• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.715-720
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• 2005

This study was carried out to investigate the effect of chitosan-liquid calcium (CLC) on the high-calcium kimchi fermentation. The $0.5\%$ of CLC retarded the decreasing rate of pH and the increasing rate of titratable acidity, and these effects were more conspicuous with liquid calcium. Total microbes and lactic acid bacteria counts were lower in CLC $(0.5\%)$ added kimchi during fermentation. The a-value of kimchi juice was gradually increased but the L- and b-values were decreased. The calcium content of the kimchi supplemented with $0.5\%$ of CLC was maintained in the range of $207\~228\;mg\%$. In sensory evaluation test of $0.5\%$ CLC-added kimchi, the staled flavor was decreased, the crispness was maintained and the overall taste was increased to highest level after 15-day fermentation.

• Food Science and Preservation
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• v.18 no.4
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• pp.436-441
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• 2011

The change in physicochemical and sensory properties and bioactive compounds of Campbell grape juice has been investigated for 30 days at $-5^{\circ}C$. The pH and sugar/acid ratio of the cold stabilized juice increased, while titratable acidity and soluble solids decreased as cold stabilization period is prolonged. Juice samples became lighter, yellowish to brownish and lesser red in color as can be observed with the increasing $L^*$ and $b^*$ values, and decreasing $a^*$ value, respectively. The juice cold stabilized for a shorter period of time showed higher levels of bioactive compounds and radical scavenging activity, and was more preferred by the panelists than the juice cold stabilized for a longer period of time. These results suggest that cold stabilization period affected the quality characteristics of grape juice.

• Korean Journal of Plant Resources
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• v.27 no.6
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• pp.701-706
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• 2014

Three highbush blueberries (Vaccinium corymbosum cvs. Bluecrop, Coville, and Northland) grown in an open field and in a rain shelter were compared to evaluate the potential benefits of rain-sheltering systems on growth and fruit quality. Shrubs grown in rain shelter flowered 5-14 days earlier and were in full bloom earlier than those in the open field. All three cultivars set fruit by nearly 90% of flowers when they were grown in the open field, but was markedly reduced when they were grown in the rain shelter, to approximately 50% for 'Bluecrop' and 'Coville'. Fruit sets ratio of 'Northland' grown in the in the rain shelter was 14.5. Fruit from greenhouse-grown 'Northland' were larger, heavier, and had more seeds per berry. Soluble sugar content (SSC) of fruits varied both with the cultivars and growing conditions. SSC of fruits grown in the greenhouse was higher in 'Bluecrop' compared to that grown in the field, but this pattern was reversed in 'Northland'. Titratable acid was significantly higher in fruits from rain shelter-grown shrubs of both 'Bluecrop' and 'Northland' than in fruits from open field-grown shrubs (P < 0.05), although there was no difference in TA with respect to growing conditions for 'Coville'. The number of seed per fruit, fruit length and diameter, weight, SSC, and TA were similar in 'Coville' shrubs grown in the open field and the rain shelter. Fruit firmness of 'Bluecrop', 'Coville', and 'Northland' was higher in the rain shelter than in the open field. 'Coville' and 'Northland' fruits harvested in the open field had higher blue chroma than those harvested in the rain shelter. However, this pattern was reversed for 'Bluecrop'. On the whole, sheltering from rain affected most fruit characteristics of the three cultivars differently. Therefore, suitable blueberry cultivars for the rain shelter should be chosen by purpose.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.491-497
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• 2016

