• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.519-519
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• 2013

본 연구에서는, 전기적 충격이 없고 넓은 면적을 동시에 처리할 수 있는 형태의 유전체 장벽 방전(DBD: Dielectric Barrier Discharge)을 이용한 대기압 저온 플라즈마 장치를 제작하고 이를 이용하여 빵 곰팡이(Neurospora crassa) 살균에 대한 기본 분석을 하였다. 실험에 사용한 저온 대기압 면방전 플라즈마의 파워는 사인파 교류전압을 인가하여, 방전전압은 1.4~2.3 kV, 방전전류는 20~30 mA의 값을 가지며, 전압과 전류의 위상차는 약 80도의 기울기 차이가 난다. 이때의 출력은 약 4 W를 가지며, 공랭식 쿨러를 이용하여 유전체의 열을 배출하였다. 시료대의 온도 측정결과 방전과 동시에 쿨러를 작동할 경우 최대 10분에서 37도를 넘지 않았다. 장치에서 발생하는 플라즈마에 의한 O3의 양은 플라즈마 발생부로부터 10 mm 이내에서 약 25~30 ppm 이 측정되었으며, NO나 NO2 는 거의 검지되지 않았다. 증류수(Deionized water)속에 담긴 빵 곰팡이(Neurospora crassa) 포자를 면방전 플라즈마 발생장치로 처리하였을 때, 포자의 발아율은 처리시간 및 출력파워가 증가함에 따라 급격히 감소하였으나 VM (Vogel's Minimal) 배양액에 넣고 플라즈마 처리를 한 경우에는, 증류수의 결과와 달리 살균효과가 미비함을 보였다. MTT 측정법 또한 같은 경향성을 보였으며, 이를 통해 포자를 둘러싸고 있는 환경이 플라즈마의 살균효과에 영향을 미치는 것으로 보인다. 본 실험을 통해, 유전체 장벽을 이용한 면방전 플라즈마 발생장치가 플라즈마 제트(jet)와 달리 직접적인 플라즈마 접촉 없이도 미생물 살균이 가능하다는 것을 보았으며, 처리대상의 생체용액과 같은 주변 환경에 영향을 받음을 알 수 있었다. 또한 면방전 플라즈마 장치로부터 발생하는 O3과 같은 활성종들이 빵 곰팡이의 비활성화에도 역할을 할 수 있음을 알 수 있었다.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.643-648
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• 2008

The principal objective of this study was to evaluate the effects of the addition of sourdough to bread dough, specifically with regard to the physicochemical characteristics of bread dough, organoleptic evaluation, and bread storage. Marked increases in lactic acid bacterial counts $10^{9-10}CFU/g$ in dough samples with 30, 50, and 100% of added sourdough to the respective bread dough were observed after the first fermentation period of the dough, but decreases were observed in yeast cells. The highest overall acceptance scores were recorded for the 100% sourdough-added bread, and almost no differences in taste and texture were detected between the regular bread (control bread) and sourdough-added bread on the sensory evaluations, with slightly lower evaluation scores (for sour taste) in the sourdough-added bread. The sourdoughadded bread also showed retarded mold growth in the bread on our storage tests. Six days had elapsed prior to the appearance of mold growth in the sourdough-added bread, whereas three days elapsed in the regular bread. The more sourdough was added to the dough, the less was the total count in bread. Increases of 13.1, 20.9, and 36.2% in the retardation of starch retrogradation of the bread were observed as the result of additional increases in sourdough quantity to bread at 30, 50, and 100%, respectively.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.430-436
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• 2003

Coating treatment with 120 kDa of chitosan on bread was decreased growth rate of bacteria and not detected growth of any fungi during storage period. Bread with coating by 1% and 2% of 120 kDa chitosan have had the high antioxidant. Change in the water content was lawered as the higher concentration of chitosan coating on bread. water activity has a low variance untill 2% of chitosan concentration and so there result are expected on inhibition effect of retrogradation in bread during storage period. The change of pH was not detected in bread. And the color of bread have not effected on treatment with below 2% of chitosan but had a little effect by 2% of chitosan coating.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.539-545
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• 2003

