• Journal of Ginseng Research
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• v.20 no.3
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• pp.299-306
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• 1996

This study was undertaken to examine the effects of fresh ginseng on the physicochemical and microbiological changes in dongchimi juice fermented under various conditions. The pH was somewhat lower in dongchimi juice added with 2.0% and 4.0% of fresh ginseng than that without ginseng, whereas the titratable acidity was higher in dongchimi juice with 2.0% and 4.0% of ginseng addition than the control. The addition of fresh ginseng to dongchimi preparation increased the numbers of total viable bacteria, lactic acid bacteria including Leuconostac mesenterotdes in dongchimi juice during fermentation. The changes in the counts of lactic acid bacteria were similar to those of total viable cells throughout the experiment except the initial stage of fermentation. However, the number of Leucosfastoc mesenternidgs decreased after the palatable stage. Key words : Panax ginseng C.A. Meyer, dongchlmi juice, pH, titratable acidity, microbiological changes.

• Korean journal of food and cookery science
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• v.15 no.1
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• pp.73-80
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• 1999

This study was carried out to investigate the effects of enzyme treatments on the functional properties of soy protein isolate (SPI) and to examine the quality attributes of soy yogurt prepared by different enzyme treatments, sweeteners and starter cultures. Enzyme treatment increased the solubility and emulsifying capacity of soy proteins, but decreased the emulsifying stability; the enzymatic activity of ${\alpha}$-chymotrypsin was higher than that of trypsin. Enzyme treatments decreased the pH of soy yogurts prepared by both culture methods, the culture of L. bulgaricus and S. thermophilus and the culture of L. bulgaricus and K. fragilis, but increased the titratable acidity, total numbers of lactic acid bacteria and yeast. Trypsin was more effective than ${\alpha}$-chymotrypsin in decreasing pH and increasing titratable acidity and total numbers of lactic acid bacteria and yeast. Fructose decreased the pH of soy yogurts more than sucrose in the culture of L. bulgaricus and S. thermophilus, and vice versa in the culture of L. bulgaricus and K. fragilis. Fructooligosaccharides were more effective in the culture of L. bulgaricus and K. fragilis than in the culture of L. bulgaricus and S. thermophilus in increasing the titratable acidity, total count of lactic acid bacteria and yeast. In sensory evaluation, soy yogurts containing trypsin treated SPI, fructose and fructooligosaccharides (75%:25%) were more acceptable than those containing untreated or trypsin treated SPI and fructose. This was because of more smooth and less sour, in which the values of pH, titratable acidity, microbial growth, and viscosity were in the range of commercial yogurts. Soy yogurts fermented by L. bulgaricus and K. fragilis showed more smooth mouthfeel than those fermented by L. bulgaricus and S. thermophilus.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.636-640
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• 2009

The effect of post-cut vanillin treatment at high concentrations on changes of quality and microorganism in fresh-cut apples was studied. Apples (Malus domestica Borkh. cv. Fuji) were sliced, treated by dipping in different vanillin solution, 0, 40, 80, and 120 mM, packed in polyethylene bag, and then stored for up to 3 weeks at $4^{\circ}C$. Changes in total aerobic bacteria, yeast and molds, browning, soluble solids, and titratable acidity during storage were investigated. Growth of total aerobic bacteria throughout storage was strongly inhibited by vanillin regardless of treatment concentrations. Growth of yeast and molds was inhibited by vanillin of all concentrations until 2 weeks of storage. Levels of browning index, soluble solids, and titratable acidity were not significant difference among the treatment conditions until 2 weeks of storage. However, when stored for 3 weeks, browning index increased more at 80 or 120 mM vanillin, while soluble solids and titratable acidity more be decreased by 120 mM vanillin as compared with other treatment conditions. These results show that the usage of vanillin in processing of fresh-cut apples had a limitation for maintaining quality.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1134-1139
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• 1998

