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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 23, Issue 6 - Dec 1991
Volume 23, Issue 5 - Oct 1991
Volume 23, Issue 4 - Aug 1991
Volume 23, Issue 3 - Jun 1991
Volume 23, Issue 2 - Apr 1991
Volume 23, Issue 1 - Feb 1991
Selecting the target year
Changes in Physical Properties of Salted Egg Yolks as Affected by Salt Content During Frozen Storage and Their Effects
Kim, Jae-Wook ; Cha, Ga-Seong ; Hong, Ki-Ju ; Choi, Chun-Un ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 389~393
The changes in Physical properties of egg yolk(refractive index 43) as affected by salt content(7%, 10%, 13%) during frozen storage and their effects on functionalities in mayonnaise preparation were investigated. As the frozen storage period of salted egg yolk increased, viscosity was increased, and further increased with higher salt content, and emulsification capacity was gradually decreased. In case of egg folk with 7% salt, emulsification capacity was considerably decreased during the storage at
over 4 months. Microbes of salted egg yolk were decreased with frozen storage, but the difference was not due to salt content. Mayonnaise. Prepared with frozen egg yolks stored for
months, maintained a minimum viscosity. Viscosity became higher in the mayonnaise which prepared with egg yolk of higher salt content stored at
. Oil particle size of mayonnaise with the yolk contained more salt was smaller, when the yolk was stored at
. Noticible microbes were detected in the mayonnaise right after preparation, but not detected in the mayonnaise after 1 month storage.
Purification of Mold Protease Isolated from Katsuobushi
Kim, Kwan-Woo ; Yun, Tai-Uk ; Kim, Jun-Pyong ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 394~399
The strain OK-63 isolated from katsuobushi was cultured on wheat bran medium and the isolate was morphologically identified as an Aspergillus niger group and showed maximum pretense activity and multiplication after 6 days of cultivation. Protease was purified by ammonium sulfate fractionation. Sephadex G-100 gel filtration and DEAE-cellulose column chromatography. The purified enzyme showed single band by polyacrylamide gel electrophoresis and the purity was 150 times higer than crude enzyme. The recovery of enzyme activity was found to be 45%.
Properties of Aspergillus niger Protease Isolated from Katsuobushi
Kim, Kwan-Woo ; Yun, Tai-Uk ; Kim, Jun-Pyong ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 400~404
Protease was purified from Aspergillus niger propagated on katsuobushi. The optimal pH and temperature of the enzyme were 7.2 and
, respectively. The enzyme was stable at
and at below
. Enzyme activity was promoted by
, whereas it was inhibited by
. The acidic, basic and neutral amino acid compositions were found to be 22.63, 13.57 and 63.80%, respectively. The content of nonpolar, poler and sulfur-containing amino acids were 39.72, 20.03 and 9.53% respectively, and aspartic and glutamic acids were abundant. The molecular weight was 42,000 and isoelectric point was estimated pH 5.6.
Antitumor Effect of Polysaccharide Produced from a Mutant of Acetobacter pasteurianus IFO 13751-5
Kim, Dong-Seuk ; Ryu, Beung-Ho ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 405~409
The polysaccharide was predominantly composed of glucose (79.60%), galactose (9.68%), mannose(8.67%), fructose (1.96%;) and xylose (0.09%). Major amino acid in protein was consisted of cystein, aspartic acid, valine and glutamic acid. The tumor growth inhibition ratio of the polysaccharide against Sarcoma 180 was at highest level of 64.96%, when administerd at the concentration of 50 mg/kg and life prologation ratio showed 28.91% at the concentration of 50 mg/kg. The direct cytotoxic effect of polysaccharide was not observed in the tumor bearing mice with Sarcoma 180 in vitro.
