• Proceedings of the Korean Society of Food and Cookery Science Conference
• /
• 1993.05a
• /
• pp.149-159
• /
• 1993

The concept of Solid-State Fermentation is briefly explained in comparison to other fermentation principles, and several types of fermenters are presented. A recently developed "Swing Reactor" for SSF is shown. When inoculated on rice, the mould Monascus purpureus forms red pigments, Which can be used as food colors (Ang-kak, Red Rice). By Response Surface Methodology, serveral factors have been optimized for maximal red colour formation. Showing that presoaking time of rice, pH of soaking water, age of preculture and inoculum size were not of importance within the observed limits. For a fermentation time of 7 days, start humidity is optimal at 34% and temperature is optimal at 28.8 C. These results of small scale fermentation could be transferred to the Swing Reactor.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.3
• /
• pp.554-558
• /
• 1999

Flow properties of traditional kochujang at various fermentation times(0~12 weeks) were determined with rotational cylindrical(RC) and serrated plate plate(PP) viscometer. Magnitudes of consistency index(K) of power law model and Cassson parameters(yield stress and viscosity) measured by PP viscometer were higher than those using RC viscometer. All kochujang samples during fermentation were much shear thinning with values of flow behavior index(n) as low as 0.2~0.34. K value and Casson yield stress measured by PP viscometer had good correlations(r=0.94; r=0.91) with fermentation time. No significant changes in flow model parameters measured by RC viscometer were observed for kochu jang during fermentation. Magnitudes of flow model parameters measured by PP viscometer more closely correlated with fermantation times of kochujang than did RC viscometer.

• Journal of Life Science
• /
• v.11 no.3
• /
• pp.211-217
• /
• 2001

Optimum processing conditions of vinegar using esa tangle extracts were investigated. Sea tangle vineagr was prepared by adding 3% and 5% of glucose, 6% and 10% of ethanol to sea tangle extracts and inoculating acetic acid bacteria. After fermentation for 30 days at 3$0^{\circ}C$, pH was similar to 3.22, 3.21, 3.25 and 3.28 days it was 4.75%, 4.77%, 5.61% and 5.87% respectively. Contents or reducing sugar was 0.70%, 0.70%, 0.88% and 0.89% in initial time of fermentation but it was rapidly decreased by 10 days of fermentation to 0.20%, 0.19%, 0.22%, and 0.21%, respectively. Ethanol contents was 5.88%, 9.77%, 5.75% and 9.68% in initial time of fermentation but it was rapidly decreased by 15 days of fermentation to 1.05%, 1.62%, 0.45% and 1.23%, respectively and it was addition of 5% glucose and 6% ethanol and fermentation for 20 days at 3$0^{\circ}C$. Quality for sea tangle vinegar manufactured using optimum condition were as follows respectively; pH 3.25, acidity 5.38%, total sugar 1.72%, iodine 1,537.2 ppm.

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

• Microbiology and Biotechnology Letters
• /
• v.27 no.4
• /
• pp.333-338
• /
• 1999

This study was aimed to develop a value-added fermented products from rice and apple pomace using Bifidobacterium fermentation. The Bifidobacterium fermentation system of the mixture of rice and apple pomace was developed, and the physicochemical properties of the products were investigated. After 4 different bifidobacteria were compared for their fermentation capability and sensory properties of the fermented product, Bifidobacterium FBD-13 and FBD-22 were selected as appropriate strains for the fermentation of saccharified rice solution(SRS). The optimum inoculation level was 2% and the optimum fermentation time was 42 hrs. When wet apple pomace(WAP) was added to SRS, it contributed to the improvement of sensory properties of the fermented products and the optimum mixing ratio was 40% WAP and 60% SRS in weight. For the fermentation of the mixture of WAP and SRS, Bifidobacterium FBD-27 and FBD-22 were selected as suitable strains.

• Microbiology and Biotechnology Letters
• /
• v.22 no.5
• /
• pp.531-537
• /
• 1994

This study was undertaken with objective of optimizing the conditions of fermentation in an aqueous two-phase system which is composed of polyethylene glycol (PEG) 20000 and crude dextran (Dx). The data were obtained and analyzed using the Box-Wilson's experimental design protocol and the response surface methodology. To reach this end a multilinear polynomial regres- sion model was developed, which can be utilized for the purpose of optimizing the extractive fermentation. Optimum conditions for batch fermentation with aqueous two phase system were found to be at 4.2~5.4% PEG/3.2~4.2% Dx range. The composition of the center was 4.8% PEG/ 3.6% Dx. Optimum operating conditions for initial sugar concentration and fermentation time were approximately 160 g/l, and 21~22 hr, respectively. Fermentation in the aqueous two phase system composed of 5% PEG/4% Dx showed increase of 23% in ethanol concentration, of 9.5% in ethanol yield, and of 19% in ethanol productivity as compared to the case of fermentation of neat Jerusalem artichoke juice.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.4
• /
• pp.699-709
• /
• 2023

