• Food Science and Biotechnology
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• 제14권6호
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• pp.722-726
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• 2005

The use of isolated wine yeasts in winemaking processes is preferable to spontaneous fermentation. Selection criteria of wine yeast strains depend also on capacity and rate of fermentation and on alcohologenic capabilities. Our studies have described the dynamics of fermentation of wine musts by some isolated wine yeast strains of Saccharomyces genus: strains 6 and 8 of S. cerevisiae var. ellipsoideus (S. ellipsoideus) and strains 5 and 7 of S. bayanus var. oviformis (S. oviformis). All have high technological properties and all are adapted for the specific pedoclimatic conditions of some areas of Sibiu viticultural region. The selected strains were used as inocula to ferment Sauvignon, Muscat Ottonel, Rose Traminer, and Pino Gris musts in controlled laboratory conditions. It was found that higher initial oxygen concentration in must is necessary to accelerate the fermentation of all the wine yeast strains studied. In order to obtain quality wines, strains with considerable fermentative capacity, high alcohologenic capabilities, and a good conversion efficiency are recommended.

• 한국초지조사료학회지
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• 제15권4호
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• pp.285-290
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• 1995

This experiment was conducted to investigate the effects of wheat bran addition on the fermentative quality and dry matter digestibility(Dh4D) of rye silage. This hexbage was ensiled by the conventional methods in small glass silo of 0.82 liter with addition of wheat bran of 0%, 5%. 01%, and 15%. mpectivery.The samples of rye silage were determined the pH, lactic acid, acetic acid and butyric acid. The DMD was evaluated by pepsin-cellulase technique method. The energy values (total digestible nutrients. TDN : digestible energy, DE : metabolizable energy, ME) were calculated by DMD. The results obtained were as follows : 1. The pH and butyric acid of rye silage were reduced with increasing of wheat bran addition, but the contents of lactic acid and total acid were increased. 2. TDN, DE and ME were increased with high rate of wheat bran addition. 3. Regression equation and correlation coefficients between Flieg's score(X) and DMD(Y) of silage were Y =48.7+0.157X(r=0.917, p<0.01). 4. Regression equation and correlation coefficients between level of wheat bran(X) and Flieg's score(Y) of silage were Y= 18.3+5.56X(r=0.929, p<0.01).

• 한국초지조사료학회지
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• 제11권1호
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• pp.60-67
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• 1991

This experiment was conducted to investigate the effects of starch addition on the fermentative quality and dry matter digestibility(DMD) of Kudzu(Puerari~ thzmbergii Bentham) silage. The herbages was ensiled by the conventional methods in small plastic silo of 7.5 liters with addition of starch of 0 %, 2 %, 4 74, 6 % and 8 %, respectivery. The samples of kudzu silage were separated into leaf and stem, and was determined the pH, organic acid and characteristics of fiber such as neutral detergent fiber(NDF), acid detergent liber(ADF) and acid detergent lignin(ADL). The DMD of leaf and stem silage were evaluated by pepsin-cellulase technique method. The energy values(tota1 digestible nutrients, TDN; digestible energy, DE; metaboliz;~bie energy. ME) were calculated by DMD. The results obtained were as follows: 1. The fiberous meterials(such as NDF, AIIF and ADL) of leaf and stem were decreased with increasing levels of starch(p

• Animal Bioscience
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• 제34권1호
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• pp.56-65
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• 2021

Objective: This study was conducted to investigate the effects of molasses and Lactobacillus plantarum on the ensiling quality and in vitro rumen fermentation of sudangrass silage prepared with or without wilting. Methods: The ensiling experiment, measured with 3 replicates, was carried out according to a 2×4 (wilted stages×additives) factorial treatment structure. Dry matter of the fresh (210 g/kg fresh matter) or wilted (305 g/kg fresh matter) sudangrass were ensiled (packed into 5.0-L plastic jars) without additive (control) or with molasses (M), Lactobacillus plantarum (LP), or molasses + Lactobacillus plantarum (M+LP). After 60 days of ensiling, the silages were analyzed for the chemical, fermentation, and in vitro characteristics. Results: After 60 days of ensiling, the fermentation parameters were affected by wilted, the additives and the interactions of wilted with the additives (p<0.05). The M+LP treatment at wilted had higher lactic acid levels and V-score (p<0.05) but lower pH values and butyric acid concentrations than the other treatments. In comparison with sudangrass before ensiling, after ensiling had lower dry matter and higher non-fibrous carbohydrate. The in vitro gas production, in vitro dry matter digestibility, in vitro crude protein digestibility, and in vitro acid fiber detergent digestibility changed under the effects of the additives. Significant interactions were observed between wilted and the additives in terms of in vitro gas production at 48 h, asymptotic gas production, gas production rate, half time, and the average gas production rate. The total volatile fatty acid levels in the additive treatments were higher than those in the control. Conclusion: Wilting and supplementation with molasses and Lactobacillus plantarum had the ability to improve the ensiling quality and in vitro nutrient digestibility of sudangrass silage. The M+LP treatment at wilted exhibited the strongest positive effects on silage quality and in vitro ruminal fermentation characteristics.