The physiological and sensory properties of breads, prepared with wheat flour substituted with various herbs, were evaluated. The specific gravities and maximum heights of the breads increased when the wheat flour was supplemented with 1% rosemary, lemon balm or lavender, and with 3% rosemary, but not with 3% lemon balm or lavender. The fermentation and cooling losses of the breads with added herbs were smaller than those of the control, but there was no significant difference in the baking loss. The lightness of the breads decreased with increases in the herb contents. In the texture measurements for the breads, the hardness decreased slightly on the addition of 1% of the herb powders, but increased on the addition of 3% of the herb powders. As for the results of the sensory evaluation, the overall acceptances of the breads with 3% added herbs were higher than those of the control and 1% added herb breads. The addition of herbs to the breads inhibited the growth on fungi, and the more herbs substituted, the higher the degrees of this inhibition. The moisture contents were slightly increased, and the staling rates during storage at 25 decreased, in breads with added herbs. These results suggest that the shelf-lives of the breads were extended by the addition of herbs.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.2
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• pp.136-144
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• 2003

This study was conducted to investigate the effect of 0.5% calcium lactate(CaL) on the fermentation of dough and quality and shelf-life of bread. Calcium lactates(CaL-A and CaL-P) were prepared from ash of black snail which contained shell and tissue together(ABS) and powder of the snail(PSB). pH of dough with the CaLs were higher than that of the control md, volume of the dough, loaf volume of bread were lower than those of the control products. But the volumes were almost the same when the pH of the dough were adjusted to pH 5.5. Mean calcium contents of treated bread (39.36~49.70 mg/100 g) were higher than that of control products(13.43 mg/100 g). There was no difference in Hunter $L^{*}$, $a^{*}$, $b^{*}$ values between the control and the treated group. Hardness and gumminess of CaL-A treated bread were the highest, but springiness and cohesiveness were the lowest. All the attributes showed no difference in case of pH adjustment(pH 5.5). The smaller pore and larger air cell with rough surface were observed in the CaL treated bread by SEM analysis. Sensory scores of CaL treated bread showed relatively lower values than those of the control products, but the scores increased by pH adjustment. The shelf-life of bread with CaL-P and CaL-A at 2$0^{\circ}C$ were 4 and 3 days, respectively, while that of the control group 1 day.day.y.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.121.2-122
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• 2003

다슬기분말(PSB)과 그 회분(ASB)으로 제조한 칼슘락테이트(PCaL 및 ACaL)를 0.5%씩 첨가한 반죽의 발효와 빵의 품질 및 저장성에 미치는 영향을 조사하였다. 반죽의 pH는 4.85~4.98로 ACaL.PCaL.대조군의 순으로 나타났다. 반죽의 부피와 빵의 loaf volume index는 대조군이 높았고 ACaL 첨가군이 낮았으며, pH를 5.50으로 조정하여 제조한 반죽의 부피와 빵의 loaf volume은 대조군과 큰 차이를 보이지 않았다. PCaL 및 ACaL을 첨가한 빵의 Ca함량은 29.4~29.7 mg/100 g-f.w로 대조군의 13.0 mg/100 g-f.w에 비하여 높았으며, 첨가군의 미량 무기질로 Mg, Fe, Zn이 0.03~0.98 mg/100 g-f.w 범위로 검출되었다. 빵의 L$^{*}$ 값은 대조군과 실험군의 유의적인 차이가 없었으며, a＊값, b＊값은 PCaL 첨가군이 가장 높아 황갈색을 띄었다. 빵의 hardness, gumminess는 대조군$^{\circ}C$ 실온에 두면서 저장한 결과 대조군은 3일째부터, ACaL 첨가군은 5일째부터, PCaL 첨가군은 6일째부터 곰팡이가 번식하였다.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.6
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• pp.608-614
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• 2003