The objective of this research was to determine the fermentation and quality properties of soy yogurt incorporating insoluble components fermented with Streptococcus thermophilus (S. thermophilus) and Lactobacillus bulgaricus (L. bulgaricus) for 24h. Boiled soybeans were ground and reconstituted into equivalent total solids (18%). After soymilk was homogenized with sugar, it was pasteurized in a water bath at $90^{\circ}C$ for 30 min. Two kinds of lactic acid bacteria were inoculated into two types of soymilk after cooling down $40{\sim}45^{\circ}C$ and fermentation at $37^{\circ}C$ for 24h. Titrable acidity, pH, viscosity, sugar content, and number of viable cells were determined in triplicate. Soy yogurt fermented with L. bulgaricus did not reach pH 4.5, where as S. thermophilus was considered good for achieving pH 4.08 and titratable acidity of 2.27% for 24 h. Soy yogurt fermented with S. thermophilus had a higher viscosity and lower sugar contents than that fermented with L. bulgaricusas incubation time increased. Total viable count was $1.80{\times}10^{10}CFU/mL$ on S. thermophilus and $2.16{\times}10^8CFU/mL$ on L. bulgaricus after 24 h at $37^{\circ}C$. However, there was no significant difference in sensory intensities and preference between the two samples. As a result, S. thermophilus was identified as a better culture than L. bulgaricus for the manufacture of soy yogurt incorporating insoluble components.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1367-1372
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• 1998

The studies were carried out to investigative effects of Lithospermum erythrorhizon, Glycyrrhiza uralensis 3% (LG) with and without dipping of salted Chinese cabbage in 1% chitosan solution(LGDC) on fermentation of kimchi at $10^{\circ}C$ during 25 days. The pH and titratable acidity of kimchi with LG and LGDC were higher and lower, respectively, than that of control. Viable cells of total bacteria, lactic acid bacteria, Leuconostoc sp. and Lactobacillus plantarum in kimchi added with LG and LGDC were shown inhibitory effect about $1.6{\sim}2.1,\;1.2{\sim}2.9,\;0.8{\sim}2.2,\;0.7{\sim}1.6$ log10 cycle, respectively. Specially Leuconostoc sp. and L. plantarum was very inhibited than in control from 0 day. The sour taste of LG and LGDC added kimchi was changed more slowly than that of control during fermentation of kimchi. But flavor, color and overall acceptability did not show significant difference(P<0.05) between treatments. The shelf-life of LGDC added kimchi was extended over 10 days compared with control.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.448-457
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• 2012

The predictive ability for off-flavor development and quality change of ground beef was evaluated using a microbial time temperature indicator (TTI). Quality indices such as off-flavor detection (OFD) time, color, pH, volatile basic nitrogen (VBN), aerobic mesophilic bacteria (AMB) counts, and lactic acid bacteria (LAB) counts were measured during storage at 5, 10, 15, and $25^{\circ}C$, respectively. Arrhenius activation energies (Ea) were estimated for temperature dependence. The Ea values for TTI response (changes in titratable acidity (TA)), VBN, AMB counts, LAB counts, and freshness, which is defined based on OFD time for quality indices of ground beef, were 106.22 kJ/mol, 58.98 kJ/mol, 110.35 kJ/mol, 116.65 kJ/mol, and 92.73 kJ/mol, respectively. The Ea of microbial TTI was found to be closer to those of the AMB counts, LAB counts, and freshness. Therefore, AMB counts, LAB counts, and freshness could be predicted accurately by the microbial TTI response due to their Ea similarity. The microbial TTI exhibited consistent relationships between its TA change and corresponding quality indices, such as AMB counts, LAB counts, and freshness, regardless of storage temperature. Conclusively, the results established that the developed microbial TTI can be used in intelligent packaging technology for representing some selected quality indices of ground beef.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.236-242
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• 2010

