• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.858-860
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• 2011

Production of biosurfactant can be substantially increased by the addition of precursors like vegetable oils, petroleum products, and other water-insoluble substances. Pseudomonas Ptm+ strain produces biosurfactant in the presence of hexachlorocyclohexane (HCH), which specifically emulsifies HCH, a recalcitrant organochlorine pesticide. Addition of previously produced crude biosurfactant by the same organism as a precursor instead of HCH increased production of biosurfactants with a decrease in the total fermentation time from 32 to 24 h. The main objective of this paper was to find alternatives for HCH as an inducer.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.74.3-74
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• 2001

This paper proposes a nonlinear adaptive controller based on back-stepping method for tracking reference substrate concentration by manipulating dilution rate in a continuous baker´s yeast cultivating process in stirred tank bioreactor. Control law is obtained from Lyapunov control function to ensure asymptotical stability of the system. The Haldane model for the specific growth rate depending on only substrate concentration is used in this paper. Due to the uncertainty of specific growth rate, it has been modified as a function including the unknown parameter with known bounded values. The substrate concentration in the bioreactor and feed line are measured. The deviation from the reference is observed when the external disturbance such as the change of the feed is introduced to the system ...

• Food Science and Biotechnology
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• v.18 no.1
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• pp.150-156
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• 2009

In this study, Staphylococcus carnosus isolated from traditional sucuk (Turkish dry-fermented sausage) was used in combination with Lactobacillus plantarum as a lactic culture in sucuk production. Sucuk produced with only L. plantarum was evaluated as a control group. Microbiological, physicochemical, and volatile profile characteristics of sucuk samples were investigated during ripening. In both sausages with S. carnosus and control group, pH value decreased to below 5.0 at the $3^{rd}$ day. In all samples, Aw value decreased as the ripening time progressed. Sausages with S. carnosus showed the higher nonprotein nitrogen (NPN) value than control group. However, the highest mean value for thiobarbituric acid reactive substances (TBARS) was observed in control group. Enterobacteriaceae dropped to undetectable levels at the $3^{rd}$ day in both groups. S. carnosus increased approximately 1 log unit within the first 3 days of the fermentation. In the presence of S. carnosus, significant changes were observed in only a few volatile compounds.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1048-1064
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• 2005

Detection of specific compounds influencing food flavor quality is not easy. Electronic nose, comprised of electronic chemical sensors with partial specificity and appropriate pattern recognition system, is capable of recognizing simple and complex volatiles. It provides fast analysis with simple and straightforward results and is best suited for quality control and process monitoring of flavor in food industry. This review examines application of electronic nose in food analysis with brief explanation of its principle. Characteristics of different sensors and sensor drift. and solutions to related problems are reviewed. Applications of electronic nose in food industry include monitoring of fermentation process and lipid oxidation, prediction of shelf life, identification of irradiated volatile compounds, discrimination of food material origin, and quality control of food and processing by principal component analysis and neural network analysis. Electronic nose could be useful for quality control in food industry when correlating analytical instrumental data with sensory evaluation results.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.4
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• pp.309-317
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• 2016

