• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.150-155
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• 1997

The twenty strains of Lactobacillus genus were tested for the optimal sponge fermentation of soda cracker. The six strains such as L. brevis, L. delbrueckii, L. fermentum, L. leichmanii, L. plantarum and L. sanfrancisco were selected because these strains did not smell off-flavor and showed the high value of TTA (total titrable acidity) after the fermentation. The selected strains consisted of the five strains of L. brevis, L. delbrueckii, L. fermentum, L. leichmanii and L. plantarum that mainly inhabited soda clacker and L. sanfrancisco that existed in San Francisco bread. The lactic acid bacteria were inoculated to the medium containing 10% wheat flour and then pH, TTA, acetic acid and lactic acid were measured during the sponge fermentation. The four strains of L. brevis, L. delbrueckii, L. fermentum and L. plantarum were used for the mixed lactic acid bacteria of sponge fermentation because the TTAs of L. brevis, L. fermentum and L. plantarum were higher than those of other lactic acid bacteria and L. delbrueckii rapidly produced organic acids and a large amount of acetic acid. Among the combination of L. brevis, L. fermentum, L. delbrueckii and L. plantarum, the mixed lactic acid bacteria of L. brevis, L. fermentum and L. plantarum showed the highest TTA, the lowest pH and the largest amount of acetic acid. Therefore, the mixed lactic acid bacteria of L. brevis, L. fermentum and L. plantarum were used for optimal sponge fermentation of soda cracker.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.23-32
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• 1989

This experiment was performed to investigate the growth and acid production of lactic acid bacteria in soy yoghurts prepared from soybeans produced using various nitrogen sources and the ability of the bacteria to utilize the available carbohydrates in the medium. Various soybeans did not show significant difference in the growth and acid production of lactic acid bacteria, soybean D with newly developed complex fertilizer being the best. The acid production in soy milk by L. acidophilus was better than those in defatted soy milk and in isolated soy protein, that in isolated soy milk being significantly poor. Of lactic acid bacteria tested, L bulgaricus and L. acidophilus exhibited more population and acid production in soy yoghurts. The population and acid production of lactic acid bacteria was increased by the addition of various carbohydrates, and significantly by glucose and yeast extract.

• Journal of Korea Foresty Energy
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• v.24 no.2
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• pp.31-36
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• 2005

Cauliflower mushroom (Sparassis crispa) is an edible mushroom that shows remarkably high contents of $1,3-{\beta}-D-glucan$ compared to other edible mushrooms. The mushroom is known to give high antitumor and immunologic activities, thus the mushroom is recently cultivated in Japan and Korea. However, cultivation methods are being kept in secret or under patents by some companies with complicated procedures. This study was conducted to solve the problem by providing a simple method for the cultivation of cauliflower mushroom. We could produce the mushroom using sawdust-based media of Larix leptolepis, Pinus densiflora and P. koraiensis with addition of barley flours and sugar. The ratio of the sawdust : barley flours : sugar used for this study was 80:20:3 in dry-weight base, and the water content was adjusted as 65%. The productivity was somewhat different among the species of sawdust media and the strains of Sparassis crispa for the cultivation, and the mushroom production reached up to 177g from 650g base(productivity : 27%). Thus, this medium is strongly recommended as a practical cultivation method for cauliflower mushroom. By the way, further study for the determination of adequate concentration of barley flour and the selection of proper strain for each sawdust species is needed.

• KSBB Journal
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• v.27 no.6
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• pp.352-360
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• 2012

Bacillus clausii I-52 which produced SDS- and $H_2O_2$-tolerant extracellular alkaline protease (BCAP) was isolated from heavily polluted tidal mud flat of West Sea in Incheon, Korea and stable strain (transformant C5) of B. clausii I-52 harboring another copy of BCAP gene in the chromosome was developed using the chromosome integration vector, pHPS9-fuBCAP. When investigated the production of BCAP using B. clausii transformant C5 through pilot-scale submerged fermentation (500 L) at $37^{\circ}C$ for 30 h with an aeration rate of 1 vvm and agitation rate of 250 rpm, protease yield of approximately 105,700 U/mL was achieved using an optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_4{\cdot}7H_2O$ 0.01%, $FeSO_4{\cdot}7H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). The enzyme stability of BCAP was increased by addition of polyols (10%, v/v) and also, the stabilities of BCAP towards not only the thermal-induced inactivation at $50^{\circ}C$ but also the SDS and $H_2O_2$-induced inactivation at $50^{\circ}C$ were enhanced. Among the polyols examined, the best result was obtained with propylene glycol (10%, v/v). The BCAP supplemented with propylene glycol exhibited extreme stability against not only the detergent components such as ${\alpha}$-orephin sulfonate (AOS) and zeolite but also the commercial detergent preparations. The granulized enzyme of BCAP was prepared with approximately 1,310,000 U/g of granule. Wash performance analysis using EMPA test fabrics revealed that BCAP granule exhibited high efficiency for removal of protein stains in the presence of anionic surfactants as well as bleaching agents. When compared to Savinase 6T$^{(R)}$ and Everlase 6T$^{(R)}$ manufactured by Novozymes, BCAP under this study probably showed similar or higher efficiency for the removal of protein stains. These results suggest that the alkaline protease produced from B. clausii transformant C5 showing high stability against detergents and high wash performance has significant potential and a promising candidate for use as a detergent additive.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.358-364
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• 2006