The objective of this study was to investigate the potential of the application of kimchi LAB as starter culture in the production of fermented sausages. For this, the solid-state model media composed to simulate the substantial conditions of meat mixtures were fermented for 120 h after the treatment with different concentrations of kimchi (0.5, 1.0, 1.5, 3.0, and 5.0%) and lyophilized kimchi-powder (0.2 % and 0.5%). During the fermentation period, the growth of total viable cells and LAB, and the changes of pH and titratable acidity were investigated. The initial LAB counts ranged from 7.18 to 8.34 Log CFU/ mL for kimchi media and from 6.93 to 6.94 Log CFU/mL for kimchi-powder media depending on the added concentrations. The kimchi LAB in this study were not influenced by the immobilized condition for their adaptation and growth by showing no lag phase and thus acted similar as in the submerged medium. The initially increased counts reached around 9 Log CFU/ mL in 12 h independent of the concentrations of a ded kimchi. However, the growth and metabolic activity of kimchi-powder LAB were influenced by the immobilized condition. Supposedly, as the nutrient supply in solid-state depended solely on diffusion, these differences in the souring properties were caused by the LAB topography in the medium matrix. Nevertheless, the differences in the numbers of LAB between two media were less than 0.5 Log units and the pH drop in the solidstate batches was quite rapid and reached low values. Therefore, it can be assumed that kimchi and kimchi-powder LAB showed the utility as the substitute of commercial starter culture even without a rehydrating pretreatment.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.466-471
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• 2002

Effect of anti-microbial agents, such as alcohol, garlic, chitosan, K-sorbate, mustard, or pasteurization on the quality of traditional kochujang was investigated during storage at $30^{\circ}C$ for 24 weeks. The pH of kochujang decreased during storage and titratable acidity changed little in the group of mustard and garlic addition. Reducing sugar increased during storage, with higher values for K-sorbate of alcohol added groups than the other groups. Alcohol contents increased during storage with higher values in control or chitosan added group. Amino nitrogen contents of kochujang decreased gradually during storage and were lower in control or chitosan added group. Ammonia nitrogen contents were lower in alcohol, garlic, K-sorbate or mustard added kochujang. The content of total free amino acid increased slightly during storage and were higher in pasteurized, garlic or alcohol added kochujang. After 24 weeks of storage, the results of sensory evaluation showed K-sorbate, garlic or alcohol added kochujang were more acceptable than control in the sense of taste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1021-1027
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• 1997

$CO_2$production in fermentation of dongchimi was measured and interrelated with changes in pH and titratable acidity. The effects of salt content and temperature on $CO_2$production rate were analysed. Fermentation of dongchimi showed drastic pH decrease in early stage and subsequent levelling off around 3.9, with linearly increased acidity up to 0.3~0.4% optimum quality. $CO_2$production of dongchimi could be analysed to consist of two consecutive stages of constant rate. The first stage $CO_2$production of higher rate moved to the second stage of lower rate when acidity rose beyond 0.3%. When compared to those of 1 and 2% salt content, dongchimi of 3% salt showed lower $CO_2$production rate in the 1st stage and slower acidity change through the whole fermentation period. However, it resulted in the product of highest $CO_2$accumulation at optimal ripeness because of consistent $CO_2$production of longer 1st stage period and relatively high $CO_2$production rate in 2nd stage. $CO_2$production depended on temperature less compared to acidity change(activation energy: 57.3 and 44.3kJ/mol for $CO_2$production of 1st and 2nd stages, respectively; 79.3kJ/mol for acidity change), which means higher ratio of $CO_2$production rate relative to acidity increase at lower temperature. Slower increase in acidity at low temperature also was shown to extend the period of 1st stage $CO_2$production. Therefore, low temperature fermentation was effective in producing the high $CO_2$content dongchimi at adequate acidity, which is desirable organoleptically.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.601-605
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• 1997

Physicochemical properties of kochujang and doenjang using extrudated wheat flour(EWF) during aging were evaluated. Moisture content and crude protein were no great changes during fermentation and among samples(En, wheat flour, and wheat). NaCl and pH value were decreased(pH was decreased from 5.1 to 4.7 for kochujang and 5.4 to 5.0 for doenjang in EWF) and while titratable acidity increased during aging in each samples(8.7 to 9.1 for kochujang and 11.0 to 11.3 for doenjang in EWF). Amino acid type nitrogen and color value were decreased. En had the highest a value(5.9 for kochujang and 5.3 for doenjang) after 30 days fermentation. This results showed the applicability of good quality of kochujang and doenjang prepared with EWF.