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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Korean Journal of Food Science and Technology
Journal Basic Information
Journal DOI :
Korean Society of Food Science and Technology
Editor in Chief :
Volume & Issues
Volume 34, Issue 6 - Dec 2002
Volume 34, Issue 5 - Oct 2002
Volume 34, Issue 4 - Aug 2002
Volume 34, Issue 3 - Jun 2002
Volume 34, Issue 2 - Apr 2002
Volume 34, Issue 1 - Feb 2002
Selecting the target year
The Effects of the Content of Pastry Margarine and the Number of Layers on The Texture and Color of the Puff Pastry
Han, Jang-Ho ; Kim, Seok-Young ; Lee, Si-Kyung ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 935~940
Effects of changes in the margarine content and the number of layers of the puff pastry on the color, hardness, and hardness change during storage of the final products were investigated. At equal content of pastry margarine, the lightness of the crust decreased slightly as the number of layers increased. Redness of the puff pastry with 70% margarine content and 81 layers was
and yellowness of puff pastry with 70% margarine content and 256 layers was 26. No significant differences were observed in the crumb change of the samples. The puff pastry with 90% margarine content and 144 layers showed the lowest hardness of
. Hardness of the products storage period increased significantly as the number of layers increased at equal pastry margarine content, whereas with same number of layers, decreased gradually as pastry margarine content increased. Results of the sensory evaluation reveal that the puff pastry with 90% margarine content and 144 layers was better than other samples. These results show the important of selecting the optimum number of layers during the manufacturing process to obtain the optimum condition for the mouthfeeling, flavor and overall acceptability of final products.
Characteristics of Propolis Extracts from Ethanol Extraction
Kim, Chong-Tai ; Kim, Chul-Jin ; Cho, Yong-Jin ; Choi, Ae-Jin ; Shin, Weon-Son ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 941~946
Propolis was extracted using various concentrations of ethanol at different solvent-sample ratios. Volatile flavor components of propolis were detected by GC/MS, and the principal components were analysed. The content of total flavonoids (TF) in propolis extract increased 2 to 14% with increasing concentration of ethanol in the extraction solvent from 20 to 50%, but deceased slightly between of 60 and 70%. The 70% ethanol extract of propolis had the strongest antimicrobial activities to E. coli, L. plantarum and S. cerevisiae. Propolis ethanol extracts (2 to 14%) showed higher antioxidative activities when added oil to soybean oil during storage at
Quality Evaluation of Dried Laver (Porphyra yezoensis Ueda) Using Electronic Nose Based on Metal Oxide Sensor or GC with SAW Sensor During Storage
Cho, Yen-Soo ; Noh, Bong-Soo ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 947~953
Two types of electronic nose were used for investigating the quality of dried lavers stored at 5, 15, and
RH of 32, 43, and 75%. The electronic nose is composed of metal oxide sensors, and GC is based on SAW sensor. Quality change in dried lavers was described in terms of the sensitivities
of the sensors. Principal component analysis (PCA) was carried out using data obtained from six metal oxide sensors. The first principal component scores were correlated with quality changes of dried lavers. As storage time increased, the stored laver cluster separated from that of fresh lavers. A chromatogram was obtained from GC based on SAW sensor. Olfactory image, A
image for pattern recognition, showed a significant difference between the stored and the fresh samples. Dried lavers during storage at
and 75% had bacterial counts of
after 8 day. Increase of microbial count correlated with the response of electronic nose
. Whereas, color values showed no correlation.
Comparison of Extractive Nitrogenous Constituents in the Three Species of Raw Bloody Clams, Scaphrca broughtonii, S. subcrenata, and Tegillarca granosa Extracts
Park, Choon-Kyu ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 954~961
Extracts of raw bloody clams, broughton's ribbed ark (Scaphrca broughtonii), subcrenated ark (S. subcrenata), and granulated ark (Tegillarca granosa), were analyzed and compared foe extractive nitrogen, free amino acids, combined amino acids, ATP and related compounds, quaternary ammonium bases, and guanidino compounds. The contents of extractive nitrogen in broughton's ribbed ark, subcrenated ark, and granulated ark were 479, 506, and 432 mg/100 g, respectively. Twenty-eight or twenty-nine types of free amino acids were detected in all three extracts, among which taurine,
, glutamic acid, and alanine were the major ones. The composition of the major extractive components such as free amino acids, combined amino acids, ATP and related compounds, TMAO, TMA, and creatine in the extracts were similar among the extracts, but their contents were different.