The study was conducted to evaluate the effects of microbial culture supplements on ruminal fermentation and fermentative quality of Italian ryegrass silage (IRGS) both in vitro and in situ. Three species of microbes (Lactobacillus casei (LC), Bacillus subtilis (BS), and Saccharomyces cerevisiae (SC)) were used in this study. They were applied to IRGS at 30 days after silage manufacture. Various items were measured using in vitro and in situ incubation technique after each microbial supplement was inoculated into IRGS at $0.5{\times}10^4CFU/g$. In the first experiment, in vitro ruminal fermentation characteristics of IRGS were evaluated at 0, 12, 24, 48, and 72 hours after microbes were inoculated into IRGS. In the second experiment, in situ fermentation characteristics were investigated at 0, 1, 3, and 5 days after the inoculation of each microbial supplement. In vitro ruminal $NH_3-N$ content was significantly (p<0.05) increased in LC-, BS-, and SC-IRGS at 12 hrs post incubation compared to that in control IRGS. In vitro ruminal total VFA concentration and dry matter digestibility (DMD) of IRGS were not significantly difference among LC-, BS-, and SC-IRGS, although they were numerically increased in LC-IRGS than those of the other IRGS. In addition, this study evaluated the fermentation characteristics and in situ DMD of IRGS with the lapse of incubation time up to 5 days. Throughout the incubation times from 1 day to 5 days, the pH value was significantly (p<0.05) lower in BS-, LC-, and SC-IRGS than that in control IRGS. Lactate was significantly (p<0.05) higher, and significantly (p<0.05) butyrate was lower in LC-IRGS than that in other treatments at 0 day. It was higher (p<0.05) in control IRGS than that of BS-, LC-, and SC-IRGS at 1-5 days. In situ DMD tended to increase in BS-, LC-, and SC-IRGS compared to that in control IRGS. Especially, DMD was higher in SC-IRGS than that in other treatments at 0 day. It tended to be higher in LC-IRGS at all incubation time. Taken together, these results suggest that it might be useful to select a microorganism by considering the feeding time of IRGS to ruminants because organic acids and DMD of IRGS were affected by the incubation time of each microorganism with IRG silage, especially for L. casei decreased the content of acetate and butyrate in IRGS.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.273-281
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• 2011

Rice bran is byproducts of the hulling of rice, an important food resource in Korea. Various studies have been reported immune-enhancing effects of rice bran cultured with Lentinus edodes. In particular black rice bran contains anthocyanin, and the effects of antioxidant have been reported. The objective of the this study was to investigate the possible immune-enhancing effects of black rice bran substance extracted from a submerged culture of Lentinus edodes with black rice bran (crude fermentation-polysaccharide, CFP) and products(crude fermentation-polysaccharide-S. cerevisiae CFP-S, crude fermentation-polysaccharide-L. gasseri, CFP-L) which are of secondary fermentation of by using Saccharomyces cerevisiae and Lactobacillus gasseri in the Blab/c male mice. We found that supplementation of CFP, CFP-S and CFP-L enhanced macrophage and splenocyte proliferation compared to the control group(NC) in mice. Also, we measured the concentration of cytokines(IFN-${\gamma}$, TNF-${\alpha}$, IL-6) secreted by activated macrophage and splenocyte. The results of the experiment are that supplementation of CFP and CFP-S increased the macrophage and splenocyte proliferation compared to the control group but supplementation of CFP-L decreased the splenoyte proliferation compared to the control group(without mitogen and treated with LPS). When macrophage and splenocyte were stimulated by CFP and CFP-S supplementation, it was increased IFN-${\gamma}$, TNF-${\alpha}$ and IL-6 concentration compared with the control group. These results suggest that the capacity of CFP and CFP-S seem to act as a potent immune modulator causing augmentation of immune cell activity, and enhance the immue function through regulating cytokine production capacity by activated macrophage and splenocyte in mice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1265-1273
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• 2005

The purpose of this study was to prepare accelerated salt-fermented anchovy sauce using a shrimp processing byproducts (head, shell and tail) as a fermenting accelerator, and to investigate its physicochemical and enzymatic properties. Four types of sauces were prepared with 0, 10, 20, and 30$\%$ (w/w) addition of shrimp byproduct and fermented at 24$\pm$2$^{\circ}C$ for 360 days. During fermentation, all four type sauces decreased moisture content (67.5$\%$68.0$\%$ to 64.0$\∼$64.8$\%$) and pH (5.52$\∼$7.10 to 5.03$\∼$6.58), but showed increase in their crude protein (7.0$\∼$8.2 to 10.8$\%$) and volatile basic nitrogen contents (40$\∼$75 to 180$\∼$200 mg/100 g of sauce). The ratio of amino nitrogen to total nitrogen contents of control (0$\%$) and sauce with 10$\%$ shrimp byproducts (10$\%$ sauce) were maximized at 270 days, whereas 20$ \% $ and 30$\%$ added sauces were at 180 days. Endoprotease and exoprotease activities of anchovy sauces added with 20$\%$ and 30$\%$ of shrimp byproducts tend to be higher than those of control (0$\%$) and 10$\%$ addition. Proteolytic activities of sauces at pH 9 were about 2 times higher than those at pH 6. Amidolytic activities for LeuPNA decreased remarkably during fermentation, and control (0$\%$) almost lost their activity at 180 days, while additional sauces were relatively stable. These suggest that alkaline pretense of anchovy and shrimp byproducts as a endoprotease mainly contributed to the fermentation of salt-fermented sauces. The protein molecular weight distribution of sauces indicated 2 groups of peaks (peak 1,>70,000 da and peak 2, 3,000$\∼$29,000 da). As the fermentation proceeded, peak 1 tended to decrease in all of sauces, but peak 2 increased rapidly from 30 to 270 days. Optimum fermentation periods of control and 10$\%$ sauces were 270 days and those of 20$\%$ and 30$\%$ sauce were 180 days. The results suggest that shrimp byproduct can be used as accelerator of salt-fermented sauce.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1243-1249
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• 2011

