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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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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 26, Issue 6 - Dec 1994
Volume 26, Issue 5 - Oct 1994
Volume 26, Issue 4 - Aug 1994
Volume 26, Issue 3 - Jun 1994
Volume 26, Issue 2 - Apr 1994
Volume 26, Issue 1 - Feb 1994
Selecting the target year
Effects of Electrical Stimulation and Storage Temperature on ATP-related Compounds of Korean Native Cattle M. Semitendinosus Muscles.
Shin, Heuyn-Kil ; Lee, Yong-Woo ; Oh, Eun-Kyong ; Choi, Do-Young ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 343~347
The effects of low and high-voltage-electrical-stimulation and storing temperature on concentration of adenosine triphosphate (ATP) related compounds were studied in M. Semitendinosus muscles from Korean native cattle. Seven beef carcasses were split, the one side was electrically stimulated for 1 minute by using stimulator adjusted to 400 V/60 Hz as high voltage or to 110 V/60 Hz as low voltage while the other side served as an unstimulated control. Both side samples were incubated at
for 3 days. During storage, the concentration of ATP and its breakdown products were measured as a function of time. Significant differences (p<0.05) were observed in the variance of ATP, adenosine diphosphate (ADP) and inosine monophosphate (IMP) levels between low-or high-voltage-electrically stimulated muscles and unstimulated control at just after post-stimulation. The decomposition of adenosine compounds and the production of inosine compounds of low-voltage-electrically stimulated muscles were advanced more slowly than those of high-voltage-treatment muscles. With increasing storage time, the influence of electrical stimulation on changes of ATP related compounds in meat was decreased, but storing temperature begin to affect their concentration. Significant difference in the Hypoxanthine levels (p<0.05) was found of sample stored for 48 hours at
from samples stored at
regardless of electrical stimulation treatemt. IMP and inosine values in electrically stimulated muscles, higher than of a control during 72 hours of storage, indicated rapid production of flavor compounds in beef.
In vitro Study on the Functionality in Digestive Tract of Chitin and Chitosan from Crab Shell
Chang, Hyun-Joo ; Jeon, Dong-Won ; Lee, Su-Rae ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 348~354
Chitin and chitosan samples prepared from crab's shells under different conditions were compared for their physicochemical properties; and functionality in gastrointestinal tract by in vitro test. Their bulk density was in the range of
, and their viscosity was
in 0.1 chitin and
in 0.5% chitosan solution, showing a wide variation. The degree of deacetylation in chitosan samples as determined by IR spectral analysis was relatively high, showing
. At the same alkali concentration and reaction temperature, a longer reaction period gave an increased degree of deacetylation and lower viscosity. The water holding capacity of chitic substance became greater at higher soaking temperature; chitosan D at
showed the greatest value. Chitic substance with lower bulk density showed the higher water holding capacity. The retardation effect toward glucose absorption was higher in critic substances of lower density and higher water holding capacity; chitosan D showed the highest value of 38%. The retardation index toward bile acid absorption after 1 hour dialysis was
in chitic substances, 39% in pectin and 9% in cellulose. The retarding effect showed the highest value of 34% in chitosan D at 3% concentration.
Effects of Coagulant Concentration and Phytic Acid Addition on the Contents of Ca and P and Rheological Property of Soybean Curd
Park, Chan-Kyeong ; Hwang, In-Kyeong ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 355~358
The effect of concentration of coagulant and addition of phytic acid on physico-chemical properties of soybean curd was investigated. The results showed that the maximum protein yield in soybean curds was obtained with 0.029N Ca and the bound calcium per protein molecule significantly increased as the level of calcium increased. The highest precipitation of phytic acid occured at 0.029N Ca. When phytic acid was added to soybean milk during soybean curd preparation, the weight of soybean curd increased. The hardness of soybean curd was remarkably reduced by the increase of phytic acid level.
