• Food Science and Preservation
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• v.10 no.4
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• pp.459-465
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• 2003

This study was carried out to investigate the changes in internal pressure according to various freezing methods, as basic research to protect the destruction of tissues when fruits and vegetables are frozen. The rate of weight loss, caused by the freezing of fruits and vegetables, was found to be the least (0.44∼1.38％) when the immersion freezing method was applied. The difference in the rate of weight loss was the highest when freezing methods were applied to watermelon, and the freezing rate of watermelon whose moisture contents were greater have relatively greater influence on the weight loss. The difference in internal pressures was the least and caused by the volume increase and decrease, when pear, apple, and melon were frozen using the immersion freezing method, while the diffeyence the greatest when the air-blast freezing method was used. As the freezing rate was greater, the internal pressure was less. However, the internal pressure of strawberry and watermelon was the greatest when the immersion freezing method was applied. Frozen without using the thermal equalizing method, the change in internal pressure of fruits was about 2 psig. In contrast, the internal pressure of watermelon applied with the thermal equalizing method was changed in a way similar to that of watermelon not applied with the method, but the former generated a certain level of internal pressure and maintained a significantly low level of internal pressure (about 1.3 psig). When thawed, the internal pressure of samples to which the thermal equalizing method was applied was less than that of what the thermal equalizing method was not applied to. In comparison with the application of multi-step thermal equalizing method, 3∼4 times of application of the thermal equalizing method to the freezing resulted in the decrease of fluctuation range of internal pressure.

• Analytical Science and Technology
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• v.26 no.3
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• pp.174-181
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• 2013

Pyrifluquinazon is classified with a quinazoline insecticide that regulates food intake by controling the feeding behavior acting on the endocrine or nervous system of pests such as aphids and white fly. To keep safety on pyrifluquinazon residues in agricultural commodities a simple, accurate and rapid analytical method was developed and validated using high performance liquid chromatograph (HPLC-UVD). The pyrifluquinazon residues acidified with 1% formic acid in samples were extracted with acetonitrile and partitioned with hexane subsequently to dichloromethane then purified with silica solid phase extraction (SPE) cartridge. The purified samples were detected using HPLC-UVD. The method was validated using apple and pear spiked with pyrifluquinazon at 0.02, 0.05 and 0.1 mg/kg and hulled rice, pepper, soybean at 0.05 and 0.1 mg/kg. Average recoveries were 70.5~107.9% with relative standard deviation less than 10%. The result of recoveries and overall coefficient of variation of a laboratory results in Gwangju regional FDA and Daejeon regional FDA was followed with Codex guideline (CODEX CAC/GL 40). This method is appropriated at pyrifluquinazon residues determination and will be used as official method of analysis.

• Journal of Life Science
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• v.20 no.3
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• pp.424-429
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• 2010

Prunus mume is rich in organic acid, and excels in antioxidant activity. However, development of processed foods using Prunus mume is very limited, and characteristics of its products are different according to the region they are processed in. In this study, we collected 13 kinds of sugar-preserved Prunus mume home-made products in Hadong, and investigated their physical and manufacturing characteristics to select a superior product. 5 kinds of sugar-preserved Prunus mume products were selected according to results of sensory evaluation, and the overall acceptability of product No.13 was superior. Moisture contents of the 5 samples ranged from 45.2~53.3%, and pH and acidity showed similar values at about 2.8 and 0.4%, respectively. Sugar content of product No.13 were slightly lower than other products. Crude protein and lipid contents were similar at about 0.4 and 0.5%, respectively. Hardness value of product No.13, selected by its texture in sensory evaluation, was higher than others. The main components of organic acids were oxalic, malic, citric and fumaric acid, and citric acid content occupied more than 60% of total organic acid content. Also, the main components of free sugar were glucose and fructose.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.577-586
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• 2013

