• Analytical Science and Technology
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• v.30 no.2
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• pp.57-67
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• 2017

This study was conducted to develop an analytical technique for determination of chlorite and chlorate concentrations in fresh-cut food and dried fish products by an ion chromatography/conductivity detection method using a hydroxide mobile phase. Deionized water was added to homogenized samples, which were then extracted by ultrasound extraction and centrifuged at high speed (8,500 rpm). Subsequently, a Sep-Pak tC18 cartridge was used to purify the supernatant. Chlorite and chlorate ions were separated using 20 mM KOH solution as the mobile phase and Dionex IonPac AS27 column as the stationary phase. Ethylenediamine was used as sample preservative and dibromoacetate was added to adjust for the disparity in extraction efficiencies between the food samples. The method detection limit) for chlorite and chlorate were estimated to be 0.2 mg/kg and 0.1 mg/kg, respectively, and the coefficient of determination ($r^2$) that denotes the linearity of their calibration curves were correspondingly measured to be 0.9973 and 0.9987. The recovery rate for each ion was 92.1 % and 96.3 %, with relative standard deviations of 7.47 % and 6.18 %, respectively. Although neither chlorite nor chlorate was detected in the food samples, the analytical technique developed in this study may potentially be used in the analysis of disinfected food products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.857-863
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• 2004

The effects of adipic acid on the growth of psychrotrophic kimchi lactic acid bacteria and on the fermentatation of mulkimchi were investigated. Four Leuconostoc and one Lactobacillus species were isolated from kinnchi fermented for 50 days at 6$^{\circ}C$. The growth inhibition rate of adipic acid on psychrotrophic kimchi lactic acid bacteria and control strain, Leuconostoc mesenteroides KCCM l1324, was gradually increased from 0.1% of adipic acid concentration and its growth inhibition rate on selected strains reached 90% at 0.4% addition of adipic acid. On the bases of these results, the Preservative effect of adipic acid on the fermentation of mulkimchi was investigated for 25 days at 1$0^{\circ}C$. The pH of mulkimchi containing adipic acid was lower than that of control mulkimchi at the beginning of fermentation. However, the pH of the control mulkimchi decreased rapidly and the pH is lower at the end of fermentation than that of all samples containing adipic acid. The control increased rapidly during fermentation at the acidity. Adipic acid inhibited the growth of several microorganisms in mulkimchi including Lactobacilli. The number of Lactobacilli in control mutkimchi increased rapidly at the beginning stage of fermentation and it decreased at the end stage due to lowering of pH. However, that of mulkimchi with adipic acid slowly increased. Addition of 0.2% ethyl alcohol showed increase of preservative effect of 0.1% adipic acid in mulkimchi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.2
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• pp.244-248
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• 2015

We explored the efficiency of natural antibacterial agents used to enhance the self-life and sensory properties of shucked and packed Pacific oyster Crassostrea gigas, which are in high demanded. First, we screened natural resources exhibiting antibacterial activity against food spoilage and pathogenic bacteria. Of theses, ignited oyster shell powder (IOS) and the natural food preservative, lactic acid bacteria fermented powder (LBF), were selected for further study considering the efficacy, mass production, and cost. The addition of 0.1% IOS (W/V) and 0.5% LBF (W/V) to shucked and packed oyster optimally extended the shelf-life without affecting the sensory evaluation. The results obtained in this study will provide a clue to enhance self-life in raw oyster products.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.135-139
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• 2006

Most bacteria form biofilm as self-defence system, making efficient food sanitization, preservation, and instrument washing more difficult. Biofilm formation of Salmonella, E. coli, B. cereus, and S. aureus was observed during 24 hr food preservations by performing microtiter plate and glass wool assays. Most cells formed biofilm and attached onto glass wool. When biofilm formation and injury were analyzed on the microtiter plate, 10 and 20% acid-injured E. coli and S. aureus, respectively, 30-50% cold temperature $(4^{\circ}C)-injured$ B. cereus and E. coli, and 30-55% 6% sodium chloride solution-injured Salmonella showed significant biofilm formation. Results indicate biofilm formation level differed within species depending on type of stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1640-1646
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• 2008

In the current food sanitation regulation, food additives are under controlled by the Food Code. The naturally derived preservatives such as benzoic acid and propionic acid can be naturally carried over or produced as metabolites during manufacturing process such as fermentation. To monitor naturally formed benzoic acid and propionic acid levels, a total of 145 samples were classified into berries (prune, cranberry), functional foods (propolis liquid, ginseng product), vinegars (vinegar-based drink, vinegar beverage, vinegar), and salted and pickled products (olive, pickled cucumber, salted/pickled product) and analyzed by HPLC-PDA and GC-FID. From the results, benzoic acid and propionic acid were each detected and identified in 144 samples and 64 samples respectively. The amount of benzoic acid ranged from $4.1{\sim}478.4\;ppm$ in cranberry, from $49.7{\sim}491$ in propolis liquid, and from $2.5{\sim}10.2\;ppm$ in ginseng, and other tested samples contained very small quantity. Also, the amount of propionic acid ranged from $179.8{\sim}951.9\;ppm$ (av. 553.6 ppm) in vinegar (persimmon vinegar 100%), which was the highest level among fermented foods, from $13.7{\sim}247.0$ ppm in propolis liquid, from $2.0{\sim}180.7\;ppm$ in vinegar-based drink, and from $1.6{\sim}76.6\;ppm$ in olive. Vinegar beverage and pickled cucumber each showed 24 and 18 ppm of propionic acid; in contrast, propionic acid was not detected in prune, cranberry, ginseng, and picked/salted products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.1001-1007
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• 1994

