit of radish, E : onion Kimchi added with salted shrimp, cucumber, and a bit of radish. pH of onion Kimchi decreased during storage, but titratable acidity increased. The pH values of onion Kimchi were not significantly different among groups, the changes in pH during fermentation were the lowest in A, and changes in B and D were lower than those of C and E. Salt concentration tended to decrease during the fermentation process, and the changes in salt concentration were lower in D and E than in B and C. Reducing sugar content maximized at 4 days of fermentation and decreased after 12 days. The number of lactic acid bacteria increased during first 4 days of fermentation and decreased after 12 days. Total lactic acid bacterial count were the most lowest in A.

• Korean journal of food and cookery science
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• v.32 no.2
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• pp.211-221
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• 2016

Purpose: This study was conducted to investigate the physical and sensory properties of seasoned powders utilizing tomato. Methods: Tests of salted tomato powder were performed for the physiochemical properties (moisture content, pH value, titratable acidity, color value, salinity content, and solubility content), sensory characteristics and sensory preference. Results: Moisture content of salted tomato powder containing fully ripened tomato (RT) was higher than that of salted tomato powder containing cherry tomato (CT), with the exception of CT 10%. The pH values of RT was relatively high and increased salt addition increased the pH as well. The titratable acidity was opposite the result of pH measurement. The color values of RT was higher than that of CT for the L, a, and b values. The salt content of RT was higher than that of CT. RT 10% showed the highest dissolution followed by CT 10%. In addition, the sensory preference for CT 10% was the highest, with the best scores for appearance and taste. Conclusion: It was concluded that 10% salt addition is the most suitable sensually for the manufacture of salted tomato powder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.390-395
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• 1999

The cucumber pickles(pieces types), soaked at 10, 15, and 20% brine concentrations, were fermented for 7 days at 25oC. The pH of sample in 10% brine was lowered faster than that of others. To reach pH 3.7, it took 4 days(10%) , 6 days(15%) and 7 days(20%), respectively. The salt permeated into cucumber rapidly, and it took only 1 day to reach maximum content, thereafter salt contents were maintained constant. The titratable acidity and turbidity of cucumber pickle liquids were increased with fermentation time. Sensory evaluation showed that taste and smell of fresh cucumber, color and texture were decreased, while yeast moldy smell and acidic taste were increased as fermentation proceeded. Higher scores were obtained in acidic taste and smell, yeast moldy taste and smell in case of fermented sample in 10% brine for 4 days. It was concluded that the quality of cucumber pickle was influenced by the salt concentrations of brine.

• Food Science and Preservation
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• v.10 no.4
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• pp.470-475
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• 2003

The response surface methodology was performed by central composite design for moisture content, titratable acidity, hunter's color value and organoleptic properties based on drying temperature and time of Citrus, to apply basic data to preparation of dried Citrus. Moisture content, b value and organoleptic color were affected by drying temperature ; That decreased with increase of drying temperature. Titratable acidity was affected by drying time. Organoleptic flavor and taste were affected by drying temperature and time. The optimum drying conditons for organoleptic taste were 67.56$^{\circ}C$ in drying temperature and 8.06 hr in drying time.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.289-294
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• 2007

For the purpose of developing a functional yogurt, a new type of yogurt was prepared. To manufacture this new yogurt, 12% skim milk was added to the hot water extract of black soybeans. The yogurt was then evaluated for its acid production(pH and titratable acidity), number of viable cells, viscosity, quality-retention properties, and sensory properties. The titratable acidity of the yogurt with the added 5% black soybean hot-water extract was higher(2.07%) than that of the yogurt without the added extract(1.80%). The viscosity of the yogurt made by adding 5% black soybean hot-water extract was higher(5,040 cps) than that of the yogurt made with only skim milk(2,740 cps). Lactic acid bacteria propagation was stimulated by the addition of the 5% black soybean hot-water extract. When the yogurt prepared with the black soybean hot-water extract was kept at $7^{\circ}C$ for 14 days, its quality-retention was comparatively good. Finally the overall sensory score of the yogurt made with the added 5% black soybean hot-water extract was slightly lower than that of the yogurt made with only skim milk.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.545-550
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• 2001

Effects of high hydrostatic pressure on pH, titratable acidity, color, hardness and microorganisms of Chinese Cabbage Kimchi were investigated. Kimchi was pressurized at $200{\sim}600$ MPa for 5 min. There were no significant differences in color and hardness between control and pressurized Kimchi (p>0.05). Total aerobes and lactic acid bacteria were effectively inactivated by high hydrostatic pressure above 400 MPa. Changes in pH, titratable acidity, color, hardness and microbial counts for 4 weeks storage of Kimchi were investigated Kimchi was pressurized at 400 MPa for 5 min and stored at $4^{\circ}C$. The pH of control decreased to 3.94 but pressurized Kimchi maintained its initial pH value throughout the storage. The color of control showed significantly low values compared with pressureized Kimchi (p<0.05), but hardness was not significantly changed (p>0.05). Total aerobes and lactic acid bacteria in the control were reduced from the initial value of $10^8{\sim}10^9$ CFU/mL to $10^6$CFU/mL after 4 weeks storage. Whereas microbial counts in pressurized Kimchi was maintained about $10^3{\sim}10^4$ CFU/mL during storage.