This study investigated black garlic and mugwort extracts have anti-stress activity. The antioxidant activities of extracts from black garlic (BEP), mugwort (MEP), and three mixtures (MPA, 95:5; MPB, 90:10; MPC, 85:15, w/w% for BEP and MEP, respectively) were tested in vitro. DPPH and ABTS radical scavenging activities for the mixtures (MPA, MPB and MPC) were significantly elevated in a dose-dependent manner by the amount of mugwort extract. A restraint stress was imposed on six groups of Sprague-Dawley rats supplemented with an AIN-93 diet (RSC) or one of five kinds of hot water extract drinks containing (black garlic, RS1; mugwort, RS2; and mixtures of black garlic : mugwort at 95:5, RS3; 90:10, RS4, and a mixture of black garlic : mugwort : apple extract : xylitol=90.25:4.75:2:3, RS5; v/v%) for 4 weeks. The normal group was fed with the AIN-93 diet and not exposed to restraint stress. Food intake was higher in the group fed with garlic extract (RS1), while the body weight gain and food efficiency ratio did not significantly change. The total serum cholesterol content in the RS1 and RS2 groups was significantly lower than the RSC group (control), and the RS5 group was not significantly different compared to the RS3 group. The serum triglyceride content was significantly higher RS3~RS5 groups than RS1 and RS2 groups. In terms of HDL-C and LDL-C contents, AI and CRF in the serum were not significantly different between RS3 and RS5 groups. AST and ALP activities of RS1~RS5 groups were significantly lower than the RSC group. The liver total lipid and cholesterol contents of RS1~RS5 groups were significantly lower than RSC group, and triglyceride content was significantly lower in the RS1 group. Glycogen in the liver tissue was significantly higher in the RS2 and RS3 group compared to the RSC group. These results show that the intake of a mixture of black garlic and mugwort extracts may be effective in the alleviation of hyperlipidemia caused by restraint stress.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.30-40
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• 2000

Purpose: During the first year of life, cow's milk protein is the major offender causing food allergy. Cow's milk allergy (CMA) affects 2~7% of infants, of which approximately one-half show predominantly gastrointestinal symptoms. We studied the clinical types of cow's milk allergy with predominantly gastrointestinal symptoms (CMA-GI) of childhood. Methods: The retrospective study was performed on 30 (male 22, female 8) patients who had diagnosed as CMA-GI during 2 years and 3 months from March 1995 to June 1997. Results: 1) Children with CMA-GI presented in the three types of clinical manifestation on the basis of time to reaction to milk ingestion: Quick (Q) onset (5 cases), Slow (S) onset (20 cases), Quick & Slow (Q&S) (5 cases). 2) Age on admission of the three groups was significantly different (p<0.05): (Q onset: $81.4{\pm}67.1$ days, S onset: $31.9{\pm}12.7$ days, Q&S: $366.0{\pm}65.0$ days). Although the body weight at birth was 10~95 percentile in all patients, body weight on admission was different: (Q onset: 10~50 percentile, S onset: below 10 percentile, Q&S: 10~25 percentile). S onset group was significantly different compared with other groups (p<0.05) and 90% of this one was failure to thrive below 3 percentile. 3) Peripheral leukocyte counts were as followings: (Q onset: $5,700{\sim}12,300/mm^3$, S onset: $10,000{\sim}33,400/mm^3$, Q&S: $5,200{\sim}14,900/mm^3$). Slow onset group was significantly different compared with other groups (p<0.05). Serum albumin levels on admission were as followings: (Q onset: $4.2{\pm}0.4\;g/dl$, S onset: $3.0{\pm}0.3\;g/dl$, Q&S: $4.0{\pm}0.3\;g/dl$). S onset group was significantly different compared with other groups (p<0.05) and 85% of this one was below 3.5 g/dl. 4) Although morphometrical analysis on small intestinal mucosa did not show enteropathy in Q onset and Q&S groups, all cases of S onset revealed enteropathy: 45% of this one showed subtotal villous atrophy, 55 % showed partial villous atrophy. 5) Allergic reaction test to other foods was not performed in S onset group because of ethical problem and high risk in general condition. In Q onset group, allergic reaction to one or two other foods: soy formula, weaning formula and eggs. Q&S goup revealed allergic reactions to several foods or to most of all foods except protein hydrolysate formula: eggs, potatos, some kinds of sea food, apples, carrots, beef and chicken. 6) Serum IgE level, peripheral eosinophil counts, milk RAST, soy RAST, skin test were not significantly different among groups. Conclusion: CMA-GI may present in three clinical ways on the basis of time to reaction to milk ingestion, typical clinical findings and morphologic changes in the small bowel mucosal biopsy specimens. This clinical subdivision might be helpful in diagnostic and therapeutic approaches in CMA-GI. Early suspicion is mandatory especially in S onset type because of high risks with malnutrition and enteropathy.