• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.215-221
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• 2006

This study focuses on investigating the effect of porosity-controlled earthenware on fermentation of kanjang, Korean soy sauce. Porosity of fermentation vessel was controlled by changing the mixing ratio of raw soils at manufacturing earthenware. Earthenwares contented 0%, 40% and 60% of the mixture of red brown soil and powdered soil (1 : 1), respectively. The more contents of the mixed soil, the more porosity in earthenware. During fermentation of kanjang in porosity-controlled earthenwares at $30^{\circ}C$ for 4 months, physical, chemical, microbiological and sensory quality attributes were monitored. Compared to other containers, kanjang in the earthenware that had 0% mixed soil showed less water loss, salt content and pH. It also produced higher total acidity, protease activity, total nucleotide, and microbiological changes which included total aerobic bacteria, lactic acid bacteria and yeast. Total nitrogen and free amino acids in kanjang did not show the consistency with the mixed soil contents of fermentation containers, which may take more effect of other factors as water loss than the porosity of vessels. However, the percentage of glutamic acid in total free amino acids was a little higher in the earthenware that had 0% of mixed soil than other containers. These positive physicochemical, microbiological changes also resulted in higher sensory quality.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.369-376
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• 2017

Maturation of distilled spirit can generate diverse flavors and tastes. Rice Soju was matured in oak casks (MSO) and stainless steel containers (MSS) for one year at ambient temperature. Ipguk (Aspergillus luchuensis) and Saccharomyces cerevisiae Y88-4 were used, and reduced pressure ($110{\pm}20Torr$) distillation was applied to brew Soju. Acidity and conductivity were increased in both MSO and MSS. MSO reduced alcohol content (from 43 to 40%) and volume (from 18,000 to 12,730 mL), and significantly altered yellowness (from 0.2 to 30.2). Furthermore, MSO increased the isoamyl alcohol (from 276.7 to $339.2{\mu}g/mL$) and isobutyl alcohol (from 122.3 to $144.2{\mu}g/mL$) content. Gas chromatography-mass spectrometry was used to detect volatile compounds in Soju, which included 20 esters, 7 alcohols, 2 acids, and 5 miscellaneous compounds. Oak lactone was detected only in MSO and was considered as a specific flavor component associated with oak maturation. Thus, maturation materials contribute to the physicochemical property of distilled spirits.

• Food Science and Preservation
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• v.16 no.4
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• pp.499-505
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• 2009

Quality changes in fresh-cut potatoes during storage at $4^{\circ}C$ after treatment with low-temperature blanching and antibrowning agents were studied. Fresh-cut potatoes were treated by dipping for 1.5 min in a browning inhibitor solution containing 0.5% (w/v) ascorbic acid, 0.5% (w/v) citric acid, 0.5% (w/v) sodium chloride, 0.1% (w/v) trehalose, and 0.005% (w/v) biotin, at $60^{\circ}C$, with subsequent cooling for 1.5 min and storage at $4^{\circ}C$. The browning properties of fresh-cut potatoes were examined by measurement of polyphenol oxidase (PPO) activity and total phenolic content. Changes in quality attributes over a 14-day period were assessed in terms of titratable acidity, pH, water-soluble solid level, and gas analysis at $4^{\circ}C$. During storage, PPO activity increased, with the lowest activity seen after about 7 days of storage. Treatment with antibrowning solution at $4^{\circ}C$ increased visual sensory attributes during storage. Low-temperature blanching in distilled water more effectively inhibited browning compared with exposure to browning inhibitor solution, as assessed after 7 days of storage. Fresh-cut potatoes respired aerobically after different treatments during storage at $4^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.277-283
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• 2005

A plasticizer is a substance which is added to a material to improve its processability, flexibility and stratchability. Phthalates and adipates are the most frequently used plasticizers of poly(vinyl chloride) (PVC). However, they can migtate into food from PVC food packaging, and some of them are especially suspected as endocrine disruptors. In this study, Simultaneous analysis of 13 phthalates and 9 adipates were carried out by dual-column gas chromatography system equipped wi two FID detectors for rapid confirmation and quantification. The Proposed method was validated with > 0.993 of linearity in the ranges of 10-500 mg/l, < $3.5\%$ RSD of reproducability in 10 inter-days sample preparations, and > $98.1\%$ of recoveries for all the plasticizers. DEHA was detected in all the 3 PVC wraps at levels of 176.9-198.5mg/g. Among the 51 samples of PVC gaskets, the targeted plasticizers were detected in 41 samples. Of these plasticizer detected samples,40 contained DIDP at the levels of 157.3-374.7 mg/g and one contained DMP at the levels of 165.6 mg/g. Also, some plasticizers were detected in other packaging materials such as PET, PP, PE, Pulp. But it might be attributed to contamination in manufacturing.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.81-86
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• 2015