This study was conducted to develop optimal solid culture medium for Tricholoma matsutake. As the solid matrix, granitic soil, perlite, vermiculate, pine sawdust and peat moss were compared regarding their effected on mycelial growth. Ergosterol content which is a fungal wall component was used as the growth index of the mycelia. Among the various solid matrixes, the granitic soil, perlite and mixture of the two supported the growth most. Barely flour appeared to be very effective on the stimulating of the mycelial growth when added to the solid matrix. An mixture of the matrix contained an even (1:1:1:1, v/v/v/v) mixture of granitic soil, perlite, vermiculate and pine sawdust. T. matsutake started growth 2 weeks after inoculation and reached stationary growth phase after 8th weeks in the solid matrix mixture. The mycelial density in the solid matrix was 7 times higher than that in fairy-ring soil. In addition, 30~70% water content and 10% humus soil in the solid matrix also supported good growth suggesting that T. matsutake needs humus soil for a nutrient sources. The solid matrix developed in the present study could be used to study physiological characteristics of T. matsutake as well.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.547-555
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• 2014

The purpose of this study is to understand consumer awareness and preference regarding rice cakes by surveying the awareness, preference, and consumption behavior of college students regarding rice cakes, and to survey their perception and usage of rice cakes, thereby using the results as basic data to establish measures to develop Korea's rice cakes. To sum up the study's results, the survey included both male (54.5%) and female (45.5%) subjects. Those aged "20 to 23" accounted for the largest share (67.9%) of total respondents, and those majoring in "humanities and social studies" comprised the largest portion (47.8%). A majority of the respondents resided in "small and medium-sized cities", and most either lived at home or lived away from their families. A majority of the subjects received monthly allowances ranging from 200,000 to 300,000 won. In order of awareness, the most well-known type of rice cake was "injeolmi (rice cake made from glutinous rice and coated with bean flour)", followed by "songpyeon (half-moon-shaped rice cake)", "garaeddeok (bar rice cake)", and "baekseolgi (steamed white rice cake)". The women were better aware of "injeolmi", "baekseolgi", and "garaeddeok" than the men, and "soemeoriddeok" was not commonly known among either gender. In terms of preferences for rice cakes, overall, the subjects liked "injeolmi" and "songpyeon" the most. However, certain differences were found in preferences for rice cakes between the men and women. The women exhibited higher levels of preference for "injeolmi" and "songpyeon" than the men. On the other hand, the men revealed higher levels of preference for "baekseolgi", "jeolpyeon", and "garaeddeok" than the women. The most common answer to important factors for popularizing rice cakes was "a diverse assortment of rice cakes", followed by "the development of creative technologies" and "the taste of rice cakes reflecting consumer needs", in order of importance. Among the important factors to popularize rice cakes, "the development of unique packaging containers for rice cakes" (p<0.05) and "the development of proper packaging materials" (p<0.05) showed statistically significant differences. In the survey of consumption of rice cakes, the most frequent answer to the question "why do you like rice cakes? was "their tastes are good" with 146 respondents, followed by "I have been eating them for long" with 115 respondents. To the question "when do you use rice cakes", the most frequent answer was "I use them in daily life" with 133 respondents, followed by "I use them at special events" with 115 respondents. The women were found to use rice cakes frequently in daily life, whereas the men used them frequently at special events. When asked whether they had the intention to use rice cakes as a meal substitute, 100 men answered that they had no intention, whereas 96 women answered that they had the intention. When asked about the type of rice cake considered suitable for a meal substitute, the most popular answer was "injeolmi" with 108 respondents, followed by "baekseolgi" with 106 respondents.

