• Journal of Food Hygiene and Safety
• /
• v.38 no.5
• /
• pp.347-355
• /
• 2023

In this study, polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) were compared in terms of their ability to detect shiga-toxin-producing Escherichia coli (STEC). Various foods were artificially inoculated with STEC to evaluate the limit of detection (LOD), limit of quantification (LOQ), sensitivity, specificity, and efficiency of PCR and LAMP. The LODs were ≤10⁴ and ≤10³ CFU/mL for PCR and LAMP, respectively. The LOQs did not differ between PCR and LAMP. However, of the four considered food types, the sensitivities differed by a maximum of 11.1% for seasoned meat and by a minimum of 8.1% for ground beef. LAMP had higher sensitivity than that of PCR and 100% specificity for all four food types. Therefore, LAMP is a reliable molecular method for detecting STEC as comparable to PCR assay, and its specificity and sensitivity are superior to those of PCR, depending on the food type.

• Journal of Life Science
• /
• v.15 no.5 s.72
• /
• pp.840-846
• /
• 2005

This study was carried out to investigate the effect of electron beam irradiation and cooking temperature on physico-chemical characteristics and lipid oxidation of beef. A total of six beef carcasses ($280\∼300 kg$) that were quality grade $1^{+}$(marbling score No.7, meat color No.4, maturity No.1, texture No.1) was purchased at the commercial slaughter house. The carcasses were transported and washed using high pressure water, and pasteulized with $ 50\% $ ethyl alcohol in the laboratory. After the carcasses were deboned and trimmed, loin and round were taken out to make steak (1.5cm thickness) or ground beef respectively. Samples were wrap or vacuum packaged and irradiated with 0, 3, 4.5, 6 and 7.5 kGy using electron-beam accelerator at Samsung Heavy Industries Ltd. Co. (in Taejun). Irradiated samples were cooked with different methods(electronic pan and gas oven) and temperatures ($ 60^{\circ}C, 70^{\circ}C and 80^{\circ}C$) and used to measure fatty acid composition, TBARS, cholesterol oxide products and panel test scores. The content of saturated fatty acids increased by increasing heating temperature in oven boiling steak (OBS) and pan boiling steak (PBS), and there was no difference by electron-beam irradiation. Both irradiated and non-irradiated treatment were high as the heating temperature increased in TBARS by heating temperature in PBS (p < 0.05) and the amount of Malonaldehyde (MA), standard of fat deterioration, was increased in OBS (p < 0.05). Non-irradiated and 3, 6 kGy treatment produced about 2 fold amount of MA at $ 60^{\circ}C $ compared with $ 80^{\circ}C $. In comparison with PBS, OBS produced much amount of MA and a bit different from non-irradiated treatment but did not show no tendency. As irradiation levels and heating temperature increased, the amount of cholesterol oxides products was increased and also pan-heating method, direct heating method, significantly increased the degree of oxidation compared with oven-heating method, indirect heating method (p < 0.05).

• Journal of Animal Science and Technology
• /
• v.49 no.1
• /
• pp.41-50
• /
• 2007

Data from a comparative slaughter experiment with two hundreds of Korean native (Hanwoo) beef steers were utilized to determine net energy and protein requirements for growth (NEg and NPg). Eight randomly selected steers were used in the initial slaughter group of 6 month of age and the remaining steers allocated to treatments within two groups. The restricted groups were fed 1.2 to 1.5% concentrate per kg body weight (BW) in the growing period (6～12 month of age), 1.7 to 1.8% concentrate per kg BW in the early fattening period (13～18 month of age), and concentrate feed ad libitum in the late fattening period (19～30 month of age). Ad libitum groups were fed concentrate ad libitum through the whole period. Rice straw was offered ad libitum for 24 month of two feeding systems. The steers were slaughtered when animals reached every 2 month from 8 to 30 month of age. For all body composition determinations, whole empty body components were weighed, taken each proportional subsample was ground for chemical analysis. Equations developed with the pooled data to predicted NEg and NPg were similar to the equations of Japanese Feeding Standard for Beef Cattle (2000). First equations were developed to predicted NEg; NEg = 0.05332×LBW0.75×DG for restricted treatment and NEg = 0.04912×LBW0.75×DG for ad libitum treatment. Second equations were developed to predicted NPg; NPg = DG × (224.7－0.251×LBW) for restricted treatment and NPg=DG×(210.1－0.214×LBW) for ad libitum treatment.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.1612-1612
• /
• 2001

