• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.470-478
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• 2017

Objective: This study aims to evaluate the chemical composition, fermentation quality and in vitro ruminal fermentation of various ratios and storage periods of liquid brewer's yeast (LBY) mixed with cassava pulp (CVP). Methods: Four mixtures of fresh LBY and CVP were made (LBY0, LBY10, LBY20, and LBY30 for LBY:CVP at 0:100, 10:90, 20:80, and 30:70, respectively) on a fresh matter basis, in 500 g in plastic bags and stored at 30 to $32^{\circ}C$. After storage, the bags were opened weekly from weeks 0 to 4. Fermentation quality and in vitro gas production (IVGP) were determined, as well as the dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber, acid detergent fiber and acid detergent lignin contents. Results: The contents of CP and EE increased, whereas all other components decreased, in proportion to LBY inclusion (p<0.01). The DM and OM contents gradually decreased in weeks 3 and 4 (p<0.05), while EE contents were lowest in week 0. The pH, ammonia nitrogen per total nitrogen ($NH_3-N/TN$) and V-score in each mixture and storage period demonstrated superior fermentation quality ($pH{\leq}4.2$, $NH_3-N/TN{\leq}12.5%$, and V-score>90%). The pH increased and $NH_3-N/TN$ decreased, with proportionate increases of LBY, whereas the pH decreased and $NH_3-N/TN$ increased, as the storage periods were extended (p<0.01). Although IVGP decreased in proportion to the amount of LBY inclusion (p<0.01), in vitro organic matter digestibility (IVOMD) was unaffected by the mixture ratios. The highest IVGP and IVOMD were observed in week 0 (p<0.01). Conclusion: The inclusion of LBY (as high as 30%) into CVP improves the chemical composition of the mixture, thereby increasing the CP content, while decreasing IVGP, without decreasing fermentation quality and IVOMD. In addition, a preservation period of up to four weeks can guarantee superior fermentation quality in all types of mixtures. Therefore, we recommend limiting the use of CVP as a feed ingredient, given its low nutritional value and improving feed quality with the inclusion of LBY.

• Preventive Nutrition and Food Science
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• v.12 no.4
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• pp.234-241
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• 2007

A physicochemical assessment of Doenjang (traditional fermented soyfood) prepared with Korean black soybeans (Glycine max) was carried out. The T-N rate increased slowly during storage up to 120 days and the A-N rate increased up to 80 days of ripening and then decreased slightly. The caseinolytic activity increased slowly during storage up to 80 days and then decreased after 80 days. In addition, the fibrinolytic and ${\beta}-glucosidase$ activities increased up to 80 and 30 days and then decreased. Genistin and daidzin concentrations gradually decreased with increased fermentation time. However, genistein and daidzein slowly increased with fermentation time. Genistein and daidzein reached maximum concentrations (316.8 and $305.2{\mu}g/g$, respectively) and plateaued thereafter. The anthocyanins increased greatly during fermentation up to 50 days and then remained constant between 50 and 90 days. Polyphenol contents showed a slight increase up to 80 days and then slowly decreased. The DPPH and ABTS radical scavenging activities increased linearly during storage up to 50 days, reached about 28.9% and 2.17 mg/g, respectively, and then slowly decreased. At 20 days of fermentation, macrophage-stimulating activity of the extract showed a maximum activity.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.648-658
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• 2016

Preservation of fresh algae plays an important role in algae seed subculture and aquaculture. The determination and examination of the changes of cell viability, composition, and bacterial species during storage would help to take suitable preservation methods to prolong the preservation time of fresh algae. Nostoc flagelliforme is a kind of edible cyanobacterium with important herbal and dietary values. This article investigated the changes of bacterial species and biochemical characteristics of fresh N. flagelliforme concentrate during natural storage. It was found that the viability of cells decreased along with the storage time. Fourteen bacteria strains in the algae concentrate were identified by PCR-DGGE and were grouped into four phyla, including Cyanobacteria, Firmicutes, Proteobacteria, and Bacteroidetes. Among them, Enterococcus viikkiensis may be a concern in the preservation. Eleven volatile organic compounds were identified from N. flagelliforme cells, in which geosmin could be treated as an indicator of the freshness of N. flagelliforme. The occurrence of indole compound may be an indicator of the degradation of cells.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.44-54
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• 2018