Quality changes of filter-sterilized Yakju were examined by filtration of Yakju through membranes followed by storing at $25^{\circ}C$ for 50 days. To evaluate quality changes of filter-sterilized Yakju, pH, titratable acidity, turbidity, and viable cell numbers of total bacteria, lactic acid bacteria, and yeast were measured. Titratable acidity, turbidity and viable cell numbers of non-sterilized Yakju increased, but pH profile decreased during the storage. In filter-sterilized Yakju, titratable acidity and turbidity did not change, while viable cells of total bacteria, lactic acid bacteria, and yeast were not detected during the storage. Addition of chitosan at the concentration of 0.1% (w/v) decreased the viable cell numbers significantly showing similar pH and titratable acidity profiles with non-sterilized Yakju.

• Food Science of Animal Resources
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• v.21 no.2
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• pp.156-162
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• 2001

The quality changes of UHT market milk product were investigated by the season and storage conditions. Throughout the year, standard plate counts(SPC) wasnt increased significantly during storage at 5$\pm$1 and 7$\pm$1$^{\circ}C$ for 10 days. And except for summer, SPC was lower than 20,000 cfu/ml after storage at 10$\pm$1$^{\circ}C$ or 10 days. But SPC was rapidly increased from 3 days at 15$\pm$1$^{\circ}C$, and there was gas forming by yeast growth after storage at 30$\pm$1$^{\circ}C$. Values of pH and titratable acidity of market milk products were 6.49 to 6.71 and 0.155 to 0.16%, respectively. pH and titratable acidity were a lot changes at the temperature over 15$\pm$1$^{\circ}C$, and milk products showed a curd at 30$\pm$1$^{\circ}C$. Carbohydrate of market milk product had little difference throughout the year, whereas fat, protein and total solids of market milk products in autumn showed a little higher value than that of other seasons. There were no changes of milk composition during storage periods, but carbohydrate was decreased a little after storage over 20$\pm$1$^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.218-221
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• 2004

Irradiated red pepper powder (IRPP) was tested for its ability to retard fermentation and to maintain a high quality of Kimchi by the reduction of the initial microbial load. Kimchi containing IRPP at the doses of 0, 5, 10, 15, or 20 kGy was prepared. Quality indices for Kimchi in this study were pH, titratable acidity, reducing sugar content, total microbial count, lactic acid bacterial load, and sensory evaluation. Based on the pH and titratable acidity, the Kimchi with IRPP showed a retarded fermentation until 15 days. The number of the total aerobes and lactic acid bacteria of the Kimchi with IRPP were lower by about 1 log CFU/mL compared to control at day 0, however, the counts increased to 8.5 log CFU/mL after 10 days, which was similar to the control group. Kimchi that was fermented with 5 kGy IRPP was better than control and other treatments in odor and color, whereas the control scored highest in taste. Addition of IRPP showed a limited retardation of Kimchi fermentation without other quality deterioration.

• Journal of Life Science
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• v.7 no.4
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• pp.342-346
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• 1997

This experiment was carried out to clarify the effects of gibberellin(GA) aplication and bagging on repeening and quality in 'Delaware' grape berries. Treatments are 4 plots(2X2 factorial experiment); GA, GA+bagging, bagging and control. The clusters were dipped twice in 100 ppm GA with GA treatment : 10 days before and after the full bloom. The results obtained as follows: 1. GA treatment made the seedless grape berry reduced in the fresh weight but it hastened the ripening period about 2 weeks. 2. Total soluble solid(TSS), viscosity and pH value of berry juice increased with maturation. The concentration of TSS and viscosity were higher in GA treatment plot than GA non-treatment. 3. Berry-hardness, titratable acidity and alcohol inslouble solid(AIS) decreased with maturation. Expically berry-hardness and AIS decreased more greatly in GA non-treatment than GA treatment. 4. The concentration of anthocyanin increased with ripening but pectic substance didn't fluctuate nearly. These of anthocyanin and pectin were higher in GA non-treatment plot than GA treatment. 5. By analysis of factorial experiment GA treatment was highly significant with the $^{o}$Brix/Acidity ratio, juice viscosity and AIS, but high negatively, significant with berry-hardness and berry fresh weight. And it was significant with T S S and negatively, titratable acidity. Bagging was significant with $^{o}$Brix/Acidity ratio and AIS content, but negatively, titratable acidity. 6. Qualitative characters were high correlated with the $^{o}$Brix/Acidity ratio in simple correlation but direct effect by the path-coefficient analysis didn't coincide with simple correlation. The direct effect of pH was large and juice viscosity, the next. And that of berry-hardness was negligible but, AIS, small negatively.

