• Journal of Dairy Science and Biotechnology
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• v.31 no.2
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• pp.143-152
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• 2013

Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the central nervous system of animals, has several physiological effects including anti-hypertensive, diuretic, tranquilizing, and anti-stress properties, in humans. The purpose of this study was to investigate Lactobacillus plantarum K74, which was isolated from kimchi and selected as a strain with a high ability to produce GABA, to develop a new starter culture for fermented milk production. L. plantarum K74 produced $134.52{\mu}g/mL$ GABA in MRS broth containing 1% MSG, $212.27{\mu}g/mL$ GABA in MRS broth containing 2% MSG, and $234.63{\mu}g/mL$ GABA in MRS broth containing 3% MSG. The optimum growth temperature of L. plantarum K74 was $34^{\circ}C$, reaching a pH of 4.4 after 18 hours of growth. L. plantarum K74 was most sensitive to novobiocin out of 16 different antibiotics tested, and was most resistant to kanamycin and polymyxin B. L. plantarum K74 did not produce ${\beta}$-glucuronidase, a carcinogenic enzyme, and was comparatively tolerant to bile juice and low pH. Furthermore, it displayed resistance to Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus at rates of 54.9%, 46.3%, and 0.7%, respectively.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.19-25
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• 2020

Turmeric pigments have been used as coloring agents and functional ingredients. In this study, the extraction property and chemical stability of the pigments were evaluated in several preservative solutions containing NaCl, sucrose, and acetic acid. After 72 h of infusion, the protein and polyphenol levels and antioxidant activity of the turmeric extracts in the solutions were less pronounced than those in water. Acetic acid (12%) was more efficient at extracting curcuminoids from turmeric than water, NaCl (20%), or sucrose (25%). Curcumin was highly abundant in all solutions. The relative yield of bisdemethoxycurcumin (BMC) was the highest in acetic acid, whereas that of curcumin was highest in NaCl and sucrose solutions. Curcuminoids were relatively stable in sucrose and acetic acid; among them, BMC had the highest stability. The stability of the curcuminoid solution decreased based on the increase in NaCl content, whereas it was significantly enhanced in sucrose and acetic acid. The observations from this study can be applied to the processing and storage of turmeric-derived products in these preservative agents.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.301-307
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• 2012

To develop high value added healthy functional resource from Korean mulberry, the bioactive compounds and antioxidant activities of three different mulberry cultivars were investigated and compared with blueberry and strawberry. Total phenolics, total flavonoids, and trans-resveratrol of 'Daesungppong' were the highest than the 'Suwonppong', whereas those of the strawberries were the lowest. In case of total anthocyanins, 'Daesungppong' was also the highest and followed by blueberry. The antioxidant activities of 'Daesungppong' using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid), and FRAP (Ferric reducing antioxidant power) assays were the highest followed by 'Suwonppong'. Meanwhile, there were no significant differences in the antioxidant activities between 'Cheongilppong' and blueberry, and the activities of strawberry were the lowest. Furthermore, there was a strong correlation (r = 0.764-0.897) between DPPH, ABTS, and FRAP assays with the bioactive compounds such as total phenolics, total flavonoids, and total anthocyanins. Therefore, Korean mulberry, especially 'Daesungppong' demonstrated interesting biological properties that suggest its use as a potential source and high value added of natural antioxidant compounds and antioxidant activity.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.395-405
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• 1994

The various functional groups, such as hydroxyl(-OH), carboxyl(-COOH) and quinonic oxygen(OC<) on the carbon black(abbreviated to CB) surface were activated with n-butyl lithium solution in n-hexane and then acrylate and methacrylate monomers were graft polymerized onto these activated anionic sites and CB-grafted polymers were obtained. To separate homopolymers from reaction mixture, non-solvent precipitation method or centrifugal separating method were applied. Subsequently, conversion, grafting ratio and efficiency were determined at various reaction temperatures and times. In case of acrylates, the grafting ratio showed 20~30% but methacrylates showed 150~200%. Also the anion polymerizations between CB and monomers were nearly reached to equilibrium state within one or two hours under each reaction temperatures but conversion and grafting ratio were increased a little with reaction temperature increase. In colloidal dispersion stability test, before heat-drying, the all CB-grafted polymers showed good dispersed stability in good solvents for acrylic and methacrylic homopolymers. Futhermore, CB-polymethacrylates were found to show excellent collidal properties for good solvents of methacrylic homopolymer even after heat-drying. Identification of the grafted polyacrylates and polymethacrylates onto the CB surface was performed by FT-IR spectroscopy. In addition, electric resistance values of CB-grafted polymers were measured by Four-probe method, and the increase of the grafting ratio showed the increase of the surface resistance.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.432-439
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• 2018

