• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.864-868
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• 1998

The studies were carried out to investigate the mixed effects of medicinal herbs, such as Lithospermum erythrorhizon and Glycyrrhiza uralensis(LG), and LG with chitosan(LGC) on shelf-life of kimchi fermented at 1$0^{\circ}C$ for 25 days. During the fermentation, pH was more slowly lowered in LG(1%, 3%) and LGC treatments than in control. Titratable acidity of these treatments was slightly lower than that of control. Viable cells of total bacteria and lactic acid bacteria in kimchi added with LG(3%) and LGC showed inhibitory effects about 1.2~1.6, 1.3~1.8 log10 cycle. The sour taste of kimchi added with LG or LGC was changed more slowly than that of control during fermentation for 5 days at 1$0^{\circ}C$. But flavor, color and overall acceptability did not show significant differences(p<0.05) among treatments. The color of kimchi added with LG was improved significantly by adding of 1% chitosan. The shelf-life of kimchi added with LGC was extended about 10 days than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.218-223
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• 2000

The objective of this study was to investigate the effectiveness of preservatives for extending storage life and maintaining the quality of minimally processed Chinese cabbage. Cut Chinese cabbage was treated with either 1% CaCl2, 1% NaCl, 3% sucrose, 1% Ca-lactate, 1% vitamin C, 0.05% chitosan＋1% vitamin C, 0.1% Sporix＋1% vitamin C or hot water(6$0^{\circ}C$) and then packed with polyethylene film(60${\mu}{\textrm}{m}$) and stored at either 2$0^{\circ}C$ or 4$^{\circ}C$. To evaluate biochemical changes and quality of minimally processed Chinese cabbage, the samples were tested to determine the amount of vitamen C, titratable acidity, organic acid and fiber contents. Changes in color were also examined. The quality of kimchi prepared form minimally processed cabbage was affected by the treatments. REsults indicate that the minimally processed Chinese cabbage treated with either 1% CaCl2 at 2$0^{\circ}C$ and 4$^{\circ}C$ or 1% NaCl at 2$0^{\circ}C$ minimized biochemical changes in plant tissue and those treatments were most effective in maintaining product quality. The cabbage treated with 1% vitamin C or 1% NaCl at 4$^{\circ}C$ resulted in kimchi with improved color, texture, flavor and the best overall acceptability, as determined by a sensory test.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1077-1085
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• 1997

This study was carried out to elucidate the utilization of the fusant for shortening the ripening time by making an observation of the microstructure and the profile of component change. In ripening cheese, moisture content of the sample treated with tested strain is not a remarkable difference among the test samples. With an increase of the ripening time, L. helveticus showed the highest increase in protein content, followed by fusant, and then L. bulgaricus. The fat content of all starters was gradually decreased while it was it was rapidly decreased after 7 days. The pH of all starters was gradually decreased when the ripening time increased. The titratable acidity was greatly increased between a 9th day and a 15th day ripening. In investigating the light microscopic microstructure of ripened cheese samples, the sample treated with fusant indicated little difference from the other starters in decomposition of protein and fat components by microbial enzymes. In SEM observation, the structure of all cheese samples was uniform and the rough texture was converted into smooth texture by the interaction of cheese components and the abscission of single bond in casein matrix when the ripening time is increased. The fusant showed similar results in the examination of component change and its microstructure compared with the other starters. Therefore, it was revealed that the fusant can be partially used as a cheese starter instead of conventional starters by replacing them or combining them together with the other starters for shortening the ripening time.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.780-787
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• 2023

