• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.519-523
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• 1989

The effects of carbon, nitrogen sources and culture conditions on glucoamylase production from Aspergillus sp. were investigated. Among tested carbon sources, soluble starch was most effective for the production of the enzyme, and the level of concentration for the optimal enzyme production was found to be 5%. For nitrogen sources, yeast extract was best for the enzyme production, with the level of 0.1%. The enzyme was maximally produced by cultivating the organism at medium of initial pH 6.0, and temperature of 28$^{\circ}C$. Wheat bran was most suitable for the enzyme production from the organism in solid state culture.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.359-364
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• 2010

Lactobacillus acidophilus A12 was isolated from chicken feces for use as an immunostimulating livestock probiotic. The purpose of this study was to optimize the production of L. acidophilus A12 using response surface methodology (RSM). Initially, the influence of growth medium was studied in terms of carbon sources (glucose, fructose, lactose, glycerol, sucrose, ethanol, and mannitol), nitrogen sources (beef extract, yeast extract, malt extract, and tryptone), and inorganic salts ($CaCl_2$, $MgSO_4$, $KH_2PO_4$, $(NH_4)_2SO_4$, $FeSO_4$, and NaCl). Through one factor-at-a time experiment, lactose, yeast extract, and $CaCl_2$ were determined to be the best sources of carbon, nitrogen, and inorganic salt, respectively. The optimum composition was found to be 17.7 g/L lactose, 18.6 g/L yeast extract, and 0.9 g/L $CaCl_2$. Under these conditions, a maximum cell density of 9.33 Log CFU/mL was produced, similar to the predicted value.

• Journal of Nutrition and Health
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• v.17 no.2
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• pp.85-93
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• 1984

The present studies were designed to compare the effects of dietary fat sources and levels on plasma and tissue cholesterol. Changes in plasma total cholesterol and HDL-cholesterol, cholesterol concentration in aortas, liver and intestines were determined in young rats fed diets providing dietary fat as corn-oil or butter and levels as 10%, 20% or 30% of calories respectively 1) Plasma total cholesterol and HDL-cholesterol levels were little sensitive to the modification of dietary fat sources and levels. 2) Dietary cholesterol increased the levels of plasma total cholesterol and this effect was accentuated by feeding butter. But dietary cholesterol did not increase the levels of HDL-cholesterol in the butter-fed groups, but decreased in the corn-oil-fed groups. 3) Liver cholesterol concentrations were significantly higher in rats fed diets of corn-oil than those fed diets of butter. On the contrary, cholesterol concentrations of intestines were significantly higher in the butter-fed groups than the corn-oil-fed groups. However, in aortas, no significant differences were found.

• Journal of Food Hygiene and Safety
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• v.12 no.3
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• pp.240-253
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• 1997

The main problems contributing to food poisoning outbreaks in institutional settings and a home were reviewed and analyzed through the epidemiological investigations of food poisoning. The major documented factors included improper holding temperatures, inadequate cooking, poor personal hygiene, cross-contamination and contaminated equipment, food from unsafe sources, failure to follow food hygiene policies, and lack of education, training, monitoring and superivision. Usually more than one factor contributed to the development of an outbreak. (1) Use of improper holding temperatures was the single most important factor contributing to food poisoning. They included improper cooling, allowing a laps of time (12 hours or more) between preparing food and eating it, improper hot holding, and inadequate or improper thawing. Food thermometers were not used in most of the instances. (2) In inadequate cooking, the core temperature of food during and after cooking had not been measured, and routine monitoring was limited to recording the temperature of plated meals. Compared with conventional methods of cooking, microwave ovens did not protect against food poisoning as effectively. Centralized food preparation potentially increased the risk of food poisoning outbreaks. (3) Poor personal hygiene both at the individual level (improper handwashing and lack of proper hygienic practices) and at the institutional level (poor general sanitization) increased the risk of transmission. Person to person transmission of enteric pathogens through direct contact and via fomites has been noted in several instances. (4) Obtaining food from unsafe sources was a risk factor in outbreaks of food poisoning. Food risks were high when food was grown or harvested from contaminated areas. Possibilities included contamination in the field, in transport, at the retail site, or at the time it was prepared for serving. (5) Cross-contamination and inadequate cleaning/handling of equipment became potential vehicles of food poisoning. Failure to separate cooked food from raw food was also a risk factor. (6) Failure to follow food hygiene policies also provided opportunities for outbreaks of food poisoning. It included improper hygienic practices during food preparation, neglect of personnel policies (involvement of symptomatic workers in food preparation), poor results on routine inspections, and disregarding the results and recommendations of an inspection. (7) Lack of formal and in-service education, training, monitoring, and supervision of food handlers or supervisors were critical and perhaps neglected elements in occurrences of food poisoning.

