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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 16, Issue 4 - Dec 1984
Volume 16, Issue 3 - Sep 1984
Volume 16, Issue 2 - Jun 1984
Volume 16, Issue 1 - Mar 1984
Selecting the target year
Fatty Acid Composition of Lipids obtained from Korean Soybean Varieties
Yoon, Tai-Heon ; Im, Kyung-Ja ; Kim, Dong-Hoon ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 375~382
The fatty acid compositions of lipids from five local varieties and three imported varieties of soybean were determined. Total and free lipids of the samples were extracted with chloroform-methanol mixture (2:1, v/v) and ethyl ether, respectively. The ether-extracted samples were extracted again with water saturated n-butanol to obtain bound lipids. The average percent contents of the lipid fractions were 21% (total), 18% (free), and 3.3% (bound). The results indicated that seven fatty acids (10:0, 12:0, 14:0, 16:0, 17:0, 20:0 and 22:0) were identified as minor fatty acids for all the varieties examined in this study. The relative contents of 18:2 were the highest (50.1-59.7%) in all the lipid fractions, and the contents in total and free lipids were in-fluenced by the local varieties. Little difference in fatty acid composition was noted between the total and free lipids of the samples. Total and free lipids contained more 18:1 (about 10%) and less 16:0 (about 40%) and 14:0 (about 34%) than did the bound lipids. The relative percent contents of 18:3 in the total, free and bound lipids were on average 8.9, 9.0, and 7.3 percents. The content in the total lipids of Gwanggyo varieties showed the highest level (11.1%), and in the bound lipids of Eundaedoo varieties the lowest (6.0%). In case of the total and free lipids, those varieties which showed higher relative contents of 18:1 generally had lower relative contents of 18:2 and 18:3.
Glycoalkaloid Content as influenced by Varieties, Parts and Weight of Potatoes
Hwang, Chun-Sun ; Lee, Sung-Woo ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 383~387
The difference of glycoalkaloids content on various parts of May Queen and Irish Cobbler potatoes was determined.
were isolated from the glycoalkaloids by use of high performance liquid chromatography. It was found that the 99% of the total glycoalkaloids was existent in cortex part of all varieties. Glycoalkaloids content was higher in apical or basal part than the middle part.
content of the cortex showed no differences among parts of the potato in both varieties.
was not detected in medulla part. The potatoes were classified into 4 groups depending on the weight and the glycoalkaloids content of the middle part. As the weight of the potato decreased the glycoalkaloids content of cortex part increased. Glycoalkaloids content was lower in medulla part and no constant tendency was observed.
Change in Glycoalkaloid of Potatoes during Storage
Hwang, Chun-Sun ; Lee, Sung-Woo ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 388~391
The purpose of this report was to investigate change in glycoalkaloid content (
) which contained in the cortex and medulla part during storage of two varieties of potato, Irish Cobbler and May Queen at
. The tubers of both varities stored at
showed sprouting and
contained in cortex part increased, particularly the extent of increase was more noticeable in May Queen than in Irish Cobbler. The content of glycoalkaloid in tubers stored at
also increased continuously. A small amount of
was detected in the medulla part of both varieties, but
was not detected at all.
Enzymatic Characteristics of Two Forms of the Purified Glucoamylase from Rhizopus oryzae
Hou, Won-Nyong ; Chung, Man-Jae ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 392~397
These experiments were conducted to investigate general enzymatic characteristics of two forms(glucoamylase I and glucoamylase II) of the purified glucoamylase produced by Rhizopus oryzae. Molecular weights of glucoamylase I and glucoamylase II estimated by Sephadex G-100gel filtration, were approximately 101,000 and 115,000, respectively, and those estimated by SDS-polyacrylamide gel electrophoresis being 120,000 and 127,000, respectively. Isoelectric points of the above enzyme were pH 7.25 and pH 7.75. The optimum temperature was
and the enzyme was stable below
. Optimum pH of both glucoamylase I and glucoamylase II was about pH 5.0. The stable pH range of them were pH 3.5-8.0 and 4.5-8.0, respectively. Michaelis constants of glucoamylase I and glucoamylase II toward souluble starch were 4.545 mg/ml and 5.560 mg/ml, respectively.
, p-CMB and IAA were inhibitors of glucoamylase I and
, p-CMB and IAA were inhibitors of glucoamylase II.