The purpose of our paper was to investigate the migration level of 4,4'-MDA(4,4'-methylenedianiline), 2,4-TDA(2,4-toluenediamine), aniline, acrylonitrile and methylmeth acrylate from plastic cookwares into food simulants and to evaluate the safety of each monomers. The test articles for monomers were PA (polyamide) items for 4,4'-MDA, 2,4-TDA and aniline, PU (polyurethane) items for 4,4'-MDA, ABS (acrylonitrile-butadiene- styrene) items for acrylonitrile, and acrylic resin items for methylmethacrylate. All the article samples of 321 intended for contact with foods were purchased in domestic market. 4,4'-MDA, 2,4-TDA and aniline were analyzed by LC-MS/MS (liquid chromatography -tandem mass spectrometer), acrylonitrile by GC-NPD (gas chromatography-nitrogen phos phorus detector) and methyl methacrylate by GC-FID (gas chromatography-flame ionization detector). The migration level of monomers were within the migration limits of Ministry of Food and Drug Safety (MFDS). As a result of safety evaluation, our results showed that the estimated daily intake (EDI, mg/kg bw/day)s were $2.39{\times}10^{-9}$ and $1.20{\times}10^{-9}$ for 4,4'-MDA and 2,4-TDA of PA, $4.32{\times}10^{-9}$ for acrylonitrile of ABS and $2.27{\times}10^{-7}$ for methylmethacrylate of acrylic resin. Reference Dose (RfD, mg/kg bw/day) of acrylonitrile and tolerable daily intake (TDI, mg/kg bw/day) of methacrylate were established respectively as 0.001 by EPA (US Environmental Protection Agency) and as 1.2 by WHO (World Health Organization). When comparing with RfD and TDI, the EDIs of acrylonitrile and methylmethacrylate accounted for $4.32{\times}10^{-4}%$ and $1.89{\times}10^{-5}%$ respectively.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.232-236
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• 2005

This study was performed to find out the patterns of Listeria spp. contamination during Kimbab preparation at the specialized restaurants. Samples were collected from ingredients, containers, equipments, and environments from two Kimbab restaurants from July through September, 2004. Isolation rate of Listeria spp. was $43.2\%$ among 264 samples. Strains isolated were Listeria innocua $35.9\%$, L. murrayi $6.8\%$, and L. grayii $0.3\%$. No L. monocytogenes was detected. Contamination level of ingredients, containers, equipments, and Kimbab sampled during afternoon was all significantly higher than the samples collected during morning(P < 0.05). The most influencing factor of contamination was improper handling or no disinfection procedures during Kimbab preparation. Safety controls are recommended as follows; prevention of cross-contamination during ingredients Preparation, temperature control for ingredients and Kimbab during holding, cleaning and disinfection of chopping boards and knives during preparation processing, and frequent changes of disposable gloves. Kimbab restaurants should recognize the importance of safety control using the Good Hygienic Practices.

• Food Science and Preservation
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• v.13 no.2
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• pp.234-240
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• 2006

The purpose of this study was to evaluate microbiologically cooking utensils, equipment employees, and environment in 12 large Korean, Western, Chinese, and Japanese restaurant. Microbiological testing was conducted for pathogens including E. coli, Samolnella, L. monocytogenes, S. aureus, E. coli O157:H7, V. parahaemolyticus, B. cereus, and Y. enterocolitica as well as total plate count and coliforms. The results showed cooking water and drinking water in some Korean restaurants and drinking water in some Western and Japanese restaurants were unsatisfactory, especially, barley tea, which was cooled after being boiled, was unsatisfactory. Most cooking utensils such as knives, cutting boards, kitchen towels, tongs, and basket had total plate and coliforms count in excess of standards, and knives and cutting boards at some Chinese restaurant had E. coli. At some restaurant, S. aureus was found on some food worker's hands. Also, the total plate count of the air showed a high count around worktables, inside the refrigerator, and in the kitchen in most restaurants. These result suggest that sanitation needs improvement in the environments in these foodservice establishment.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.3_4
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• pp.107-112
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• 2007