• Food Science and Industry
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• v.53 no.3
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• pp.264-276
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• 2020

Ionizing radiation is one of the efficient non-thermal pasteurization methods. The US Food and Drug Administration (FDA) allows the use of ionizing radiation to a dose up to 10 kGy for controlling foodborne pathogens and extending the self-life of foods. Recently X-rays, generated on absorption of high energy electrons in an appropriate metal target, have been used commercially for sterilization purposes. X-rays have the advantages of higher penetration power than E-beams and absence of harmful radioactive sources, such as Cobalt-60 or Cesium-137 associated with gamma-rays. That is why it has continued to receive attention as an attractive alternative to gamma-ray or E-beam irradiation. In this article, the potential of X-ray irradiation for controlling foodborne pathogens in various food products and necessary pre-requisite knowledge for the introduction of X-ray irradiation to the Korean food industry will be provided.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.181-189
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• 2014

This study was conducted to investigate the effect of chicken skin and pork backfat on quality of Dakgalbi-taste chicken sausage as fat sources. The sausages were manufactured with 100% chicken breast without fat sources, 85% chicken breast meat with 15% chicken skin or 85% chicken breast meat with 15% pork backfat, respectively. Batters for production of chicken sausage were mixed with 5% Dakgalbi sauce and 4.92% ingredients (meat and lipid basis) for 20 min and then stuffed into casing. All cooked sausages were vacuum-packaged and stored at $4^{\circ}C$ for 14 days. Moisture and crude protein contents were higher in the control, and crude lipid content was higher in chicken sausage with pork backfat (p<0.05). Unsaturated fatty acids content and monounsaturated fatty acids/saturated fatty acids ratio of sausage with pork backfat were lower than those of control and sausage with chicken skin (p<0.05), which were influenced by fatty acids compositions of fat sources. The chicken sausage with pork backfat showed a lower hardness and chewiness, and higher springiness measured by food texture analyzer. The sausage with pork backfat had a high level of water holding capacity (WHC) during storage (p<0.05). In conclusion, Dakgalbi-taste chicken sausage containing chicken skin had higher unsaturated fatty acid compositions, but showed lower textural quality compared with that containing pork backfat.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.657-663
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• 2014

This study was conducted to investigate the difference in feeding habits of Red-Tongued Viper Snakes, according to available foods sources and areas. The effects of differences in food sources were found on Red-Tongued Viper Snake inhabited in the Jeju Island and its islet Gapado, from May 2006 to Nov. 2010. The food sources for the Red-Tongued viper snake population in the Jeju Island were found to be as follows: Chinese red-headed centipedes (Scolopendra subspinipes mutilans), Jeju Salamanders (Hynobius quelpaertensis), Japanese tree Frogs (Hyla japonica), Narrow-mouthed Toad (Kaloula borealis), Dybowski's Brown Frogs (Rana dybowskii), Black-spotted Pond Frogs (Rana nigromaculata), Smooth Skinks (Scincella vandenburghi), Asian Keelback Snakes (Amphiesma vibakari), Lesser White-toothed Shrews (Crosidura shantungensis), Hallasan Shrews (Sorex caecutiens hallamontanus), and Jeju Striped Field Mice (Apodemus chejuensis). This implies that Red-Tongued Viper Snakes mainly feed on amphibians, reptiles, and small mammals. Among these, amphibians occupied the highest portion at 55.2% followed by mammals at 20.7%, centipedes at 13.8%, and reptiles at 10.3%. On the contrary, Red-tongued viper snake population in Gapado only feed on Chinese red-headed centipedes and Smooth Skinks (S. vandenburghi). Since only a small amount of nutrient can be obtained from Chinese red-headed centipeds or Smooth Skinks, this feeding habit for Red-tongued viper snake would adversely effect on the growth or regeneration. The reason why Red-Tongued viper snake population in the Gapado mainly feed on Lizard and Centipedes in spite of relatively various available food sources, might be due to the low density of other food sources in the Gapado. Red-Tongued viper snake could be feeding on foods that are low in quality but are easily accessible, to minimize energy consumption on searching for other more nutritious foods. A snake tends to select the size of its food depending on the size of its own head. The positive correlation was found between the size of the heads of Red-Tongued viper snakes from the Jeju island and the diameter of their foods. The head size was larger in the males than females in viper snake population from the Jeju Island, which might effect on their selection of foods. However, no significant difference was found between the sizes of the head and the food in the Red-Tongued viper snake population from the Gapado. The findings of this study would provide meaningful data, which directly shows that even within the same viper species they choose different available food sources according to their inhabitance. This leads to their growth and adaptation to their environment which is beneficial for sustaining of its population.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.3
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• pp.539-547
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• 2015