Hydrolysis of Various Substrates by Two Forms of the Purified Glucoamylase from Rhizopus oryzae
Hou, Won-Nyong ; Chung, Man-Jae ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 398~402
These experiments were conducted to investigate the substrate specificity, the hydrolysis products on the various carbohydrates and the hydrolysis rate on the various raw starches of the two purified glucoamylase produced by Rhizopus oryzae. Both of the glucoamylases hydrolyzed amylose, amylopectin, glycogen, soluble starch, pullulan, maltose, maltotriose, maltotetraose, maltopentaose, maltohexaose, maltoheptaose and maltooctaose, but did not act on
, raffinose, sucrose and lactose. When the reaction mixture of glucoamylase and polysaccharides were incubated
for 32 hours, glucoamylase I hydrolyzed amylopectin, soluble starch and amyloses completely, but hydrolyzing glycogen up to only about 88%. Glucoamylase II hydrolyzed the previous four polysaccharides up to about 100%. Both of the glucoamylases produced only glucose for various substrates and did not have any
transferase activity. Both of the glucoamylases hydrolyzed raw glutinous rice starch almost complety, wheras they acted on raw potato starch, raw green banana starch, raw arrow root starch, raw corn starch, raw yam starch and raw high amylose corn starch weakly. Glucoamylase II hydrolyzed raw starches at the higher rate than glucoamylase I.
Interaction of Phytic Acid with Minerals during Meju Preparation
Kang, Hyeon-Ju ; Park, Eun-Soon ; Yoon, Sun ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 403~407
The purpose of this study was to investigate the changes of phytic acid content and phytase activity and the interactions between phytic acid and minerals in the preparation of Meju (fermented steamed soybean mash with molds). Meju contained significantly lower phytic acid and higher phytase activity than both raw and cooked soybeans. This seems to be the result of degradation of phytic acid by phytase produced during preparation of Meju by Aspergillus oryzae. Fe, Zn, Ca contents of soybeans were not changed either by cooking or fermentation. However, these minerals in the retentate of ultrafiltration were significantly lower in Meju than in raw and cooked soybeans. This result indicated that there are lower mineral-phytic acid complex in Meju than in raw and cooked soybeans, which might contribute to higher bioavailability of these minerals in Meju.
Effect of Gamma Irradiation on the Physiological Characteristics of Garlic Bulbs During Storage
Kwon, Joong-Ho ; Yoon, Hyung-Sik ; Sohn, Tae-Hwa ; Byun, Myung-Woo ; Cho, Han-Ok ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 408~412
This study was intended to investigate the physiological effect of gamma irradiation at 50, 100 and 500 Gy on the garlic bulbs stored at low temperature of
and a relative humidity of 70-80%, and room temperature of
and a relative humidity of 75-85%, respectively for 10 months. Irradiation treatment stimulated temporary the respiration of garlic, which was greatly affected by storage conditions later. Sprouting of garlic was effectively inhibited in the all irradiated and low temperature groups until 10 months of storage, while the nonirradiated and 50 Gy groups were partially rooted around the 4th month after storage under both conditions. Weight loss and spoilage were shown to be little affected by irradiation until the nonirradiated garlic sprouted, and at the latter stage of storage period, the optimum dose of irradiation showed a significant effect on the reduction of weight loss and spoilage in stored garlic. It was also found that irradiation for sprout inhibition did not influence the firmness of garlic cloves.
Changes of Polyphenols and Polyphenol Oxidase Active Bands during Apple Wine Fermentation
Chung, Ki-Taek ; Seo, Seung-Kyo ; Song, Hyung-Ik ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 413~417
To examine enzymatic browning of apple wine, changes of active bands of polyphenol oxidase (EC 184.108.40.206) as well as polyphenol substances related to browning of apple wine were investigated during wine brewing. The decrease of total phenol was remarkably inhibited by the addition of sodium metabisulfite. In the meantime, auto-oxidation of catechol in a model system increased proportionally as the reaction pH and temperature increased. Catechol oxidation, however, was not detected at
below pH 5.0. Polyacrylamidegel electrophoretic patterns showed that the apple (Jonathan) indicated 4 bands with polyphenol oxidase activity, designated a, b, c and d whose Rm were 0.21, 0.30, 0.41 and 0.51, respectively. Among these, 2 bands, a and c remained until 5th day fermentation and only c band after 6th day fermentation. After pasteurization of apple wine at
for 30min, c band also remained.
Removal of Malathion Residues from Fruits and Vegetables by Washing Processes
Shim, Aei-Ryun ; Choi, Eon-Ho ; Lee, Su-Rae ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 418~422
In order to determine the removal efficiency of pesticide residues in fruits and vegetables by washing processes, samples of lettuce, young Chinese radish, Chinese cabbage, green red pepper, strawberry and grape were artificially contaminated with malathion and washed according to the household practices. After three times washings with water, the remaining ratios of malathion residues in grape, green red pepper, strawberry, young Chinese radish, lettuce and Chinese cabbage were 9.7%, 25.2%, 28.0%, 29.7%, 38.9% and 57.5%, respectively. After washing with detergent solution followed by two times rinsing with water, the remaining ratios of malathion residues in the same food samples were 1.6%, 8.3%, 15.8%, 24.8%, 27.2% and 45.9%, respectively. The removal efficiency of malathion by detergent washing was significantly higher than the water washings only. The removal ratio of malathion residues was the highest in the first washing and the ratio fell greatly in the following washings. The removal efficiency was not quite different in the temperature range of
of the washing solution, but the efficiency at
was 2-3 times higher than other temperature ranges.