Volatile Flavor Components in Various Edible Portions of Calystegia japonica
Lee, Mie-Soon ; Choi, Hyang-Sook ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 359~364
Volatile flavor components from various edible portions of Calystegia japonica
were collected by simultaneous steam distillation-extraction(SDE) method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography(GC) and combined gas chromatography-mass spectrometry(GC-MS). Thirty nine volatile flavor components, including 21 hydrocarbons, 1 aldehyde, 4 ketones, 7 alcohols, 4 esters, 1 acid and 1 miscellaneous one were confirmed in leaves. Twenty six components, including 16 hydrocarbons, 2 aldehydes, 3 ketones and 5 alcohols were confirmed in stems, and 52 components, including 26 hydrocarbons, 2 aldehydes, 5 ketones, 13 alcohols, 1 ester, 1 acid and 4 miscellaneous ones were confirmed in roots. The kinds and amounts of volatile flavor components revealed different patterns depending upon various edible portions. Relatively greater numbers of volatile flavor components were identified in roots compared with other portions of this wild plant.
The Change of Anthocyanin and Spreadmeter Value of Strawberry Jam by Heating and Preservation
Park, Sung-Jun ; Lee, Jae-Ha ; Rhim, Jae-Ho ; Kwon, Kyung-Sup ; Jang, Hee-Gyu ; Yu, Mu-Yung ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 365~369
In attempt to explain the effect of heat processing on the product quality in manufacturing strawberry jam, the heat stability of anthocyanin in strawberry by addition of some sweetners was studied, and the effect of sucrose by concentration and pH were also investigated. The heat stability of anthocyanin was maximum at pH 2.5 when maintaining at
for 60 minutes initially, but it was shifted to pH 3.0 after additional heating of 120 minutes. When the corn syrup, sucrose and glucose were used as a sweetner for manufacturing strawberry jam, the results showed that heat stability of anthocyanin in corn syrup was higher than that in sucrose and fructose, and the optimum concentration of sucrose for heat stability was 66 Brix%. The results also showed that anthocyanin content in strawberry jam significantly decreased logarithmically at
, and spreadmeter value changed slightly at
storage but it was not significant.
The Effect of Water Activity and Temperature on the Retrogradation Rate of Gelatinized Corn Starch
Lee, Seog-Weon ; Rhee, Chul ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 370~374
The effect of water activity(Aw) and storage temperature on retrogradation of pregelatinized corn starch was investigated at various temperature of
. Samples stored at different water activity, i.e., 0.43, 0.52, 0.75, 0.83, 0.88 and 0.93 by means of saturated salt solutions. The rate of retrogradation was determines. by enzymic digestibility, and evaluated by Avrami equation. The degree of retrogradation during storage showed a great difference around Aw 0.8. At Aw 0.52 and 0.75 at all temperatures, retrogradation occurred slightly. The effect of water activity on retrogradation was much greater at
than 300. And at Aw 0.43, the degree of retrogradation after 3-week storage was smaller than 3.9%. The critical water activity of retrogradation was inferred as Aw 0.43. At each temperature, the degrees of retrogradation of gelatinized corn starch after 24-day storage were 30% at Aw 0.8 and Aw 0.9, and greater than 50% at the Aw above 0.9. At Aw below 0.8 the degree of retrogradation was about 20%. The rate constants of retrogradation according to Aw showed small differences at
, but showed a great difference at
. The value of exponent of Avrami was 1.0 regardless of temperature and water activity. And the rate constants of retrogradation increased with increasing Aw, but decreased with increasing temperature.
Purification and Properties of Cyclodextrin glycosyltransferase from Bacillus stearothermophilus KY-126
Kang, Sang-Mo ; Yoo, Si-Hyung ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 375~381
A bacterial strain No. KY-126, which produced extracellular cyclodextrin glycosyltransferase(CGTase), was isolated from soil and identified as Bacillus stearothermophilus KY-126. The enzyme was purified by the treatments of ammonium sulfate precipitation, DEAF-Sephadex, Sephadex G-100 column chromatography. The optimal pH and temperature for the enzyme activity were pH 5.5 and
, respectively. And the enzyme was stable at pH values from 6.0 to 11.0 at
for 30 min and stable up to
for 30 min.. The enzyme was inhibited by
. The molecular weight of the enzyme was estimated to be 67,000 by using SDS-PAGE. The maximum conversion from starch to cyclodextrin (CD) by CGTase was 43% and obtained at 6 hr reaction and the ratio of
, CD production at this time was 2.9 : 2.1 : 1.0.