Color and Sensory Characteristics of Chicken Patties as Affected by Irradiation and Storage Temperature
Chuang, Ju Tzu ; Yi, Young-Hyoun ; Chen, Tsun Chieh ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 410~413
Prefried chicken patties were irradiated at dose levels of 0, 2, and 4 kGy using
source and stored at
, separately for the evaluation of color and sensory characteristics. Irradiation dose of 4 kGy slightly darkened the internal color of chicken patties. Except for the internal portion of the frozen samples, an increase (p<0.05) in Hunter 'L' values was observed for both the surface and interior of patties during storage. Upon refrigerated storage, Hunter 'a' values, both on the surface and internally, decreased as the storage period progressed. Only storage period affected (p<0.05) the Hunter 'b' values of patty surfaces and interiors. No difference (p<0.05) in odor, taste, color, and texture of the patties was observed for irradiation dose and storage period as evaluated by triangle tests except between 2 kGy and 4 kGy irradiated samples before forzen storage.
Isolation and Characteristic of Polyphenol Oxidase from Jerusalem Artichoke Tuber
Park, Eun-Bae ; Lee, Jun-Sik ; Choi, Eon-Ho ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 414~419
Polyphenol oxidase from Jerusalem artichoke(Helianthus tuberosus L.) tubers was partially purified by precipitation with ammonium sulfate, followed by gel filtration on Sephadex G-100. The enzyme showed maximal activity at pH 6.5 and
. Kinetic studies indicated
value of 3 mM for catechol and activation energy of 72.6 kcal/mole. As for substrate specificity of polyphenol oxidase the enzyme showed high affinity towards diphenol compounds, but not towards monophenols. The enzamatic browning was completely inhibited at 1 mM concentration of L-ascorbic acid, sodium hydrosulfite and L-cystein(HCl). The activity of polyphenol oxidase in 0.1 M potassium phosphate buffer(pH 6.5) was fairly stable for a week at
, while it decreased remarkably at
Changes in Tissue Structure and Pectins of Chinese Cabbage during Salting and Heating
Yoo, Myung-Shik ; Kim, Ju-Bong ; Pyun, Yu-Ryang ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 420~427
The structure of fresh, salted and heated petiole tissue from Chinese cabbage was examined with optical microscope, and the pectin of the tissues was fractionated by successive extraction. The pectin in Chinese cabbage consisted mainly of high methoxyl pectin(pA) and low methoxyl pectin(pB). The pA content was converted to pB markedly by salting and heating at
for 30 min while heating the cabbage above 80 decreased pB content. The firmness of heated tissue was highly correlated with pB content(r=0.996). Cytorrhysis test showed that pore size of the tissue became smaller by salting and heating at temperature below
Effect of NaCl, Phosphate and pH on the Functional Properties of a Mixed System of Pork Myofibrillar and Plasma Proteins
Kim, Cheon-Jei ; Han, Eui-Su ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 428~432
This study was carried out to investigate the effect of NaCl, pH and phosphate on the functional properties of a mixed system of plasma protein and myofibrillar proteins. The solubility of plasma protein, myofibrillar protein and the mixture (plasma+myofibrillar protein) increased according to the increase of NaCl concentration (
) and pH
). The solubility, emulsifying activity and capacity of the mixture were lower than those of plasma protein, whereas higher than those of myofibrillar protein. The gel strength of the mixture and myofibrillar protein showed a significant increase when NaCl concentration was increased from 2 to 3%. The gel strength of myofibrillar protein increased about four times when 0.3% polyphosphate added to the sample containing 2% NaCl, whereas the moisture loss of the mixture and myofibrillar protein decreased significantly. The gel strength of plasma protein, myofibrillar protein and the mixture increased slightly at
protein concentration, whereas the gel strength of those increased significantly as the protein concentration increased from 5 to 9%.
