• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.131-140
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• 2014

The objective of this study was to develop a simultaneous method of 8 penicillin antibiotics including amoxicillin, ampicillin, cloxacillin, dicloxacillin, nafcillin, oxacillin, penicillin G and penicillin V in meat using LC-MS/MS. The procedure involves solid phase extraction with HLB cartridge and subsequent analysis by LC-MS/MS. To optimize MS analytical condition of 8 compounds, each parameter was established by multiple reaction monitoring in positive ion mode. The chromatographic separation was achieved on a $C_{18}$ column with a mobile phase of 0.05% formic acid and 0.05% formic acid in acetonitrile at a flow rate of 0.2 mL/min for 20 min with a gradient elution. The developed method was validated for specificity, linearity, accuracy and precision in beef, pork and chicken. The recoveries were 71.0~106%, and relative standard deviations (RSD) were 4.0~11.2%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.003~0.008 mg/kg and 0.01~0.03 mg/kg, respectively, that are below maximum residue limit (MRL) of the penicillins. This study also performed survey of residual penicillin antibiotics for 193 samples of beef, pork and chicken collected from 9 cities in Korea. Penicillins were not found in all the samples except a sample of pork which contained cloxacillin (concentration of 0.08 mg/kg) below the MRL (0.3 mg/kg).

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.123-130
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• 2014

A simultaneous determination was developed for 9 aminoglycoside antibiotics (amikacin, apramycin, dihydrostreptomycin, gentamicin, hygromycin B, kanamycin, neomycin, spectinomycin, and streptomycin) in meat by liquid chromatography tandem mass spectrometry (LC-MS/MS). Each parameter was established by multiple reaction monitoring in positive ion mode. The developed method was validated for specificity, linearity, accuracy, and precision based on CODEX validation guideline. Linearity was over 0.98 with calibration curves of the mixed standards. Recovery of 9 aminoglycosides ranged on 60.5~114% for beef, 60.1~112% for pork and 63.8~131% for chicken. The limit of detection (LOD) and limit of quantification (LOQ) were 0.001~0.009 mg/kg and 0.006~0.03 mg/kg, respectively in livestock products including beef, pork and chicken. This study also performed survey of residual aminoglycoside antibiotics for 193 samples of beef, pork and chicken collected from 9 cities in Korea. Aminoglycosides were not found in any of the samples.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.617-625
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• 2006

This study was done to provide basic data for the operation of a safer cook-chill system by comparing and evaluating the quality of foods which were prepared using the sous vide cook-chill system and the conventional cook-chill system, according to the preparation methods and storage temperature. Simmered chickens in soy sauce were prepared using the sous vide cook-chill system and the conventional cook-chill system and their quality was evaluated at the time of preparation and storage. Firstly, foods were prepared using the sous vide cook-chill (SVCC) system and the conventional cook-chill (CC) system and the redquired time and temperature during each preparation stage were measured and physicochemical (pH, Aw, and moisture content) and microbial qualities were evaluated. Secondly, in order to evaluate the quality and safety, the moisture content and microbial (standard plate count, coliform count, psychrotrophic bacteria count, and anaerobic bacteria count) qualities were evaluated according to the preparation methods and temperatures after the foods were stored at 3$^{\circ}C$ and 10$^{\circ}C$ for 10 days and reheated.

• The Korean Journal of Food And Nutrition
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• v.28 no.2
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• pp.302-312
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• 2015

This study was conducted to evaluate the effects of constitutional diets in comparison with general low calorie diets in obese women. The subjects were 52 adult obese women that participated in a calorie restriction diet program (control group, n=16) or a constitutional diet program (experimental group, n=36) for 8 weeks. The subjects in the experimental group were classified as negative (Yin) or positive (Yang) constitution. The obesity management program focused on the calorie restriction diet (300~400 kcal reduction per day) for the control group, whereas, for a constitutional diet without calorie restrictions was allowed for the experimental group. Daily intakes of nutrient and food were assessed using a 24 hr recall method. Body measurements and blood biochemical parameters were measured at baseline and after 8 weeks. After the intervention, weight, body fat, BMI, waist circumference and hip circumference decreased significantly in both the control and experimental group. Energy intake increased from 1,679.6 kcal to 1,810.6 kcal along with significant increase in protein, carbohydrate, fiber, calcium, phosphorus, iron, zinc, vitamin A, vitamin $B_1$, vitamin $B_2$, niacin and vitamin C in the experimental group. Calcium intake increased from 54.0% to 72.4% of DRI in the experimental group. Hemoglobin concentrations were significantly decreased in the control group, but were increased in the experimental group. In addition, blood glucose, serum total cholesterol and triglyceride were significantly decreased in the experimental group. In conclusion, consumption of a constitutional diet without calorie restrictions for 8 weeks was effective for weight reduction with improvement of blood glucose, serum cholesterol and triglyceride.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.463-468
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• 2007