• Food Science and Preservation
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• v.21 no.1
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• pp.40-45
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• 2014

The effects of adding varying amounts (0%, 1.5%, 3%, 6%, and 12%) of the medium roasted coffee powder on the quality characteristics of rice cookies, which were prepared without wheat flour, were studied. The ingredients were mixed, cut, baked at $170{\sim}180^{\circ}C$ for 10 min, cooled, and packaged in plastic bags. Lightness ($L^*$), yellowness ($b^*$), chroma ($C^*$), and hue angle ($h^{\circ}$) of cookies decreased as the addition amount of the coffee powder increased. Redness ($a^*$) increased with the amount of the coffee powder. Firmness and phenolic compounds tended to increase with the increase in coffee content, however, the firmness levels of the cookies containing 1.5~3% coffee powder were insignificantly different. Antioxidant activity of cookies increased with the increase in the amount of coffee powder. Antioxidant activity of the cookies added with 3% coffee powder was significantly higher than that of the cookies added with 1.5% coffee powder. As a results of the sensory evaluation, the intensity of darkness, smell, bitterness, hardness of the cookies tended to increase with the increase in the amount of coffee powder. The overall acceptability of the cookies was significantly higher for the cookies containing 1.5~3% coffee powder than for the other samples. These results suggested that coffee powder (approximately 3%) can be utilized as an additive for preparing rice cookies which have simultaneously high antioxidant activity and acceptability.

• Food Science and Preservation
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• v.23 no.6
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• pp.883-889
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• 2016

A new lactic acid bacteria with gluten-degrading activity which was isolated from salted sea foods (traditional Korea fermented food), identified as Weissella confusa (99%) by use of API kit and 16S rRNA sequencing, and designated as W. confusa. When the W. confusa cultured for 48 hours at $30^{\circ}C$ in a MRS medium containing 1% gluten, 45% of gluten was founded to be degraded. W. confusa showed 85% of survival rate at pH 3, and 94% tolerance at 0.1% oxgall, which indicates that W. confusa would survive in stomach of human. Experiments on the thermostability was confirmed that it has a stability of 70% in $50^{\circ}C$. W. confusa inhibited the growth of some pathogen, except for S. aureus. Results in this study suggest that using W. confusa for fermentation of grain flour containing gluten would be desirable to prepare the gluten-free foods needed for those who suffer from celia disease and gluten allergy.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.163-176
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• 2012

TTo increase productivity of a strong extracellular alkaline protease (BCAP), stable strains of Bacillus clausii I-52 carrying another copy of BCAP gene in the chromosome were developed. Integrative vector, pHPS9-fuBCAP carrying BCAP promoter, ribosome binding site, signal sequence and active protease gene was constructed and transferred into B. clausii I-52, and integration of the constructed plasmid into chromosome was identified by PCR. An investigation was carried out on BCAP production by B. clausii I-52 and transformant C5 showing the highest relative activity of alkaline protease using submerged fermentation. Maximum enzyme activity was produced when cells were grown under the submerged fermentation conditions at $37^{\circ}C$ for 48 h with an aeration rate of 1 vvm and agitation rate of 650 rpm in a optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_47H_2O$ 0.01%, $FeSO_47H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). A protease yield of approximately 134,670U/ml was achieved using an optimized media, which show an increase of approximately 1.6-fold compared to that of non-transformant (83,960 U/ml). When the stability of transformant C5 was examined, the integrated plasmid pHPS9-fuBCAP was detected in the transformant after cultivation for 8 days, suggesting that it maintained stably in the chromosomal DNA of transformant C5.

• Journal of Mushroom
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• v.20 no.2
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• pp.55-60
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• 2022

This study was conducted to establish an appropriate period of use of sawdust spawn at low temperatures and a nutrient supplement medium for cultivation of Lentinula edodes 'Hwadam'. Of the nutrient supplements, the total yield of rice bran (5%) + corn flour (5%) treatments were 673.3 g, which was higher than rice bran (551.6 g) and wheat bran (546.7 g) treatments, respectively. As shown by the growth of Lentinula edodes 'hwadam' during to the sawdust spawn storage period (at 4℃), the period of spawn running, browning, fruiting body formation, and development was 27 d, 81 d, 5 d, and 11-13 d, respectively, regardless of the length of the storage period at 4 ℃. After 3 months of storage of sawdust spawn, the number of fruiting bodies and yield decreased as the storage period increased. Therefore, the period of use of sawdust spawn (at 4 ℃) for the stable production of fruiting bodies of Lentinula edodes 'Hwadam' was a maximum of 3 months.