• Proceedings of the PSK Conference
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• 2001.10a
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• pp.147.2-148
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• 2001

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.6
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• pp.810-817
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• 2023

Oysters are a highly consumed seafood throughout Korea, but they have a short shelf life because they support rapid microbial growth due to their of high moisture content and fragile muscle tissue. We examined natural food additives including lactic acid bacteria fermentation powder, rosemary extract, and lemon juice for their ability to preserve raw oyster Crassostrea gigas quality. Samples were stored at 4℃, and microbiological and physicochemical analyses were conducted. Among the natural additives tested, lemon juice was the most effective. Lemon juice was thus applied at different concentrations (50-300 ppm) to quantitatively assess its effect on total viable cell count, pH, glycogen, soluble protein, and turbidity. 200 ppm was confirmed to be optimal, and is projected to extend shelf life by 2 days compared to the control group.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.121-125
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• 2001

For the probiotic feed production, aerobic liquid fermentation of pulverized food wastes was attempted with a yeast Kluyveromyces marxianus. After grinding finely, optimal fermentation conditions of the substrate was investigated by shaking culture. The most active growth of the yeast was shown at solid content of 10%. The proper addition of urea(0.5g/l), o-phosphate(0.4g/l), molasses(4g/l), and yeast extract (1g/1) increased cell growth rate and viable cell count. For optimizing, the nutrients were all added to substrate and fermentation was carried in 2 litre jar fermenter. For the stimulation of hydrolyzing enzyme excretion, mixed culture with Aspersillus oryzae was also conducted. In 12 hours of fermentation, viable cell count of the yeast Kluyveromyces marxianus amounted to the number of 1.4 $\times$10$^{10}$ /1 in the culture medium.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1994.06a
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• pp.17-22
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• 1994

Food additives are minor components which are used to enhance nutritive or sensory values, and to improve shelf life of foods. In foods, natural additives are preferred over artificial or synthetic materials because of concern on food safety. Many biotechnological techniques have been applied to the production of food additives since the biotechnology has been utilized to prodyce many flavor components such as glutamate, 5'-nucleotides, esters, 2,3-bytadione, pyrazines, terpenes, and lactones. Natural flavors, fragrances, sweetners, and colorants can be produced by plant cell culture. Many lactic acid bacteria produce bacteriocins such as nisin or diplococcin. These bacteriocins are used as safe preservatives in foods and many researches on the improvenment of bacteriocin productivity by genetic engineering are in progress.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1994.06a
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• pp.41-49
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• 1994

The meanings, classification, and regulatory status of 'natural food colorants' are discussed. Nowadays the technological advances for processing Cochineal color is flourishing here and aboard, makes highly concentrated products (e.g., 95% Carminic acid) is comercially available. Application of carminic acid for a food system needs target-specific formulation, mixing with alumn, tartaric acid, and other salts to stabilize the color hue in food system. On the other hand, carmine, the aluminium-lake of carminic acid, is more convenient product to be used and would give more strong color. Of these reasons Carmine is much popular product than Cochineal extract in Western and European countries. We insist that carmine should be also certified as natural colorant together with Cochineal extract in Korea. Authors expect that several kinds of anthraquinone colorant (Lac and Kermes) would be introduced in Korean market in near furture.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.361-364
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• 2002

This study was performed to establish a simple and accurate method for the determination of oxygen that is a processing aid in various beverage. The quantitative determination of dissolved oxygen (DO) contents in 30 cases of samples were performed by traditional titration method and polarography. As a result of the study, the analysis of DO contents in fruit-extract beverages containing oxygen by titration method was time consuming and large sample volumes were needed. Besides, serious interferences with compounds such as hydroxylamine and nitric oxide were observed, leading to false response. Although the polarography is easily affected by $H_2S$, proteins, and various organic compounds, it is a simple and practical method that provides inexpensive and relatively rapid analysis. The polarography is best suited to the routine determination of DO in a large number of samples and it is expected that the polarography can directly be applied to the quality control of the beverages containing added oxygen. The analysis results of DO contents in various fruit-extract beverages with oxygen and without oxygen were as follows: 23.10 ppm to 32.60 ppm for various frutis extract beverages with oxygen, 0.70 pp to 2.54 ppm for mixed beverages without oxygen, 7.63 ppm to 8.28 ppm for drinking water.