The production of grain for export and domestic use is one of Australia's most important agricultural industries, and the NIR technique has been used extensively over many years for the routine monitoring of grain quality, particularly moisture and protein content. Because most Australian grain is intended for human food production, the determinants of grain quality for livestock feed, apart from protein, have been largely ignored. However the increasing use of grain for feeding to pigs, poultry, beef cattle and dairy cows has led to an important national research project entitled “Premium Grains for Livestock”. Two of the objectives of this project are to determine the compositional and functional characteristics of grains which influence their nutritional quality for the various classes of livestock, and to adopt rapid and objective analytical tests for these quality criteria. NIR has been used in this project firstly to identify a set of grain samples from a large population of breeders' lines which showed a wide spectral variation, and hence a potentially wide variation in nutritional value. The selected samples were not only subjected to an extensive array of chemical, physical and in vitro analyses, but also were grown out to produce sufficient quantities of grain to feed to animals in vivo studies. Additional grains were also strategically selected from farms in order to include the effect of weather damage, such as rain, drought and frost. In this study to date, NIR calibrations have been derived or attempted, on both ground and whole grains, for in vivo dry matter digestibility (DMD), pepsin-cellulase dry matter disappearance, protein, fat, acid detergent fibre, neutral detergent fibre, starch, in sacco DMD and in vitro assays to simulate starch digestion in the lumen and small intestine. Results so far indicate high calibration accuracy for chemical components (SECV 0.3 to 2.6%) and very promising statistics for in vivo DMD (SECV 1.8, $R^2$ 0.93, SD 7.0, range 61.9 to 92.3, n=60). There appears to be some potential for NIR to estimate some in vitro properties, depending upon the accuracy of reference methods and appropriate sample populations. Current work is in progress to extend the range of grains with in vivo DMD values (a very laborious and expensive process) and to increase the robustness of the various NIR calibrations, with the aim of implementing uniform testing procedures for nutritional value of grains throughout Australia.

• Journal of Animal Science and Technology
• /
• v.48 no.4
• /
• pp.533-540
• /
• 2006

This experiment was conducted to determine crude protein requirements for maintenance (CPm) of growing Hanwoo steers. Eighteen Hanwoo steers (173.7kg) were allocated randomly to diets with three levels of crude protein in the concentrate by replacing ground corn with corn gluten meal: 0% (LCP), 7.2% (MCP) and 14.2% (HCP), respectively. Hanwoo steers in each treatment were fed diets containing rice straw (20%) and concentrates (80%). CP intake was 5.5, 7.8 and 10.7g/BW0.75 for LCP, MCP and HCP, respectively. Protein balance was －0.05, 2.36 and 4.07g/BW0.75 for LCP, MCP and HCP, respectively. Intercept of the regression equation between CP intake and retained CP indicated that CPm was 5.56g/BW0.75. The estimate of CPm adopted by Korean Feeding Standard (2002) was almost 20% higher than that adopted by Japanese Feeding Standard for Beef Cattle (2000); this would need to be verified with more feeding trial data set including protein requirements for growth.

• Journal of Fisheries and Marine Sciences Education
• /
• v.18 no.2
• /
• pp.164-171
• /
• 2006

kochukaru (chili powder) and various vegetables. As its main ingredient, fresh or sea-water fish is cut into several pieces and boiled with ground beef and green vegetables such as watercress as well as garland chrysanthemum. In addition, onion, radish, chilies, crown daisy, garlic and some times, pumpkin and bean curds are added to the mixture to absorb the kochujang which is the base flavor of this dish. It is then seasoned with kochukaru, garlic, soy sauce and if needed, more kochujang to suit everyone's taste buds. Restaurants that offer this dish often allow you to select your fish from a tank. Many specialty seafood restaurants have several tanks from which you may choose a fish. Popular fish for this dish may include Korean rockfish, flounder, yellow corvina, codfish, croakers, pollacks, and even fresh water fish like carp and trout. In addition, other shell fish such as crabs, clams and oysters can be also added to this soup to compliment and enhance its spicy but refreshing flavor. This soup is one of Korean's most popular dishes while drinking soju. If you order sushi or sashimi, the soup is made from the left-over parts of the fish. The objective of this study is to determine a standardized recipe of Maeun-Tang and to investigate consumption so as to increase its intake opportunities for consumers through its development. Fish species used in Maeuen-Tang's recipes were flounder, Korean rockfish and other fish. Onion, radish, chilies, crown daisy, garlic and some times, pumpkin and bean curds were added to the mixture to absorb the kochujang which is the base flavor of this dish. Most of the stock used in Maeuen-Tang's recipes is pure water, fish stock and vegetable stock, 1.0-1.5 Korean rock fishes and 0.5-1.0 flounders, with its head and bone, which were used in 3-4 portions of Maeun-Tang. Most of the seafood restaurants used seasoning which didn't age and was made by the restaurant. The cooking equipment used in the Maeuen-Tang's recipes were a cook-port and earthen bowl.

