• The Korea Journal of Herbology
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• v.22 no.4
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• pp.29-34
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• 2007

Objective : Kyenegum(Galli Stomachichum Corium) has been popularly used long as the digestive. The purpose of this study was to investigate the enzymatic characteristic of Kyenegum crude enzyme. Methods : To evaluate of the enzymatic characteristic of Kyenegum, we examined the activity of Kyenegum crude enzyme from optimum solvent, optimum temperature and pH of crude Kyenegum extract. Futhermore, we examined the effects of NaCI and acidity of crude Kyenegum extract. Results : The Kyenegum was composed with crude protein about 20%, crude lipid 2%. The optimum Kyenegum dry condition, optimum extract solvent, optimum temperature and optimum pH were $4{\sim}6$ hours at $60^{\circ}C$, commercial apple vinegar, $50^{\circ}C$ and 2.0. Conclusion : The result suggests that the Kyenegum crude enzyme extract very strong enzyme in temperature, NaCl and acidity, respectively.

• The Korean Journal of Food And Nutrition
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• v.9 no.1
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• pp.52-58
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• 1996

This study was carried out 19 investigate the characteristics of pectinesterase (PE), polygalacturonase (PG), lipoxygenase(LOX) and peroxidase (POD) in hot pepper to know the effect of hot pepper on food quality during food processing and storage. The results were as follows : 1. The optimum pH of PE was pH 7.5 and the activity of PE below pH 5.5 was revealed scarcely, The concentration of NaCl and $CaCl_2$ that showed the highest activity of PE were 0.2M and 0.05M, respectively. 2. The optimum pH of PG was pH 6.0 and the activity of PG in acidity was higher than that in alkalinity. The activity of PG was maximum at 0.3M NaCl and 0.2mM $CaCl_2$. Above the concentration of 0.5M NaCl and 0.5M $CaCl_2$, the activity of PG was lower than that of PG not adding these salts 3. The optimum pH of LOX was pH 7.0 and pH 8.5. 4. The optimum pH of POD was pH 6.0 and the activity of POD was higher in weak acidity and neutrality than in alkalinity. POD activity was slightly decreased by the increase of NaCl and $CaCl_2$ concentration.

• Journal of the Korean Society of Food Culture
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• v.19 no.6
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• pp.587-597
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• 2004

Application of pheasant and soybean extracts to improve the quality of baechu kimchi was attempted. Pheasant and soybean extracts at various combinatory concentrations were added into baechu kimchi and fermented for 24 days at $10^{\circ}C$. Assay was performed on salinity, acidity, bacterial growth, sensory evaluations, and physical properties. The pH decreased, and acidity increased by fermentation time. The optimum pH 4.2 was reached within $12{\sim}15\;days$, and optimum acidity was reached within $6{\sim}9\;days$. The number of lactic acid bacteria was increased by fermentation time. Score of intensity characteristics in color. crispness carbonated taste, and overall quality were higher for the pheasant and soybean extracts added baechu kimchi(B) than for the control product(S). The result of L and a value of baechu kimchi were Higher in treatment than in control as fermentation time increased. The hardness of baechu kimchi with pheasant and soybean extracts(B) were higher than those of control(S).

• 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 Culture
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• v.9 no.1
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• pp.79-85
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• 1994

This study was conducted to determine the optimum conditions for the preparation of traditional Korean whole cabbage Kimchi with salted shrimp. Sensory, physical and chemical characteristics of Kimchi with various salted shrimp level(1.8, 3.6%), fermentation time(12, 24, 36 hrs) and storage period(1, 4, 7 days) were measured. As the fermentation time and storage day were extended, pH of Kimchis decreased but titratable acidity of Kimchis increased. The more salted shrimp in Kimchi resulted in the higher titratable acidity. The longer fermentation time and the longer storage resulted in the more citric, malic and succinic acid, and the less lactic and acetic acid in Kimchi. The optimum conditions for the preparation of Korean whole cabbage Kimchi were 3.6% salted shrimp level, 12 hours fermentation time and 84 hours(3.5 days) storage period.

