• Food Science and Preservation
• /
• v.14 no.2
• /
• pp.124-130
• /
• 2007

Lettuce (Lactuca Sativa L.) is the most popular salad vegetable crop The purpose of this study was to analyze the quality of lettuce, and residual pesticides in this vegetable, during growth after transplanting. The eatable weight was 40% of the total weight at the commencement of transplanting, but had doubted at harvest after transplanting. As lettuce grew after transplanting, the pH, the sugar level, and the moisture content increased slightly, and the color tended towards yellow rather than greenThe SPDA chlorophyll measurement was 16.84 at 42 day post-ransplantation, and increased to 26.44 at 67 day after transplanting. The contents of vitamin C were 2.5mg/100g wet weight at 60 d after transplantation, but decreased to 2.2mg/100g wet weight 67 day post-transplantation. Mineral (Ca, Fe, K, Mg, and Na) levels rose after transplantation, and attained their highest levels 60 day post-transplantation. The lettuce crop was analyzed for residues of each of 48 pesticides nt 54 after transplantation, and the only such chemical detected was chlorthalonil(0.03 0.25mg/kg wet weight).

• Journal of Food Hygiene and Safety
• /
• v.38 no.3
• /
• pp.140-151
• /
• 2023

This study investigated pesticide residues in 367 agricultural products from local food markets in Ulsan. Pesticide residues in these samples were analyzed using multi class pesticide multi-residue methods on the Korean Food Code for 350 pesticides using GC-MS/MS and LC-MS/MS. Residual pesticides were detected in 79 (21.5%) samples and exceeded maximum residual limits (MRLs) in 4 (1.1%) samples (chwinamul, narrow-head ragwort, green onion, apricot). The range of the hazard index (%) was 0.0000-63.1043%, and values for the pesticides that violated the MRLs were 63.1043 (green onion), 0.5417 (chwinamul), 0.0684 (apricot), and 0.0100 (narrow-head ragwort). This risk assessment study showed that the values of hazard index (%) were less than 100%, indicating that the consumption of these local agricultural food products was not harmful for human health.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
• /
• 2006.05a
• /
• pp.325-328
• /
• 2006

In low nitrite level, treatment of combined with pressure and thermal processing improved cured meat colour comparing with that of only thermal processing. However, visual colour of only pressurised treatment could not be improved at low nitrite level. Pressure treatment could develop cured meat colour when high nitrite level was added. Moreover, pressurisation combined with thermal processing decreased nitrite residuals compared to thermal processing. Therefore the results indicated that pressurisation combined with thermal processing had potential benefits in appearance of cured meat products, promising improved food safety.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.6
• /
• pp.577-583
• /
• 2011

In 2007, pet food contaminated with melamine caused hundreds of dogs and cats to develop renal failure all over the world. In 2008, over 294,000 infants consumed infant formula and developed kidney stones in China. Further investigation revealed that fish feed also contained melamine; this raised concerns about melamine residues in edible fish tissues, which could have caused the urinary tract stone epidemic. In Korea, catfish fed with assorted feed that included cuttlefish organs that contained melamine developed whitening syndrome and fell dead in some populations in 2008. This event raised suspicions about the toxicity of melamine and all feeds containing melamine were immediately recalled. In this study, we investigated the rates of melamine accumulation and depletion in muscle and viscera of catfish to propose proper withdrawal periods. One group of catfish was fed a commercially available diet that contained 30, 100 and 300 mg melamine per kg diet for 14 days. To investigate residual melamine contents in muscle and viscera, other experimental groups were fed a melamine free diet after being fed melamine for 7 days. The residual amount of melamine was analyzed by LC-MS/MS. The melamine concentration in muscle was estimated to be 3.7 mg/kg after 6 days of feeding with a diet containing 300 mg melamine/kg. After 2 days of culture with a melamine free diet, the residual melamine was depleted and the concentration had decreased from 1.15 mg/kg to 0.19 mg/kg in the muscle of catfish fed a diet containing 300 mg melamine/kg for 7 days. The residual amount of melamine was reduced to 0.03 mg/kg in muscle after 7 days of culture with a melamine free diet and was undetectable after a prolonged culture period of 14 days. Catfish tend to excrete melamine rapidly after oral administration and changes in body color were not observed during the short dosing period.

• Korean Journal of Food Science and Technology
• /
• v.53 no.6
• /
• pp.792-798
• /
• 2021

This study was conducted to determine the washing conditions in which surfactants were not detected after washing fruits and vegetables with detergent. Residual surfactants were analyzed using LC-MS/MS. The analyzed surfactants were LAS, SLES, AOS, SLS, CAPB, and LDAO. The survey found that 14% of the respondents used detergent correctly according to the directions indicated. After soaking the samples with 0.2% detergent, the average residual surfactant content was 2.61%. Soaking under 1% and 5% of the detergent, 4.68-5.50% of surfactant remained in the sample. In cherry tomatoes, the surfactants were below the LOD after rinsing twice. However, lettuce was rinsed three times. These results suggest that when using detergent for washing fruits and vegetables, following the labelled usage and rinsing at least three times in 30 seconds could minimize residual surfactants.