• 식품과학과 산업
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• 제50권2호
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• pp.12-26
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• 2017

Processing steps such as washing and cutting, involved in preparing fresh-cut produce causes tissue damage, leading to rapid quality deterioration. Major defects of fresh-cut produce are discoloration, softening, off-odor development, and microbial growth. Packaging of fresh-cut produce has been changed to reduce these quality problems. Flexible packaging film is widely used to pack fresh-cut produce. Vacuum packaging was the popular packaging method in the beginning of fresh-cut industry in Korea. Vacuum packaging creates high $CO_2$ and low $O_2$ levels to control browning of fresh-cut produce. However, these conditions induce some visual defects and off-odor development. Discoloration problem was also found when fresh-cut produce was packaged with conventional packaging film or plastic tray. Modified atmosphere (MA) packaging is effective for prolonging shelf-life of fresh-cut produce by decreasing $O_2$ and increasing $CO_2$ concentration in the package. Retail MA packaging using different oxygen transmission rate (OTR) film and micro-perforated film has started to be applied to fresh-cut produce in Korea. Proper MA package design that provides optimum range of $O_2$ and $CO_2$ partial pressures is one of the major challenges in the industry. An initial package flushing with $N_2$ or an low $O_2$/high $CO_2$ atmosphere is also used to more rapidly establish steady-state MA condition. Film OTR and $O_2$ flushing affects the fermentative volatile production, off-odor development, electrolyte leakage, discoloration, $CO_2$ injury, microbial population of fresh-cut produce. There is also a demand for convenient packaging to attract consumers. Rigid fresh-cut produce container for retail market has increased since the packaging provides excellent protection from physical damage during transport. Rigid tray used as actual serving vessel for the consumer is increasing in Korea. The tray with flexible lid to wrap or seal fresh-cut produce is more and more gaining popularity. Further practical technology to control quality change and microbial growth for each fresh-cut product has been studied since various fresh-cut items were required. The fresh-cut industry also focuses on searching for more convenient and environmentally friendly packaging.

• Animal Bioscience
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• 제35권8호
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• pp.1162-1173
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• 2022

Objective: This study aimed to investigate the fermentation profiles, bacterial community and predicted metabolic characteristics of Sudangrass (Sorghum sudanense Stapf.) during ensiling. Methods: First-cutting Sudangrass was harvested at the vegetative stage and ensiled in laboratory-scale silos (1 L capacity). Triplicate silos were sampled after 1, 3, 7, 15, 30, and 60 days of ensiling, respectively. The bacterial communities on day 3 and 60 were assessed through high-throughput sequencing technology, and 16S rRNA-gene predicted functional profiles were analyzed according to the Kyoto encyclopedia of genes and genomes using Tax4Fun. Results: The Sudangrass silages showed good fermentation quality, indicated by higher lactic acid contents, and lower pH, butyric acid and ammonia nitrogen contents. The dominant genus Lactococcus on day 3 was replaced by Lactobacillus on day 60. The metabolism of amino acid, energy, cofactors and vitamins was restricted, and metabolism of nucleotide and carbohydrate was promoted after ensiling. The 1-phosphofructokinase and pyruvate kinase of bacterial community seemed to play important roles in stimulating the lactic acid fermentation, and the promotion of arginine deiminase could help lactic acid bacteria to tolerate the acidic environment. Conclusion: High-throughput sequencing technology combined with 16S rRNA gene-predicted functional analyses revealed the differences during the early and late stages of Sudangrass ensiling not only for distinct bacterial community but also for specific functional metabolites. The results could provide a comprehensive insight into bacterial community and metabolic characteristics to further improve the silage quality.

• KSBB Journal
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• 제23권2호
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• pp.118-124
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• 2008

Three kinds of bacteria that influence Kimchi fermentation, Lactobacillus plantarium for acidity, Leuconostoc mesenteroides for ripening Kimchi, and Pichia membranifaciens for decreasing Kimchi quality, were regulated by natural products including Theae folium, Taraxacum coreanum, Brassica juncea, Astragali radix, Gynostemma pentaphyllum, Camellia japonica, Agaricus blazei, and Cordyceps militaris. The common prescription combined T. folium, T. coreanum and C. militaris and simultaneously regulated these 3 bacteria as follows: the growth of L. plantarium and P. membranifaciens were inhibited and L. mesenteroides was promoted. The most effective mixing ratio was T. folium: T. coreanum: C. militaris = 3:2:1. With this new prescription, deep flavor, extended preservation, and a special taste are expected in the Kimchi due to these natural products.