Metal catalysts such as Fe, Co, Mn, and Pd supported on the activated carbon (AC) were prepared to improve functional groups for the chemical adsorption and catalytic ozonation. Following ascending orders of the phenol decomposition rate, dissolved ozone decomposition ratio and TOC (total organic carbon) removal from experimental results of advanced oxidation process (AOP) were observed: Fe-AC < AC < Co-AC < Mn-AC < Pd-AC. BET analysis results showed that the physical properties of the metal impregnated activated carbon had no effect on the catalytic ozonation, and the catalytic effect was dependent on the kind of impregnated metal. The ratio of the formed concentration of OH radical to that of ozone (RCT) was measured by using the decomposition outcome of p-chlorobenzoic acid, a probe compound that reacts rapidly with OH radical but slowly with ozone. The measured values of RCT were $5.48{\times}10^{-9}$ and $1.47{\times}10^{-8}$ for the ozone alone and activated carbon processes, respectively, and $2.13{\times}10^{-9}$, $1.51{\times}10^{-8}$, $4.77{\times}10^{-8}$, and $5.58{\times}10^{-8}$ for Fe-AC, Co-AC, Mn-AC, and Pd-AC processes, respectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.25 no.3
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• pp.69-77
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• 2019

Agar-based nanocomposite films were prepared by incorporation of zinc oxide nanoparticles (ZnONP) and grapefruit seed extract (GSE). The composite films were characterized using FT-IR, UV-visible spectroscopy and thermalgravimetric analysis (TGA). The composite films showed light absorption peaks at 220 and 380 nm, characteristic for GSE and ZnONP, respectively. The UV-light transmittance of the agar film was markedly reduced from 54.4 ± 1.3% to 5.8 ± 2.5% with little sacrifice of transparency when 3 wt% ZnONP and 5 wt% GSE were added. The mechanical and water vapor barrier properties increased slightly though they were not significant statistically by the addition of ZnONP and GSE. The nanocomposite films showed stronger antibacterial activity against L. monocytogenes than E. coli O157: H7 and the antibacterial activity was affected by bacterial types as well as concentrations of ZnONP and GSE. The nano-composite film incorporated with 3 wt% of ZnONP and 5 wt% of GSE exhibited strong antibacterial activity against Listeria monocytogenes and E. coli O157: H7. The results indicate that 3 wt% of ZnONP and 5 wt% of GSE are the optimal concentrations for producing functional agar/ZnONP/GSE composite films.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.9-16
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• 1987

This study was designed to determine the amino acid composition and to investigate microstructure by scanning electron micrographs of silkworm larvae protein and modified silkworm larvae protein concentrate. The results were as follows: 1, The protein contents of soybean and silkworm larvae protein concentrate were 70.3% and 84.1%, respectively. 2. In general, the essential amino acid content of silkworm larvae protein concentrate were higher than soybean protein concentrate as well as FAO provisional scoring pattern. Silkworm larvae protein concentrate was especially high in lysine and methionine indicating that it could be a good supplemental source for cereals and beans. Succinylation and acetylation resulted in no difference in most amino acid content. 3. The scanning electron microscopic observations revealed that silkworm larvae protein concentrate had smooth surface topography while defatted silkworm larvae flour showed different shapes and sizes with relatively rough surfaces. Acylated silkworm larvae protein concentrate exhibited less cellularity and denser than protein concentrate. However, succinylated silkworm larvae protein concentrate showed especially good texture indicating that it could increase the functional properties of silkworm larvae protein concentrate.

