• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.453-455
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• 1987

Swollen commercially canned grapes and peaches were collected to investigate the microorganisms involved in their spoilage. 6 of 52 grape and 19 of 23 peach samples were found to be spoiled by microorganisms. Yeasts were the only spoilage microorganisms of canned grapes with Saccharomyces cerevisiae as the leading spoilage yeast. Yeasts and bacteria were found from spoiled canned peaches. S. cerevisiae and Torulopsis stellata were the most important spoilage yeasts of canned peaches. Lactic acid bacteria, belonging to genera of Lactobacillus and Leuconostoc, were the most frequently found spoilage bacteria. Only one spore-forming bacterium, Bacillus licheniformis, was involved in the spoilage of canned peaches.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.260-263
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• 2006

In this study, we investigated the antimicrobial effect of 14 different herbal petal extracts on various foodborne and food spoilage bacteria. Herbal petal extracts were prepared with 70% ethanol followed by sequential hexane, chloroform, ethyl acetate, n-butanol, and water fractionation. Antimicrobial activity was highest in the ethanol fraction from roselle (Hibiscus sabdariffa L.) petals as determined by the paper disc method. The roselle ethanol extract retarded the growth of food spoilage bacteria in kimbap (rice rolled in dried laver). Foodborne microorganisms (e.g. Bacillus cereus and Clostridium perfringens), on the other hand, were most efficiently inhibited by the ethyl acetate fraction of the roselle petal extract as determined by growth inhibition curves. Our study shows that roselle petals harbor antimicrobial activity against foodborne and food spoilage microorganisms. The critical ingredient is highly enriched in the ethyl acetate fraction of the extract.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1243-1252
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• 2009

User-friendly software was developed to determine the shelf-life of perishable Korean seasoned side dishes in real time based on growth models of spoilage and pathogenic microorganisms. In the program algorithm, the primary spoilage and fastest-growing pathogenic organisms are selected according to the product characteristics, and their growth is simulated based on the previously monitored or recorded temperature history. To predict the growth of spoilage organisms with confidence limits, kinetic models for aerobic bacteria or molds/yeasts from published works are used. Growth models of pathogenic bacteria were obtained from the literature or derived with regression of their growth rate data estimated from established software packages. These models are also used to check whether the risk of pathogenic bacterial growth exceeds that of food spoilage organisms. Many example simulations showed that the shelf-lives of the examined foods are predominantly limited by the growth of spoilage organism rather than by pathogenic bacterial growth.

• Journal of Food Hygiene and Safety
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• v.15 no.1
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• pp.36-40
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• 2000

This study was carried out to know the active faction of Dryopteris rhizoma on antimicrobial activity against some food spoilage microorganisms. Also, antimicrobial activities were investigated for the aqueous and ethanolic extracts of four herbs such as Teminaliae fructus, Eugeniae flos, Salviae miltior-rhizae radix and Dryopteris rhizoma. Antimicrobial activities of three herbs except for Terminaliae fructus showed higher activities in 75% ethanolic extracts than in aqueous extract. Ethanolic extract of Dryopteris rhizoma showed the highest antimicrobial activity among extracts of four herbs. Antimicrobial activity intensities of solvent fractions of Dryopteris rhizoma extracted by 75% ethanol were order to CHC1$_3$fraction>EtOAc fraction >BuOH fraction>$H_2O$ fraction. The CHC1$_3$, EtOAc and BuOH fractions also inhibited growth of food spoilage microorganisms as the concentration increased, respectively. In case of EtOAc fraction, 1000 ppm of fraction almost inhibited completely the growth of microorganisms tested.

• International Journal of Human Ecology
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• v.7 no.1
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• pp.145-153
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• 2006

Hwangryeon (Coptidis rhizoma) was extracted by methanol and its antimicrobial activities against food spoilage and foodborne disease microorganisms were investigated by the paper-disc method. The microorganisms used in this experiment included 5 species of bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella pneumoniae, and Staphylococcus aureus) and 3 species of fungi (Fusarium solani, Aspergillus flavus, and Penicillium citreonigrum). The Hwangryeon extract showed antimicrobial effect against P. aeruginosa, S. aureus, S. typhimurium, and K. pneumonia. The minimum inhibitory concentration on S. aureus, S. typhimurium, and K. pneumoniae was 300 mg/mL, but on P. aeruginosa it was 200 mg/mL. In the methanol extracts from Hwangryeon, 190 compounds were separated by GC/MS. The extraction yields of phenols, furans, alcohols, acids and esters, ketones, and miscellaneous compounds were 28.10%, 2.67%, 1.79%, 12.89%, and 2.35%, respectively. The phenolic compounds, generally understood to be an antimicrobial active substance, was measured at 28.10%, a relatively remarkable amount.

