• 한국식품조리과학회지
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• 제13권3호
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• pp.364-368
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• 1997

김치의 비타민 C 함량은 초기값에 비해 증가되었다가 감소하는 것으로 알려져 있어 이에 물김치를 담가 발효, 숙성온도를 달리하여 그 국물에 대하여 pH, 산도, 비타민 C 함량, 총균수, 젖산균수의 변화를 살펴본 결과는 다음과 같다. 3$0^{\circ}C$에서 1일간 숙성시킨 후 비타민 C 함량은 최고에 달해 20 mg% 정도를 나타냈으며, 이때의 pH는 4.5 내외, 산도는 0.2 lactic acid %였고, 미생물균수는 최고 $10^{8}$ CFU/$m\ell$를 나타냈으며 대부분을 젖산균이 차지했다. 이 결과는 그후 온도를 낮춰 15$^{\circ}C$, 4$^{\circ}C$에서 9일간 숙성을 시켜도 차이가 나지않았다. 15$^{\circ}C$에서 발효, 숙성시킨 김치는 최고의 비타민 C 함량인 15 mg%의 비타민 C 함량을 나타낼 때까지 4~5일이 소요되었으며, 이때의 pH는 4.0, 산도는 0.15 lactic acid %였다. 한편 15$^{\circ}C$에서 1일간 발효 후 4$^{\circ}C$에서 숙성시킨 경우에도 이 수준까지 떨어지지 않았다. 4$^{\circ}C$ 발효, 숙성의 경우에는 pH와 산도가 저장 10일 동안 초기값과 크게 달라지지 않았으며, 비타민 C가 증가하지 않아 약 10 mg%에 머물렀다.

• 한국식품영양과학회지
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• 제46권6호
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• pp.744-750
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• 2017

본 연구에서는 240일간 저장한 네 가지 품종의 감자를 Bacillus subtilis로 발효한 후 제조한 감자 칩의 아크릴아마이드 함량과 색도 변화를 알아보고자 하였다. B. subtilis에 의한 단시간 발효는 모든 품종의 감자 슬라이스로부터 유리된 환원당 제거에 효과적이었으나 총당 함량 감소에는 영향을 미치지는 않았다. 또한, 새봉과 진선 감자 슬라이스 내 존재하는 아스파라긴 함량도 감소하였다. 이러한 결과는 복합적으로 감자 칩의 아크릴아마이드 생성량과 색 형성에 영향을 미쳤다. 대서를 제외한 나머지 세 품종은 모두 83% 이상의 아크릴아마이드 감소율을 보였다. 따라서 본 연구는 B. subtilis에 의한 단시간 발효를 통하여 저장감자를 가공식품으로 활용할 수 있는 방안을 제시하고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1528-1539
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• 2019

Objective: To evaluate the effects on microbial diversity and biochemical parameters of gradually increasing temperatures, from $5^{\circ}C$ to $25^{\circ}C$ on corn silage which was previously fermented at ambient or low temperature. Methods: Whole-plant corn silage was fermented in vacuum bag mini-silos at either $10^{\circ}C$ or $20^{\circ}C$ for two months and stored at $5^{\circ}C$ for two months. The mini-silos were then subjected to additional incubation from $5^{\circ}C$ to $25^{\circ}C$ in $5^{\circ}C$ increments. Bacterial and fungal diversity was assessed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiling and biochemical analysis from mini-silos collected at each temperature. Results: A temperature of $10^{\circ}C$ during fermentation restricted silage fermentation compared to fermentation temperature of $20^{\circ}C$. As storage temperature increased from $5^{\circ}C$ to $25^{\circ}C$, little changes occurred in silages fermented at $20^{\circ}C$, in terms of most biochemical parameters as well as bacterial and fungal populations. However, a high number of enterobacteria and yeasts (4 to $5\;log_{10}$ colony forming unit/g fresh materials) were detected at $15^{\circ}C$ and above. PCR-DGGE profile showed that Candida humilis predominated the fungi flora. For silage fermented at $10^{\circ}C$, no significant changes were observed in most silage characteristics when temperature was increased from $5^{\circ}C$ to $20^{\circ}C$. However, above $20^{\circ}C$, silage fermentation resumed as observed from the significantly increased number of lactic acid bacteria colonies, acetic acid content, and the rapid decline in pH and water-soluble carbohydrates concentration. DGGE results showed that Lactobacillus buchneri started to dominate the bacterial flora as temperature increased from $20^{\circ}C$ to $25^{\circ}C$. Conclusion: Temperature during fermentation as well as temperature during storage modulates microorganism population development and fermentation patterns. Silage fermented at $20^{\circ}C$ indicated that these silages should have lower aerobic stability at opening because of better survival of yeasts and enterobacteria.