Cold Storage and Quality Stability of Ascidian, Halocynthia roretzi
Lee, Kang-Ho ; Lee, Min-Ju ; Jung, Byung-Chun ; Hong, Byeong-Il ; Cho, Ho-Sung ; Lee, Dong-Ho ; Jung, Woo-Jin ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 382~388
Because of its restrictive harvest from spring to summer, It is necessary to preserve raw ascidians, Halocynthia roretzi, for the purpose of processing regardless of season. We evaluated low Temperature tolerance of ascidian and conditions for cold storage to secure the quality of the stock. To retard the browning of meat rapidly occurred after sucking, ascidians were blanched for 10 seconds in 10% boiling salt solution or dipped for 60 seconds in 0.2%
solution, respectively. The samples were stored in ice, at
for 85 days, respectively. Changes in VBN, glycogen, brown pigment formation, total carotenoid, nucleotides and their related compounds during the storage were determined, and sensory evaluation of quality was also practiced. VBN and brown pigment formation were rapidly increased. Glycogen was gradually decreased and then not detectable after 85 days in case of ice storage. Lipophilic brown pigment was higher than hydrophilic and rapidly increased during storage. The result of sensory evaluation showed that the ascidian treated in 0.2%
was good for 85 days of storage at
. Judging from the results of chemical experiment and sensory evaluation, the quality of ascidian treated in 0.2%
and stored at
was better than that of other samples.
Changes in Nitrogen Compounds of Traditional Kochujang during Fermentation
Kim, Young-Soo ; Shin, Dong-Bin ; Koo, Min-Seon ; Oh, Hoon-Il ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 389~392
Changes in free amino acids and amino nitrogen of traditional kochujang were investigated during 180 days of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, and Sachun kochujang prepared with wheat. Amino acids remarkably increased during fermentation were methionine, glutamic acid, isoleucine, leucine and tyrosine. However, regardless of kinds of kochujang major free amino acids were serine, aspartic acid, glutamic acid and proline. Glutamic acid was noted as the most contributing to the savory taste of kochujang in relation to the increasing ratio and content among tree amino acids during fermentaion. The correlation coefficent between totals of free amino acids and the contents of amino nitrogen were relatively high (0.87
Processing of Powdered Smoked-Dried Anchovy Soup and Its Taste Compounds
Oh, Kwang-Soo ; Lee, Hyeung-Joo ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 393~397
The study was carried out to develop the powdered smoked-dried anchovy products as a natural flavoring substance. The processing conditions, chemical and taste compounds of products were as follows: The raw anchovy were washed, and then boiled 5 minutes in
NaCl and 1.0% sodium erythorbate solution. Boiled anchovy were smoked in smoking house at
for 4 hours as the first stage, and then increased temperature up to
as the second stage, and finally smoked 8 hrs at
to maintain the moisture content between 9 and 10 percent. The smoked-dried anchovy were pulverized and screened to be 50 mesh of particle size, and finally packed in PET/Al/CPP film bag. The moisture, crude lipid content and salinity of powdered smoke-dried anchovy were 9.4%, 9.6% and 6.9%, respectively. Fatty acid composition of product was mainly consisted of polyenes (43.4%) such as 22 : 6 and 20 : 5, followed by saturates (36.9%), monoenes (19.7%). The principal taste compounds of product were IMP, 466.5 mg/100g; free amino acids such as His, Tau, Pro, Lys, Ala and Glu, 1179.2 mg/100g; non-volatile organic acids such as lactic acid and succinic acid, 617.9 mg/100g; total creatinine, 595.9 mg/100g; small amount of betaine and TMAO. To make a instant soup, it was desirable for taste of products that powdered smoked-dried anchovy were mixed with 20% salt, 4.0% sugar, 3.0% MSG, 1.0% onion powder, 1.0% garlic powder and 1.0% black pepper.