Effect of Naturally Occurring Antioxidants on the Oxidative Stability of Fish Oil
Han, Dae-Seok ; Yi, Ock-Sook ; Shin, Hyun-Kyung ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 433~436
Natural compounds which could improve the oxidative stability of fish oil was screened from spices, herbs and naturally occurring antioxidants. Induction period of fish oil determined from oxidation curve by Rancimat (
) was hardly affected with the addition of water-soluble and lipid-soluble fractions of garlic, leek, sesame leave and orange peel, and of organic acids such as citric acid, EDTA and selenium. Caffeic acid, catechin, quercetin and gallic acid laurylester, however, could extend the induction periods by
times with the addition level of 0.1%(w/w). Rosemary extract and sesamol have a marked effect in retarding oxidation of fish oil. For example, induction periods of the oil samples stabilized with 0.1 rosemary extract and 0.1 sesamol were 16.4 hr and 11.6 hr, respectively, as compared to 4.0 hr of a control. When rosemary extract was used in combination with ascorbic acid (0.02%) or 8-tocopherol (0.2%), induction period could be extended to ca. 28 hr due to the synergism.
Effect of Feeding Rate for Operation Properties of Centrifugal Thin Film Evaporator
Kim, Byeong-Sam ; Park, Noh-Hyun ; Park, Moo-Hyun ; Han, Bong-Ho ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 437~441
During the evaporation of garlic juice by centrifugal thin film evaporator (Centri-Therm, CT-1B), the effect of feeding rate was investigated for its operation properties. On the process condition of feeding rate of 25 to 125 kg/h, theoretical average thickness of the garlic juice film on the rotating cone and residence time of the juice in the evaporator varied in the range of 0.52 to 0.89 mm and 1.77 to 6.75 second, respectively. And the flow of garlic juice was considered as a streamline flow by Reynolds number. At constant temperatures of steam and juice evaporation, concentration ratio decreased with the increase of the feeding rate. But the evapoartion rate and overall heat transfer coefficient increased with the increase of the feeding rate until the feeding rate reached a certain value and then decreased. On the conditions of
, evaporation temperature of
and initial feed concentration of
, concentration ratio and overall heat transfer coefficient were
Isolation and Characterization of Fuji Apple Peroxidase
Jee, Wan-Jung ; Cho, Nam-Sook ; Kim, In-Cheol ; Park, Kwan-Hwa ; Choi, Eon-Ho ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 442~446
Three peroxidase fractions (peak I, II, III) were isolated from Fuji apples using CM-cellulose chromatography. The homogeneity of the isolated peroxidase isozymes was established by isoelectric focusing and electrophoresis. Isoelectric points of the isozymes were 3.80, 3.82, and 3.85, respectively. The optimum pH of peroxidase isozymes were pH 5.0(peak I) or 5.5(peak II, III), and optimum temperature was
when assayed by using guaiacol and
as substrates. Inactivation rate of three peroxidase isozymes were different at temperature of
and at pH of 5.5. The isozyme of peak II was found to be more heat stable than those of peak I and III. D values at
of peroxidase isozymes (peak I, II, III) were estimated to be 660 sec, 1,320 sec, and 600 sec, respectively. The thermal stability of Fuji apple peroxidase was not influenced in the presence of 0.032 M sucrose or lactose. However, the thermal stability of the enzyme was decreased by fructose and glucose.
Rapid Determination of Seed and Stem Content in Red Pepper Powder by Near-Infrared Reflectance Spectroscopic Analysis
Cho, Rae-Kwang ; Sohn, Mi-Ryeong ; Ann, Jae-Jin ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 447~451
Red pepper peels stored with seeds or stems in the powder state at
resulted in decrease of quality components such as capsanthin, capsaicin and total sugars. The effect of seeds on the quality deterioration was larger than stems. A near-infrared reflectance spectroscopic(NIRS) method was evaluated for the determination of seed and stem contents in red pepper peels. The standard error of prediction was 1.76% in seeds and 0.43% in stems. It is concluded that the NIRS method is suitable for the determination of seen and stem contents in red pepper powder.