• Food Science of Animal Resources
• /
• v.25 no.2
• /
• pp.149-155
• /
• 2005

This study was conducted to investigate effects of cooking method on physicochemical characteristics and qualities of hamburger patties processed with ground pork/beef meat $(20\%\;fat)$. Hamburger patties were cooked by electric griddling, fan frying, microwave, conventional cooking, and charbroiling. Cooking rates were affected by cooking methods, had the highest in patties cooked in microwave oven. Hamburger patties by microwaving were also higher moisture content, but were lower protein and fat content compared to other methods. Electric griddling and microwaving were higher cooking yield, lower diameter changes in patties than other methods, but pan frying showed the opposite effects. Higher values of hardness and brittleness in pan frying than those of other methods were showed, but pan frying had the highest overall acceptability in sensory evaluations.

• Korean Journal of Food Science and Technology
• /
• v.34 no.2
• /
• pp.274-282
• /
• 2002

The ethanol extract and n-hexane fraction from Hypericum ascyron L. showed strong growth inhibition at 25 ppm on 5 strains of Listeria monocytogenes for 72 hr at $32^{\circ}C$. The purified substance, H2-5-2 fraction, was isolated by silica gel column and preparative thin layer chromatography from n-hexane fraction of Hypericum ascyron L. The H2-5-2 fraction showed a strong bacteriostatic activity on 5 strains of L. monocytogenes at 10 ppm in tryptic soy broth, and the viable cell was reduced 1 log cycle compared to initial cell number. The n-hexane fraction of Hypericum ascyron L. showed strong growth inhibition at 25 ppm on Bacillus cereus and Staphylococcus aureus, and at 50 ppm on Vibrio parahaemolyticus for 72 hr. The purified antimicrobial substance, the H2-5-2 fraction, was assumed as high unsaturated sterol by $^1H-NMR$ and $^{13}C-NMR$. On application test using minced Alaska pollack and ground beef, the n-hexane fraction of Hypericum ascyron L. at the level of 250 ppm was applied at $32^{\circ}C$ and $5^{\circ}C$. At $32^{\circ}C$ storage condition, the antimicrobial substances did not reduced L. monocytogenes ATCC 19113, meanwhile at $5^{\circ}C$ storage condition, L. monocytogenes ATCC 19113 was reduced in viable number.

• Korean journal of food and cookery science
• /
• v.32 no.4
• /
• pp.476-491
• /
• 2016

Purpose: This study investigated consumers' perception of food safety and risk from foodborne illness and consumption pattern of meat and processed meat products in Korea. Methods: A quantitative survey was performed by trained interviewers, surveying 1,500 adults who were randomly selected from six major provinces in Korea. Results: Most of the respondents reported foodborne illness risk related to the consumption of raw meat but not related to heated meat and processed meat products. As respondents perceived the risk of food poisoning from raw meat, the purchase and intake decreased (p<0.001). Most of the respondents considered a low possibility of foodborne illness at home. Seventy-seven percent of the respondents thought that bacteria and virus are the main causes of foodborne illness. Improper storage practice (40.7%) and unsafe food material (29.3%) were the main risk factors contributing to foodborne illness. Perception and practice of food safety was significantly different by the residency area. The most preferred meat, processed meat, and processed ground meat products were pork (58%), ham (31.1%), and pork cutlet (40.4%), respectively. The most preferred cooking method was roasting, regardless of the type of meat, but the second preference for cooking method was significantly affected by the type of meat (p<0.001): stir-fried pork, beef with seasoning, fried-chicken and boiled duck. Frequency of eating out was 0.75/day on weekdays and 0.78/day on weekends at the mainly Korean BBQ restaurant. Conclusion: The results of this study could be used to develop science-based education materials for consumer and the specific guideline of risk management of meat and processed meat products.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.6
• /
• pp.1003-1008
• /
• 2000

Antioxidative activities (AA) of mustard leaf kimchi (MLK) by the addition of optional ingredients among selected minor materials were studied. In order to determine AA of MLK with different spices, the model systems of ground cooked beef with green onion, garlic, and red pepper powder were prepared and stored for 4 weeks at 4$^{\circ}C$. AA of red pepper added group was stronger than those of others. AA of red MLK was relatively higher than that of (green) MLK. For the enhancement of AA of MLK, another model systems were prepared with the selected antioxidative optional ingredients, which were bonnet bellflower root, leek, burdock, sea tangle, sea mustard, seastaghorn at the level of 2% or 4%. The extracts of water, 75% methanol and hexane of MLK, bonnet bellflower root added MLK, and seastaghorn added MLK had a considerable AA with the inhibition of peroxide formation during the autioxidation of linoleic acid mixtures in aqueous model systems at 37$^{\circ}C$. Therefore, AA was more effective in MLK containing specific optional ingredients than that of MLK alone significantly.