Properties of Crude Amylase Isolated from Pine Nut
Kim, Jong-Sang ; Seog, Ho-Moon ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 398~402
The participation of thermostable amylase in the decrease of viscosity of pine nut's porridge was investigated using the crude enzyme obtained from ammonium sulfate fractionation of pine nut extracts. The fraction precipitated at
saturation of ammonium sulfate had the highest specific activity of the enzyme.
activity was maximal at
, pH 5.4. Amylograph data showed that addition of the enzyme to rice flour resulted in the significant decrease of its viscosity, suggesting the existence of thermostable
in pine nut.
Changes in Physicochemical Properties of Industry-type Kochujang during Storage
Jung, Sung-Won ; Kim, Young-Ho ; Koo, Min-Seon ; Shin, Dong-Bin ; Chung, Kun-Sub ; Kim, Young-Soo ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 403~410
Changes in physical and chemical characteristics of industry-type kochujang were investigated during 105 days of storage at
. Reducing sugar content of kochujang decreased rapidly up to the 15th day of storage and then decreased slowly thereafter. Total free amino acid contents decreased by 22.3% after 60 days and by 35% after 90 days of storage. The activities of amylase and protease did not show any significant changes, however, the activity of neutral protease increased slightly. The moisture content and water activity of the kochujang decreased linealy during storage and the correlation coefficient between the moisture content and water activity showed 0.964. Apparent viscosity of kochujang increased with an increase in storage time. It was found that water activity was more responsible for the increase of apparent viscosity than water content.
Optimization of Growth Medium Composition for Overproduction of Bacillus licheniformis Amylase in Recombinant Escherichia coli
Nam, Seung-Hun ; Lee, Woo-Jong ; Byun, Tae-Gang ; Seo, Jin-Ho ; Park, Kwan-Hwa ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 411~416
The research is concerned with optimization of growth medium composition in an attempt to improve the product yield of Bacillus licheniformis amylase (BLMA) in recombinant E. coli containing the BLMA gene. BLMA has the catalytic activity of producing branched oligosaccharides from starch. The medium optimization was performed in flask cultures based on the Box and Wilson method. The optimized medium is composed of tryptone 18.0 g/l, yeast extract 22.4 g/l, NaCl 5.3 g/l and glucose 2.1 g/l. In a jar fermenter culture with the conventional LB medium, the recombinant E. coli yielded 1.39 g/l of final dry cell mass and 5.11 U/ml of enzyme activity. In the optimized medium, however, the final cell mass was increased to 6.01 g/l and the enzyme activity to 23.2 U/ml. Medium optimization improved cell mass by 4.3 times and enzyme activity by 4.5 times. Such an increase in enzyme activity is mainly due to an enhancement of cell mass.