• Journal of Life Science
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• v.18 no.9
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• pp.1284-1289
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• 2008

This research was conducted to elucidate the optimum conditions for the maesil vinegar fermentation by Acetobacter sp. SK-7 using evolutionary operation (EVOP)-factorial design technique. The acidity of maesil vinegar was effected by ethanol concentration in the range of 3-7% (r=-0.5166), and glucose concentration in the range of 0.1-0.5% (r=-0.5061). The acidity of maesil vinegar was not effected by differentiation of temperature in the range of 24-$33^{\circ}C$ (r=0.1082). The optimum maesil vinegar fermentation by Acetobacter sp. SK-7 as determined by the EVOP-factorial design technique was obtained at an fermentation temperature of $30^{\circ}C$, ethanol concentration of 4%, glucose concentration of 0.2%. Furthermore, the acidity of vinegar increase from an initial acidity of 5.4% to 6.365% in the third set that is nearly 1.0% by EVOP-factorial design technique

• Journal of the Korean Society of Food Culture
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• v.9 no.1
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• pp.87-93
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• 1994

This study was conducted to present a method that determine the optimum conditions for the preparation of chinese whole cabbage kimchi. After Sensory and chemical characteristics of kimchi with various salt concentration in brine, brining time and storage period at equal saltiness were measured, the optimum conditions for the preparation of chinese whole cabbage kimchi were determined with the use of the response surface methodology. The results are summarized as follows; 1. The more salt concentration in brine, the longer brining time and storage period, resulted in the lower pH and the higher titratable acidity of kimchis. As the salt concentration in brine and brining time increased, kimchi reaches at optimum titratable acidity of it within a shorter time. 2. As the salt concentration in brine and brining time increased, content of succinic acid decreased but that of lactic, acetic, and propionic acid increased. Amount of citric, malic and succinic acid decreased but that of lactic, acetic acid increased, with storage day. 3. Sensory data showed that firmness and green cabbage flavor of kimchi decreased while toughness, carbonic mouthfeel, sourness and staled flavor increased with increased salt concentration in brine, brining time and storage day. As the storage period increased, crispness of kimchi decreased. 4. The optimum conditions for the preparation of chinese whole cabbage kimchi were as follows: Optimum salt concentration in brine, brining time, and storage period were 19.5%, 3 hours and 45 minutes, and 12 hours.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.812-817
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• 2003

In the first stage, strawberry wine was manufactured in 14$^{\circ}$Brix initial sugar content, for 50 hr at 28$^{\circ}C$ using Saccharomyces kluyeri DJ97. In the second stage, the acetic acid fermentation conditions for maximun acidity (4.60%) were 1.48% initial acidity and 195.76 rpm in agitation rate for 7.34 day. The fermentation conditions for maximun Hunter color a value were 1.78% initial acidity and 117.63 rpm in agitation rate for 7.35 day. Therefore, optimum acetic acid fermentation conditions were 1.5% initial acidity and 196 rpm in agitation rate for 176 hr using Acetobacter sp. PA97.

• Korean journal of food and cookery science
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• v.11 no.1
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• pp.37-43
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• 1995

Effect of the pretreatment with acetic acid(0.01%, 0.05%, 0.1%) on the fermentation of Chinese cabbage Kimchi, and differences in the degree of maturity between Chinese cabbage blades and midribs were observed. To estimate the degree of maturity, correlation analysis was used with several variables such as pH, titratable acidity, volatile acidity, ascorbic acid content, resazurin test value and pH/acidity ratio. Based on the pH and titratable acidity, the degree of maturity of Chinese cabbage midribs fermented at 10$^{\circ}C$ until the optimum stage of fermentation increased more rapidly than those of the blades. The stage of maturity of Kimchi pretreated with 0.01% acetic acid were slightly prolonged, compared to those pretreated with acetic acid at the higher levels. The pH of Chinese cabbage midribs and blades pretreated with acetic acid was lower than those of control between 2nd and l0th day of fermentation. The volatile acidity of Chinese cabbage midribs and blades increased proportionally with the concentration of acetic acid. The ascorbic acid contents of Chinese cabbage midribs showed higher than those of Chinese cabbage blades. During the fermentation, the higher concentration of acetic acid was used, the less ascorbic acid content was remained. The pH/acidity ratio, volatile acidity, ascorbic acid content and resazurin test value of Chinese cabbage midribs and blades during Kimchi fermentation at 10$^{\circ}C$ showed good correlations with the pH and titratable acidity.

• Food Engineering Progress
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• v.21 no.4
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• pp.403-408
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• 2017

Acetic acid bacteria strains were isolated from a variety of fermented foods and fallen fruits. Among them, the strain MAK88, whose acetic acid fermentation ability, acid-tolerance, and alcohol-tolerance were high, was selected and identified as Acetobacter orientalis. A seed culture of A. orientalis MAK88 was inoculated into onion juice, and the optimum conditions of acetic acid fermentation was investigated. The optimum initial concentration of ethanol in onion juice was 5% (v/v) and in that condition, acidity was 4.31% at 144 h of fermentation. The optimum initial concentration of acetic acid was 1% and the final acidity was 5.32%. The optimum fermentation temperature was determined to be $28^{\circ}C$. The most appropriate preparation method of onion juice was to heat the onion at $121^{\circ}C$ for 15 min and produce juice with pressure followed by filtering, and then sterilization at $121^{\circ}C$ for 15 min. Prepared onion juice was used for fermentation without dilution.