• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1738-1742
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• 2003

The whole plant of crop maize was chopped and ensiled in double-layered polyethylene bags to determine the influence of residual sugar on the fermentation of lactic acid and aerobic stability by L. buchneri in whole crop maize silage made in airstress condition. There were a total of six treatments used in this experiment as follow: added 25 g de-mineralised water per kg chopped maize serving as control (con), 37.5 g glucose solution containing 12.5 g glucose ($g_1$), 75 g glucose solution containing 25 g glucose ($g_2$), 25 g, L,.buchneri suspension intended for $10^6$ cfu $g^{-1}$ (L.b.), $g_1$+L.b. and $g_2$+L.b. All silos were opened at day 91 after ensiling for measuring the pH values, microbiological enumeration, fermentative products and aerobic stability. The dry matter loss increased significantly (p<0.01) due to inclusion of sugar or L. buchneri. The lower lactic acid concentrations were observed (p<0.01) in silages inoculated with L. buchneri only or in combination with sugar addition than the correspondent uninoculated silages. Compared with control silage, ethanol production was about 3 or 6-fold higher due to addition 12.5 or 25 g glucose per kg chopped maize at ensiling. The silages added with sugar contained less acetic acid concentration (p<0.01) than control, but silages inoculated with L. buchneri showed the contrary effects (p<0.01) at different sugar levels. No butyric acid was found in uninoculated silages, silages inoculated with L. buchneri. producted more propionic acid, 1-propanol and butyric acid. Lactic acid bacteria counts increased markedly (p<0.01) due to inoculation with L. buchneri, whereas it was reduced (p<0.01) by added sugar. No significant difference was observed in count of yeast, but inoculation with L. buchneri shows a decreasing trend. Mould count in all silages was less than 2 (log cfu $g^{-1}$). The added sugar had negative effects on aerobic stability of maize silage made under air-stress conditions, whereas inoculation with L. buchneri improves (p<0.01) the aerobic stability.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.609-616
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• 2006

The effects of purified licorice (Glycyrrhiza uralensis) extract (PLE) as a sugar substitute on kimchi quality were evaluated by investigating acid formation, growth of lactic acid bacteria, sensory properties, and volatile odor components of PLE-added kimchi. The pH of kimchi with higher amounts of added PLE increased slightly with two or three days ripening. The acidity of unripened kimchi or kimchi ripened for one day significantly increased with addition of PLE, while that of kimchi ripened for two or three days decreased significantly (p<0.05). Addition of PLE had no significant effect on the lactic acid bacteria count of kimchi compared to that of sugar. Overall acceptability and taste of 0.005 or 0.01% PLE-added kimchi ripened for two to three days were higher than those of other samples, whereas addition of more than 0.01% PLE to kimchi unripened or ripened for one day resulted in lower overall acceptability and taste than the reference sample. Diallyl sulfide and methyl trisulfide were newly produced by ripening of kimchi, and the amounts of some volatile odor components in kimchi were also changed during ripening.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.263-267
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• 1997

Red seabream strips were decontaminated by dipping with solutions of 0.25~1.0% acetic, lactic, or citric acids for 5min. Control strips were dipped with tap water only for 5min. All strips were individually placed in plastic bags and stored at 4$^{\circ}C$. Acetic acid(AA) treatments were completely inhibited aerobic spoilage bacteria(areobic plate count : APC) compared to the initial controls for 6 days. Treatments of either lactic acid(LA) or citric acid(CA) completely inhibited APC compared to the initial controls for 3 days. Red seabream strips treated with AA extended microbiological shelf-life for 12 days.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.598-603
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• 2012