Screening for the Antioxidants in Unused Marine Resources by the Polarographic Method
Cho, Soon-Yeong ; You, Byeong-Jin ; Chang, Mi-Hwa ; Lee, Soo-Jung ; Sung, Nak-Ju ; Lee, Eung-Ho ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 417~421
To detect naturally occurring antioxidative components from unused marine resources, the screening test for the antioxidants containing in starfish, ascidian skin, cuttlefish ink, echinoid skin, Sargassum horneri, Agarum cribrosum, Odonthalia corymbifera and Desmarestia ligulata was carried out. The ether, acetone and methanol fractions successively extracted from Odonthalia corymbifera were very effective on prevention of the nonenzymatic lipid oxidation and their
, (a concentration to inhibit 50% of control lipid oxidation rate) were
, respectively. The water and methanol extracts obtained from cuttlefish ink also revealed strong antioxidant effect and their
The Quality of Salted and Semi-Dried Mackerel Processed by Cold Osmotic Dehydration during Storage
Lee, Jung-Suck ; Joo, Dong-Sik ; Kim, Jin-Soo ; Cho, Soon-Yeong ; Lee, Eung-Ho ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 422~427
The quality of salted and semi-dried mackerel prepared by cold osmotic dehydration using a high osmotic pressure resin during storage at
was evaluated. The moisture contents in salted and semi-dried mackerel decreased in. range of 4 during storage. The brown pigment formation content and peroxide value of salted and semi-dried mackerel prepared by osmotic dehydration were more lower than those of salted and semi-dried mackerel prepared by traditional drying methods such as sun-drying, hot-air drying and cold air drying. The viable cell count and histamine contents of cold osmotic dried products were much lower and revealed a tendency to increase during storage, but even these values after storage of 15 days showed that the salted and semi-dried mackerel was safety in respect of food sanitation. The ratio of saline soluble nitrogen to total nitrogen in cold osmotic dried products were higher than that of traditional dried products during storage. Judging from the results of chemical and sensory evaluation, shelf-life of salted and semi-dried mackerel by cold osmotic drying were more longer than that of salted and semi-dried mackerel prepared by traditional drying.
Properties of Modified Rice Starch by Physical Modification
Kum, Jun-Seok ; Lee, Hyun-Yu ; Shin, Myoung-Gon ; Yoo, Mi-Ra ; Kim, Kil-Hwan ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 428~435
Properties of modified rice starches prepared in drum drying and extrusion were evaluated to use for effective utilization. Blue value was the lowest (p<0.05) for waxy rice starch and L value was decreased after modification of starches. Water solubility index was the highest for modified starches prepared in extrusion, while water absorption index was the highest for modified starches prepared in drum drying. Cold-Water-Solubility was the highest (p<0.05) for modified rice starch prepared in drum drying (RD). Consistency index of RD was drastically increased as shear rate increased and yield stress was the highest for RD. Results of Gel Permeation Chromatography showed that starch components were broken down into lower molecular weight materials and amylose are degraded by modification. Changes in the X-ray diffrectometry pattern indicated the transformation of granule into an amorphous state during modification and illustrated V-type.
Antigenicity of Whey Protein Hydrolysates Against Rabbit Anti
Ha, Woel-Kyu ; Juhn, Suk-Lak ; Kim, Jung-Wan ; Lee, Soo-Won ; Lee, Jae-Young ; Shon, Dong-Hwa ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 436~441
To investigate the lowering effects of in vitro enzymatic hydrolysis by the treatment of chymotrypsin, trypsin, pancreatin, or protease from Aspergillus oryzae on the antigenicity of whey protein isolate (WPI) against rabbit anti
antiserum, competitive inhibition ELISA (cELISA) and passive cutaneous anaphylaxis (PCA) test using guinea pig were performed. The results of cELISA showed that the monovalent antigenicity of the whey protein hydrolysates (WPH) to the antiserum was decreased to
and less by the hydrolysis. The monovalent antigenicity of the WPH hydrolyzed by trypsin, or protease from Asp. nryzae was much lowered by the pretreatment of heat denaturation. The antigenicity of the WPH hydrolyzed by chymotrypsin, trypsin, or pancreatin was much lowered by the pretreatment of pepsin. Especially, the antigenicity of TDP (trypic hydrolysate with pretreatment of heat and pepsin) was found almost to be removed. However, there was not consistency between degree of hydrolysis(DH) and the monovalent antigenicity of the WPH. By the heterologous PCA it was found that all of the PGPH lost the polyvalent antigenicity regardless of the pretreatments although WPI and
had the positive high antigenicity. The results suggested that the peptides derived from
in WPH could bind specific antibodies but they could not induce allergy. Therefore, it was elucidated that the allergenicity of
in whey protein could be destroyed easily by the enzymatic hydrolysis.