Some Factors Affecting the Viscometric Characteristics of Soymilk
Kim, Woo-Jung ; Kim, Na-Mi ; Kim, Dong-Hee ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 423~428
Changes in viscosity of soymilk were evaluated as affected by solid concentration, temperature, pH and sugar addition. Soybeans were soaked, ground with boiling water, and filtered followed by boiling for 30 min for soymilk preparation. It was found that viscosity increased exponentially as solid concentration increased while the raise of temperature caused exponential decrease in it. A minimum viscosity was ovserved at pH 6.5 in the range of pH 5.0-8.0. The effects of solid concentration and pH on viscosity were reduced as the measuring temperature increased. Addition of sucrose up to 9% showed little effect on viscosity with showing a tendency of increase.
Extrusion Process of Barley Flour for Snack Processing
Mok, Chul-Kyoon ; Pyler, R.E. ; Mcdonald, C.E. ; Nam, Young-Jung ; Min, Byong-Yong ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 429~436
To expand the utility of barley the experiments on the extrusion characteristics of barley flour for snack processing were carried out and the effects of the extrusion conditions on the quality of the extrudates were investigated. The optimum moisture content of barley flour for snack processing was 20%. The moisture content and the density of the extrudates decreased with increasing extrusion temperature and decreasing die size. The die swell ranged from 0.98 to 2.18 according to various extrusion conditions and decreased with increasing temperature above
. The lightness, redness and yellowness increased at higher temperature. The water absorption index and the water solubility index showed their maximum values at
.The gelatinization degree of the extrudates increased with increasing temperature. The fracture fore, Young's modulus and maximum fiber stress decreased, but the deformation to fracture increased, with increasing temperature and decreasing die size. The yield force in puncture test showed lower values at higher temperature. The size and the fraction of the air cells increased with increasing temperature and decreasing die size. The optimum extrusion conditions of barley for snack processing were at the temperature of
, with the die size of 4.5mm when processed at 160 rpm.
Color Changes and Sorption Characteristics of Whole Red Pepper with Relative Humidity and Temperature
Kim, Hyun-Ku ; Park, Mu-Hyun ; Shin, Dong-Hwa ; Min, Byong-Yong ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 437~442
The color changes and sorption characteristics of dried whole red pepper stored at various relative humidity and temperature were studied. Dried whole red pepper was browned at relative humidity above 67%, and was molded at relative humidity above 84%, and was decolorated at relative humidity below 32%. Therefore, about 50% RH condition was suitable for the preservation of dried whole red pepper and the safe moisture content levels for storge to prevent decolorization were ranging from 15.65% to 19.62% dry basis (DB) with varying temperatures. The moisture contents of monolayer value for the dried whole red pepper were ranging from 7.52% to 9.23% (DB) with varying temperatures. The third order regression equation for the equilibrium moisture content prediction with relative humidity was determined.
Effect of Temperature and Salt Concentration on Kimchi Fermentation
Mheen, Tae-Ick ; Kwon, Tai-Wan ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 443~450
Chemical and microbial changes during Kimchi (a group of Korean seasoned pickles) fermentation were carried out at various temperatures and salt concentrations. The time reaching optimum ripening of Kimchi varied depending upon fermentation temperature and salt concentration. At high temperature and low salt content Kimchi fermentation was faster than at low temperature and high salt content. The ratio of volatile to non-volatile acids reached its maximum at the optimum ripening time of Kimchi and decreased thereafter. Leu. mesenteroids, Lac. brevis, Lac. plantarum, Ped. cerevisiae, Str. faecalis and low acid producing Lactobacilli were isolated from Kimchi samples. However, the main microorganism responsible for Kimchi fermentation was Leu. mesenteroides and Lac. plantarum was the main acidifying organism. Total viable count increased rapidly in the beginning of fermentation and reached its maximum number at optimum ripening time and then decreased slowly as the acidity of Kimchi increased. While the total aerobic bacteria and fungi decreased during Kimchi fermentation, the yeast increased significantly at lower temperature.
