• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.203-204
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• 2003

Change in Quality Properties of Doenjang Prepared with the Powder of Paecilomyces japonica and extract of P. japonica by different solvents were investigated during 90 days of fermentation at 20$^{\circ}C$. The moisture content was not significantly different, pH of Doenjang made with P. japonica was lower than control group and decreased continuously according to the fermentation time. Amino nitrogen continuously increased till 60 days and decreased slightly on 90 days. Value of L, a, b in Color decreased with proportion to fermentation period and L, a, b value of Doenjang made with P. japonica was lower and in Particular that of Doenjang made with P. japonica powder was lowest. From the result of sensory evaluation test, the color of control group was similar to “yellow”but that of Doenjang made with powder of P. japonica was close to“dark brown”and that of Doenjang made with extract of P. japonica was darker than that of control group and the preference of dark color was low. Texture was“glossy and smooth”in all and preference was high. In salty taste, Doenjang by P. japonica addition was stronger and Doenjang made with extract was stronger than that made with powder. Doenjang made with powder of P. japonica was weaker than other groups in sweet taste. In flavor and overall Preference, Doenjang made with P. japonica was scored lower slightly in than control group and Doenjang made with powder of P. japonica was the lowest in score.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.204-205
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• 2003

Change in Quality properties of the Kochujang Prepared with the powder of Paecilomyces japonica and extract of p. japonica by different solvents were investigated during 90 days of fermentation at 20$^{\circ}C$. The moisture content was not significantly different, pH of Kochuiang made with p. japonica was lower than control group and decreased continuously according to the fermentation time. Amino nitrogen continuously increased till 60 days and decreased slightly on 90 days. Amino nitrogen of Kochujang made with P. japonica was higher than control group and was highest on 30 days and 60 days by 179.2mg% and 282.2mg% respectively. Value of L, a, b in Color decreased with proportion to fermentation period and L, a, b value of Kochujang made with P. japonica was lower and in particular that of Kochujang made with P. japonica powder was lowest. from the result of sensory evaluation test, the color of control group was similar to“clear red”but that of Kochojang made with powder of P. japonica was close to“dark reddish brown”and that of Kochujang made with extract of P. japonica was darker than that of control group and the preference of dark color was low. Texture was“glossy and smooth”in all and preference was high. In salty taste, the Kochujang by P. japonica addition was stronger and Kochujang made with extract was stronger than that made with powder. In hot taste, the Kochujang made with P. japonica was weaker than control group and the Kochujang made with P. japonica was scored higher in flavor than control group and Kochujang made with powder of P. japonica was the highest in score. In overall preference, the Kochujang made with P. japonica was better than control group like the result of flavor but expecially Kochujang made with water extract of P. japonica among the extract was best one unlike the result of flavor.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.694-700
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• 2003

Changes in the Qualify Properties of Doenjang Prepared using the Powder or extracts of Paecilomyces japonica were investigated during fermentation at 20$^{\circ}C$. The moisture content was increased during fermentation but was not significantly different in all treatments. The pH of Doenjang with p. japonica was lower than the control group and decreased with the fermentation time. The amino nitrogen content increased gradually for up to 60 days and decreased slightly at 90 days. The L, a and b value decreased in proportion to the fermentation period and those of Doenjang with P. japonica powder were the lowest. From the results of the sensory evaluation, the color of the control group was similar to "yellow" but that of the Doenjang made from powder of P. japonica was close to "dark brown" and those of the Doenjang made from the P. japonica extract were darker than that of the control group. The texture was "glossy and smooth" in all cases and preference about the texture was high. The Doenjang with added P. japonica Powder had a saltier taste and the Doenjang with P. japonica Powder had the least sweet taste. In the flavor and overall Preference, the Doenjang with P. japonica powder was the lowest.

• Journal of Energy Engineering
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• v.15 no.2 s.46
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• pp.118-126
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• 2006

This publication provides an overview of the state-of-the-art and perspective of biological $H_2$ production from water and/or organic substances. The biological $H_2$ production processes, being explored in fundamental and applied researches, are direct and indirect biophotolysis from water, photo-fermentation, dark anaerobic fermentation and in vitro $H_2$ production. The development of biological $H_2$ production technology, as an energy carrier, started at the late 1940's in the lab-scale. Now it has a high priority in the world, especially USA, Japan, EU and Korea.

• KSBB Journal
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• v.6 no.3
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• pp.299-307
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• 1991

In this paper the effect of light on non-aerated Baker's Yeast(Saccharomyces cereuisiae) production and the protein excretion to the extracellular fluid is studied. Previous results in our laboratory indicate that at pH=5 and T-32$^{\circ}C$ yeast may be affected by light, but those differences seem to be within statistical variation of the data. In this paper, cell and extracellular protein concentrations along with redox potential are monitored for batch fermentations in the presence and absence of light at pH levels of 3 and 5 and at 31$^{\circ}C$, in order to explore whether possible light effects can be more readily discerned at lower pH values. Yeast particle size distributions are also determined over the course of fermentation using a particle counter in order to add one more measuring tool to our usual cell and total protein measurements. An apparently noticeable difference in the redox potential is observed between the light and the dark runs for early times for the pH=3 runs. The particle size distributions show differences in the particle diameters between light and dark runs at pH=3, but those differences fall within one standard deviation of the mean particle diameters.