• Journal of Microbiology and Biotechnology
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• v.33 no.4
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• pp.419-429
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• 2023

Ultraviolet C (UV-C, 200-280 nm) light has germicidal properties that inactivate a wide range of pathogenic and spoilage microorganisms. UV-C has been extensively studied as an alternative to thermal decontamination of fruit juices. Recent studies suggest that the efficacy of UV-C irradiation in reducing microorganisms in fruit juices is greatly dependent on the characteristics of the target microorganisms, juice matrices, and parameters of the UV-C treatment procedure, such as equipment and processing. Based on evidence from recent studies, this review describes how the characteristics of target microorganisms (e.g., type of microorganism/strain, acid adaptation, physiological states, single/composite inoculum, spore, etc.) and fruit juice matrices (e.g., UV absorbance, UV transmittance, turbidity, soluble solid content, pH, color, etc.) affect the efficacy of UV-C. We also discuss the influences on UV-C treatment efficacy of parameters, including UV-C light source, reactor conditions (e.g., continuous/batch, size, thickness, volume, diameter, outer case, configuration/arrangement), pumping/flow system conditions (e.g., sample flow rate and pattern, sample residence time, number of cycles), homogenization conditions (e.g., continuous flow/recirculation, stirring, mixing), and cleaning capability of the reactor. The collective facts indicate the immense potential of UV-C irradiation in the fruit juice industry. Existing drawbacks need to be addressed in future studies before the technique is applicable at the industrial scale.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.200-204
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• 1991

Certain parts of 36 kinds of plant were extracted by 75% ethanol and water. The extracts were tested their microbial inhibition activities against several food spoilage microorganisms, Bacillus subtilis, Lactobacillus plantarum, Leuconostoc mesenteroides, Pseudomonas fluorescens, Bacillus cereus and Saccharomyces cerevisiae. The ethanol extract of amur cork was shown inhibitory effect on all 6 species of the microorganisms tested. Chinese pepper, sesame cake, gromwell and oak were on 5 species except S. cerevisiae or P. fluorescens and bamboo leaves, lycopi herba, paulownia and rigida were on 4 species. In general amur cork exhibited the strongest inhibition with a few exceptions on certain species. By disc diffusion method, the ethanol extract of leaf mustard showed the highest inhibition effect on B. subtilis, amur cork on L.plantarum, L. mesenteroides and B. cereus, and amur cork and gallnut on P. fluorescens. Mostly the ethanol extracts in comparison with water extracts showed higher inhibition in most of plants but a few exhibited higher in water extracts.

• 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.

• Food Science and Preservation
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• v.14 no.3
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• pp.323-327
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• 2007

Moderate consumption of maesil(Prunus mune) was associated with pharmaceutical and physiological effects on human health. The object of this study was to determine the inhibitory effects of Prunus mune extracts(PME) on food spoilage microorganisms. PME was found to have an antibacterial effect on Colletotrichum fragariae. The hydrophilic fractions of PME showed more effective inhibition than did the hydrophobic fractions. In addition, the hydrophilic fractions of PME seemed to inhibit(12-40%) metabolic enzymes related to energy production, including glucose-6-phosphate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, and hexokinase. Our data suggest that hydrophilic components of PME might control food spoilage microorganisms because of suppression of membrane enzymatic function.

• Journal of Life Science
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• v.8 no.6
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• pp.648-653
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• 1998

The development of natural food preservatives instead of chemical synthetic food preservatives is world wide inte-rest. Authors already investigated that cinnamon bark extract revealed antimicrobial activity against general spoilage microorganisms of food especially its acitivity was stronger against molds than against bacteria. In this paper, authors examined the mirobial flora from the spoiled fish meat paste products and also checked the possibility of cinnamon bark extract food preservative for prolong the shelf life of the fish paste product and breads. The predominat bacteria was Bacillus sp. as about 98% of the total microorganisms isolated from unpacked or packed spoiled fish meat paste products. While molds and yeast are not detected from the vacuum packed products. The MIC(minimum inhibitory concentration) of cinnamon bark extract against the isolated spoilage bacteria and molds was 160~640$\mu\textrm{g}$/$m\ell$ and 40~80$\mu\textrm{g}$/$m\ell$, respectively. When the diluted cinnamon bark extract (the extract : ethanol=1 : 3) was sprayed on the surface of fried fish meat paste product, molds growth was delayed by 2 days at room temperature. The shelf lifes of sandwich and glutinousrice bread which surface sprayed with the diluted extract(1 : 1) was extended by 5 and 7 days, respectively.