Beef qualities which can be properly predicted by time-temperature integrator (TTI), a chromatic indicator, were selected in terms of its similarity of temperature dependence between beef qualities and TTI, denoted by Arrhenius activation energy ($E_a$). The high similarity is required to afford accurate prediction. A devised enzymatic TTI based on laccase (an oxidase), which catalyses the oxidation on 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) producing color development, was applied. The factors of beef quality, such as volatile basic nitrogen (VBN), pH, color (CIE $L^*$, $a^*$), Warner-Bratzler shear force (WBSF), Pseudomonas spp. count, and lactic acid bacteria (LAB) count were considered for the selection. $E_a$ (55.48 kJ/mol) of the TTI was found to be similar to those of the beef qualities (all referred) in the order of LAB count (53.54 kJ/mol), CIE $a^*$ value (61.86 kJ/mol), pH (65.51 kJ/mol), Pseudomonas spp. Count (44.54 kJ/mol), VBN (67.98 kJ/mol), WBSF (40.67 kJ/mol), and CIE $L^*$ value (33.72 kJ/mol). The beef qualities with more similar $E_a$ to that of the TTI showed less difference between real and TTI predicted levels. In conclusion, it was found out that when applying TTI to food packages, their $E_a$ similarity should be checked to assure accurate estimation of food quality levels from TTI response.

• Food Science and Preservation
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• v.16 no.6
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• pp.804-809
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• 2009

Recently, many Koreans have started to consume aged kimchi fermented long-term at low temperatures. In the present study, the effect of low temperature ($5^{\circ}C$) on pH, titratable acidity (TA), organic acid level, viable microbial cell count, amino acid concentration, and polygalacturonase activity (PG) during long-term fermentation (46 weeks) of kimchi, were evaluated. After 10 weeks of fermentation, kimchi had a pH of 4.1 and a TA of 1.0%, respectively after 46 weeks fermentation, these values were 3.9 and 1.3%, respectively. Lactic acid, the ratio of lactic acid to acetic acid, and the ratio of Lactobacillus species/Leuconostoc species in kimchi increased as fermentation progressed from 10 weeks to 46 weeks. However, total viable cell counts of aerobic bacteria, yeasts, Lactobacillus species, and Leuconostoc species, free amino acid levels, and PG decreased as the fermentation period was extended from 10 weeks to 46 weeks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.30-34
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• 2000

Salted Chinese cabbage was washed in 1,000 ppm solutions of grapefruit seed extract(GFSE) or citric acid, and used to make kimchi for the retentio of quality characteristics during fermentation at $10^{\circ}C$. Kimchi treated with GFSE or citric acid showed a retarded increase in titratable acidity and decrease in pH and reducing sugar content. Total microbial count and lactic acid bacteria of GFSE treated kimchi were about 1.1 log(CFU/g) lower than those of control and citric acid treated kimchi after making, but the difference was gradually reduced during fermentation.

• Journal of Animal Science and Technology
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• v.52 no.3
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• pp.199-204
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• 2010

The objective of this study was to evaluate the effect of the different types and levels of prebiotics on intestinal microflora and fermentation products in the in vitro fermentation model. The prebiotcs used in this study were IMO (iso-malto oligosaccharide), CI (partially digested chicory-inulin), RA (raffinose) and CD (cyclodextrin). Experimental diet for growing pigs was predigested by digestive enzymes and this hydrolyzed diet was mixed with buffer solution containing 5% fresh swine feces. Then, the mixture was fermented with or without prebiotics at the concentrations of 0.5 and 1.0% for 24 h. Samples were taken at 24 h, and viable count of micoflora, gas, pH, volatile organic compounds and short-chain fatty acids were determined. The viable count of Enterobacteriaceae was significantly decreased (p<0.001) in all treatments added with prebiotics in comparison to control without prebiotics. However, the increase of lactic acid bacteria was observed in the prebiotics treatment. Gas production increased as the level of prebiotics increased. The pH values in the fermentation fluid decreased in a dose-dependent manner with increasing the concentration of prebiotics. The fermentation with prebiotics resulted in the reduction of malodorous compounds such as ammonia, hydrogen sulfide, indole and skatole. The increase in short-chain fatty acid (SCFA) production was observed in the treatments with prebiotics. In conclusion, the results of this study demonstrated that the fermentation with prebiotics was effective in reducing the formation of malodorous compounds and increasing lactic acid bacteria and SCFA. These effects depended on the concentration of prebiotics. Moreover, further study is needed to determine whether the in vitro efficacy on the reduction of malodorous compounds and increase of SCFA would also be observed in animals.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.2
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• pp.194-199
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• 2005

