• KSBB Journal
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• v.30 no.5
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• pp.253-256
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• 2015

The antibacterial activity from Tricholoma matsutake extracts were confirmed by minimum inhibitory concentration (MIC) test against various bacteria. Tricholoma matsutake extracts was applied for manufacturing low salted Jeot-gal with sodium DL-malate and sodium nitrite as food preservatives. Due to antibacterial activity from Tricholoma matsutake extracts, MIC of sodium DL-malate and sodium nitrite were significantly reduced to 0.025 g/L and 0.25 g/L, respectively. As a result of this study, a premium low salted Jeot-gal can be developed with low concentration of food preservatives by adding Tricholoma matsutake extracts.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.279-286
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• 2005

The Opuntia ficus-indica var. saboten Makino (Cactus) is a tropical or subtropical plant, which is cultivated or grows naturally in Jeju island. It has been widely used as folk medicine for burned wound, edema and indigestion. In addition, its extract has been claimed to have several biological activities including anti-inflammation in oriental medicine. In this study, we examined the antimicrobial activities of the methanol extract of Opuntia ficus-indica var. saboten Makino. The extract showed a broad spectrum of antimicrobial activity against pathogenic bacteria, including antibiotics resistant bacteria (MRSA, R-P. aeruginosa, VRE) and Propionibacterium acnes, yeast, and fungi. The extract retained the activity after heat treatment for 15 min at $100^{\circ}C$ and $121^{\circ}C$ and after extended storage, up to 10 weeks storage period at $4^{\circ}C$ and $25^{\circ}C$, also stably retained its activity. It showed a better inhibitoring effect to the growth of E. coli than sodium benzoate did it at the same concentration. Addition of various salts or metal ions did not affect on its antimicrobial activity. Therefore, the antimicrobial characteristics of the extract can be applicable as a natural preservative and an antimicrobial agent for bacterial disease.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.168-174
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• 1998

The amount of D(-)-lactic acid in fermented dairy products is very important because the rate of metabolism of D(-)-lactic acid is lower than that of L(+)-lactic acid. The purpose of this study was to investigate the optimum condition during fermentation and storage of yogurt for the formation of isomers of lactic acid by Lactobacillus acidophilus NCFM. The production of acid was excellent at $37^{\circ}C$ of fermentation and the ratio of D(-)-lactic acid was also lower than that of other conditions such as $35^{\circ}C{\;}and{\;}40^{\circ}C$. Among shaking and non-shaking treatment under aerobic condition and anaerobic condition, non-shaking treatment under aerobic condition was the best condition at the production of acid and L(+)-lactic acid during fermentation. During storage at low temperature, a larger amount of L(+)-lactic acid was produced than at higer storage temperature.

• Korean Journal of Plant Resources
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• v.21 no.5
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• pp.352-356
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• 2008

This study was performed to investigate the antimicrobial effects of Origanum majorana L. ethanol extract against food-borne pathogens. The antimicrobial activity of Origanum majorana L. extract was determined using a paper disc method. The extract exhibited growth inhibiting activities in a concentration dependent manner on 10 species microorganisms. The extract of Origanum majorana L. showed the highest antimicrobial activity against Salmonella enteritidis. The growth inhibitory effects of Origanum majorana L. extract on food poisoning microorganisms were determined against Salmonella typhimurium and Listeria monocytogenes, gram negative and positive bacteria, respectively. The extract of Origanum majorana L. had strong antimicrobial activity against Salmonella typhimurium and Listeria monocytogenes at the concentration of $700 mg{\cdot}L^{-1}$. At this concentration, the extract of Origanum majorana L. inhibited the growth of Salmonella typhimurium and Listeria monocytogenes up to 60 and 36 hours, respectively. The results in the present study demonstrate antimicrobial effects of Origanum majorana L. ethanol extract against food-borne pathogens, suggesting that Origanum majorana L. could be an effective natural antibacterial agent in food.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.225-230
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• 1988

Emulsion stability, viscosity, and oil particle size of mayonnaise, prepared at various egg yolk contents, were investigated. With increasing of the egg yolk ratio, emulsion stability became stronger, viscosity became higher, and oil particle size became smaller. Freezing stability of mayonnaise containing below 6.5% egg yolk was reduced significantly. Referring to vibration separation, it was observed that stability of mayonnaise containing 2% and 3.5% egg yolk was very low and containing over 5% egg yolk was stable relatively. Viscosity of mayonnaise, stored at $-10^{\circ}C$, was reduced significantly during first 24hrs. and then levelled off. Oil particle size of mayonnaise, stored at $-10^{\circ}C$, became larger with increasing the storage time and the tendency to change was apparent in the sample containing below 6.5% egg yolk.