To maintain the best quality of kimchi during long-term storage, we developed a fermentation storage mode for the kimchi refrigerator. The optimal kimchi fermentation temperature was determined to be $6^{\circ}C$ with fermentation time of 4-7 days in winter and 3-5 days in spring and fall. Based on these results, the fermentation storage mode conditions were programmed to consist of a fermentation temperature of $6^{\circ}C$ and fermentation times of 111 h in winter and 58 h in spring/fall. When kimchi was stored under the developed fermentation storage mode conditions, the total acidity of kimchi was almost the same as that of the control kimchi (stored $-2-\;-1^{\circ}C$ for 12 weeks). However, the number of lactic acid bacteria (LAB) and Leuconostoc sp. in kimchi were higher ($10^1-10^2CFU/mL$) than those in the control kimchi during storage. In addition, kimchi fermented and stored under the fermentation storage mode clearly received higher scores for overall preference than the control kimchi.

• Food Science of Animal Resources
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• v.20 no.1
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• pp.21-29
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• 2000

This study was carried out to investigate the fermentation characteristics and storage of set-type yoghurt added mugwort extracts(AME) such as pH, growth of lactic acid bacteria, number of viable cells, viscosity, and sensory characteristics during 24 hours fermentation and 15 days storage. Addition of mugwort extracts was grown rapidly of lactic acid bacteria rather than that of control and also 4 or 8% AME groups were grown similar to control. The drop of AME pH of broth was less compared with control during incubation of lactic acid bacteria. The growth of lactic acid bacteria during incubation of AME yoghurt was not different of viable cell count between AME group and control in beginning time, but the viable cell count of AME groups were increased depended opon addition quantity of AME in ending time. Addition of mugwort extracts was not affect on pH change during yoghurt fermentation and increased a lactic acid bacteria number as well as no effect of yoghurt fermentation in ending time. The viscosity of yoghurt was almost not changed 3 hours after yoghurt mix and increased rapidly 6 hours after yoghurt mix. Although control and 0.5% AME group showed maximum viscosity at 18 hours of fermentation, 1 and 2% AME group showed linear increase until 24 hours of fermentation. Mugwort did not affect pH and viable cel number of lactic acid bacteria during 15 days storage 24 hours after fermentation. Sensory evaluation of the AME yoghurt showed that flavour, texture and acid taste were not affected by addition of mugwort. However, the appearance and taste were dropped by addition of mugwort.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.165-170
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• 2019

The purpose of this study was to analyze the effectiveness of different storage periods of lactic acid bacteria (LAB)-fermented low moisture fresh rice straw silage. The low moisture fresh rice straw sample was inculcated with LAB and stored for different storage periods such as 45, 90, and 365 days, respectively. The low moisture fresh rice straw (LMFRS) silage inoculated with LAB exhibited reduction in pH throughout the fermentation as compared with the control (P<0.05). The lactic acid content was increased at the late fermentation period (90 and 365 days, respectively) in LAB inoculated LMFRS silage as compared with the control (P<0.05). In contrast, the acetic acid and butyric acid concentrations were slightly reduced in the LAB inoculated LMFRS silage sample at 90 and 365 days fermentation, respectively. Meanwhile, the non-inoculated LMFRS silage showed higher amounts of acetic acid and butyric acid at an extended fermentation with low bacterial population as compared with the LAB inoculated LMFRS silage. However, lactic acid concentration was slightly high in the non-inoculated LMFRS silage at early 45 days fermentation. Additionally, the nutrient profile such as crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF), and total digestibility nutrients (TDN) were not significantly different in control and LAB inculcated samples during all fermentation. Though, the microbial population was greater in the LAB inoculated LMFRS silage as compared with the control. However, the massive population was noted in the LAB inoculated LMFRS silage during all fermentation. It indicates that the inoculated LAB is the main reason for increasing fermentation quality in the sample through pH reduction by organic acids production. Overall results suggest that the LAB inoculums are the effective strain that could be a suitable for LMFRS silage fermentation at prolonged days.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.160-167
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• 2019