This study was conducted to investigate the effect of blanching on the quality characteristics of dandelion Kimchi. Experimental groups were divided BT-group (dandelion was blanched in the $3\%$ brine for 15 seconds at $100^{\circ}C$, then salted in $8\%$ brine for 5 hours) and NT-group (dandelion was salted at $8\%$ brine for 5 hours). Changes in pH, acidity, color, number of total microbe and lactic acid bacteria, antioxidant activity and sensory quality were investigated during the fermentation at $10^{\circ}C$. The pH of the BT- and NT-Kimchi maintained higher than 4.1 for 21-days fermentation, but that of BT-Kimchi was lower than that of NT-Kimchi. And also, the titrable acidity of BT-Kimchi was maintained higher than that of NT-Kimchi. $L^\ast\;value\;and\;b^\ast$ value of BT-Kimchi were higher, while $a^\ast$ value of BT-Kimchi was lower than that of NT-Kimchi. There was no significantly difference in total microbial count between BT- and NT-Kimchi, while number of the lactic acid bacteria in the BT-Kimchi was higher than that of BT-Kimchi. There was no significant difference in the antioxidant activity between BT- and NT-group during the fermentation. In the results of sensory evaluation of the dandelion Kimchi, toughness, color, flavor and overall quality were good in the BT-Kimchi, while the bitter taste showed relatively strong in the NT-Kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.749-755
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• 2014

Exopolysaccharides (EPSs) have been widely used in the food industry as viscofying, stabilizing, and emulsifying agents as well as in the pharmaceutical industry for their immunomodulatory, anti-tumor, and anti-inflammatory effects. A total of 458 lactic acid bacteria (LAB) strains isolated from several kinds of soybean pastes were screened for the production of homo-EPS (HoPS). LAB isolates were primarily screened using thin layer chromatography (TLC) and further screened polymerase chain reaction (PCR) targeting genes involved in HoPS production. Six LAB isolates producing high amounts of HoPS were identified by TLC. Among these isolates, glucansucrase gene was amplified in two strains (JSA57, JSB22), whereas the fructansucrase gene was detected in three strains (JSA57, JSB22, JSB66). After isolating the strains, their morphological characteristics and 16S rDNA sequences were determined. Six species were identified as L. alimentarius HSB15, L. plantarum JSA22, L. pentosus JSA57, L. brevis JSB22, L. alimentarius JSB66, and L. parabrevis JSB89. To evaluate the potential probiotic properties of these LAB, their survival rates against a simulated intestinal environment were determined. After 2 hr of incubation in artificial gastric juice, survival rates of JSA57, JSB90, JSB22, and JSB66 were all greater than 50%. After 2 hr of incubation in bile juice, viable cell count of JSB22 was similar with initial vial cell counts. Growth of the six LAB was screened in arabino-oligosaccharide (AOS)-containing MRS broth. Results showed that growth of the isolates selectively increased after culture in AOS-containing media. Strain JSB22 (6 hr), JSB66 (6 hr), HSB15 (20 hr), and JSA22 (29 hr) showed maximum growth rate. Especially, JSB22 showed the highest growth rate. These results suggest that EPS-producing LAB isolated from Deonjang could be applied as synbiotics.

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.196-203
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• 2006

Three slime-forming lactic acid bacteria were isolated from Kimchi and shown to produce viscous exopolysaccharides (EPS) in sucrose media. The isolated strains, GJ2, C3 and C11, were identified as Leuconostoc kimchii, Leuconostoc citreum and Leuconostoc mesenteroides, respectively, by examining their metabolic characteristics and determining their 16S rDNA sequences. Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 exhibited high viability (maintained initial viable cell count of $10^8$ CFU/ml) in 0.05 M sodium phosphate buffer (pH 3.0) for 2 h, in artificial gastric juice for 2 h and in 0.3% oxgall for 24 h. When tested, Leu. kimchii GJ2, in particular, displayed antimicrobial activity against pathogenic microorganisms. Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 produced 21.49 g/l, 16.46 g/l and 22.98 g/l EPS, respectively, in sucrose (5%) medium. The amount of purified EPS extracted from Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 was 14.61 g/l, 7.73 g/l and 4.77 g/l, respectively. Although the EPS produced by Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 differed in viscosity, TLC and HPLC analysis revealed that each contained only one type of monosaccharide, glucose. The average molecular mass of EPS produced by Leu. kimchii GJ2 was 306,606 Da.