• Food Science of Animal Resources
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• v.43 no.2
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• pp.319-330
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• 2023

Some preservatives are naturally contained in raw food materials, while in some cases may have been introduced in food by careless handling or fermentation. However, it is difficult to distinguish between intentionally added preservatives and the preservatives naturally produced in food. The objective of this study was to evaluate the minimum inhibitory concentration (MIC) of propionic acid, sorbic acid, and benzoic acid for inhibiting food spoilage microorganisms in animal products, which can be useful in determining if the preservatives are natural or not. The broth microdilution method was used to determine the MIC of preservatives for 57 microorganisms. Five bacteria that were the most sensitive to propionic acid, benzoic acid, and sorbic acid were inoculated in unprocessed and processed animal products. A hundred microliters of the preservatives were then spiked in samples. After storage, the cells were counted to determine the MIC of the preservatives. The MIC of the preservatives in animal products ranged from 100 to 1,500 ppm for propionic acid, from 100 to >1,500 ppm for benzoic acid, and from 100 to >1,200 ppm for sorbic acid. Thus, if the concentrations of preservatives are below the MIC, the preservatives may not be added intentionally. Therefore, the MIC result will be useful in determining if preservatives are added intentionally in food.

• The Korean Journal of Food & Health Convergence
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• v.10 no.2
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• pp.13-17
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• 2024

Oxygen is necessary to sustain life, but reactive oxygen species (ROS) produced by oxygen metabolism can cause mutations and toxicity. ROS can damage cellular macromolecules, leading to oxidative stress, which can accelerate cell death and aging. ROS generated in food affect the taste, color, and aroma of food, and high levels of ROS in meat can cause spoilage. Superoxide dismutase (SOD) plays an important role in scavenging ROS in food and reducing their toxicity to organisms. SOD exerts its antioxidant effect by catalyzing the breakdown of O₂-• to H₂O₂. As a natural antioxidant, SOD has the ability to regenerate and maintain its activity over a long period of time without depletion, unlike chemical antioxidants that may have side effects or stability issues. This antioxidant effect of SOD has great potential in a variety of industries, and in the food industry it can be utilized to improve product quality and provide safe and healthy products to consumers. By disrupting the SOD2 and SOD3 genes in Candida albicans, we studied the effects of SOD2 and SOD3 genes on the antioxidant system, suggesting its potential as a natural antioxidant.

• Journal of the Korean Society of Food Culture
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• v.34 no.1
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• pp.14-22
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• 2019

This study examined the effects of 'Dietary education for children's health UP' (DECHUP) on the changes in knowledge, attitudes, and practice (KAP) of nutrition and food safety in $5^{th}$ grade elementary school students in Incheon. The DECHUP program was conducted from May to October 2018 and consisted of education and activities focusing on the children's levels of understanding. Data were collected before, immediately after, and 6 weeks after DECHUP using the same method. All data were analyzed using SPSS ver 20.0. The level of knowledge and attitudes of the subjects to nutrition and food safety was significantly higher after than before DECHUP, but the attitude of boys did not show any significant difference after 6 weeks. Although there were no significant differences in the behavior for nutrition in the practice of the subjects, there were significant positive changes in the behavior of food safety. The higher the satisfaction of DECHUP, the more positive the change in knowledge, and the more positive the attitude and practice behaviors. Therefore, DECHUP has positive effects on the KAP of the subjects, and it will be helpful for elementary school students to form desirable eating habits if it can be carried out periodically and continuously.

• Journal of Life Science
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• v.23 no.5
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• pp.637-642
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• 2013

This study was performed to evaluate the rodent repellency and antimicrobial activity of natural oils. Thirteen natural essential oils were evaluated for repellent efficacy against rodent feed intake suppression activity. Salvia sclarea (sage), Cinnamomum zeylanicum (cinnamon) Cymbopogon citratus (lemon grass), and Syzygium aromaticum (clove) showed the best repellent efficacy among tested natural oils. Antimicrobial activity against Gram-negative (four strains) and Gram-positive (four strains) bacteria were evaluated using four natural oils, which showed high efficacy on the rodent repellent test. Syzygium aromaticum showed antimicrobial activity against all tested bacteria and Cymbopogon citratus, Cinnamonum zeylanicum, and Salvia sclarea showed antimicrobial activity against some tested bacteria.