Studies on Microbiological and Chemical Characteristics of Gamma-Irradiated Soybean Powder
Kim, Hee-Yun ; Song, Kyong-Hee ; Hong, Jin-Hwan ; Kim, Dong-Sul ; Han, Sang-Bae ; Lee, Eun-Ju ; Kang, Kil-Jin ; Chung, Hyung-Wook ; Im, Moo-Hyeog ; Kim, Chang-Min ; Kwon, Yong-Kwan ; Chin, Myung-Shik ; Song, In-Hwan ; Byun, Myung-Woo ; Bae, Dong-Ho ; Shin, Il-Shik ; Ha, Sang-Chul ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 962~968
Effects of gamma-irradiation of 1 to 10 kGy on the microbial growth, contents of amino acids, fatty acids, and free sugars, and changes in acid values in soybean powder were studied. Irradiation doses at
inhibited the mold growth completely in two kinds of imported soybean powders. Contents of sulfur-containing amino acids, such as cysteine, in both soybean powders decreased with irradiation, whereas no significant changes in free amino acid and fatty acid contents of both soybean powders were observed. Free sugar contents of stachyose and sucrose in Chinese soybean powder decreased with increasing irradiation dose level, whereas, those of other sugars remained unchanged. Results of this study confirm that
irradiation can be safely applied to apply to soybean powder without causing significant quality deteriorations microbiologically and chemically.
Determination of Di-(2-Ethylhexyl) Adipate Migrated from Polyvinyl Chloride Wrap Film into Various Foodstuffs and Dishes Depending on Exposure Conditions
Lee, Young-Ho ; Gyoung, Young-Soo ; Lee, Keun-Taik ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 969~976
The migrating level of di-(2-ethylhexyl) adipate (DEHA) in PVC wrap to various foodstuffs dishes was determined using acetone/n-hexane as an extracting solvent. The recovery ratio of DEHA from various foodstuffs ranged from 81.3 to 91.2%. During storage at
for up to 3 days, highest migration of 22.9 mg/kg occurred with pork belly, an indication that increases in fat content, storage temperature, and storage time result in increasing DEHA migration. DEHA concentrations of various delivered dishes ranged between 6.9 and 29.8 mg/kg, and highest migration was observed in Chambbong, which had the highest fat content among samples. After microwave-reheating, which resulted in a tight contact between film and food samples, DEHA was not detected in rice and potato, whereas up to 158.8 mg/kg was detected in pizza. When the wrap film was not contacted with the surface of food, the migration was lowered. Migration levels of DEHA from PVC wrap film into samples under various exposure conditions often exceeded the limit value of
set by the European Union.
Studies on the Rapid Discrimination of Yellow Pigments Colored on Yellow Croakers and Natural Yellow Pigment of Croakers
Kim, Hee-Yun ; Hong, Jin-Hwan ; Kim, Dong-Sul ; Han, Sang-Bae ; Lee, Eun-Ju ; Lee, Jeung-Seung ; Kang, Kil-Jin ; Chung, Hyung-Wook ; Song, Kyung-Hee ; Park, Hye-Kyung ; Park, Jong-Seok ; Kwon, Yong-Kwan ; Chin, Myung-Shik ; Park, Hee-Ok ; Oh, Sae-Hwa ; Shin, Il-Shik ; Lee, Chang-Kook ; Park, Hee-Yul ; Ha, Sang-Chul ; Jo, Jae-Sun ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 977~983
This study was performed to establish the precise and rapid method to distinguish croakers through the pigment analysis of colored imported white croakers for adultration. We surveyed the coloring behaviors, extraction test by water and organic solvent and using pigments such as targeting, curcumine, and azo dye products. The pigment of yellow croaker is not stained on wet cloth or tissue which is rubbed on epidermis of yellow croaker and was not eluted in water extraction test, while adulterated pigments were easily extracted by water and acetone, but edible diluted yellow, Yellow No. 4 and Yellow No. 5 were not extracted. Reactive pigment was detected easily by extraction with water and dispersed pigment was also detected by extraction test. As a result of discoloring characteristics of carotene having similar structure to yellow croaker and azo dye by oxidation and reduction, azo dyes were not discolored by oxidation with sodium percarbonate or peracetic acid but that were discolored by oxidation with Fenton reagent after 1hr and by hypochlorite promptly. On the other hand, carotenes were not discolored by sodium precarbonate and Fenton reagent but discolored by sodium hypochlorite after 2 hr and by peracetic acid promptly. Azo dyes were discolored by reduction with sodium hydrosulfite and sodium carbonate but carotenes were not discolored by these reagents. This discoloring test was applicable to detect adulterated pigments and other marine product.
Oxidative Stability and Flavor Compounds of Sesame Oils Blended with Vegetable Oils
Joo, Kwang-Jee ; Kim, Jin-Ju ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 984~991
Oxidative stability and flavor of sesame oil blended with canola oil (Ca), corn oil (Co), and soybean oil (Sb) at ratios of 90 : 10, 70 : 30, and 50 : 50 (w/w), respectively, were evaluated. Oxidative stability of sesame oil increased with the addition of vegetable oils (10, 30, and 50% of Ca and Co, and 10% of Sb). Pyrazines, pyrroles, pyridines, and thiazoles, good contributors to the characteristic flavor of sesame oil, were also found in sesame oil blended with vegetable oil. The sensory evaluation showed that no difference was observed between sesame oil and sesame oil blended with 10% of Ca, Co or Sb, which showed higher oxidative stability.