This study was conducted to investigate the quality characteristic of bread added with 0, 2, 4 and 8% liquid calcium acetate(LCA-breads) to the dough prepared with brown rice, vinegar and ash of black snail replacing wheat flour. The pH of the dough was 5.38 in control and 5.39∼5.42 in the LCA-broads, which showed that the higher the content of LCA, the higher the pH. There was no big difference of the baking loss between control (10.73%) and LCA-breads(10.11∼10.81%). The loaf volume index was 7.12 in the control, 7.18 in the 2% LCA-bread, while the index was 6.22 in the 4% LCA-bread, 5.80 in the 8% LCA-bread. Calcium content was 16 mg% in the control, 30, 60 and 120 mg% in 2, 4 and 8% LCA-bread, respectively. The hardness, gumminess and brittleness of LCA-breads were higher, while springiness and cohesiveness were lower than that of the control. In the LCA-breads, $L^{*}$ values were lower and $b^{*}$ value was higher than those of the control, while there were no significant difference in af values. Increasing the LCA, air cells were bigger and irregular, and starch matrix was unstable. There were no significant difference in sour and bitter taste. The scores of stickiness of the 2∼4% LCA-breads were similar to that of the control and higher in the 8% LCA-bread. The scores of the flavor and overall taste in the LCA-breads were similar to the control, while the values were lower in the 4∼8% LCA-breads. The shelf-life evaluated by the number of moldy spots was not different between the control and 2% LCA-bread, while it was extended two times in 4% and three times in the 8% LCA-bread.ead.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.413-417
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• 2003

To evaluate the antimicrobial activity of green tea against putrefactive microorganism in steamed bread, antibacterial activity of green tea extract against well-known strains of spoilage bacteria (Bacillus subtilis ATCC 6633, Bacillus pulmilus KCTC 3348 and Bacillus cereus IFO 12113) and mold (Aspergillus niger KCCM l1239) in bread was determined using the paper disk method. The green tea extract (GTE) showed the inhibition effects on the growth of all the strains of bacteria and mold at 1, 2, 3% levels. The activity of GTE was stable in the wide range of pH (4~9) and temperature (50~20$0^{\circ}C$). When green tea powder (GTP: 1, 3, 5%) was added to steamed bread increase of total bacterial and mold counts declined during storage at 25"C as the levels of GTP increased. By addition of 5% GTP, mold appeared 1 day late extending shelf life of steamed bread compared to control bread without GTP. Therefore, the levels of GTP added to steamed bread could be more than 5% for extended shelf life and wholesomeness of steamed bread.read.

• Food Science and Preservation
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• v.12 no.6
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• pp.583-590
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• 2005

Dough fermentation characteristics and quality characteristics of bread added with different concentration(0, 30, 40 and $50\%$ against water) of submerged-culture broth of Fomitopsis pinicola mycelium (CM) were investigated There were positive correlations between CM concentration and dough pH(r=0.98), acidity(r=-0.88), dough thickness(r=0.95) and dough strength(r=0.95). Baking loss rate was decreased with increasing of CM concentration. There was no significant difference between loaf volume index and CM concentration ($30\~40\%$, but the index of CM $50\%$ bread was lower than that of control. L* value of top crust in the CM $50\%$ bread was significantly lower than those of CM $0\~40\%$ bread, while the value of internal tissue was increased with increasing of CM concentration. In the CM $30\~40\%$ bread, hardness was lower, but there were no significant difference in cohesiveness, springiness, chewiness and brittleness compared with control. Appearance, color, taste, texture and overall acceptability of CM $30\~40\%$ bread were similar to those of control. In the results estimated by correlation analysis, the increased pH of the dough by adding CM allowed lowering hardness of the bread By adding CM in bread, retrogradations were delayed, and growth of mold was decreased during storage. In conclusion, the optimum concentration of CM in bread which showed anti-diabetic effect as well as not dropped quality characteristics were $30\~40\%$.

• Korean Journal of Microbiology
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• v.13 no.2
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• pp.45-50
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• 1975

Uptake of $^{14}C$-sorbose and $^{14}C$-3-O-methylglucose by ungerminated conidia of Neurospora crassa was measured by means of the millipore filter technique. Initial rates of jptake of both sorbose and 3-O-methylglucose show a marked dependence optimal pH for uptake of both sugars is close to 4.75. When ungerminated conidia are "starved" with buffer for a prolonged period of time prior to assaying their transport capacity and mycelia, no de-repression of the glucose-repressible sugar transport system is effectuated in contrast to the findings for germinated conidia.d conidia.