In order to develop a natural food preservative, dried salviae miltiorrhizae radix (Salvia miltiorrhiza) was extracted with several solvents, and then antimicrobial activity was investigated. The optimum extracting condition for the antimicrobial sustance from the sample, minimal inhibitory concentration (MIC) of the extracted substance against microorganisms were also examined. Antimicrobial activity of the initial ethanol extract from the sample was the strongest compared to those of other solvent extracts such as n-hexane, acetone, butanol, methanol and water. the optimum extractingcondition for antimicrobial substance from the sample was shaking extraction for 2 hours at room temperature incase that 10 volumes of absolute ethanol was added to crushed Saliva Miltiorrhiza. The ethanol extract had strong growth inhibition activity against Gram-positive Bacteria (MIC, 3.13-50$\mu\textrm{g}$/ml) such as B. cereus, B, subtilis, L. minocytogenes, S. aureus, Sc. Mutans. Among Grampositive bacteria tested, Bacillus species was the most susceptibile to the extracted substance. The antimicrobial activity of the ethanol extract from the sample was weak to Gram -negative bacteria yeasts, for example MIC for Gram-negative bacteria and yeasts was 0.8mg/ml and 0.4-0.8mg/ml , respectively.

• Korean Journal of Plant Resources
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• v.30 no.6
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• pp.670-678
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• 2017

Persimmon seeds contain considerable amounts of minerals, amino and organic acids, natural antioxidants and phenolic compounds. The objective of this study was to investigate quality characteristics and antioxidant potential of Korean persimmon seeds. The pH (4.88-4.94), color values, contents of minerals, free amino acids, organic acids, and phenolic compounds and DPPH free radical scavenging potentials of persimmon seed extracts significantly (p < 0.05) varied with the genotypes. This study showed that the seeds could be used as a source of different mineral elements (47.14-85.07 mg/kg) without any measureable amount of heavy metals such as arsenic, cadmium, lead and mercury. Similarly, considerable amounts of organic (1550.13-2413.08 mg/kg) and essential amino (50.85-54.03 mg/kg) acids and total phenolic compounds ($1227.91-1307.78{\mu}g$ gallic acid equivalent/g) were also found in the seed extracts, indicating their potential food value as a natural antioxidant. Results of the present study imply that prethanol-A, a food preservative, can be used as an effective extraction to obtain the minerals, organic and free amino acids, and phenolic compounds from the persimmon seeds, which possess a big potential to be commercially used in food, cosmetic and pharmaceutical industries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.456-461
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• 1997

Sodium lactateand sodium citrate, traditional food preservatives, were added to extend the shelf-life of the loow-salted Myungran-jeot, and various chemical and microbiological analyses were carried out with Muungran-jeot, and various chemical and microbiological analyses were carried out with Myungran-jeot femented at 1$0^{\circ}C$. pH was decreased in the beginning stage of fermentation and then increased, whereas the content of lactic acid was increased during fermentation. But, lactic acid production of the low-salted Myungran-jeot with preservative were lower than control. The NH$_2$-N content of the low-salted Myungran-jot with sodium citrate was increased in the beginning of fermentation and then decreased. Sodium citrate inhibited the productions of VBN and TMA during the fermentation of Myungran-jeot, whereas sodium lactate inhibited the productions of VBN and TBA. Sodium lactate inhibited the growths of proteolytic bacteris and fungi. The estimated shelf-lives of the Myungran-jeot with control, sodium lactate, and sodium citrate were about 11, 13, and 13 days, respectively.

• Korean Journal of Food Science and Technology
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• v.4 no.1
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• pp.24-28
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• 1972

Synthetic food preservatives were analysed in foods collected in Seoul area on Aug. 10, 1971. Sorbic acid, benzoic acid, dehydroacetic acid and butyl p-hydroxybenzoate were determined by the simultaneous gas chromatography using FID at $200{\circ}C$ and a column of Chromosorb W coated with 5% $DGS{\sim}1%\;H_3PO_4$. The recovery rates of each preservative were from 76.7% to 96.3%. The calibration curves show linearity within a range from 0.3 to $2.5{\mu}g$ of standard preservatives. The results obtained were as follows: 1) Benzoic acid was used as well as butyl p-hydroxybenzoate in soy. 2) Sorbic acid was not found in soy. 3) From all breads and biscuits benzoic acid was found as trace. 4) Detected preservatives were below the range of permitted limit. 5) From 2 soy among 15 samples dehydroacetic acid was found.

• Biomedical Science Letters
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• v.26 no.4
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• pp.383-388
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• 2020

Ingestion of food contaminated with microorganism, if not always, could lead to severe health problem. Preservatives has been added to food to prevent food from being contaminated with microorganism. But, these have potential to threaten the health. Therefore, much effort has been taken to find the safe materials showing the anti-microbial activity. In this study, we investigated the anti-bacterial activity of Oenothera lamarckiana aerial part extract against eight bacteria strain. In paper disc assay, extract inhibited the growth of Staphylococcus aureus, Methicillin-resistant S. aureus, Bacillus cereus and Shigella dysenteriae at 200 μg/disc, but not against Escherichia coli, E. coli O157:H7, Salmonella Typhi and S. enteritidis. Minimum inhibitory concentration (MIC) against Staphylococcus aureus, Methicillin-resistant S. aureus, Bacillus cereus and Shigella dysenteriae is 250, 250, 500 and 500 μg/mL, respectively. Compared with reported MIC of other plant resources, O. lamarckiana aerial part extract showed the relatively high anti-bacterial activity. O. lamarckiana aerial part could be suitable for the preservative development. But, it still remains to be studied to evaluate safety and so on.