Trace Metal Contents in Sugar Products and Their Safety Evaluations
Chung, So-Young ; Kim, Mee-Hye ; Kim, Jung-Soo ; Hong, Moo-Ki ; Lee, Jong-Ok ; Kim, Chang-Min ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 992~997
Contents of heavy metals in sugar products were estimated to provide a scientific basis for standardization of Korea Food Code of heavy metals. The contents of mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As) and copper (Cu) were determined in 285 sugar product samples using a mercury analyzer, atomic absorption spectrophotometer, and inductively coupled plasma spectrometer. The values of heavy metals in sugar products
were as follows:
. These results show that metal contents of domestic sugar products are similar to those reported in other countries. Weekly average intakes of lead, cadmium, and mercury from sugar products were
of Provisional Tolerable Weekly Intake set by FAO/WHO Joint Food Additives and Contaminants Committee to evaluate the safeties of sugar products.
Studies on the Determination Method of Hydrogen Peroxide in Foods
Lee, Tal-Soo ; Lee, Young-Ja ; Park, Jae-Seok ; Kwon, Yong-Kwan ; Hwang, Jung-Yeon ; Lee, Ju-Yeun ; Lee, Chul-Won ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 998~1001
Micro-LC method for the quantitative determination of hydrogen peroxide in foods has been established. This method was carried out on cation-exchange resin gel column using distilled water as mobile phase with 50 mM sodium sulfate as electrolyte. The detection was performed with an electrochemical detector (ECD) at 0.6 voltage. Under this analytical condition, the recovery rates of hydrogen peroxide in tomato and lemon were 98.3 and 97.4%, respectively. Among 28 food types, hydrogen peroxide concentrations were 0.6, 0.5, 1.9, 0.9, 0.5, 0.6, 0.9, 0.8, and 0.4 ppm in banana, peach, orange, strawberry, pepper, onion, cucumber, burdock, and egg plant, respectively, Whereas none was detected in remaing 19 samples.
Identification of Germination Properties for the Screening of Gamma-irradiated Beans
Oh, Kyeong-Nam ; Kang, Eun-Kyoung ; Park, Choon-Ran ; Yang, Jae-Seung ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1002~1006
Germination method was used to screen the biological changes in soybean, kidney bean, and red bean caused by gamma irradiation. Beans were irradiated at 0.1, 0.3, 0.5, 0.7, and 1.0 kGy. Ten beans of each sample were placed on moistened cotton and germinated at
. The root lengths were measured daily for 5 days. Root lengths of all beans grew continuously for 5 days, but the growth rate of irradiated beans decreased significantly from fourth day. Unirradiated beans showed the highest growth rate during 5 days of germination. Gamma-irradiated beans could be screened by measuring the daily growth rate and root length during germination.
Physicochemical and Organoleptic Properties of Starch Isolated from Gamma-Irradiated Acorn
Kwon, Joong-Ho ; Kim, Soo-Jin ; Lee, Jung-Eun ; Lee, Soo-Jeong ; Kim, Sung-Kon ; Kim, Jeong-Sook ; Byun, Myung-Woo ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1007~1012
Physicochemical and organoleptic properties were investigated in starch extracted from acorn gamma-irradiated for insect control. Hunter's color L, a, and b values were unchanged upon irradiation at 0.25 to 10 kGy. Scanning electron microscopic observation revealed no changes with gamma irradiation at 1 kGy, that is effective for disinifestation, whereas 10 kGy resulted in some clefts on the starch surface. X-ray diffraction analysis showed patterns of both amorphous and crystalline regions were not different among the treatment groups. Water-binding property, swelling power, solubility, and gelatinization patterns of starch were influenced by irradiation dose, but 1 kGy dose was not detrimental to the physicochemical properties. Textural parameters of acorn gel were relatively stable, but significant reductions were found in hardness, adhesiveness, and chewiness in samples irradiated at 3 kGy or higher. Rrsults revealed that irradiation at 1 kGy or lower could be applied for insect control without causing apparent changes in physicochemical and organoleptic properties of acorn starch.
Functional Activities of Microwave-Assisted Extracts from Flammulina velutipes
Kim, Hyun-Ku ; Choi, Yoon-Jung ; Kim, Kong-Hwan ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1013~1017
Functional activities of Flammulina velutipes extract including electron donating ability, nitrite-scavenging effect, and tyrosinase inhibition activity was examined. Extraction were carried out by microwave-assisted extraction (MAE) under different conditions including solvent and microwave power. Tyrosinase inhibition activity and nitrite-scavenging effect increased as microwave power increased during extraction. Total phenol content and electron-donating ability reached maximum at the microwave power of 90 W. Total polyphenol content and electron-donating ability increased as extraction time extended up to 15 min, with the highest tyrosinase inhibition obtained after 5 min extraction. Significantly higher tyrosinase inhibition activity was found in 99% ethanol extract, whereas greater nitrite-scavenging effect was observed in the water extract. The maximum nitrite-scavenging effect was found at pH 1.2 and decreased as pH increased.