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.46-50
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• 1993

In 12:12 hour light/dark cycle cultivation of D. salina 1650, maximum specific growth rate of 0.59 (l/day) and 0.35 (g-crude hydrocarbons/l/day) were obtained. The cell growth was inhibited at above 15$\times$$10^{-4} (kcal/cm^2/h)$ of light intensity in an outdoor cultivation. It was also showed that temperature is one of the critical growth parameters in the outdoor cultivation. The hydrocarbon production from D. salina 1650 seems to be partially growth related production process, and these algal hydrocarbons can be used for subsituting petroleum directly or through cracking processes. The value of weight fraction carbon of D. salina 1650 was similar to that of Botryococcus braunii and so was the hydrocarbon productivity.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.278-286
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• 2023

The present work evaluated the production of biohydrogen under mesophilic and thermophilic conditions through dark fermentation of palm oil mill effluent (POME) in batch mode using the design of experiment methodology. Response surface methodology (RSM) was applied to investigate the influence of the two significant parameters, POME concentration as substrate (5, 12.5, and 20 g/l), and volumetric substrate to inoculum ratio (1:1, 1:1.5, and 1:2, v/v.%), with inoculum concentration of 14.3 g VSS/l. All the experiments were analyzed at 37 ℃ and 55 ℃ at an incubation time of 24 h. The highest chemical oxygen demand (COD) removal, hydrogen content (H₂%), and hydrogen yield (HY) at a substrate concentration of 12.5 g COD/l and S:I ratio of 1:1.5 in mesophilic and thermophilic conditions were obtained (27.3, 24.2%), (57.92, 66.24%), and (6.43, 12.27 ml H₂/g COD_rem), respectively. The results show that thermophilic temperature in terms of COD removal was more effective for higher COD concentrations than for lower concentrations. Optimum parameters projected by RSM with S:I ratio of 1:1.6 and POME concentration of 14.3 g COD/l showed higher results in both temperatures. It is recognized how RSM and optimization processes can predict and affect the process performance under different operational conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.872-879
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• 2010

Textured vegetable protein (TVP) was fermented by the solid-state fermentation using Bacillus subtilis HA and biologically active compounds were produced by fermentation for 7 days. The longer fermentation time resulted in the color change of fermented TVP with strong dark red and yellow color. Melanoidin production rapidly increased until fermentation for 48 hr, but did change afterwards. The 70% ethanol extract of TVP fermented for 24 hr showed higher DPPH radical scavenging effect with $IC_{50}$ of 0.99 mg/mL but longer fermentation did not increase its activity. Also, 70% ethanol extract of TVP fermented for 72 hr indicated higher ABTS radical scavenging effect with $IC_{50}$ of 1.68 mg/mL. Consistency index in TVP fermented for 48 hr was the highest values with 7.89 $Pa{\cdot}s^n$. Viscoelastic properties of TVP fermented for 48 hr were maximally enhanced, and viscous value (G") is higher than the elastic value (G'). The $\gamma$-polyglutamic acid (PGA) content was increased by increasing fermentation time with 37.72% of $\gamma$-PGA at 168 hr. However, levan content and molecular weight of PGA were decreased with increasing fermentation time from 7.83% to 3.91% and 1649.3 kDa to 1286.8 kDa, respectively.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.1
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• pp.63-70
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• 1979

In order to improve the quality of greenish tobacco leaves, fermentation experiments by microbial treatment and periodical variations of fermentation temperature were performed. More than twenty strains were isolated from Hyangcho ( Sun cured Korean native leaves ) and Perique tobacco leaves. Among them, five strains which showed good growth in Nicotine Broth medium were selected. Identification experiments of these strains as well as checking the effects of fermentation by these treatment on the quality and aging rate of greenish tobacco leaves were carried out. The results were like following ; 1. Selected strains were identified as pseudomona.f for H-82, for P-4 and Bacillus for H-81. p- 4 and P-7. 2. Among the five strains, strain H- 82 showed the best effect on the forced aging and the quality of greenish tobacco leaves, The rate of oxygen uptaking, pH and nicotine contents were decreased. However, total volatile acids and petroleum ether extracts were increased. 3. After fermentation, taste from greenish tobacco leaf were removed and smoking characteristics were improved. Color was also changed from greenish yellow to dark brown.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.950-957
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• 2009

Mustard Leaf Kimchi (MLK) is a traditional fermented Korean vegetable food. This study was conducted to investigate the effects of part vacuum treatment on MLK packed in a glass bottle during fermentation. There have been a few previous studies that examined the chemical and microbial changes during MLK fermentation. However, the major object of this study was to investigate the antioxidative activities of vacuum treated MLK. In this study, the antioxidative activity of vacuum treated mustard leaf Kimchi (VM) and control mustard leaf Kimchi (CM) were examined. VM and CM were fermented at $5^{\circ}C$ for 8 weeks. A model system was designed to evaluate the antioxidative activity of crude chlorophylls and carotenoids (CCC) extracts from Mustard leaf Kimchi. The oxidative reaction of the linoleic acid mixture system at $30^{\circ}C$ in the dark was quantified determining the peroxide value and conjugated dienoic acid content. The effect of the CCC extracts on lipid peroxidation in a rat liver homogenate was examined. Formation of lipid peroxides was estimated by the TBA value, and the CCC extracts were found to inhibit the TBA value. Chlorophyll a and b, and carotenoids, Which are the major components in the CCC extracts of Kimchi were isolated on a DEAE-sepharose CL-6B and Sepharose CL-6B column and TLC. The effects of chlorophyll a and b, caroteins on linoleic acid autoxidation were measured by determining the peroxide value. In addition, their effects on free radical scavenging were investigated by DPPH. In this assay, chlorophyll a showed the greatest antioxidative activity followed by chlorophyll b, and carotenoids. MLK contains a sufficient content of chlorophyll a and b, and carotenoid which have strong antioxidative activities.