This study was performed to examine the use of NaOCl as an alternative antimicrobial compound in winemaking because of the potential health problems that may arise as a result of the use of $SO_2$. For this, the blank (non-treated), control ($SO_2$-added), and sample (NaOCl-treated) wines were made, and microbial and chemical changes including sensory characteristics were analyzed during the fermentation periods. Treatment of grapes with NaOCl decreased the initial contaminating microbial population in grape must, resulting in higher growth of yeast and lactic acid bacteria. After 200 days of fermentation, the chemical analysis of sample wine revealed that it had higher ethanol content, redness ($a^*$), and concentrations of fruity ester compounds and lower total acidity than the control. In the sensory analyses, the sample wine obtained a higher overall acceptability score (5.70) than the control (4.26). This result reveals that NaOCl can be used as an alternative to $SO_2$ in winemaking for inhibiting the growth of contaminating microorganisms.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.333-337
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• 2007

This study was conducted to assess effects of soil moisture condition and ventilation on development of fermented fruit of oriental melon. In higher soil moisture condition (-10 kPa), roots absorbed more water and transpiration was decreased under low temperature and high humidity conditions. Development of fermented fruit may be come from absorbed water concentrated placenta with higher soluble solid. Fermented fruit was developed with higher level at Shintozoa and Elite, was developed with lower level at Hongtozoa, and was not developed at self-rooting of oriental melon. Ventilation on fruit did not affect development of fermented fruit at Shintozoa, Elite, Hongtozoa and self-rooting seedling. Ca contents of flesh and placenta of fruit under ventilation treatment were higher than control but contents of Acetaldehyde, Ethanol and Ethylacetate were lower.

• Korean journal of food and cookery science
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• v.31 no.2
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• pp.128-135
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• 2015

Blueberry juice extraction (JE), hot water extract (HE), and 50% ethanol extract (EE) were fermented with Lactobacillus plantarum CGKW3. We investigated the quality characteristics and antioxidative activities of yanggaeng prepared with different amounts of fermented blueberry extract (JE, HE, EE). The viable cells in fermented HE was higher (7.49 log CFU/mL) than JE (7.28 log CFU/mL) and EE (6.99 log CFU/mL), during the fermentation period. The viable cells and acidity in yanggaeng increased significantly with increasing levels of fermented blueberry extract (p<0.05). In terms of color, the lightness and yellowness decreased significantly, but redness increased with increasing levels of fermented blueberry extract. In the texture profile analysis, control showed the highest result in hardness. Cohesiveness did not show significant differences, according to amount of fermented blueberry extract. The springiness decreased with the increasing levels of fermented blueberry extract. Antioxidant activity, which was measured by DPPH and reducing power, was significantly higher than those of control; and it increased proportionally according to the amount of fermented blueberry extract. Anthocyanin contents were increased proportionally with the increasing levels of fermented blueberry extract. Sensory evaluation showed that the color, taste, flavor, texture, and overall acceptability of yanggaeng containing the JE, HE, and EE were higher than those of the control.