This study investigated elementary school students' perception and recognition of soybean foods and assessed their intake levels of isoflavones. A survey was administered to 300 sixth grade students in Daegu. The amount of isoflavones consumed by students was estimated by food intake frequency and the 24-hour recall method based on their general dietary habits and perception of soybean foods. Subjects' mean height was 152.2 cm, mean weight was 45.2 kg, and body mass index was $19.4kg/m^2$. All subjects had knowledge of soybeans and most preferred bean-paste pot stew of all soybean-based foods. Students typically ingested isoflavones two or three times per week in the forms of tofu, bean-paste pot stew, and bean sprouts. The average amount of isoflavones consumed from soy foods was 26.43 mg/day (daidzein 9.27 mg/day and genistein 17.16 mg/day) as assessed by food frequency questionnaire and 30.83 mg/day (daidzein 13.63 mg/day and genistein 16.40 mg/day) by the 24-hour recall method, showing that the 24-hour recall method assessment amount was 4.4 mg higher than that of the food frequency questionnaire. The major food sources of isoflavones were soybean paste and soybeans. Those who were especially knowledgeable about soybean foods expressed the view that these sources were a good or affordable enriched source of isoflavones.

• Journal of the Korean Society of Food Culture
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• v.13 no.2
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• pp.107-118
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• 1998

A nutrition education program for teachers and caregivers of the preschool children can be most effective when it is based on a comprehensive needs assessment dealing with sociodemographic factors, dietary habits, and nutrition. The purpose of the present study was to investigate current dietary habits and nutrition knowledge of the teachers and caregivers of the day-care centers. Two hundred forty two teachers and caregivers were administered a questionnaire which was designed to ascertain informations on sociodemographic data, dietary habits and nutrition knowledge. Dietary habits of the teachers were found to be significantly different by sociodemographic variables; breakfast skipping/meal irregularities (age, p=0.011); frequency of snacking (education level p=0.031); preference for salty taste(age, p = 0.000, marital status p=0.038); preference for sweet tarte (age p=0.009); preference for vegetables (income level p=0.050); frequency of eating out (age p=0.028, marital status p=0.001); frequency of coffee drinking (age p=0.019). Daycare center teachers' nutrition knowledge level was found to be less than adequate expecially on nutrients that are liable to be deficient in young growing children and their food sources. Proportions of the teachers who answered correctly to the questions on foods rich in vitamin A, iron content of milk, bioavailability of calcium in plant foods were as low as 20.2%-54.5%. The most frequently used sources of nutrition information were mass media such as TV, radio, newspaper and magazines. Only 2.9% of the subjects reported that they obtain nutrition information from health professionals such as nutritionists/dietitians, physicians, and nurses. These findings are applicable at the planning and implementation stages of various nutrition programs for the improvement of dietary habits and nutrition knowledge of the teachers and caregivers of the daycare centers. Further studies are needed to investigate the effects of teachers' dietary of habits and nutrition knowledge on food habits of young growing children.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.522-534
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• 1996

The present study was conducted to investigate quality characteristics of Nochi made with malted barley flour with (Cl) and without hull (C2), comparing with Nochi that was treated with different sources of commercial amylases. There was higher level of moisture content (18.4%) in Nochi treated with fungal ${\alpha}$-amylase (FU) comparing with the other Nochi samples. However, Nochi that was treated with bacterial ${\alpha}$-amylase and ${\beta}$-amylase (BA-${\beta}$) had the lowest level of moisture content (11.2%). Nochi samples which were treated with thermostable ${\alpha}$-amylase and fungal ${\alpha}$-amylase(TE-FU) were different from traditional Nochi samples in mechanical characteristics. According to the results of sensory evaluation, Cl was similar to C2 except in cohesiveness and malt flavor. TE-FU and Bh-${\beta}$ were not different from traditional Nochi in cohesiveness, sweetness and overall desirability.