• Journal of Food Hygiene and Safety
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• v.8 no.3
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• pp.147-150
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• 1993

A novel rapid and sensitive method to detennine residual oxolinic acid in Acetes japonicus was developed. The residual oxolinic acid was extracted with ethylacetate and diluted oxalic acid, and interfering substances were removed by hexane. Fifty ppb residual concentration in the extract could be quantitated by UV-HPLC and the recovery rates were 79-91% according to the fortified amounts.

• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.287-290
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• 1996

To control the maximum residue level (MRL) for sulfamethazine (SMZ) residues in pork tissue, a microbial inhibition method is a regulatory screening assay method in Korea. Microwell plate-based competitive enzyme immunoassay (ELISA) kit is avalable for routine screening of SMZ residues in pork tissue. One ELISA kit is evaluated. Phosphate buffer extracts of samples fortified with SMZ at 0, 1, 5, and 10 ng/g were used in a recovery test of the kit. Market pork samples were assayed by the kit. Recovery of sulfamethazine was 104% at 10 ng/g. Intraassay variations and interassay variations for the kit were 7.70% and 5.76%, respectively. Concentration causing 50% inhibition of color development compared with blanks was 16.4ng. The violative pork samples with over MRL (0.1 $\mu\textrm{g}$/g) was 4 of 32 cases (12.5%) by used ELISA kit. This result indicates a possibility of the ELISA kit for screening test of SMZ residues in pork tissue, and still needs a comfirmatory assay for mandatory purposes.

• Journal of Food Hygiene and Safety
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• v.9 no.1
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• pp.37-42
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• 1994

Four sulfoanmides ; sulfamerazine ; sulfamethazine, sulfathiazole and sulfadimethoxine from muscle, kindney, liver and heart tissues of pork and chicken by LC. Residual sulfonamides were extracted with dichloromethane and determined on a Sperisorb ODS-1 column(250mm$\times$4.6mm id) with acetonitrile/water/acetic acid (30/70/0.3 v/v) as a mobile phase at 260nm. Recoveries from 4 tissues of pork and chicken samples fortified with 50 and 100 ppb were 71.2~87.2% and 73.7~89.6%, respectively. The detection limit was 0.03 $\mu\textrm{g}$/g in each drug. Sulfamethazine in 5 samples of pork. And sulfadimethoxine in 5 samples and sulfamethazine in 3 samples were also detected from 41 samples of chicken. The order of residue levels of sulfonamides in tissues was kidney>liver>heart>muscle, respectively. The residue levels of sulfonamides from kidney and liver were 0.03~0.15 $\mu\textrm{g}$/g in porks and 0.03~0.10 $\mu\textrm{g}$/g in chickens.

• Journal of Food Hygiene and Safety
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• v.9 no.2
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• pp.89-94
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• 1994

A simple, safe, and sensitive gas chromatographic method using packed column and electron capture detector to analyze 2, 4-D herbicide in imported lemon, grapefruit, and orange was described and its usefulness evaluated. In this scheme of analysis the acid herbicide was converted into its alkyl esters by an one-step reaction prior to analysis. The herbicide in the fruits was extracted with ethyl acetate and partitioned against dichloromethane for purification, and the extracts finished partitioning were derivatized with alcohol, using sulfuric acid as a catalyst to form the corresponding alkyl derivatives. The analytical scheme studiedwas found to be applicable for the herbicide in the fruits without a column clean-up procedure. The mean recoveries of the herbicide for lemon samples fortified at 0.1 mg/kg and 1.0 mg/kg were 93% and 95%, respectively. The detection limit was 0.5 $\mu\textrm{g}$/kg for 2.4-D methyl ester.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.237-243
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• 2017

To investigate the effects of lactic acid bacteria (LAB), Lactobacillus sakei, Lactobacillus curvatus, and Lactobacillus brevis, commonly found in kimchi, on N-nitrosodimethylamine (NDMA) and its precursors such as nitrite, dimethylamine (DMA), nitrate, and biogenic amines, Baechu (Chinese cabbage) kimchi prepared with and without LAB and $NaNO_2$ was periodically monitored for 20 days to analyze concentrations of NDMA and its precursors. Control was amine and nitrite-rich kimchi. NDMA and its precursors were analyzed to determine differences in concentrations between LAB-fortified kimchi and the control. The amounts of NDMA, nitrite, DMA, and nitrate remaining in LAB-fortified kimchi were significantly reduced compared with those of control kimchi. In addition, biogenic amines were significantly lower in kimchi prepared with L. sakei, L. curvatus, and L. brevis. These results suggest that addition of LAB to the kimchi preparation would be a promising solution for production of NDMA-reduced kimchi.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.468-479
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• 1989