• Asian-Australasian Journal of Animal Sciences
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• 제27권9호
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• pp.1276-1284
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• 2014

In southeastern regions of the US, herbage systems are primarily based on grazing or hay feeding with low nutritive value warm-season perennial grasses. Nutritious herbage such as annual ryegrass (Lolium multiflorum Lam.) may be more suitable for preserving as baleage for winter feeding even with more intensive production inputs. Emerging in-line wrapped baleage storage systems featuring rapid wrapping and low polyethylene film requirements need to be tested for consistency of storing nutritive value of a range of annual ryegrass herbage. A ryegrass storage trial was conducted with 24-h wilted 'Marshall' annual ryegrass harvested at booting, heading and anthesis stages using three replicated in-line wrapped tubes containing ten round bales per tube. After a six-month storage period, nutritive value changes and fermentation end products differed significantly by harvest stage but not by bale location. Although wilted annual ryegrass exhibited a restricted fermentation across harvest stages characterized by high pH and low fermentation end product concentrations, butyric acid concentrations were less than 1 g/kg dry matter, and lactic acid was the major organic acid in the bales. Mold coverage and bale aroma did not differ substantially with harvest stage or bale location. Booting and heading stage-harvested ryegrass baleage were superior in nutritive value to anthesis stage-harvested herbage. Based on the investigated nutritive value and fermentation characteristics, individual bale location within in-line tubes did not significantly affect preservation quality of ryegrass round bale silages.

• 한국미생물·생명공학회지
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• 제27권3호
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• pp.246-251
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• 1999

To extend the storage period and to inhibit contamination of Kimchi by Escherichia coli, conditions of Kimchi brining and effects of the fermentation starter, halophilic Lactobacillus HL-48 were investigated. Optimum brining condition for Kimchi was accomplished in 15% NaCl and at pH2.5-3.0 adjusted by lactic acid. Starter-treated Kimchi showed pH 4.2 after 18hr fermentation, while the pH of starter-untreated Kimchi resulted in 3.3. After 36hr fermentation, the number of E. coli in starter-treated Kimchi was found clearly to decrease and not detected macroscopically, but contamination of E. coli (5.3$\times$103CFU/ml) was observed in starter-untreated sample. Organic acids in Kimchi contained organic acids such as oxalic acid, citric acid, malic acid and lactic acid. among ther, lactic acid content was remarkably high in the early fermentation stages. However, from 24hr fermentation, lactic acid content of starter-untreated Kimchi was higher than that of starter-treated Kimchi.

• 한국축산시설환경학회지
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• 제14권1호
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• pp.1-8
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• 2008

This study was conducted to solve the problem of public grievance owing to odor of a pig farm. Odor emissions from pig production systems mainly originate from liquid manure storage and solid manure fermentation. The low-cost odor abatement system (OAS) for application at liquid manure storage tank and solid manure fermentation facilities was developed in this study. The OAS adapted odor removing principles of a biofilter and biotrickling filter. The OAS is very simplified in structure. The appearance of the OAS had a form of cylindrical or cubical shape. The system performance was monitored for about one year after stabilization. A 7 seconds empty bed contact time for the OAS was adapted to achieve the odor reduction levels. The commercial type of OAS was constructed with media comprised of wood chips. Moisture content always remained above 50% wet basis. Average ammonia removal efficiency for the developed design was 89% at the liquid manure storage tank. Also, the removal efficiency at a solid manure fermentation facility was 86% on ammonia.

• 한국식품조리과학회지
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• 제11권3호
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• pp.287-294
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• 1995

This study was carried out to determine optimal conditions in storing Andong sikhe. We made Andong sikhe according to the traditional recipe, and fermentation it has been stored either with (group B) or without (group A) "Saengkiwon Songi" for 40 days at 7${\pm}$2$^{\circ}C$. The changes of pHs, sweetness, the number of total bacteria and lactic acid producing bacteria, the quantities of organic acids and free sugars produced had been measured regularly since the 3rd day after fermentation. The results are as follows: The pH of both groups were 5.63 immediately after fermentation, and then gradually decreased to 4.02∼4.05. The sweetness was higher in group A (4.0) until the 15th day of storage, and then the same (17.5) in both groups. The sample from the 6th day in group A, and the samples from the 3rd and the 9th day in group B obtained the highest scores in their sensory evaluation. The numbers of total bacteria and lactic acid producing bacteria showed maxium on the 3rd day in both groups. 8 kinds of organic acids were detected, lactic acid being the most of all. 3 kinds of free sugars - fructose, glucose and maltose - were detected ; glucose and maltose have gradually increased throughout the storage period but fructose was not been detected after the 6th day in both groups.