Characterization of Extracellular Proteolytic Enzyme of Isolated Psychrotrophic Bacteria from Cheddar Cheese
Kim, Eun-Ah ; Lee, Kyung-Wook ; Boo, Won-Back ; Lee, Hyung-Hoan ; Kwak, Hae-Soo ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 452~458
Psychrotrophs producing protease were isolated during ripening periods of Cheddar cheese and one of them containing the highest protease activity was identified as Pseudomonas fluorescens 65. The extracelluar proteolytic enzyme was partially purified from P. fluorescens 65 through the Sephadex G-100 gel filtration. The protease was eluted between 190 ml and 230 ml of elution volume of sodium phosphate buffer. The purified protease showed a single band in SDS-PAGE and its molecular weight was 47,000. The composition of amino acid for the protease was determined and the most abundant amino acids were glutamic acid (14.96%) and serine (13.86%). The optimum temperature and pH for the activity was
and 6.0, respectively.
Changes in Composition of Fish Meat by Thermal Processing at High Temperatures
Oh, Kwang-Soo ; Kim, Jeong-Gyun ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 459~464
The mackerel meat was packed in square No 3B can, and thermally processed at
to reach Fo values of 5, 10 and 15. On heating at
, pH and volatile basic nitrogen content increased markedly, and histamine was detected at concentrations of 3.98 mg/100g in raw meat, 10.45 mg/100g in Fo 5 sample, 7.54 mg/100g in Fo 15 sample, respectively. Total free amino acid content of mackerel meat decreased with increasing Fo values. Little changes were observed in free amino acid composition, but histidine decreased significantly during heat treatment. Degradation of inosine monophosphate was proceeded during preparation and thermal processing of samples, and trimethylamine oxide changed to trimethylamine almost equivalently. In changes of lipid components, peroxide and carbonyl values were increased markedly during heat treatment. When the sample was heated at the Fo values of 5 or higher, content of non-polar lipid(NL) was increased while that of polar lipid(PL) was decreased, and percentages of polyenes such as 22 : 6 decreased with increasing Fo values. The decomposition of polyunsaturated fatty acids in PL were much greater than those in total lipid and NL.
Effect of Palm Oil Blending on the Thermal and Oxidative Stability of Soybean Oil
Han, Yoon-Sook ; Yoon, Jae-Young ; Lee, Su-Rae ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 465~470
In order to investigate the thermal and oxidative stability of different frying oils including soybean oil, palm oil, two blended oils of soybean-palm (5 : 5 and 7 : 3) and shortening, physico-chemical properties such as acid value, peroxide value, TBA value, degree of coloring, refractive index and specific gravity of the frying oils were measured during the preparation of French fried potatoes by repeated frying. The instability of soybean oil against thermal and oxidative degradation could be lessened by using blended oils in which the ratio of palm oil to soybean oil is more than 50%.
Preparation of the Fermented Product by Lactic Acid Bacteria from Cheese whey
Yoo, Eun-Jeong ; Heo, Tae-Ryeon ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 471~477
The optimum conditions for the development of a lactic acid beverage from the concentrated whey were studied using reverse osmosis system. For lactose hydrolysis rate and acid productivity, the strain mixture of Streptococcus thermophilus and Lactobacillus bulgaricus was more efficient than that of Streptococcus cremoris and Streptococcus lactis. The titratable acidity was increased at higher LCR (lactose concentration ratio) of whey. However, the higher LCR of whey was, the slower the pH decreasing rate was. The amount of sediment was maximum at LCR of 1.0 : 1 whey, hit there was no sediment at LCR 3.0 : 1 whey after 12 hours. Propylene glycol alginate was the best stabilizer and prevented from sedimentation at the concentation of less than 0.1%. Aspartame as a sweetener of yoghurt flavor had the best palatability.