Effect of Nitric Oxide Pretreatment on Quality of MA Packaged Peaches
Chung, Hun-Sik ; Kim, Jong-Kuk ; Kang, Woo-Won ; Youn, Kwang-Sup ; Lee, Ju-Baek ; Choi, Jong-Uck ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1018~1022
Effect of nitric oxide (NO) treatment on physiology and quality characteristics of peaches (Prunus persica L. Batsch) was determined. Peaches were treated for 4 hr with NO (0, 10, 100 ppm) gas under oxygen-free atmosphere at
, packaged with 0.05-mm LDPE film, and stored at
for 15 days. Treatment with 100 ppm NO reduced the ethylene production and the loss of flesh firmness in peaches, but did not affect soluble solids, titratable acidity, and surface color. Oxygen-free atmosphere induced the reduction of respiration rate and ethylene production. Modified atmosphere packaging retarded the loss of flesh firmness and surface greenness, but decreased soluble solids and titratable acidity regardless of NO treatment.
Relationship between RVA Properties and Film Physical Properties of Native Corn Starch and Hydroxypropylated Corn Starch
Han, Youn-Jeong ; Kim, Suk-Shin ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1023~1029
Relationship between RVA properties and physical properties of film made from native corn starch and hydroxypropylated corn starch at various levels of plasticizers was examinel. Tensile strength of the film decreased, but its elongation and water vapor permeability increased with increasing plasticizer concentration. The film with glycerol showed greater changes in physical properties than that with sorbitol. Hydroxypropylated starch film showed lower tensile strength, higher elongation, and higher water vapor permeability than the native starch film. Sorbitol resulted in films with relatively high tensile strength, whereas glycerol produced films with increased elongation. The most reliable parameters for the relationship between RVA properties and film properties were RVA peak viscosity, tensile strength, and water vapor permeability. Water vapor permeability and tensile strength had linear relationship with RVA properties. The tensile strength and water vapor permeability of film could be predicted using the RVA peak viscosity.
Effects of Salt and Soysauce Condiment on Lipid Oxidation in Broiled Mackerel (Scomber japonicus)
Ryu, Seung-Hee ; Lee, Young-Soon ; Moon, Gap-Soon ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1030~1035
Despite health benefits derived from fish oil, polyunsaturated fatty acids (PUFAs) contained in fish oil are susceptible to lipid oxidation. To determine the optimum condition for maintaining good quality cooked fish during storage, mackerels were broiled with salt or soysauce condiments, and the lipid oxidation during 12 days of storage at refrigerated condition was measured. Peroxide value of broiled mackerel group with salt significantly increased after immediate cooking and maintained higher value throughout the storage period compare to the soysauce-added group, but showed similar value to the control group. Conjugated diene content in the soysauce-group was lower than the control and salt-added groups. Malondialdehyde content of broiled mackerel increased twofold and showed similar values in soysauce-added and the control groups during storage, whereas increased in the salt-added group significantly. Fatty acid compositions of the three mackerel groups changed after cooking, whereas that of the control group was almost stable during storage. In comparison with raw mackerel, the ratio of PUFA and saturated fatty acids decreased significantly, and the content of n-3 family fatty acid decreased from 25.53 to 20.63% in salted broiled mackerel. Soysauce group showed no reduction of PUFA with increasing storage time and showed the highest ratio of n-3/n-6 among the three groups at 10 days storage. Results reveal soysauce condiment protects against lipid peroxidation of broiled mackerel. Maillard reaction products (MRPs) found in soysauce might be responsible for the inhibitory effect and is a good condiment for extending storage life of cooked fish containing high amount of PUFA.
Effect of Gas Absorbents on Quality Attributes and Respiration Characteristics of Mature-Green Mume (Prunus mume Sieb. et Zucc) Fruits during Storage at Ambient Temperature
Cha, Hwan-Soo ; Hong, Seok-In ; Chung, Myong-Soo ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1036~1042
During storage at
, the effect of gas absorbents, such as carbon dioxide scavenger, ethylene absorber, and their combinations, on respiration characteristics and quality attributes of mature-green Mume fruits packaged in
low density polyethylene (LDPE) film was examined. Changes in quality attributes of the fruits were observed in terms of weight loss, titratable acidity, pH, fish firmness, color, water-soluble solid, and chlorophyll contents. In the presence of ethylene absorber
, the physiological injury was remarkably suppressed, and there was no significant injury in Mume fruits at
for 10 days. Yellowing and softening were also noticeably reduced by the combination of plastic film packaging and inclusion of ethylene absorber. The respiration rate was slower in fruits sealed with ethylene absorber than in those with absorbent-free packaging. Using ethylene absorber, levels of oxygen and carbon dioxide were maintained at 2-3 and 7-8%, respectively, during storage at
for 10 days. The addition of carbon dioxide scavenger
, negatively affected the quality attributes and respiration characteristics of the fruits. Overall results showed that ethylene removal by gas absorbent in the film packages significantly prolonged the shelf life of the fruits at ambient temperature.