This study was conducted to investigate the effect of maturity scores [2 (bull), 2 (steer), 3-9 (cow)] and the number of extractions (up to 4 times) on the chemical properties of water extract from Hanwoo shank bones (arm, fore shank, round and hind shank). The turbidity, meat color (CIE L value), collagen, protein, caloric and chondroitin sulfate contents of samples were observed. The turbidity and lightness were higher for water extract of Hanwoo shank bones with a maturity score of 2 (bull and steer) than maturity scores of 3-9 (cow) (p<0.05). The turbidity and lightness of water extract from shank bones of all Hanwoo maturity scores significantly increased with the 1st and 2nd extractions, but significantly decreased with 3rd and 4th extractions (p<0.05). The collagen and protein contents were highest for water extract from Hanwoo shank bones of maturity score 2 (bull and steer) (p<0.05). The caloric and chondroitin sulfate contents were higher for water extract from Hanwoo shank bones of maturity score 2 (bull and steer) than maturity scores of 3-9 (cow) (p<0.05). As the number of extractions increased, the chondroitin sulfate content significantly decreased (p<0.05). Based on these results, differences correlating with maturity scores were found only with collagen and protein contents. Therefore, further studies should be considered to address whether different maturity scores affect the price of shank bones in the meat industry.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.475-481
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• 2007

A total of 40 Korean native pigs (gilt 21, boar 19) were used to investigate the meat quality, nutritional and sensory properties by gender. Gilts had significantly lower moisture and ash contents (%) than boars, but protein contents were not significantly different between the gender (p<0.05). Gilts contained high intramuscular fat contents were significantly lower in Warner-Bratzler shear force (WBS) and Water holding capacity (WHC) when compared to those of boars. There was no significant difference in meat color L (lightness) and a (redness) values between the gender (p>0.05), but gilt had higher b (yellowiness) values than boar. Regarding amino acid compositions, there were glutamic acid (3.25%), aspartic acid (1.94%) lysine (1.83%), leucine (1.77%), alanine (1.17%) and arginine (1.15%) for gilts and boars. There were no significant differences in the contents of the minerals such as calcium, potassium, phosphorous, sodium, magnesium, iron, zinc and copper (p>0.05). The results of fatty acid composition showed that gilts had significantly higher C16:1n7, C18:1n9, in intramuscular fat., whereas they had significantly higher contents of C14:0, C16:0, C20:1n9, C20:5n3 in subcutaneous fat than boars (p<0.05). Boars had significantly higher contents of C18:0, C18:1n7, C18:2n6, C20:1n9, C20:4n6, C22:4n6 in intramuscular fat and they had significantly higher contents of C18:2n6, C22:4n6 than gilts in subcutaneous fat (p<0.05). In sensory evaluation, gilts had significantly higher scores in juiciness, tenderness and flavor when compared to boars (p<0.05).

• Food Science of Animal Resources
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• v.29 no.3
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• pp.364-373
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• 2009

This study was conducted to provide fundamental information in developing muscle-specific strategies to improve the quality and value of low-fat pork cuts upon evaluating meat qualitative parameters of twenty one (21) muscle samples selected from ten (10) market-weighted crossbred pigs. The following observations were made. The pH was highest for subscpularis and lowest for gluteus superrificialis (p<0.05); the subscpularis can hold water the most (p<0.05), biceps femoris loses the most content upon cooking, while subscpularis loses the least content (p<0.05); gluteus superrificialis (p<0.05) has the most purge loss contents, and infraspanatus and gastrocneminus contained the most collagen, while adductor had the least collagen (p<0.05); biceps femoris has the most WB-shear force values while subscpularis (p<0.05) has the least; pectoralis profundi-fan was the most protein soluble; semitendinosus has the most gel strength (p<0.05). In the properties of meat color, tensor fasciae latae shows the highest CIE $L^*$ (lightness) values (p<0.05) and supraspinatus, brachiocephalicus and infraspanatus have the highest CIE $a^*$ (redness, p<0.05) values; vastus intermedius has the most myoglobin content while longissimus dorsi (p<0.05) has the least; infraspanatus is the most tender (one of the sensory properties) while biceps femoris was the most tough among all tested muscles (p<0.05); the pectoralis profundi-fan was the most flavorful pork while vastus intermedius was the least (p<0.05); supraspinatus, infraspanatus, semitendinosus, and vastus intermedius were juiciest while longissimus dorsi was the driest (p<0.05). In overall likeness, the semitendinosus and infraspanatus were most liked while biceps femoris and longissimus dorsi were the least (p<0.05). This study presents the results of several parameters in selected pork muscle samples which are useful information for developing new muscle-specific strategies to improve the quality of consuming meat and meat products.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.277-285
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• 2010

