• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.584-589
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• 2005

Structured triacylglycerol (SL-TAG) was synthesized by enzymatic interesterification with algae oil and soybean oil in solvent-free system. Structured di- and monoacylglycerol (SL-DAG/MAG) were produced by glycerolysis with SL-TAG and glycerol catalyzed by lipase. Reactions were performed by sn-1.3 specific Lipozyme RM IM lipase from Rhizomucor miehei (interesterification, 11%; glycerolysis 5% by weight of total substrates) in solvent-free system using stirred-batch type reactor. SL-DAG/MAG contained TAG (42,3 area%), 1,3-DAG (19.2 area%), 1,2-DAG (22.2 area%), MAG (16.0 area%), and free fatty acid (0.2 area%). Iodine and saponification values of SL-DAG/MAG were 208.8 and 179.6, respectively. SL-DAG/MAG appeared yellowish in color.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.149-153
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• 1992

Antioxidative effects of crude ethanol extract of the Rhus javanica L. and its fractionates with various synergists on the oxidation of palm oil, lard and soybean oil were compared with induction period(IP) using a Rancimat test. Addition of 200 ppm of the crude extract with phosphoric acid to palm oil extended IP 2.89 times as much as that of control and ethyl acetate fractionate extended IP 4.18 times at the same condition. To lard, 600 ppm of chloroform fraction with 200 ppm of ${\delta}-Tocopherol$ extended IP 13.42 times as much as that of control. 200 ppm of each fraction with various synergists were added to palm oil and lard, and oxidative stability of the oils were monitored by measuring POV, AV, and TBA value. The POV of palm oil containing 200 ppm of ethyl acetate and chloroform fraction with 200 ppm of phosphoric acid after 27 days storage at $60^{\circ}C$ were 8.9 meq/kg and 9.4 meq/kg respectively while the POV of control was 98.3 meq/kg at the same condition. AV and TBA value were also lower than that of control. The POV value of lard containing same amount of ethyl acetate and chloroform fraction with ${\delta}-Tocopherol$ after 12 day storage at $60^{\circ}C$ were 20.0meq/kg and 10.7 meq/kg respectively while the POV of control was 161.1 meq/kg at the same condition. AV and TBA value were also lower than that of control.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.154-160
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• 2000

Protease production and its characteristics were investigated with Bacillus subtilis PCA20-3 which was isolated from Korean traditional meju. The optimum culture conditions of Bacillus subtilis PCA20-3 for the production of the protease were as follow: 0.2% soytone, 2% starch, 0.1% $(NH_4)_2SO_4,\;0.2%\;CaCl_2,\;0.01%\;yeast\;extract,\;0.1%\; K_2HPO_4,\;0.1%\;KH_2PO_4,\;pH\;7.0,\;30^{\circ}C$ and 20 hrs. The optimum pH and temperature for enzyme activity of protease producing Bacillus subtilis PCA20-3 were pH 8.0-10.0 and $55^{\circ}C$, respectively. The enzyme was relatively stable at pH $6.0{\sim}11.0$ and at temperature below $50^{\circ}C$. The activity of the enzyme was inhibited by $Fe^(2＋)\;and\;Cu^(2＋)$. 2 mM phenymethanesulfonyl fluoride inhibited 89.2% of enzyme activity. This indicates that the enzyme is serine protease. The $K_m$ value was $5\;{\times}\;10^{-4}\;M,\;V_{max}\;value\;was\;100\;{\mu}g/min$. This enzyme hydrolyzed casein more rapidly than bovine serum albumin.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.161-167
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• 2000

The protease produced by a newly isolated Aspergillus wentti from Korean traditional Meju was purified and characterized. The optimal medium composition and culture conditions for maximum protease production were ; bran :1% glucose solution =1 : 1, pH 9.0, $30^{\circ}C$, and 4 days of fermentation. Protease was purified by QAE-Sephadex, SP-Sephadex ion exchange chromatography and Sephadex G-100 chromatography. The specific activity and the purification fold of the purified enzyme were 213 unit/mg protein and 27.3, respectively. The molecular weight of purified protease was found to be 32 kDa by SDS-PAGE. Km and Vmax value's for hammastein milk casein were $3.049{\times}10^{-4}\;M\;and\;151.1\;{\mu}g/min$, respectively. Kinetic parameters showed that the enzyme has higher affinity to casein than isolated soybean protein, hemoglobin and bovine serum albumin. Optimal pH and temperature for reaction of the purified enzyme were 9.0 and $50^{\circ}C$, respectively. The enzyme was stable at pH 4.0-11.0, below $40^{\circ}C$, and the activity was not stimulated by metal ions. 1mM phenylmethylsulfonyl fluoride inhibited the enzyme activity by 98.5%. It means that the enzyme is one of serine protease.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.232-241
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• 1979

For the effective utilization of the fish resource in coastal regions, an investigation on optimum processing conditions and meat quality textured fish protein concentrate (FPC) was carried out with the fish meat of filefish and sardine. Optimum pH and sodium chloride content of fish meat were 7.5 and 1.0 %, respectively. The most effective soaking conditions were as follows ; soaking time, 30 min ; temperature of ethanol, 5 to $20^{\circ}C$ ; amount of added ethanol, 3 times the weight of the fishmeat paste ; repeated number of soaking in ethanol for filefish and sardine, 2 and 4, respectively. The ethanol remaining is meaty textured FPC could be removed effectively by forced-air drying. Yields of the product to the minced meat weight and the contents of protein lipid in meaty textured from filefish were 21.1, 77.6 and 0.2 % and those from sardine were 24.3, 75.8 and 3.6 %, respectively. Contents of essential amino acids in meaty textured FPC of filefish and sardine were not inferior to those of beef, textured soybean protein and FAO pattern. Beef meat could be substituted with the meaty textured FPC up to 50 % in the processing of typical meat balls and hamburger without any significant loss in its taste, odor and texture.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.63-72
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• 1978