Quality Changes of Rosemary-Onion Kimchi by Packaging Materials during Storage
Chung, Dong-Ok ; Park, In-Duck ; Kim, Jeong-Ok ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1043~1047
This study was carried out to investigate the effect of packaging materials (Ny/PE, PET/Al/PE, PET/PE/LDPE/CPP, PET/Al/Ny/CPP films, and bottle) and packaging methods (atmosphere and vacuum) on the physicochemical properties of Onion Kimchi and Rosemary-onion Kimchi stored at
. Reducing sugar contents and pHs of Onion Kimchi and Rosemary-onion Kimchi decreased, whereas levels of titratible acidity and vit C contents increased with increasing the storage time. The fermentation of Rosemary-onion Kimchi was slower than that of Onion Kimchi. PET/PE/LDPE/CPP film was the most effective for Onion Kimchi packaging among all packaging materials tested.
Effects of Additives on Quality Attributes of Minced Ginger During Refrigerated Storage
Choi, Min-Seek ; Kim, Dong-Ho ; Lee, Kyung-Hae ; Lee, Young-Chun ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1048~1056
Quality of fresh ginger deteriorates rapidly during low temperature storage, and its storage life is short due to sprouting and microbial spoilage. The objectives of this research were to develop, using additives, a minced ginger product, which could maintain acceptable quality for over 30 days, and to investigate its quality changes during the cold storage. Storage stability of minced ginger product was investigated from the standpoint of the inhibition of brown discoloration, gas formation and liquid-solid separation. Fresh ginger was peeled and ground to produce minced ginger (control). Sodium bisulfite, L-cysteine, NaCl, sodium benzoate, modified starch, and/or xanthan gum were added to the control to minimize quality loss during storage, and to develop an optimum formula (A) of minced ginger. Samples were packed in Nylon/PE films, stored at
, sampled at a 30-day interval, and subjected to quality evaluations. Changes in pH, surface color, gas formation, liquid-solid separation, contents of free amino acids, free sugars, organic acids, and fatty acids were determined. Gas formation was effectively inhibited in samples with sodium benzoate and/or NaCl. Samples with xanthan gum did not result in liquid-solid separation. L-Cysteine and sodium bisulfite were effective in controlling discoloration. pH decreased during storage in all samples, except sample A. Organic acid contents of all samples increased during storage, with lactic acid content showing the highest increase. Free amino acid content decreased with increasing storage time. Free sugar content of all samples decreased during storage. Sensory results showed sample A maintained acceptable quality until 90 days of storage. These results suggest that quality of minced ginger could be successfully maintained with the additions of selected additives for up to 90 days.
Extraction of Triterpenoid Saponin (glycyrrhizin) from Liquorice by Co-solvent Modified Supercritical Carbon Dioxide
Kim, Hyun-Seok ; Kim, Byung-Yong ; Lim, Gio-Bin ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1057~1061
Effects of modifier and soaking on extraction of triterpenoid saponin (glycyrrhizin) from liquorice were examined using supercritical
at 50 MPa,
, and flow rate of 3 mL/min, and glycyrrhizin content was analyzed by HPLC. Additon of undiluted methanol, ethanol or isopropanol as modifier to
had little influence on extraction yield of glycyrrhizin. Soaking process using water increased the extraction yield as the sample to solvent ratio was increased. Addition of 70% methanol, ethanol or isopropanol to
significantly increased the extraction yields, with 70% methanol resulting in the highest yield. When water at 90% (w/w) of sample weight was used for soaking, the extraction yield and rate increased, 70% ethanol-modified
was almost equal to that obtained using 70% methanol.
Discriminating the Geographical Origin of Sesame Seeds by Low Field NMR
Rho, Jeong-Hae ; Lee, Sun-Min ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1062~1066
Low field NMR was employed to discriminate the geographical origin of sesame seeds from Sudan, China, and Korea. Sudan sesame seeds had the lowest contents of moisture and crude fat. Chemical components of Korean and Chinese sesame seeds were similar, whereas relaxation times
measeured through spin-lattice relaxation pluse techniques using 20 MHz NMR showed significant difference (p0.05). Canonical discriminant analysis could be used to identify the habitat of sesame seeds with over 90% accuracy of NMR results. Non-destructive and fast NMR techniques can be applied to classify Korean sesame seeds from those of other origins.
Thermal Inactivation Parameters of Peroxidase in Flammulina velutipes and Lyophyllum ulmarium
Lee, Kyun ; Kim, Kong-Hwan ; Kim, Hyun-Ku ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1067~1072
Peroxidase was used as a standard enzyme to determine optimum blanching conditions of Flammulina velutipes and Lyophyllum ulmarium. Crude peroxidase extracted from raw mushrooms had maximum activity at
and pH 5.5 (50 mM, potassium phosphate buffer) using substrates of
and p-Phenylendiamine. Thermal inactivation of the crude peroxidase followed the first-order kinetics. The activation energy and z value of the crude peroxidase for F. velutipes were 59.58 kcal/mol and
, whereas were 43.05 kcal/mol and
for L. ulmarium, respectively. On the basis of thermal kinetics parameters obtained, the optimum blanching conditions for F. velutipes and L. ulmarium were 1 min at
and 5 min at
, respectively. Activation energies and z values of peroxidases extracted from heat-treated mushrooms were 7.97 and 6.55 kcal/mol, and
for F. velutipes and L. ulmarium, respectively.