• Preventive Nutrition and Food Science
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• 제8권3호
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• pp.265-269
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• 2003

Gamma irradiation treatment was performed at the early and mid-fermentation stages of Kimchi preparation. Changes in fermentative microorganisms and lactate dehydrogenase activity during the fermentation periods were investigated to determine proper irradiation point for extending the shelf life of Kimchi. Initial levels of acid producing bacteria and yeast in Kimchi were 10$^4$ CFU g$^{-1}$ and 10$^1$ CFU g$^{-1}$ , and reached up to 10$^{9}$ CFU g$^{-1}$ after 15 days and 10$^{7}$ CFU g$^{-1}$ after fermentation for 30 days at 1$0^{\circ}C$, respectively. The radiation resistance of acid producing bacteria in the earlier stage (D$_{10}$ value was 0.87 kGy) was higher than at the midfermentation stage (after 10 days at 1$0^{\circ}C$, D$_{10}$ value was 0.69 kGy). Microbial growth and lactate dehydrogenase activity were inhibited significantly by gamma irradiation at the early fermentation stage of Kimchi and acidification was effectively delayed during the subsequent storage period. Although the growth of fermentative microorganisms was inhibited by gamma irradiation at the mid-fermentation stage of Kimchi, lactate dehydrogenase activity was maintained and acidification continued during the storage period.

• 한국식품조리과학회지
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• 제26권1호
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• pp.95-103
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• 2010

The objective of this study was to develop a functional vinegar beverage using yacon roots, and examine the components' changes during fermentation. The alcohol fermentation was conducted by inoculation of Saccharomyces cerevisiae into yacon root juice with sugars. After 10 days of fermentation at $27^{\circ}C$, yacon wine contained 13% alcohol and $7.8^{\circ}Brix$ sugar contents. The yacon wine at 5% alcohol was fermented by Acetobacter aceti(KCTC1010) with 250 rpm agitation rate at $29^{\circ}C$ for 12 days. The acidity of yacon vinegar reached 4.4% after 12 days' fermentation. Statistically (p<0.05), the amount of Acetobacter aceti, pH, alcohol, with total polyphenol content of samples decreased with acidity, whereas individual sugar contents increased. Furthermore organic acids, total sugar, phenolic acids content, total antioxidant capacity, and color were not different among the five samples. The yacon vinegar beverage was prepared with high fructose syrup through the dilution of yacon vinegar. After making the yacon vinegar beverage, the pH, acidity, total sugar, and total microbial content were examined every week over 4 weeks' storage. There were no changes in the samples during that time.

• 한국식품영양학회지
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• 제10권3호
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• pp.287-294
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• 1997

When bread making, the condition of thawing-fermentation for frozen dough were tested in variable temperature, and measured thawing-fermentation time and volume of frozen dough. L-Ascorbic acid (L-Aa) was added in frozen dough for the comparison test of develop volume in bread staling degree of baking bread were measured additive frozen dough which was stoppages in freezing, staling degrees were tested hardness with Rheometer. The test for comparison of thawing-fermentation time in variable temperature was shown the condition of dough conditioner at 3$0^{\circ}C$ was most effective for bread making, Because That condition was required very short time(74 min) But, in this comparison of volume in final products was shown the products in the condition of thawing-fermentation at 3$0^{\circ}C$ was smaller than the products at 5$^{\circ}C$(418 ml). The baking volume of L-Aa additive frozen dough which has under gone thawing-fermentation at 3$0^{\circ}C$, were shown baking volume of 420 ml in 2 weeks storage terms to 100 mg/kg L-Aa additive dough and shown baking volume of 454 ml in 4 weeks storage terms to dough of 200 mg/kg additive weight. Staling degrees of L-Aa additive frozen bread were measured with Rheometer. The hardness of 100 mg/kg L-Aa additive frozen bread was sown low level hardness in 1~2 weeks freezing term, 150 mg/kg L-Aa additive frozen bread was shown low level hardness in 3 weeks freezing term. In 4 weeks freezing term, 200 mg/kg L-Aa additive frozen bread was shown low level hardness compared with non-additive L-Aa frozen bread. In comparison of frozen bread quality, non-additive L-Aa products was better than additive L-Aa products in equality of baking shape and external apparence. But in total quality in external and internal apparence, additive L-Aa products was better than non-additive L-Aa products.