• 한국식품영양과학회지
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• 제30권2호
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• pp.250-255
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• 2001

Effect of molding temperature on the quality changes of extruded meju was studied. Meju was molded at 8$0^{\circ}C$, 6$0^{\circ}C$ and 4$0^{\circ}C$, and then stored at $25^{\circ}C$ with 50% of relative humidity for 30 days. The texture of the cooked soybean grain showed that the firmness and cohesiveness were increased, and consistency was decreased by decrease of molding temperature. The density of the meju molded at 8$0^{\circ}C$, 6$0^{\circ}C$ and 4$0^{\circ}C$ were 1.072g/mL, 1.079g/mL and 1.203g/mL, respectively. The meju molded at 4$0^{\circ}C$ had significantly higher density than those molded at 8$0^{\circ}C$ or 6$0^{\circ}C$. Also, delay of water evaporation, acidification, and rapid growth of fungal mycellium were observed on the sample with molding temperature at 4$0^{\circ}C$ during fermentation. Activity of amylase and protease, contents of total reducing sugar and amino nitrogen of 4$0^{\circ}C$-molded meju were represented lower level than those of 6$0^{\circ}C$ or 8$0^{\circ}C$-molded sample. Therefore, it was considered that the molding temperature was an important factor for meju fermentation and molding temperature of 6$0^{\circ}C$ or over would be acceptable.

• 한국식품조리과학회지
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• 제17권5호
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• pp.431-440
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• 2001

This study was carried out to investigate the effects of oligosaccharide addition on Jeung-Pyun fermentation. Fructooligosaccharide (FOS), isomaltooligosaccharide (IMOS), galactooligosaccharide (GOS) were used at the concentration of 15%, 25% or 35% of the rice in Jeung-Pyun ingredients. The physicochemical properties, sensory evaluation and instrumental characteristics were examined. The internal structure of Jeung-Pyun samples was observed by SEM. The pH of Jeung-Pyun batters was decreased as the fermentation progressed. Compared with the control using sucrose, the specific volume of Jeung-Pyun was higher in the 15% and 25% of oligosaccharide-added samples. The degree of gelatinization decreased more slowly than control as the storage time increased both at 20$\^{C}$ and 4$\^{C}$. In sensory evaluation, Jeung-Pyun with FOS and IMOS at the levels of 25∼35% and GOS at the levels of 25% showed the best scores. In instrumental characteristics, springiness, gumminess, hardness and cohesiveness were similar among all samples during storage at 20$\^{C}$ and 4$\^{C}$. In the internal structure of Jeung-Pyun observed by SEM, Jeung-Pyun substituted with oligosaccharide at the levels of 25% for sucrose showed large and regularly distributed air pores. In conclusion, the replacement of sucrose with oligosaccharide in Jeung-Pyun ingredients appeared acceptable in terms of fermentative aspects.

• 한국식품과학회지
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• 제40권4호
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• pp.400-405
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• 2008

일반적으로 청국장 제조 시 첨가하는 Bacillius subtilis와 기존 청국장에서 분리한 Bacillus sp. Kn-10, 볏짚에서 분리한 Bacillus sp. B-59를 사용하여 청국장을 조제하고 그 청국장의 품질 특성을 비교하였다. 균주에 따른 청국장 발효과정 중 pH와 총 균수는 뚜렷한 차이를 나타내지 않았다. 배양 48시간째 청국장의 점질물량은 Bacillus sp. B-59의 경우 6.28%로 가장 높았으며 , Bacillus sp. Kn-10, B. subtillis 순으로 나타났다. 모든 처리구에서 L 값은 발효가 진행됨에 따라 어두워지는 경향을 보였으며, a 값과 b 값은 감소하는 경향을 나타내었다. 환원당은 발효 24시간까지 증가하였다가 감소하는 경향을 나타내었다. 청국장의 protease 활성도는 Bacillus sp. B-59(117.19 unit), B. subtillis(109.93 unit)는 Bacillus sp. Kn-10(90.97 unit) 보다 우수하였다. B. subtillis 또는 Bacillus, sp. Kn-10 접종구의 DPPH radical 소거능은 증자콩에 비해 감소하였으나 Bacillus sp. B-59 접종구는 발효 기간 동안 증가하였다. 발효 균주에 따른 청국장의 총 아미노산 함량은 Bacillus sp. B-59(34,869.98 mg%), B. subtillis(34,481.89 mg%), Bacillus sp. Kn-10(31,791.09 mg%) 순으로 나타났으며 , Bacillus sp. B-59는 glutamic acid와 lysine 함량이 다른 처리구에 비해 높았다. 관능검사 결과, Bacillus sp. B-59로 제조한 청국장의 색, 맛, 조직감, 종합적기호도에서 가장 양호하였다.