Antimicrobial Activities of Ethanol Extracts from Korean Bamboo Culms and Leaves
Baek, Jong-Won ; Chung, Sook-Hyun ; Moon, Gap-Soon ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1073~1078
Antimicrobial activities in 70% ethanol extracts of Korean bamboo trees were investigated. Among the antimicrobial activities against ten major strains causing food poisening, Wangdae (Phyllostachys bambusoides S. et Z.) showed the strongest activity among five major bamboo trees cultivated in Korea. Although all extracts showed relatively strong antimicrobial activities against Staphylococcus aureus and Streptoccus mutans, the extracts of bamboo culms showed stronger activities than that of bamboo leaves. MICs (minimal inhibitory concentration) of the extracts of Wangdae culm against Staphylococcus aureus and Streptococcus mutans were over
, respectively. The extract of Wangdae culm inhibited the growth of Staphylococcus aureus and Streptococcus mutans at over 0.5% concentration, and almost inhibited the growth of these strains at 1% level. The inhibitory effect of the extract of Wangdae culm was not destroyed by heating at 60, 80, and
for 60 min and at
for 15 min, suggesting that the component in the bamboo tree was very heat-stable. These results indicate that 70% ethanol extract of Wangdae culm could be useful as a natural antimicrobial agent.
Changes in the Components of Onion Vinegars by Two Stages Fermentation
Shin, Jin-Suk ; Lee, Oh-Seuk ; Jeong, Yong-Jin ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1079~1084
Changes in components of onion vinegar during two-stage fermentation were investigated. One sample group (A) was prepared with onion juice by extraction and concentration (15 brix), and the other group (B) was prepared using the same method but supplemented with sucrose. Comparison of glucose (4.1%), fructose (4.2%), and sucrose (0.6%) found in A as major sugars with those (3.2, 3.3, and 4.6%, respectively) of B showed a significant difference in sucrose concentration. During alcohol fermentation, S. kluyvery DJ97 consumed these sugars completely. At 36 hr of alcohol fermentation, concentrations of reducing and total sugars decreased to 0.5 and 0.8%, in A, and 0.4 and 0.6%, in B, respectively. No further changes were detected in the concentrations of these sugars thereafter. From 12 hr of fermentation, alcohol concentrations in groups A and B increased markedly, maximizing at 7.0% at 36 hr A and at 8.2% at 48 hr in B, and finally decreased thereafter in both groups. The detected alcohol components were ethanol, acetaldehyde, methanol, n-propyl alcohol, iso-butanol, and iso-amyl acohol. During acetic acid fermentation, the concentration of acetic acid as the major organic also increased significantly in both groups (4,776.72 and 4,894.93 mg% in A amd B, respectively). Other organic acid contents such as malic and succinic acids were higher in A than B. these results indicate that vinegar is better produced in onion extract with no sucrose supplementation based on its organic acid contents.
Strain Selection of Psychrotrophic Leuconostoc mesentroides Producing a Highly Active Dextransucrase from Kimchi
Eom, Hyun-Ju ; Seo, Dong-Mi ; Yoon, Hyang-Sik ; Lee, Hee-Bong ; Han, Nam-Soo ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1085~1090
Leuconostoc mesenteroides, the major bacterium in the initial phase of lactate-fermentation in kimchi, produces lactic acid, acetic acid, mannitol, and
. It also secrets dextransucrase, which catalyzes the transfer reaction of glucose from sucrose to maltose, synthesizing mainly panose (
, a probiotic oligosaccharide. To use the strain as a starer culture to produce high amount of panose during kimchi fermentation, we screened psychrotrophic strains showing fast growth rate at low temperature among the isolates of Leuconostoc sp. and selected two strains showing high dextransucrase activity. The strains were identified as Leuconostoc mesenteroides, which can be used as function added-starters for lactate-fermented foods.
Characteristics of Kiwifruit-Added Traditional Kochujang
Kim, Young-Soo ; Song, Geun-Seoup ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1091~1097
In order to improve palatability and quality of traditional kochujang, kiwifruit (Actinidia deliciosa) was added to traditional kochujang fermented for 3 months. Physicochemical and microbial characteristics were investigated during fermentation at
. Moisture contents of all treated kochujangs increased with increasing amount of kiwifruit added during fermentation. pH of kiwifruit-added kochujang was lower than that of the control kochujang, whereas no significant differences in titratible acidity was observed among all treatments. Crude protein and salt contents of kiwifruit-added kochujang were lower than those of the control, whereas no difference in crude fat contents were found. Ethanol and amino-nitrogen contents of 6 and 9% kiwifruit-added kochujang were higher than those of the control. Fructose contents of kiwi-added kochujangs were higher than that of the control. Major organic acids of kochujang were in the order of malic acid > citric acid > succinic acid > acetic acid > lactic acid > oxalic acid. Succinic acid level increased significantly during fermentation and was higher in kiwifruit-added kochujang than in the control. Bacterial cell counts of all treatments were not different, and viable cell count of yeast was slightly higher in kiwifruit-added kochujang only at the initial fermentation period. Sensory evaluation revealed that the addition of 9% kiwifruit was the optimum condition for improving kochujang quality.