This study was conducted to investigate the effect of initial ripening condition placed within a kimchi refrigerator and this result will be used as basic data for the development of fermentation system of Kimchi refrigerator. Hardness significantly decreased as the storage period longer. Lactic acid and Lactobacillus spp. showed a large amount until 8 weeks, but one without initial ripening contained much lower. The content of lactic acid bacteria increased from 4.50 logCFU/mL to 6.70 ~ 7.47 logCFU/mL and decreased to 5.08 ~ 6.10 logCFU/mL according to storage period. Consumer preferred $15^{\circ}C/52h$ samples rather than others in two weeks. $15^{\circ}C/36h$ and $6^{\circ}C/113h$ samples were significantly preferred during the whole storage period. These results indicate that the initial fermentation conditions affect the taste and fermentation degree of kimchi during the storage period.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.832-840
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• 2014

This study aimed to investigate the effects of storage duration and temperature on the characteristics of wet brewers grains (WBG) as feeds for ruminant animals. Four storage temperatures ($5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$) and four durations (0, 1, 2, and 3 d) were arranged in a $4{\times}4$ factorial design. Surface spoilage, chemical composition and microorganism density were analyzed. An in vitro gas test was also conducted to determine the pH, ammonia-nitrogen and volatile fatty acid (VFA) concentrations after 24 h incubation. Surface spoilage was apparent at higher temperatures such as $25^{\circ}C$ and $35^{\circ}C$. Nutrients contents decreased concomitantly with prolonged storage times (p<0.01) and increasing temperatures (p<0.01). The amount of yeast and mold increased (p<0.05) with increasing storage times and temperatures. As storage temperature increased, gas production, in vitro disappearance of organic matter, pH, ammonia nitrogen and total VFA from the WBG in the rumen decreased (p<0.01). Our results indicate that lower storage temperature promotes longer beneficial use period. However, when storage temperature exceeds $35^{\circ}C$, WBG should be used within a day to prevent impairment of rumen fermentation in the subtropics such as Southeast China, where the temperature is typically above $35^{\circ}C$ during summer.

• Journal of Microbiology
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• v.42 no.2
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• pp.133-138
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• 2004

This study was aimed to determine the accumulation of free fatty acid by mesophilic lactic acid bac-teria (Lactococcus lactis subsp. lactis 1471, Lactococcus lactis subsp. cremoris 1000 and Lactobacillus casei 111) in cold-stored milk. According to the results, all cold-stored milks had higher acid degree val-ues than those of fresh milk. This phenomenon showed that a slight increase occurred in the accumulation of free fatty acids as a result of spontaneous lipolysis during cold storage. All lactic acid bacteria showed good performance in production of titratable acidity, which increased during fermentation of the milk (fresh and stored milks). Moreover, as the storage time was prolonged, more free fatty acid accumulation was obtained from the fermentation of the cold-stored milk by the investigated lactic acid bacteria. The control milk, which was without lactic acid bacteria, showed no change in the accumulation of free fatty acid during fermentation. From this result, it can be suggested that longer cold-storage time can induce higher free fatty acid accumulation in milk by lactic acid bacteria.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.423-428
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• 2003

Jeungpyun was prepared with varying degrees of fermentation, and their effects on its quality characteristics were examined. In height and volume of jeungpyun, the samples treated with a first fermentation time of 240 minutes, and second and third fermentation times of 60 and 30 minutes, respectively (Sample E) had the best fermentation quality. A texture profile analysis, Hunter's color and sensory evaluation of these jeungpyun were carried out during the 4 days of storage. In the texture profile analysis, the hardness was observed to reduce in proportion to decreases in the fermentation time. The lightness value of Sample E showed one of the highest among the samples, but decreased as the storage time was prolonged. The results of the sensory evaluation showed that Jeungpyun of Sample E had higher swell, softness and moisture scores.