Studies on the Change in Rheological Properties of Chungkook-jang
Lee, Boo-Yong ; Kim, Dong-Man ; Kim, Kil-Hwan ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 478~484
As a work on the preparation of spread type product using chungkook-jang, proximate composition and enzyme activity of chungkook-jang were analyzed and extrusion capillary viscometer was made. The effects of moisture content, oil type and content and temperature on the rheological properties of chungkook-jang spread were investigated. As the moisture content of chungkook-jang spread increased from 55% to 65%, apparent viscosity
decreased and spreadibility and L value in Hunter color system increased. On the contrary, as the added oil content of chungkook-jang spread increased from 10% to 30%, rla increased and spreadibility and L value decreased. Specially, in case of palm olefin addition, the rla of chungkook-jang spread was more high than that of soybean oil addition. As the temperature of chungkook-jang spread increased, rla decreased and spreadibility increased. In the same conditions, the
of chungkook-jang spread increased in order of B. natto, B. natto and B. subtilis mixture and B. subtilis fermentation.
Effect of Blanching and Germination of Soybeans on the Quality of Soymilk
Ha, Sang-Do ; Kim, Sung-Soo ; Park, Choul-Soo ; Kim, Byung-Mook ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 485~489
In order to study the effects of blanching and germination of soybean on the quality of soymilk, the soybeans were differently treated as follow; (1) blanched for 5 min at
, (2) germinated for 2 days at
, (3) germinated for 2 days and then blanched for 5 min at
. The qualities of various soymilks prepared from the treated soybeans were compared with those of soymilk from the untreated soybeans. Blanching of soybeans decreased yields, solid materials, viscosity, total protein, soluble nitrogen, and total sugar of soymilk but no effect on its free sugar contents, specific gravity, and pH. The blanching, however, improved the sensory properties and decreased the n-hexanal contents of soymilk to about 1/2.4. Germination of soybeans improved the yields, physical, chemical, and sensory properties and decreased the n-hexanal contents of soymilk to about 1/5. The germination plus blanching of soybeans showed kind of combined effects of germination's and of blanching's, resulting in the decrease of n-hexanal to about 1/10 and improvement in sensory properties of soymilk.
Physical and Organoleptic Characteristics of Kongjaban Prepared under Different Cooking Conditions
Jung, Soo-Jung ; Yoon, Jae-Young ; Lee, Su-Rae ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 490~497
Kongjaban (a Korean-style seasoned black soybean) prepared under various conditions such as different soaking temperatures and time, cooking rate, and amounts of sugar and soy sauce was investigated with respect to its physical and sensory qualities. Soaking soybeans in water at
prior to heating decreased the hardness, degree of browning and saltiness of kongjaban, regardless of soaking temperature. As the cooking time after addition of sugar and soy sauce increased, the degree of browning, saltiness and hardness of kongjaban increased markedly. The amount of sugar and soy sauce did not make a distinct difference in its physical properties whereas its hardness increased slightly with increasing sugar amount. According to the sensory evaluation, the color, hardness and saltiness of kongjaban significantly increased with increasing cooking time. Color, hardness and sweetness increased as the amount of sugar increased whereas the amount of soy sauce did not affect the sensory characteristics except for saltiness.
Relationship Between Hot Water Solubles of Rice and Texture of Cooked Rice
Kim, Kwan ; Kang, Kil-Jin ; Kim, Sung-Kon ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 498~502
The relationships between the textural properties of cooked rice and hot water-solubles of rice or rice flour were studied. The amounts of solubles or soluble amylose among japonica varieties were similar, but those among Tongil type varieties were different. At the same heating conditions, japonica varieties showed higher contents of solubles as well as soluble amylose than Tongil varieties. The solubles and soluble amylose from rice or rice flour showed a negative correlation with hardness but a positive correlation with adhesivess of rice cooked with optimum water.