• Korean Journal of Food Science and Technology
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• v.3 no.2
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• pp.89-93
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• 1971

Microorganisms producing milk-clotting enzyme were isolated from 1,506 strains which were collected from soil on the various places of Korea, and from strains which were already identified. Dothiorella ribis was taken as a good strain producing milk-clotting enzyme. When it is cultured on wheat bran, the optimum experimental conditions for the production of milk-clotting enzyme were consequently obtained as follows: 1) $30{\sim}35^{\circ}C$ of temperature and 4.0 of pH. 2) $60{\sim]80%$ of cultivating water to the weight of wheat bran. 3) addition of $(NH_4)_2SO_4$ as a nitrogen source, $NaCl\;and\;KH_2PO_4$ as an inorganic salt, and 3% of sucrose as a carbon source. 4) four days for a period of cultivation.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1367-1372
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• 1998

The studies were carried out to investigative effects of Lithospermum erythrorhizon, Glycyrrhiza uralensis 3% (LG) with and without dipping of salted Chinese cabbage in 1% chitosan solution(LGDC) on fermentation of kimchi at $10^{\circ}C$ during 25 days. The pH and titratable acidity of kimchi with LG and LGDC were higher and lower, respectively, than that of control. Viable cells of total bacteria, lactic acid bacteria, Leuconostoc sp. and Lactobacillus plantarum in kimchi added with LG and LGDC were shown inhibitory effect about $1.6{\sim}2.1,\;1.2{\sim}2.9,\;0.8{\sim}2.2,\;0.7{\sim}1.6$ log10 cycle, respectively. Specially Leuconostoc sp. and L. plantarum was very inhibited than in control from 0 day. The sour taste of LG and LGDC added kimchi was changed more slowly than that of control during fermentation of kimchi. But flavor, color and overall acceptability did not show significant difference(P<0.05) between treatments. The shelf-life of LGDC added kimchi was extended over 10 days compared with control.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1275-1280
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• 1997

The possible use of tea catechins as natural preservatives for kimchi was investigated in this study. Tea catechins separated from tea leaves had antimicrobial activity against microorganisms related to kimchi fermentation, such as Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus brevis, Pediococcus cerevisiae, Streptococcus faecalis. The degree of antimicrobial activity of catechins were different among microorganisms; that is 2 mg/mL to Leuconostoc mesenteroides, Lactobacillus plantarum, and Pediococcus cerevisiae, 4 mg/mL to Streptococcus faecalis, and 5 mg/mL to Lactobacillus brevis; however, Saccharomyces cerevisiae can not be inhibited. The effect of tea catechins on retardation of kimchi fermentation was tested by measuring changes in pH and acidity. The changes of pH and acidity of baechu-kimchi and mul-kimchi were remarkably inhibited by adding the tea catechins at the level of 2 mg/g fresh baechu. These results suggest that the tea catechins can be successfully used for the extension of shelf-life of kimchi.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.149-158
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• 2021

Advances in food packaging play an important role in keeping food manufacturing and food supply safe. Food packaging facilitates the storage, handling, transportation and preservation of food, and also contributes to the minimization of food waste. On the other hand, food packaging materials have high production volumes, short usage times, and accelerate the occurrence of environmental problems related to waste. The circular economy has already been introduced to pursue sustainability through resource conservation and recycling, and to reduce waste and carbon emissions. By activating an eco-friendly economic system that minimizes resource depletion and environmental pollution, reducing, reusing, recycling and redesigning the goals of the circular economy will reduce the impact of food packaging on the environment. This review focused on the safety aspects of recycled food packaging as recycling is currently considered an important means of packaging waste management. Assessing the safety of recycled packaging is very important because recycling can increase the levels of potentially hazardous chemicals in packaging and in the food after they are migrated. Various food packaging materials such as plastic, paper and cardboard, aluminum, steel, and multi-material multi-layers packaging are commonly used, but only the recycling safety of plastic food packaging materials, which is the most used and has a significant increase in post-use problem, is discussed in this review.

• Journal of Life Science
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• v.21 no.3
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• pp.375-384
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• 2011

This study was performed to evaluate the antioxidant and antimicrobial activity of methanol extract from Rosmarinus officinalis L. and its fractions. The ethyl acetate fraction of rosemary had a higher antioxidant activity in both DPPH ($3.22\;{\mu}g/ml$) and ABTS ($5.05\;{\mu}g/ml$) compared to other extracts and fractions. Based on the results of the FRAP assay, the ethyl acetate fraction of rosemary showed a value of $5.9{\pm}0.3\;{\mu}M/{\mu}g$, and buthanol fraction and rosmarinic acid exhibited values of $4.8{\pm}0.2\;{\mu}M/{\mu}g$ and $5.1{\pm}0.1\;{\mu}M/{\mu}M$, respectively. Measurements of the antimicrobial activities of the extracts, fraction against gram positive, negative bacteria revealed that the methanol extract, hexane, ethyl acetate, and chloroform fraction of rosemary caused Staphylococcus aureus and Escherichia coli to form clear zones greater than 12 mm. Furthermore, the methanol extract and chloroform fraction showed high antibacterial activity, with inhibition zone exceeding 13 mm. The methanol extract and chloroform fraction of rosemary had broad antimicrobial spectrums and low MIC values. Therefore, methanol extracts of rosemary could serve as potential antibacterial agents to inhibit pathogen growth in food and hand sanitizers.