The objective of this study was to manufacture spent layer chicken meat products by natural freeze-drying. The spent layers of chickens that were slaughtered at 80 wk were obtained from a local slaughter house and separated into two halves of carcasses. The samples were divided into the following groups: 1) control (non-curing), 2) curing, and 3) curing with 2% trehalose before drying. The cured meats were placed at $2^{\circ}C$ for 7 d and then transferred to a natural drying spot located in Injae City, Gangwondo, Korea. The experiment was conducted from January to March in 2008. The average temperature, RH, and wind speed were $-1.5^{\circ}C$, 63%, and 1.8 m/sec, respectively. The cured treatments showed higher pH, lower Aw and lower shear force value compared with the control. Based on the results of TBARS (2-thiobarbituric acid reactive substances) level and volatile basic nitrogen value, lipid oxidation and protein deterioration were inhibited in curing treatments during drying. Trehalose acted as a humectant because it maintained a lower water activity despite the relatively higher moisture content during drying. The polyunsaturated fatty acids content and sensory attributes were higher in cured treatments than in the control during drying. Most of the bacterial counts in the treated groups were lower by 2 Log CFU/g after 1 mon of drying, and Salmonella spp. and Listeria spp. were not found in any treatment. There was also no microbial safety problem associated with dried meat products. Based on the results of this experiment, dried meat products could be manufactured from precured spent layer chickens by natural freeze-drying during winter.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.619-625
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• 2001

We determined whether the supplementation of Polygonatum Odoratum (Mill) Druce (POD) extract had a good effect on insulin resistance in peripheral tissues of 90% pancreatectomized (Px) and sham-operated (Sham) male Sprague Dawley rats. Px and Sham rats were divided into two groups; one group daily consumed 0.3 g of POD extracts per 1 ㎏ body weight for two months, and the other group had a placebo. All rats freely consumed a 40% fat diet. At the end of the experiment, a euglycemic hyperinsulinemic (EH) clamp was performed in a fasting, awake, and unstressed state to determine insulin resistance. At EH clamp, body weights were higher in Sham rats than Px rats, and serum glucose levels of baseline were affected by diabetic status and POD administration. Serum insulin concentrations were higher in Sham rats than Px rats, and POD administration decreased them in Sham rats compared to P. Glucose disposal rates in peripheral tissues increased with POD in both Px (n=10) and Sham (n=10) rats. But glycogen deposits in soleus muscle increased with POD administration in Px and Sham rats, and total glycogen synthase activity and fraction velocity were higher in POD groups. Triglyceride contents in quadriceps muscles decreased with POD in Px rats. In conclusions, POD improves insulin resistance by enhancing glucose utilization with increasing glycogen deposit and decreasing triglyceride contents in muscles.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.407-412
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• 2002

This study was carried out to investigate the differences in malt quality between high-protein Korean malting barley and low-protein Korean malting barley. The average protein content of each area in the 1996 crops was as follows; The protein content of Doosan-29 from Jeon-Nam was 14.1% (d.b), that of Sacheon-6 from kyung-Nam was 13.4% (d.b) and that of Doosan-8 from Je-Ju was 12.8% (d.b). In the micro malting trial for high and low protein malting barley, the original protein level of the malting barley was not changed and decreased during germination days. The malt friability of high-protein malting barley was very low, but that of low-protein malting barley was high. The malt friability of high-protein malting barley was 44.5% and that of low-protein malting barley was 84.2%. In proportion to an increase of +1% (d.b) in barley protein, the fine grind extract of malt was decreased -0.86% (d.b). Economically, it was the most negative factor for high-protein Korean malting barley. The ${\beta}-glucan$ content of high-protein malting barley was higher than that of low-protein malting barley. Wort viscosity and malt color were increased and Kolbach index was decreased in high-protein malting barley. Free amino nitrogen and diastatic power for high-protein malting barley were higher than those of low-protein malting barley. They were the most positive factors for high-protein Korean malting barley.