Thixotropic Properties of Gelatinized Rice Starch Solutions
Kim, Ju-Bong ; Kim, Young-Suk ; Lee, Shin-Young ; Pyun, Yu-Ryang ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 451~456
Rheological properties of gelatinized rice starch solutions were investigated with Brookfield rotational viscometer. The 8% starch solution showed thixotropic behavior with yield stress. The alkali gelatinized starch was more thixotropic than the thermal gelatinized one. The time dependent characteristics of starch solutions followed Tiu's model. The value of rate constant
in Tiu's model increased linearly with shear rate, and was exponentially dependent on concentration and temperature. Temperature dependency of rate constant and apparent viscosity followed Arrhenius type equation and the activation energy were about 14.3 and 6.8 Kcal/g mole, respectively. The
was found to be useful to evaluate changes in structaral decay on the shearing time of gelatinized rice starch solutions.
Cooking Properties of Akibare and Milyang 23 Brown Rice
Kim, Kwang-Joong ; Pyun, Yu-Ryang ; Choi, Hyung-Taeg ; Lee, Sang-Kyu ; Kim, Sung-Kon ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 457~462
Cooking rate calculated from hardness change, and gelatinization aspects observed by X-ray diffraction and scanning electron microscope of brown rice were investigated. Optimum ratio of water to rice of Akibare and Milyang 23 was 1.65 and 1.73, respectively. Milyang 23 was cooked at a faster rate than Akibare. Cooking rate of brown rice was about an half of white rice. The temperature dependence of cooking rate of brown rice was found to be relatively low. The activation energy for cooking were in the range of 15,000 to 16,400 cal/mol at 80 to
and 8,200 to 8,600 cal/mol at 100 to
. The gelatinization degree determined from X-ray diffractometry was approximately consistent with the cooking degree expressed by reciprocal hardness.
Saccharification of Uncooked Starch
Lee, S.Y. ; Shin, Y.C. ; Lee, S.H. ; Park, S.S. ; Kim, H.S. ; Byun, S.M. ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 463~471
For the eventual alcohol production from uncooked starch, an efficient saccharification process was examined by using the combined action of steeping, pectin depolymerase,
and glucoamylase. The total sugar content of rice, sweet potato and tapioka used were 4.53, 4.26, and 3.92 mmole/g sample.
of the total sugar was hydrolyzed when cooked starch was saccharified under the condition which is currently used in industry. The smaller starch particle was used, the more saccharification was obtained. Efficient saccharification was obtained by treatment with 5%
(sample: working volume = 1:2) at
for 12 hr. Optimization was carried out for the saccharification of uncooked starch by the combined action of pectin depolymerase,
, and glucoamylase. The conditions are: pectin depolymerase; pH 4.5,
, 2 hr,
; pH 6.0,
, 1 hr, and glucoamylase; pH 3.5,
, 1 hr. Simultaneous treatment of the combined action of macerating, liquifying and saccharifying enzymes yielded better result than stepwise treatment of 3 enzymes. Degrees of saccharification of uncooked tapioka, rice and sweet potato were 82, 90.5, and 84.5%, respectively on the basis of total sugar, under the optimized conditions.
Changes of Protein During Growth of Soybean Sprout
Yang, Cha-Bum ; Park, Sang-Ki ; Yoon, Suk-Kwon ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 472~474
Gel filtration of water soluble protein of soybean and cotyledon of sprout at various growth stages by using Sephadex G-200 showed 5 fractions (A,B,C,D and E). According to gel filteration and disc gel electrophoresis, fraction B,C and D were identified as 11S,7S and 2S, respectively. Fraction A was turbid substance and fraction E showed 1 peak. During growth of sprout 7S decreased firstly, 2S secondly and 11S lastly in cotyledon. Fraction A increased until 6th day and decreased thereafter while E increased throughout the growth. In axis only two fractions (11S+7S and E) were showed, and 11S+7S fraction was little changed and fraction E increased slightly with the growth.
Penetration of Some Humectants into Shark Muscle
Lee, Jong-Soo ; Koo, Jae-Keun ; Cha, Yong-Jun ; Lee, Eung-Ho ;
Korean Journal of Food Science and Technology, volume 16, issue 4, 1984, Pages 475~481
Estimation of the penetration rate of humectants has been considered to be important in effective control of food processing when intermediate moisture food is manufactured by the moist-infusion method. In this study, when shark (Isurus glaucus) muscle was soaked in four common humectants (sucrose, sorbitol, glycerol, and propylene glycol), the equation of their penetration rate was drawn as a function of time using high performance liquid chromatography analysis. Penetration rates increased with soaking temperatures and decreased inversely with molecular weights of humectants. The penetrated amounts for 10% humectant solution reached about equilibrium after soaking for 10 hours and for 30% humectant after soaking for about 7 hours. In consideration with the penetration rate of the sample soaked in 10% humectant and complex solution of each 10% humectant, little difference was found between them. When the sample was soaked in 10% humectant and 30% humectant, it seemed to be able to apply the following regression equation to estimate the penetrated amounts: M = a log (c.t)+ b where M = penetrated amounts; c = concentration of humectant; t= soaking time; a, b = constant and c.t should be within