Production of Glycosyl Sucrose by Cyclodextrin Glycosyltransferase of Alkalophilic Bacillus sp. No.4 and Its Application for Low-Cariogenic Sugar
Sohn, Cheon-Bae ; You, Mi-Kyeong ; Kim, Myung-Hee ; Moon, Suk-Keung ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 503~509
Action of a cyclodextrin glycosyltransferase (CGTase) produced from alkalophilic Bacillus sp. No.4 was studied in a solution containing starch and sucrose to prepare glycosyl sucrose syrup with good sweetness and antidecaying properties of teeth. In the initial stage of the reaction the CGTase produced cyclodextrin, however, the cyclodextrin disappeared and glycosyl sucrose was formed with the lapse of reaction time. The best proportion of sucrose to starch for prodution of glycosyl sucrose was about 1 : 1. The optimum pH and temperature of the coupling reaction was pH 6.0 and
, respectively. Main composition of glycosyl sucrose syrup prepared with 20% starch and 20% sucrose was sucrose 18%, glucosyl sucrose (
) 15.3% and maltosyl sucorse (
) 11.3%. And glucose, maltose and maltotriose were produced very little. Smaller amounts of acid and insoluble glucan were formed in the syrup by Streptococcus mtans OMZ176 than in the sucrose. Therefore, the prepared glycosyl sucrose sucrose syrup is expected to prevent teeth from decaying.
Improvement of Frozen Yeast Dough Stability for Doughnuts by Response Surface Methodology
Lee, Young-Chun ; Kang, Yun-Young ; Lee, Kyung-Hae ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 510~516
To improve the stability of frozen yeast raised dough for doughnuts, amounts of sugar, sodium steroyl lactylate(SSL) and
to be added to the premix were optimized, using the fractional factorial design with 3 variables and 3 levels, by a RSM computer program. The optimum sugar, SSL and
levels to be added to the premix were 2%, 0.3% and 25 ppm for a desired doughnut volume, and 2%, 0.4% and 10 ppm for a desired doughnut texture, and 2%, 0.4% and 20 ppm, respectively, for an overall optimum quality of doughnuts. The frozen stored yeast raised dough prepared without floor time resulted in better doughnut volume and texture than that with floor time. The yeast raised dough prepared with the formula for overall optimum quality, was formed to ‘plain ring’ type doughnuts and stored at
for 5 weeks. Volume and texture of fried doughnuts were comparable to those of control for 2 weeks of storage, and then deteriorated noticeablly from 3 weeks of storage.
Could Glucose Oxidase and Superoxide Dismutase Inhibit the Oxidation of Fats and Oils ?
Han, Dae-Seok ; Yi, Ock-Sook ; Ahn, Byung-Hak ; Shin, Hyun-Kyung ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 517~519
The effect of glucose oxidase (GO) and superoxide dismutase (SOD) on the oxidative stability of fish oil was investigated from oxygen content and peroxide value determinations of oil samples stored in vial. GO could inhibit the oxidation of the oil by removing headspace oxygen. When SOD was solubilized in the oil, peroxide value was slightly lower than that of a control, indicating that the enzyme also had an effect on retarding the oxidation.
D(-)- and L(+)-Lactic Acids Contents of Commercial Yogurts
Park, In-Duck ; Hong, Youn-Ho ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 520~522
The ranges of D(-)- and L(+)-lactic acids contents in commercial liquid yogurt were
, respectively. The ratio of L(+)-lactic acid to D(-)-lactic acid was
. The ranges of D(-)- and L(+)-lactic acids contents in commercial semi-solid yogurt were
respectively. The ratio of L(+)-lactic acid to D(-)-lactic acid was
Stimulatory Effect of Oxygen on the Browning of a Soy Sauce Model System
Park, Seung-Kyu ; Kyung, Kyu-Hang ;
Korean Journal of Food Science and Technology, volume 23, issue 4, 1991, Pages 523~525
The stimulatory effect of oxygen on the browning of a soy sauce model system (glucose-glycine in 18% NaCl solution) with or without added organic acids were investigated. The group incubated aerobically browned at a significantly higher degree than the group incubated anaerobically. Organic acids also positively affected the browning of the soy sauce model system.