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.851-858
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• 2014

Goami2, Goami3 and Goami4 were identified as fiber-rich rice cultivars which were developed by mutation breeding with Ilpum. The purpose of this study was to develop a method for producing Makgeolli with the fiber-rich rice cultivars, Goami2, Goami3, Goami4, and to investigate the characteristics of Makgeolli during the fermentation process. Makgeolli was produced herein by fermentation steamed rice (SR), raw rice flour (RF), and steamed rice flour (SF) from Goami2, Goami3, Goami4, Ilpum and Sealgaeng rice cultivars. The physicochemical characteristics including alcohol and sugar content, pH, total acidity, TDF (total dietary fiber), and color of the Makgeolli samples were analyzed. Makgeolli produced with Ilpum and Sealgaeng showed satisfactory fermention characteristics in alcohol and sugar content when SR, RF and SF were used. In the case of Goami2, Goami3, and Goami4, the use of SF resulted in 17.2~20.1% alcohol content, whereas only 10% alcohol was produced by SR. The sugar contents in the SF-makgeolli samples were also higher ($9{\sim}10^{\circ}Brix$) than in the SR-makgeolli ($5.35{\sim}5.44^{\circ}Brix$) for Goami2 and Goami4 cultivars. The dietary fiber contents of the Makgeolli samples produced using SF from the fiber-rich rice cultivars were higher (1.35~1.52 g/100 mL) than those produced with Ilpum and Sealgaeng (0.74~0.87 g/100 mL). From these results, it may be suggested that SF would be an appropriate material to brew Makgeolli using fiber-rich rice cultivars to obtain better physicochemical and functional qualities.

• Food Science of Animal Resources
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• v.30 no.4
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• pp.609-616
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• 2010

This study was conducted to determine the effects of dietary low grade soybean, fermented with Aspergillus oryzae (FSB 1) or Bacillus subtilis var. natto (FSB 2), on egg production and quality, fat and cholesterol content, and the fatty acid (FA) profile of eggs by lipid layer. A total of 18 Hi-Line strain layers, 22 wk of age, were randomly assigned to three dietary treatments: no fermented soybean (control), control with 15% FSB 1 (C + FSB 1), and control with 15% FSB 2 (C + FSB 2). The rate of egg production and egg weight were evaluated between two periods: one was from the 1st to 4th wk and the other was from the 5th to 8th wk. At the 8th wk, a total of 30 eggs were randomly selected from each treatment group and analyzed for physical quality, fat content, fatty acid composition and cholesterol content. The results showed that egg production was increased in hens fed with diets containing fermented soybeans from the 5th to 8th wk period (p<0.01). A similar tendency was observed through eight weeks' cumulative egg production (p<0.05). There were no significant differences in egg production between the C + FSB 1 and C + FSB 2 treatment groups (p>0.05). Egg weight and other physical properties did not vary between treatment groups (p>0.05). Egg yolks among different treatment groups were similar in fat content, but egg yolks in the C + FSB 1 and C + FSB 2 groups had lower oleic acid (p<0.05), higher linoleic, ${\alpha}$-linolenic, and arachidonic acids (p<0.01), and lower cholesterol content (p<0.05) than those in the control group. In conclusion, supplementation of fermented low grade soybeans might be useful as a functional feedstuff to improve egg production and quality for a healthy human diet.

• Culinary science and hospitality research
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• v.16 no.3
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• pp.286-297
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• 2010

This study examines physiochemical characteristics of functional bread with black garlic flour added such as its content, texture, sensory test and quality properties. The loaf volume and weight of black garlic flour-added pan bread showed that for the control, the loaf volume was the greatest, and the more the black garlic flour content increased, the smaller the loaf volume became. The change of crust chromaticity showed that the L value decreased significantly, and crust chromaticity thickened, and as the black garlic flour content increased, a value and b value decreased. The characteristics of texture showed that the hardness and chewiness decreased as the black garlic flour content increased, and gumminess increased significantly while there was no significant difference in cohesiveness. The flavor, taste and texture of pan bread with black garlic flour content didn't showed a significant difference with the control. Consequently, the black garlic flour-added wheat flour was no significant difference with the control up to 3% black garlic flour-added wheat flour, which can be used as a product.