Antioxidative Activities of Ethanol Extract Prepared from Leaves, Seed, Branch and Aerial Part of Crotalaria sessiflora L.
Kang, Myung-Hwa ; Choi, Chang-Suk ; Kim, Zang-Soo ; Chung, Hae-Kyung ; Min, Kwan-Sik ; Park, Chun-Geon ; Park, Hee-Woon ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1098~1102
Antioxidative activities of ethanol extracts of seed, branch, leaves, and aerial part of Crotalaria sessiflora L. were compared using in vitro experimental model. Solid contents of each extracts were 12.68, 16.28, 13.04, and 18.59 g/ 100 mL, and phenolic acid contents were
in branch, aerial part, seed, and leaves, respectively. Extracts prepared from leaves showed highest electron-donating ability toward DPPH. SOD-liked activities were 78.95, 70.85, 74.65, and 87.49% in aerial part, branch, seed, an leaves respectively. Extracts prepared from leaves showed 59.39% inhibitory effect on peroxidation of egg yolk lecithin.
Estimation of Concentrations in Foods and Their Daily Intake for Sorbic Acid in Korea
Kim, Hee-Yun ; Jang, Young-Mi ; Yoon, Hae-Jung ; Lee, Chang-Hee ; Park, Sung-Kwan ; Park, Sun-Young ; Shin, Il-Shick ; Lee, Jong-Ok ; Chin, Myung-Shik ; Lee, Chul-Won ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1103~1109
Mean concentration and daily intake of sorbic acid were estimated through the analysis of food samples obtained from Korea FDA and food sanitation inspection agency during
. Total number of samples were 14,129, among which the number of detected samples were 2,561 (detection rate was 18.13%). Contribution rate to total estimated daily intake (%) of sorbic acid in the categorized food were the highest in processed fish product. Total estimated daily intake
for age groups were the highest in
years old and ranged from 3.42 to 9.25 mg/person/day. Estimation of average food intake for each food item per person per day was based on data in national nutrition survey and national food disapperance data in 1998. Total estimated daily intake of sorbic acid was 20.40 mg per body weight of 55 kg. This value was 1.48% of acceptable daily intake evaluated by FAO/WHO and 33.03% of theoretical maximum daily intake.
Antimutagenic Effect of Extract of Eleutherococcus senticosus Maxim
Park, Jeong-Seob ; Oh, Chan-Ho ; Koh, Ha-Young ; Choi, Dong-Seong ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1110~1114
Antimutagenic effect of Eleutherococcus senticosus Maxim. on the mutagenicity induced by 2-AF and Trp-P-1 was studied using the Ames test with Salmonella typhimurium TA98 and TA100. In S. typhimurium TA98, the methanol extract
of root, stem, and leaf of E. senticosus showed inhibitory effects of 72.8, 70.0, and 78.7% on the mutagenicity induced by 2-AF, and 69.2, 64.9, and 59.4% by Trp-P-1, respectively, whereas none was observed in S. typhimurium TA100. These results suggest that the methanol extract of E. senticosus inhibits a frame shift mutation. And then the methanol extract further fractionated by chloroform, butanol, and water. The chloroform fractions of root, stem, and leaf showed strong antimutagenic effects induced by 2-AF and Trp-P-1 in S. typhimurium TA98, whereas none was observed in the butanol and aqueous fractions. The chloroform fractions of root, stem, and leaf showed antimutagenic effects of
in a dose-dependent manner.
Screening of the Antioxidative Activity, Antimutagenicity and Mutagenicity of the Ethanolic Extracts from Legumes
Chang, Su-Min ; Nam, Seok-Hyun ; Kang, Mi-Young ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1115~1122
To evaluate the physiological properties of 22 varieties of legumes, antioxidative activity, antimutagenicity against Mitomycin C, genotoxicity, and mutagenicity were tested. Ethanolic extracts of legumes had significant antioxidative activities in the tests of electron-donating ability to DPPH radical, hydroxy radical-scavenging activity, and inhibitory effect on lipid auto-oxidation model system. Soy sprout bean (green), mung bean, and small black bean (green) had excitatory effects on the growth of E. coli PQ 37 cell. Black bean and green soy bean had inhibitory effects on the mutagenicities of the cells. Rice bean, pea, mung bean, and bonavista bean showed antimutagenic activities against chemical mutagen, Mitomycin C. Thus, rice bean and mung bean were found to be appropriate auxiliary ingredients of rice cake and rice processing food for the promotion of health and augmentation of rice and legume consumptions.