The oxidative stability of the ramyon prepared with rapeseed oil fortified with antioxidants or blended with palm oil was studied to explore the possibility of substituting it for Imported frying fats and oils. Natural tocopherols, butylated hydroxyanisole(BHA), tertiarybutyl hydroquinone(TBHQ), and ascorbyl palmitate with citric acid were used at a level of 0.02 percent. Blended oils were prepared by adding a palm oil to the rapeseed oil at ratios of 7:3, 5:5, and 3:7(w/w), respectively. Ramyon samples were stored at $35.0{\pm}0.5^{\circ}C$. for 90 days. The values of parameters, such as peroxide value, unsaturation ratio, and dielectric constant, of the extracted oils were regularly determined. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samples was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of TBHQ ${\gg}$ ascorbyl palmitate with citric acid>BHA>natural tocopherols. The oxidative stability of the ramyon prepared with the rapeseed oil containing 0.02 percent TBHQ was almost as good as that of the ramyon prepared with the palm oil. The stability of the ramyon prepared with the blended oil containing 70 percent palm oil was also as good as that of the ramyon prepared with the palm oil.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.269-276
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• 1983

Experiments were performed to study the rheological and baking properties of bread fortified with various amounts of filefish protein concentrate (FPC). Doughs were prepared from mixtures containing wheat flour and 5,10,15 and 20% of FPC. Standard methods were used to evaluate the rheology of doughs and characteristics of bread. The results were as follows. 1. The water absorption of the fortified doughs increased as FPC increased. FPC caused an increase in development time and stability as measured by Farinograph. 2. In the extensigraph test, FPC yielded a decrease in extensibility and an increase in resistance to extension. 3. Baking tests demonstrated that addition of FPC decreased the volume of loaf and made the crumb darker and coarser. 4. Additional tests were made to examine effect of sodium stearoyl lactylate (SSL) added at 0.25, 0.50, 1.00 and 2.00% on doughs containing 10% headed & gutted FPC. The most appropriate amount of SSL as an additive was 0.5%. 5. In the farinograph, adding 0.5% SSL could delay dough development time and greatly increase stability. 6. When 0.5% SSL was added on doughs containing 5,10,15 and 20% headed & gutted FPC, baking quality was greatly improved. The breads containing up to 10% were acceptable by the addition of SSL, but not in higher level of FPC. 7. The results of sensory evaluations of bread showed that the color, texture and taste of bread containing 5% whole FPC and 5, 10% headed & gutted FPC were reasonably gacceptable.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.196-202
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• 2009

The effects of the salts fortified with seaweed functional components on blood pressure, serum minerals, and hematochemicals in spontaneously hypertensive rats (SHR/NCrj) and normotensive rats (WKY/NCrj) were investigated. SHR and WKY rats were assigned to four groups, with 8 and 6 rats in each group: laver salt (A), fucoidan+laver high salt (B), fucoidan + laver low salt (C) and refined salt as a control (D). The final blood pressure (BP) of SHR and WKY species in contrast with reference BP were low in groups A and C as compared with control group. In terms of serum mineral content, $Na^+$ levels were similar in SHR and WKY, but $K^+$ levels were higher in the group B in SHR. Serum triglyceride levels were lower in groups A and C, but the levels of HDL- and LDL- cholesterol were significantly higher and lower in group A than those of controls, respectively (p<0.05). These results demonstrated that the salts fortified with laver might suppress blood pressure in rats, and also may improve mineral and lipid metabolism.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.581-587
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• 2003

This study was designed to examine the effect of icroencapsulated iron fortified drink yogurt and vitamin C as a bioavailable helper of iron on chemical and sensory aspects during 20 d storage. Coating material was polyglycerol monostearate (PGMS), and ferric ammonium sulfate and vit C were selected as core materials. The highest efficiency of microencapsulation of iron and vit C were 73% and 95%, respectively, with 5:1:50 ratio (w/w/v) as coating to core material to distilled water. Iron fortification did not affect the fermentation time required for the drink yogurt to reach pH 4.2. The addition of uncapsulated iron decreased the pH during storage. TBA absorbance was significantly lower in capsulated treatments than in uncapsulated treatments during storage. In sensory aspect, the yogurt sample added with uncapsulated iron and vit C, regardless of capsulation, showed a significantly high score of astringency, compared with those of control and other groups. A significantly strong sourness was observed in treatment containing capsulated iron and uncapsulated vitamin C at every time interval. The present study provides evidence that microencapsulation of iron with PGMS is effective for iron fortification in drink yogurt.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.722-727
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• 2007

Mucilage containing ${\gamma}-polyglutamic$ acid (PGA) was efficiently generated by the solid-state fermentation (SSF) of soybean grit by Bacillus firmus NA-1. B. firmus NA-1 was shown to be a glutamate-dependent strain for PGA production. The SSF of soybean grit was optimized in order to produce mucilage with a fortification of 5% glutamate, resulting in higher levels of mucilage production (6.14%) and a higher consistency index ($1.1\;Pa\;sec^n$). The sticky mucilage was comprised of 38% PGA, 7% levan, and some biopolymers. With regard to the viscoelastic properties of the mucilage solution, the viscous modulus (G") obtained from soybean grit fortified with 5% glutamate was approximately 64 times higher titan that of the mucilage solution obtained without glutamate. Although the addition of glutamate in the SSF of soybean grit influenced the rate of PGA production, the molecular weight of PGA remained unaltered, and was detected in a range between 1,400-1,440 kDa.