• Food Science and Preservation
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• v.6 no.3
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• pp.260-263
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• 1999

This study was measured weight loss, total ascorbic acids, titratable acidity and soluble solids contents to investigate the effect of EPS(expended polystyrene foam) box. double wall corrugated paperboard box and LDPE film pouches during storage at 25$^{\circ}C$. The rate of weight loss was 5.7% in corrugated paperboard box after 10 days. but those of 20LD, 40LD film and EPS box were 1.0, 0.8, and 0.9%, respectively. Total ascorbic acid content and titratable acidity of EPS box was 15.0% and 24.4% higher than that in corrugated paperboard box, but the obvious differents were not observed among the LDPE film pouches and EPS box. The titratable acidity was decrease during storage, but total soluble solids content was slightly increase. Overall appearences of LDPE pouches and EPS box were boner than those of corrugated paperboard box.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.5
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• pp.776-782
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• 2009

This study was conducted to develop functional soybean paste with krill (Euphausiacea) as compared to a conventional soybean paste (S1). Soybean containing 10%, 20% and 30% (w/w) krill (S2~S4, respectively) was prepared and quality characteristics (moisture, crude fat, crude protein, ash, reducing sugar, pH, titratable acidity, total acidity and buffering power) were assessed during fermentation for 150 days. As well, antioxidative activities of krill soybean paste were compared to those of control soybean paste based on total phenolic compound content and free radical scavenging activity, including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) scavenging activity and the thiobarbituric acid value (TBA value). The moisture content of all samples decreased to 41.91~53.47% during fermentation, while the crude fat increased to 1.98~5.21% with increasing addition of krill. Additionally, crude protein increased slightly to 8.24~14.08% with increasing addition of krill after 120 days of fermentation. Ash content was 15.96~18.92%. The reducing sugar content of S2, S3 and S4 was higher than those of S1 with increasing length of fermentation. S2, S3, and S4 displayed progressive decreases in pH and progressive increases in titratable acidity compared to S1. The total acidity of all samples was increased, while the buffering power was decreased with increasing fermentation. Especially, the buffering power of S1 was lower than that of S2, S3 and S4. DPPH radical scavenging activity of lipophilic extracts from S2, S3 and S4 was slightly higher than those of S1. However, the radical scavenging activity of hydrophilic extracts from all samples had similar tendencies, regardless of the krill content or fermentation period. Total phenolics increased with increasing fermentation time and TBA value increased with increasing fermentation time and krill content.

• Journal of the Korean Society of Food Culture
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• v.4 no.2
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• pp.167-172
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• 1989

Kimchi during fermentation with different periods of storage at room temperature were evaluated for the textural properties, titratable acidity, pH value and thickness of leaves in salting, during fermentation. Thickness of internal leaves in Korean cabbage were decreased of 50% for external leaves. but less decreased on the thickness of leaves in salting. Cutting force of leaves were increased with salting and during kimchi fermentation before 7 days. Stress (force vs area) in kimchi and Korean cabbage was same result of cutting force. Equation of pH change was y=-0.23x+6.13 (r=-0.97). Titratable acidity equation was y=0.09x-0.01(r=0.96). A desirable pH value and titratable acidity were 4.2 and 0.63% in kimchi fermentation.