Two mannitol producing lactic acid bacteria were isolated from pa (green onion)- kimchi, identified and named as Leuconostoc mesenteroides SKP 88 and Leuconostoc citreum SKP 92, respectively. Both isolates grew well at 25-30℃, initial pH 6-8, and 3% and lower NaCl concentration. Both isolates converted fructose into mannitol efficiently when grown on MRS broth containing fructose and glucose. Glucose was used as a carbon source and fructose was used as a precursor for mannitol. Mannitol yields were the highest in MRS broth with 3% fructose and 2% glucose. Shine muscat juice fermentation was done using each isolate as a starter. As fermentation progressed, decrease in pH and increases in titratable acidity and viable counts were observed. L. mesenteroides SKP 88 showed better mannitol conversion ability than L. citreum SKP 92, and shine muscat juice fermented with L. mesenteroides SKP 88 showed the mannitol production of 41.6 g/l at 48 h, and juice fermented with L. citreum SKP 92 showed 23.4 g/l at the same time. Yogurt fermentations showed similar patterns, and yogurt fermented with L. mesenteroides SKP 88 showed the mannitol production of 15.13 g/l. These results showed that both strains are useful as starters for healthy fermented foods with reduced fructose contents.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.270-277
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• 2003

In order to enhance the firmness and shelf-life of kimchi, as well as to increase the content of well-absorbed digestible calcium, the effect of calcium lactate (CaL) treatment of salted Chinese cabbage on pH, tit ratable acidity, total microbes, lactic acid bacteria, alcohol insoluble substance (AIS) content, firmness, mineral content and tissue structure were investigated. Treatment with the Cal solution increased pH and decreased titratable acidity, which was more pronounced at higher concentrations. The edible period evaluated by pH was 7～8 days for non-treated kimchi, 10 days for 1 % treated kimchi, 15 days for 2% treated kimchi and 20 days for 3% treated kimchi. Total microbes were reduced, but lactic acid bacteria counts were higher in the treated group. CaL treated kimchi showed higher AIS content and firmer texture, which was more conspicuous in the 2 and 3% CaL treated groups. Calcium content in kimchi fermented for 15 days was 40.75～41.53 mg%, which is 42～45% higher than that in the control group. The sodium content was 23～54% less in the treated groups. The epidermis and vascular bundle tissue of kimchi fermented for 15 day was damaged more severely in the control group than in the treated group. CaL treated kimchi has a crispier taste and the development of sour taste was delayed. Therefore, addition of CaL can produces a kimchi with high calcium as well as superior texture and shelf-life, when adjusting the concentration according to the fermentation periods.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.205-210
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• 2015

The objective of this study was to develop yogurt-cheese using cow’s milk, ultrafiltrated cow’s milk, and soy milk. The addition of soy milk and ultrafiltrated milk increased the amount of protein in the yogurt-cheese. Yogurt-cheeses were made using cheese base using 10% and 20% soy milk with raw and ultrafiltrated cow’s milk, and stored at 4°C during 2 wk. The yield of yogurt-cheeses made with added soy milk was decreased and the cutting point was delayed compared to yogurt-cheese made without soy milk. Yogurt-cheese made using ultrafiltrated cow’s milk showed the highest yield. However, yogurt-cheese made with added soy milk had higher protein content and titratable acidity than yogurt-cheese made using raw and ultrafiltrated cow’s milk. Fat and lactose contents in the yogurt-cheese made with added soy milk were lower. Yogurt-cheeses made with added soy milk contained several soy protein bands corresponding to the sizes of α₂-, β-, and κ-casein band. Yogurt-cheese made with added soy milk had similar elasticity to yogurt-cheese made without soy milk but had lower cohesiveness. There was no significant difference in the number of lactic acid bacteria in the different cheeses, as all had over 8.0 Log CFU/g. Considering these data and the fact that proteins and fats of vegetable origin with high biological value were observed as well as unsaturated fats, yogurt-cheese made with added soy milk can be considered to be a functional food.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.421-426
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• 1994

This study was carried out to investigate the effect of $CaCO_3$ on the Chungkookjang Meju fermentation. B. subtilis was cultured on the Meju added 0, 0.01, 0.1, 1% $CaCO_3$, respectively, and the chemical composition, protease activity, amino acid and vitamin B complex were examined with fermentation time. The inner temperature of the $CaCO_3$ treatments during fermentation was increased as compared with the control group. Titratable acidity in Meju decreased as $CaCO_3$ concentration increased. And protease activity and amino-nitrogen content were however high in same order. The content of amino acid was on the increase in every treatments, it made no difference between $CaCO_3$, treatments and the control. Vitamin B complex content in the $CaCO_3$ treatments was increased than in the control. The 0.01% added treatment showed the highest amount of vitamin B complex content in all the treatments.

• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.83-88
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• 1990

This experiment was conducted to investigate the effect of $CO_2$ treatment on quality of strawberry during storage. Gas composition in polyethylene(P.E.) film bag during storage was changed markedly at early stage of storage and then kept at the level of 8-9% $CO_2$and 1-2% $O_2$. Weight loss and decay were restricted by $CO_2$ pretreatment and P.E. film packaging. Titratable acidity, PH and soluble solids were not changed greatly during storage. Firmness of flesh was increased by $CO_2$ treatment till 14 days of storage and decrease of a value reduced by $CO_2$ treatment and P.E.film packaging, too. Ascorbic acid contents were more high in not packed samples than packed untill 14 days of storage but after that those were more high in P.E.film packed and $CO_2$ treated samples.

• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.270-281
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• 2006

The study investigated the effect of prefermentation of Bifidobacteria longum and Lactobacillus plantarum on baking quality. Firstly, two kinds of prefermentation were cultured using two lactic acid bacteria, Bifidobacteria longum and Lactobacillus plantarum. White pan bread baked with dough that had undergone these two prefermentation methods was compared with that baked with a non-prefermented control. The physicochemical properties of the three breads were analyzed, and then the physicochemical and sensory properties of the dough and baked bread were cross-analyzed. The pH prefermentation of Bifidobacteria longum was lower than that of Lactobacillus plantarum, whereas the titratable acidity was higher. Compared to the results from analyzing the prefermentation of Lactobacillus plantarum, the prefermentation of Bifidobacteria longum was expected to give positive effects on enriching the bread flavor by creating acetic acid at a level three- to eight-fold higher than that of Lactobacillus plantarum. According to the mixogram data, the optimum ending time for both Bifidobacteria longum prefermentation and Lactobacillus plantarum was around 4.5 to 5 minutes. The speed of dough materialization decreased with increasing prefermentation culture time. The baked bread with added Bifidobacteria longum had a higher water content. However, the other contents were not influenced by prefermentation, but were by culture time. The specific loaf volume, oven spring and baking lass rate all peaked at 20 hours after culture for both prefermentation cultures. The sensory test results indicated the highest prefermentation for the bread baked with prefermented Bifidobacteria longum doughwith a culture time ranging from 20 to 26 hours. In addition, the bread baked with prefermented Lactobacillus plantarum dough gave the highest preference when cultured for 20 hours.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.267-274
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• 2013

Demand for a rice cake, a popular traditional food in Korea, is rising, but its industrial-scale production is extremely difficult due to its short shelf-life caused by starch retrogradation and microbial spoilage. By means of the sourdough fermentation technique, we attempt to develop rice cakes with a longer shelf-life. Heterofermentative lactic acid bacteria (Weissella koreensis HO20, Weissella kimchii HO22) isolated from kimchi were used to ferment wet-milled rice flour for their abilities to produce exopolysaccharides and to inhibit the microbial spoilage of rice cakes. After 24 hr of fermentation at $25^{\circ}C$, viable cell counts in rice dough increased from $10^6$ CFU/g to $10^8$ CFU/g and total titratable acidity increased from 0.05% to 0.20%, whereas pH decreased from 6.5 to 5.1. Fermented rice flour showed significantly lower peak, trough, and final viscosities as well as breakdown and setback viscosities measured by rapid viscoanalyzer. Both lactic acid bacteria showed in vitro antifungal activity against Penicillium crustosum isolated from rice cakes. The antifungal activity remained constant after the treatments with heat, proteinase K and trypsin, but fell significantly by increase of pH. Rice cakes made of fermented rice flour were found to retard mycelial growth of P. crustosum. The degree of retrogradation as measured by the hardness of the rice cake was significantly reduced by the use of fermented rice flour. The results suggest that use of fermented rice flour has a beneficial role in retarding starch retrogradation and in preventing fungal growth, hence extending the shelf-life of rice cakes.