• Journal of Acupuncture Research
• /
• v.34 no.3
• /
• pp.39-48
• /
• 2017

Objectives : The objective of this study was to evaluate the effect of Dokhwaljihwang-tang (DJT) intravenous pharmacopuncture on cisplatin-induced emesis and gastric mobility disorder in Wistar rats. Methods : Thirty rats were randomly divided into six groups and cisplatin was administered to all groups except the normal group. The cisplatin group (n=5) received a cisplatin injection only. The saline group (n=5) was injected with cisplatin followed by 0.4 mL of saline. Groups DJT-1, DJT-2, and DJT-3 were injected with cisplatin, followed by 0.315 g/kg, 0.104 g/kg, and 0.034 g/kg of DJT, respectively. Body weight, food intake, and kaolin intake of rats were measured 12 h, 24 h, and 36 h after cisplatin injection. Residual food in the stomach was measured 48 h after cisplatin injection. Results : There was no significant difference in weight. The food intake was not significantly different 12 h after cisplatin administration. All groups except the normal group showed significantly decreased food intake after 24 h. After 36 h, food intake was not significantly different between groups DJT-1, DJT-2, and DJT-3 and the normal group. The kaolin intake of groups DJT-1 and DJT-2 was significantly decreased at 12 h and 24 h after cisplatin injection. Kaolin intake and residual food in the stomach were significantly decreased in groups DJT-1, DJT-2, and DJT-3. Conclusion : In a Wistar rat model, DJT intravenous pharmacopuncture is suggested to be effective for cisplatin-induced emesis and gastric motility disorder. In the future, it is necessary to study the mechanism and chemical composition of each individual constitutive drug.

• Food Science of Animal Resources
• /
• v.38 no.2
• /
• pp.417-430
• /
• 2018

This study was conducted to determine the effects of NaCl concentration and cooking temperature on the color and pigment characteristics of presalted ground chicken breasts. Four treatments with different salt concentrations (0%, 1%, 2%, and 3%) were prepared and stored for 7 d prior to cooking. Each sample was cooked to four endpoint temperatures ($70^{\circ}C$, $75^{\circ}C$, $80^{\circ}C$, and $85^{\circ}C$). The salt concentration affected the color and pigment properties of the cooked ground chicken breasts. As the salt concentration increased, the cooking yield and residual nitrite content also increased. However, the samples with 1%, 2%, and 3% NaCl showed similar nitrosyl hemochrome and total pigment contents. Among the products containing salt, the samples with 3% NaCl showed the lowest percentage myoglobin denaturation (PMD) and the lowest CIE $a^*$ values. The cooking temperature had limited effects on the pigment properties of cooked ground chicken breasts. The oxidation-reduction potential and residual nitrite contents increased with cooking temperature, while the PMD, nitrosyl hemochrome, total pigment contents and CIE $a^*$ values were similar in the samples cooked at different temperatures. These results indicated that the addition of up to 2% salt to ground chicken breasts and storage for 7 d could cause the pink color defect of cooked products. However, the addition of 3% NaCl could reduce the redness of the cooked products.

• Korean Journal of Food Science and Technology
• /
• v.34 no.1
• /
• pp.30-36
• /
• 2002

To use overproduction muskmelon effectively, muskmelon vinegar was prepared by two stage fermentations of alcohol and acetic acid. In the alcohol fermentation using muskmelon, alcohol content showed maximum value (7.47%) in $17.83^{\circ}Brix$ of initial sugar concentration and 82.65 h of fermentation time. Acetic acid content in alcohol fermentation revealed minimum value (0.46%) in $12.17^{\circ}Brix$ of initial sugar concentration and 60.56 h of fermentation time. The fermentation conditions for minimum residual sugar were $10.02^{\circ}Brix$ of initial sugar concentration and 105.61 h of fermentation time. The optimum conditions predicted for each corresponding physical properties of acetic acid fermentation were 200 rpm (agitation rate), 250 h (fermentation time) in acetic content and 200 rpm, 150 h in residual alcohol content.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.8 no.4
• /
• pp.147-152
• /
• 2000

For the probiotic feed production from residual food waste by using the yeast Kluyveromyces marxianus, aerobic liquid fermentation was attempted at $35^{\circ}C$. After grinding finely, optimal fermentation conditions of the substrate was investigated in shaking incubator. By controlling water content yeast growth was studied at each different solid content of 5, 10 and 15% respectively. The most active growth of the yeast was shown at 10%. For the stimulation of the cell growth, mixed culture with Aspersillus oryzae was conducted in a 2 litre-jar fermenter. As the results, the yeast growth rate was increased, but the maximum viable cell count amounted was slightly higher as $3.5{\times}10^9/ml$ than single culture.

• Analytical Science and Technology
• /
• v.23 no.4
• /
• pp.395-404
• /
• 2010

A multi-residual method using gas chromatography coupled with mass spectrometry (GC/MS/ MS) was developed for the analysis of 105 pesticides. This method was tested on lemons, beans and other vegetables. The pretreatment of these pesticides was performed by liquid-liquid partition followed by cleanup with solid phase extraction cartridge (SPE Florisil), after acetonitrile extraction from matrices and sodium chloride (15 g) addition. The recovery ranged from 71.1% to 126.0% except for azinphosmethyl, famoxadone, fenamidone, flufenoxuron and triadimefon in lemons and from 72.5% to 124.5% in bean. In lemon, the limit of detection (LOD) and limit of quantification (LOQ) were 0.001~150 ng/ mL and 0.004~500 ng/mL, respectively.