Effect of shapes (noodle, grain and brick types) and strains (Aspergillus oryzae and Aspergillus sojae) of Meju (microorganism inoculated soybean substrate for fermentation) on the quality of soy sauce was investigated. Generally, the highest protease activity was found in the noodle type-Meju inoculated Asp. sojae during Meju preparation and soy sauce brewing, however, the lowest value was noted in brick type. Meju inoculated Asp. oryzae. Similar tendency was found on the contents of total solid, total nitrogen, amino-nitrogen, nitrogen digestion yield and amino-nitrogen ratio during soy sauce brewing. No effect was shown on the reducing sugar content, alcohol formation, pH, buffer action and salt content according to different Meju types during soy sauce brewing. Organoleptic tests on the color, taste and flavor of soy sauce after 3 months brewing with various Meju scored in the order of noodle type-Asp. sojae soy sauce (best quality), noodle type-Asp, orzae soy sauce, brick type-Asp. sojae soy sauce and brick type-Asp. oryzae-soy sauce (worst quality).

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.319-327
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• 1981

In order to reproduce and improve the Korean traditional Kochujang(fermented hot pepper-soybean paste), traditional and improved Kochujang Koji were prepared according to the standard method investigated in Chunrabookdo area and combined the raw materials of Kochujang by the traditional habit. Amino nitrogen contents were higher in improved Kochujang than in traditional one, those were in the range from 83 to 106 mg% immediately after brewing and 191 to 313 mg% at the end stage of brewing. Water soluble and ammonia nitrogen contents were most high in the improved Kochujang which was mixed with sodium chloride and brewed soysauce as seasoning. The content of reducing sugar of traditional Kochujang was higher than that of improved one during the brewing. Ethyl alcohol contents of all Kochujang samples were 0.04% at the early stage of brewing and that reached above 2.5% after $40{\sim}50$ days brewing.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.399-404
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• 2009

The goal of this study was to improve the quality of cheonggukjang by the optimization of the inoculation methods of the Bacillus subtilis (B. subtilis) and Lactobacillus plantarum (L. plantarum) strains. In order to optimize the mixed cultivation of B. subtilis and L. plantarum, the B. subtilis strain was inoculated into steamed soybeans after cultivation of L. plantarum. Inoculation size of B. subtilis was changed to the simultaneous inoculation method in order to stimulate the growth of the L. plantarum in cheonggukjang. The viable cell count of L. plantarum increased from $2{\times}10^7$ CFU/g to $2-6{\times}10^8$ CFU/g and B. subtilis grew to $9{\times}10^8$ CFU/g. These results showed that 2 strains were successfully able to grow in the steamed soybean for good quality of cheonggukjang by optimization of the inoculation methods. The sensory evaluation indicated that a favorable aroma and overall acceptance of cheonggukjang by the optimized mixed cultivation of B. subtilis and L. plantarum, which was relatively higher than those of cheonggukjang by single strain inoculation of B. subtilis.

• Journal of Life Science
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• v.21 no.9
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• pp.1315-1322
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• 2011

This study was conducted to investigate the effects of several herbal extracts (obtusifolia, cinnamon, chinese pepper, licorice root) on the characteristics of rumen fermentation in vitro. Soybean meal was used as a substrate for fermentation in vitro. Herbal extracts were supplemented to media by 10% of the substrate. The substrates supplemented to Dehority artificial media with herbal extracts were fermented in 30ml serum bottles for 0, 3, 6, 9, 12 and 24 hr at $39^{\circ}C$. Cumulative gas production was significantly (p<0.05) greater in the herbal extract supplements than in the control, in the order of licorice root, chinese pepper, cinnamon and obtusifolia. Methane proportions of the herbal extracts were significantly (p<0.05) higher than that of the control. Licorice root extract supplementation resulted in the lowest methane proportion at 3 hr fermentation. Proportion of hydrogen was significantly (p<0.05) higher in the herbal extract supplements than in the control at 12 hr fermentation. Compared to the control, ammonia concentration in the licorice root was significantly higher at 3 hr fermentation, but lower at 12 hr fermentation (p<0.05). Based on these results, supplementation of the herbal extracts used in this experiment resulted in increased cumulative gas production and stimulating methane production in vitro rumen fermentation.

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.153-157
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• 1984

In order to investigate an etiological characteristics of the pepper anthracnose fungus infected with Collectotrichum dematium, this experiment was undertaken. Isolation percent of the fungus was 55.3% from the seed sample of Jewon and 0.3% from that of Eumsung Kun, according to seed health blotter method. Although the acervulus was similar to the known two Colletotricum species, C. acutatum and C. gloeosporioides, setae was not only straightly extended above the acervulus, but also shaped as falcate conidia ranging $12{\sim}31.2{\times}2.4{\sim}4.8{\mu}m$. Acervului of the fungus were evenly scattered on the surface of pepper seed coat, and caused seedling blight after seed germination. Pre-and post-emergence seedling blight as well as foliar lesion and fruit rot was confirmed by inoculating conidial suspension. No typical anthracnose sysmptom was obtained from soybean seedlings, welsch onion and spinach seedlings upon inoculation. Therefore, this fungus is said to the undescribed form species of the fungus of pepper in Korea (Colletotricum dematium f. sp. capsicum).