The effect of microwave heat to retort pouches and microwavable packages was examined. 186 products were collected, but packages were consisted of five package materials such as PET, Aluminum foil, Nylon, EVOH, and polypropylene. The results showed that all packages did not exceed the limits of current packaging regulation on consumption weight of $KMnO_4$, TDI(Toluene diisocyanate), and Caprolactam. Safety control on heat resistant packages considered satisfactory, but investigation on new substances should be continued for preventing any possible migration problems of packaged foods.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.383-395
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• 2014

When we investigated seed infestation by fungal pathogens from 51 varieties in 9 crops, the contamination rate of rice and sesame seeds was high. Therefore, to control seed-borne diseases, we obtained extracts from commercial products of Kimchi, Gochujang, Doenjang, Ganjang, Makgeolli and Tohajut and their suppressive effects against seed-borne diseases were studied. In addition, bacterial strains were screened to control rice seed-borne diseases in vitro and in vivo. Among forty food extracts, eleven food-extracts suppressed incidence of seedling rots in vitro and five food extracts increased 8-33% of healthy seedling in the greenhouse. Among 218 isolates from 40 fermented foods, 43 isolates showed high antifungal activity against seven fungal pathogens. When we tested 43 isolates for the reduction of rice seed borne disease, 32 isolates were able to reduce the rice seed borne disease. Among 32 isolates, 17 isolates reduced significantly seedling rot and increased healthy seedlings, the other isolates except for Kc4-2 and Mkl 2-2 increased shoot emergence and the percentage of healthy plants. Thirty isolates with high antifungal activity and suppressive effect against rice seedling rots were identified by 16S rRNA sequencing. Twenty one of thirty isolates were identified as Bacillus spp. Three isolates from Makgeolli were identified as Saccharomyces cerevisiae. B. amyloliquifaciens were isolated from six Korean traditional fermented foods except for Ganjang. B. amyloliquifaciens were majority in the effective bacterial population of Gochujang and Jutgal. Relatively diverse Bacillus species including B. subtilis, B. pumilus, and B. amyloliquificiens were isolated from Kimchi. The selected effective microorganisms from Korean fermented foods founded to be effective for controlling seed-borne diseases of rice in vitro and in the greenhouse. We think that Korean fermented foods and their useful microorganisms can be used as biocontrol agents for suppressing rice seed-borne diseases based on above described results.

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.95-101
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• 2024

In this study, we investigated the migration level of items specified in the Korean Standards and Specifications for Utensils, Containers, and Packages (Ministry of Food and Drug Safety Notification) for 50 utensils and hygiene products made of biodegradable resins. Our results revealed that one Polylactide (PLA) baby tableware contained 20 mg/L in consumption of potassium permanganate, exceeding the standard of 10 mg/L or less. In all other samples, formaldehyde, lead (Pb), and arsenic (As) levels could be considered very safe and remained below the standard. Moreover, we tested the PLA baby tablewares (n = 21) for migration into a food simulant (4% v/v acetic acid) upon repeated elution at 100℃ for 30 min or UV irradiation for 2 h. We detected increased formaldehyde and As amounts at the repeated 100℃ treatment for 30 min compared to those upon repeated UV irradiation. However, the migration level was markedly low under both conditions. Furthermore, the Estimated Daily Intake (EDI) calculated on an infant-to-child basis from the formaldehyde and As migration at 100℃ for 30 min in the PLA sample was at the maximum value, i.e., 6.0×10^-4 mg/kg b.w./day and 1.3×10^-1 ㎍/kg b.w./day, corresponding to 0.40% and 10.42% of the Tolerable Daily Intake (TDI, 0.15 mg/kg b.w./day) and Provisional Tolerable Weekly Intake (PTWI, 9.0 ㎍/kg b.w./week), respectively. Therefore, in this study, we confirmed that biodegradable synthetic resins are safe to use for food.