Changes in pH, Sensory Properties and Volatile Odor Components of Kimchi by Heating
Ko, Young-Tae ; Baik, In-Hee ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1123~1126
Kimchi was ripened at
for 4 days and heated at
for 10 or 40 min. pH of the ripened kimchi was not changed by heating, whereas sensory properties of kimchi, including overall acceptability, acidity, taste, odor, and texture, were improved, particularly by
min-heating. Allyl mercaptan, methyl allyl sulfide, dimethyl disulfide, diallyl sulfide, diallyl disulfide, and ethanol were detected in the ripened kimchi. Volatile odor components except ethanol and methyl allyl sulfide were removed by heating at
min, and the ethanol content was further reduced by heating at
Survey of Biogenic Amines Contents in Commercial Beers
Kim, Jae-Hyun ; Ahn, Hyun-Joo ; Hong, Jin-Hwan ; Han, Sang-Bae ; Byun, Myung-Woo ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1127~1129
Fourteen commercial beers (eight domestic and six imported) were investigated for their biogenic amine contents. In all products, six biogenic amines, putrescine, cadaverine, tryptamine,
, spermine, and tyramine, were detected at different contents among the products, with the spermine content being the highest. Contents of cadaverine and
in domestic beers, and
and tyramine in imported ones were not significantly different. Results indicate that continuous monitoring of biogenic amine levels in commercial beers is needed to maintain chemical safety and qualities.
Screening of Domoic Acid, a Marine Neurotoxin, in Korean Shellfishes
Koh, Eun-Mi ; Kwon, Hoon-Jeong ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1130~1133
Domoic acid, and amnesic shellfish poison, is a neurotoxin frequently found in shellfishes. Guidance level for the consumable shellfish has been established as
domoic acid/g by Health and Welfare Canada and U.S. FDA. Domoic acid is produced by pennate diatom, a Nitzschia pungens f. multiseries ingested by the shellfish. Content of domoic acid in shellfish samples collected along the Korean shoreline from May to December of 1999 was analyzed. The collection included 1 Gastropoda (Murex shell) and 11 Bivalvias (oyster, little neck clam, orient hard clam, venus clam, surf clam, ark shell, hard-shelled mussel, pen shell, jack-knife clam, pink butterfly shell, and granulated ark shell). Samples were homogenized, extracted with 50% methanol, filtered, and analyzed by reversed-phase liquid chromatography at 242 nm with mobile phase consisting of 10% acetonitrile and 0.1% trifluoroacetic acid. Recovery of the HPLC analysis was 95.80% (
). All tested samples showed no domoic acid at the detection limit of 50 ng/g.
Selective Detection of Campylobacter jejuni, C. coli, Arcobacter butzleri and Helicobacter pylori by Polymerase Chain Reaction
Lee, Young-Duck ; Park, Jong-Hyun ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1134~1139
Campylobacter, Arcobacter, and Helicobacter, classified into the same rRNA superfamily VI by taxonomy, cause food-borne diseases, stomach ulcer, and gastric cancer. To detect each strain selectively from contaminated foods, PCR, multiplex-PCR, and restricion fragment length polymorphism (RFLP) were applied on Campylobacter, Arcobacter, and Helicobacter. The same PCR products could be detected using CHA primer targeted for 16S rRNA of Campylobacter, Arcobacter, and Helicobacter. To detect C. jejuni and C. coli from A. butzleri and H. pylori, pg50/pg3 primer targeted for fla A gene was used, and for A. butzleri, Arco2/Butz primer targeted for 23S rRNA was utilized. For H. pylori detection, icd1/icd2 primer targeted for isocitrate dehydrogenase gene was employed, and JEJ1/JEJ2 primer targeted for ceuE gene was effective for C. jejuni detection from the three strains. C. jejuni, C. coli could be separated from A. butzleri and H. pylori through PCR-RFLP using restriction enzyme Dde I. Such primers would be effective for detecting each strain selectively through PCR when C. jejuni, C. coli, A butzleri and H. pylori are contaminated together.
Observation of Molecular Relaxation Behavior of Glucose Powders with Different Structures and Particle Sizes Using Low Field Nuclear Magnetic Resonance (NMR)
Chung, Myung-Soo ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1140~1144
Molecular relaxation behaviors of crystalline glucose anhydrous, crystalline glucose monohydrate, and amorphous glucose with different particle sizes were observed by measuring spin-spin relaxation time constant
at the temperature range of
using temperature-controlled low field nuclear magnetic resonance spectroscopy. No change in
values of crystalline glucose anhydrous was observed throughout the temperature range, whereas
values of crystalline glucose monohydrate and amorphous glucose increased from around
, respectively. These results indicate that molecular mobility of crystalline glucose anhydrous does not change even at temperature higher than
and that the stability of powdered glucose could be improved by increasing the particle size of materials.
Analysis of Melatonin Content from Domestic Edible Plants
Kim, Seok-Joong ;
Korean Journal of Food Science and Technology, volume 34, issue 6, 2002, Pages 1145~1148
Melatonin, which is a hormone secreted from pineal gland of brain and known to prevent oxidative damages of various tissues, was analyzed in 26 domestic edible plants. For the preparation of melatonin fraction, 50% ethanol extract prepared from lyophilized plant powder was filtered and applied on TLC plate. Melatonin position on TLC developed with acetone was identified by fluorescence light and extracted with methanol. This methanolic fraction was injected into HPLC comprising ODS-A column, fluorescence detector, and mobile phase consisting of a mixture (30 : 70, v/v) of 70% ammonium acetate and methanol at a flow rate of 1.0 mL/min. Melatonin was identified at the retention time of 17 min. Results revealed that celery, leek, broccoli, and cauliflower had higher melatonin contents than others.