Effect of Various Mixing Ratio of Non-glutinous and Glutinous Rice on Physical and Rheological Properties of Extrudate
Kum, Jun-Seok ; Kwon, Sang-Oh ; Lee, Hyun-Yu ; Lee, Sang-Hyo ; Jung, Jin-Hyub ; Kim, Jun-Pyong ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 442~447
Effect of different mixing ratio of non-glutinous and glutinous rice on physical and rheological properties of extrudate prepared in a single screw extruder were examined. The extrusion conditions in term of screw speeds, moisture content and die temperature were 258 rpm, 18% and
, respectively. The resisdence time distribution of the most of materials were within 30 second and small portion of them went up to 80 second. The expansion ratio was the highest value (2.93) for 70% of glutinous rice in the mixture, while the lowest value for 100% of non-glutinous rice. Breaking strength was in the range between 1,051g and 1,117g for
of glutinous rice in the mixture, while the lowest value (737g) for 80%r of glutinous rice. As the amount of glutinous rice increased, L and a values were increased and b value was decreased. The uncooked cold paste viscosity had 400 B.U. for 100% non-glutinous rice , while no peak for the 100% glutinous rice. As the amount of glutinous rice increased up to 100%, the water absorption index (WAI) was decreased, while water solubility index (WSI) was increased. The rheological properties of extrudate were accounted by the law of Oswald. The flow behavior index of extrudate was less than 1.0, which showed pseudoplastic behavior. Yield stress was the highest value for 20% of glutinous rice in the mixture and the lowest value for
of glutinous; rice. Number of air cell was between 128 and 159 for
of glutinous rice in the mixture, while
of glutinous rice. The degree of shapefact was increased more when the mixtures of glutinous and non-glutinous rice was used than when glutinous or non-glutinous rice was only used.
In-line Image Processing System for Measurement of Extrudate Thickness
Won, Chee-Sun ; Lee, Seung-Ju ; Han, Ouk ; Mok, Chul-Kyoon ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 448~452
This paper presents a computer image processing system, which measures the thickness of the food extrudate on a real-time basis. The image processing system was established with a CCD camera, an image grabber, and a 486 PC. The image obtained by the system was analyzed by a devised C-program, specially designed for the real-time thickness measurement of the extrudate. Experimental results showed that the proposed computer algorithm yielded an accurate measurement of the thickness of the food extrudate within 1 second.
Changes of Physicochemical Characteristics and Development of New Quality Indices for Industry-produced Koji Kochujang
Kim, Young-Soo ; Cha, Jin ; Jung, Sung-Won ; Park, Eun-Ji ; Kim, Jung-Ok ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 453~458
43 Kinds of physicochemical characteristics of koji kochujang prepared by a standardized industrial process were determined and analyzed statistically during storage for 105 days at
. The characteristics which showed significant correlation with storage period after preparation of kochujang were 12 items, which included sensory preference for flavor and taste, Hunter tristimulus values(
), HMF, capsanthin, formol nitrogen, threonine, water and water activity. Seven of the items were related with color attributes of kochujang. Especially, tristimulus values showed significant correlation with sensory preference for color of kochujang. In this regard, tristimulus values should be recommended as new quality indices of national standard for industry-produced koji kochujang. Means and standard deviations of tristimulus values of 27 kinds of industry-produced koji kochujang in the market were
Effect of Retrograde Restraint of Rice Cake Using Raw Starch Saccharifying
from Bacillus polymyxa No. 26
Sohn, Cheon-Bae ; Lee, Sang-Mee ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 459~463
To improve the quality of rice-cake(Cholpyon), raw starch saccharifying (
from Bacillus polymyxa No. 26 was used in process of raw rice-cake production. 30g of raw rice flour was incubated with
RS units of the enzyme for 5 hr at
, and then steamed and stored for 40 hr at
. In instrumental analysis, control group, which was incubated without addition of (
, was completely hardened after incubation for
. In contrast, enzyme-treated group was not retrograded, and showed a great differences in hardness, cohesiveness and chewiness. On the other hand, in sensory analysis, the effect of the enzyme treatment was higher values of hardness, moistness, and sweetness than these of control group. Therefore, these results clearly suggested that
was fully active to degrade raw rice starch in process of rice-cake production, resulting in improvement of starch retrogradation, good digestibility, and taste.