This study is to establish optimizing condition of alcohol fermentation in vinegar production with aronia, to confirm whether this can be industrially used, and to compare and analyze a change in anti-oxidative activity and quality characteristic according to alcohol fermentation of aronia. The optimized conditions for alcohol fermentation were as follows: Saccharomyces cerevisiae 5645 of yeast strain, a 5% inoculum size, aronia juice with a brix value of 14, and a glucose content of 7%. As a result to conduct scale up with optimizing conditions of alcohol fermentation of aronia, 8 days (192 hrs) of total alcohol fermentation time and 7.4% of the final alcohol content. The harvest volume accounted for approximately 90.2% with a loss of about 2.8%. As a result of antioxidant test, anti-oxidative activity of alcohol fermented liquor is lower than anti-oxidative activity of aronia extract, because of the decrease of antioxidant by oxidation of the fermentation process. However, the decrease of tannin by the fermentation process reduces acerbity of aronia, so increases overall preference

• Food Science of Animal Resources
• /
• v.33 no.3
• /
• pp.325-330
• /
• 2013

Kefir is traditional fermented milk produced by various lactic acid bacteria (LAB) and yeast, which produce lactic acid, ethanol, carbon dioxide, and other flavor compounds. The purpose of this study was to evaluate the effects of different commercial oligosaccharides, such as maltotriose, fructooligosaccharide (FOS), galactooligosaccharide (GOS), and isomaltooligosaccharide (IMO), on the fermentation properties of kefir. First, we determined the acidification kinetic parameters, such as $V_{max}$, $t_{max}$(h), $t_{pH5.0}$(h), and $t_f$(h) of fermented milk supplemented with 4% (w/w) of different oligosaccharides. The probiotic survival and chemical composition (pH, organic acids profile, and ethanol content) of kefir during fermentation were also measured. Compared to control fermentation, all oligosaccharides increased acidification rate and reduced the time to complete fermentation (pH 4.7). The addition of FOS, in particular, resulted in the lowest $t_f$(h) and the highest populations of LAB and yeast during fermentation. All oligosaccharides increased ethanol production during fermentation. Further, significant differences were observed in the formation rates of six organic acids during fermentation. This study provided comparative data on the properties of commercial oligosaccharides for kefir manufacturing. Consequently, FOS especially had the potential for adequate and effective oligosaccharides in commercial kefir for the improvement of cost- and time-effectiveness.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.6
• /
• pp.1150-1156
• /
• 2017

Understanding phosphorus metabolism in photosynthetic organisms is important as it is closely associated with enhanced crop productivity and pollution management for natural ecosystems (e.g., algal blooming). Accordingly, we exploited highly time-resolved metabolic responses to different levels of phosphate deprivation in Chlamydomonas reinhardtii, a photosynthetic model organism. We conducted non-targeted primary metabolite profiling using gas-chromatography time-of-flight mass spectrometric analysis. Primarily, we systematically identified main contributors to degree-wise responses corresponding to the levels of phosphate deprivation. Additionally, we systematically characterized the metabolite sets specific to different phosphate conditions and their interactions with culture time. Among them were various types of fatty acids that were most dynamically modulated by the phosphate availability and culture time in addition to phosphorylated compounds.

• Journal of the Korean Society of Food Culture
• /
• v.35 no.5
• /
• pp.450-458
• /
• 2020

This study examined the optimal temperature and time conditions to maintain high quality Dongchimi during the fermentation and storage period. Dongchimi was fermented at low (5℃), medium (10 and 15℃), and high (20℃) temperatures until the acidity reached 0.2, 0.3, and 0.4%. respectively. From the consumer's preference test enrolling five consumers, Dongchimi fermented at 15℃ until an acidity of 0.3% (for approximately six days) was evaluated to be the optimal status because of its high score of overall acceptance, taste, and odor of consumers. To determine the optimal storage temperature of fermentation, Dongchimi was stored at three different temperatures (-1, 2, 5℃) for four weeks after fermenting at 15℃ for six days. During the storage period, most of the physicochemical properties (pH, acidity, reducing sugar content, and organic acid) and microbiological properties changed significantly in the 2 and 5℃ groups, resulting in a significant change in descriptive sensory analysis of Dongchimi. These results indicate that fermentation at 15℃ and storage at -1℃ for Dongchimi enables it to maintain the best quality for a long time.