Antimicrobial and Antioxidative Activities of Solvent Fraction from Humulus japonicus
Park, Seung-Woo ; Woo, Cheol-Joo ; Chung, Shin-Kyo ; Chung, Ki-Taek ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 464~470
The biological activities of Humulus japonicus were extracted by water and methanol. Methanol was better solvent than water in the extraction for antimicrobial activities against six different species of bacteria and two yeasts. The methanol extract was systematically fractionated with various organic solvents which have different polarities. From the result of antimicrobial activities against six species of bacteria and two species of yeasts, methanol extract was superior to water extract. The methanol extract of Humulus japonicus showed antimicrobial activity against the all species of microorganisms tested except Escherichia coli . The butanol fraction of methanol extract showed antimicrobial effect on the all species tested. The minimal inhibition concentration(MIC) of the butanol fraction on the growth of microorganisms was ranged between
. The water extract of Humulus japonicus did not show inhibition of the activity of trypsin but methanol extract showed inhibitory activity. The chloroform fraction of methanol extract showed comparatively higher trypsin inhibitory activity than other fractions. The concentration of 50% inhibition
by chloroform fraction was 1.0 mg/ml. Enzyme-inhibitor complex formation was above 90% of the while for 20 min. It was revealed that methanol extract of Humulus japonicus inhibited peroxide production of lard and soybean oil as substrate by antioxidative test. The chloroform fraction of methanol extract had the highest activity. When 0.2% of chloroform fraction was added, induction period of soybean oil and lard were extended 15, 9 days, respectively.
Changes in Physicochemical Characteristics of Barley Leaves During Growth
Kim, Kyung-Tack ; Seog, Ho-Moon ; Kim, Sung-Soo ; Lee, Young-Tack ; Hong, Hee-Do ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 471~474
Growing barley leaves with
length were analyzed for chemical constituents including moisture, crude fiber, protein, fat, ash, free sugars, free amino acids, chlorophylls, vitamin C and minerals. During the growth of barley leaves, moisture content decreased, while crude fiber gradually increased. Protein, fat and ash contents of barley leaves remained relatively unchanged. Chlorophyll content increased to a maximum value at the leaf length of 20 cm, and then declined. Minerals of barley leaves were abundant in the following order of K>Ca>P>Na>Mg. Vitamin C content, showing the similar trend to chlorophyll, was the highest at the leaf length of 20 cm. Major free sugars present in growing barley leaves were identified as glucose, fructose and sucrose. All the free sugars reached their maximum values at 20 cm and they were reduced thereafter. Total amount of free amino acids varied from 803 mg% at the Barley stage of l0 cm to 1038 mg% at the later stage of 50 cm. Changes in content for each amino acid were variable to some extent.
In Vitro Digestibility of Chemically Modified Starches and Ramen Starches
Kim, Sue-Yeon ; Lee, Su-Rae ;
Korean Journal of Food Science and Technology, volume 26, issue 4, 1994, Pages 475~478
The hydrolyzability of chemically modified starches and ramen staches was determined by hog pancreatic
in vitro test. The extents of hydrolysis were 64.5% and 59.3% in native and acetylated potato starch, 70.5% and 60.4% in native and hydroxypropylated corn starch, and 65.2% and 57.3% in native and hydroxypropylated high amylose corn starch, respectively. The hydrolysis extents of waxy corn starch derivatives were shown in the descending order of pregelatinized (74.3%)>native (72.1%)>acetylated (66.5%)>acetyl distarch adiphate (56.4%)>hydroxypropyl distarch phosphate (50.7%). In the test on starches of container and regular ramen cooked by practical way, no significant difference was observed between ramen products of five different makers. Although the hydrolysis rate and extent of chemically modified starches were lower than those of native starches, the digestibility of ramen seemed to be not affected in the common diet as the use level of modified starch was relatively low.