• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.289-293
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• 1989

During soaking of soybeans in water at $4^{\circ}C{\sim}98^{\circ}C$, the volume gain of soybeans held a linear relation with the square root of soaking time regardless of soaking temperatures and showed a highly positive correlation with weight gain, which indicated that the volume increase of soybeans was basically due to the diffusion of water. The activation energies for the volume increase were changed at $40^{\circ}C$. The log time to reach a fixed moisture content showed a linear relation with the soaking temperature during soaking of soybeans at $4^{\circ}C-60^{\circ}C$. The z-value to reach 50% hydration was $50^{\circ}C-55^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.527-532
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• 1997

The comparative effects of gamma irradiation and ozone treatment on the microbial inactivation and fatty acid composition were investigated for improving hygienic quality of aloe and pollen powders. Gamma irradiation at 10 kGy resulted in sterilizing total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of aloe and pollen powders. The compositions of fatty acid were not significantly changed by gamma irradiation up to 10 kGy. However, ozone treatment markedly decreased unsaturated fatty acids by approximately $20{\sim}80%$ in contents, whereas it significantly increased saturated fatty acids (p<0.05).

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.446-450
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• 1987

To re-evaluate the browning reactions of fermented soybean products, soy sauce mash with added glucose and/or tyrosine was fermented for 152 days in the presence or absence of oxygen. Glucose negatively affected brown pigmentation either singly or with tyrosine. Tyrosine-added soy sauce mash initially browned at the same rate as the control mash until 127th day and then the former continued to brown at the same steady rate while the control mash stopped further browning. Aerobically incubated mash browned much more than anaerobically incubated one when the browning was compared on the 152nd day of fermentation. More than half of the mash browning was found to be due to the oxygen-related browning during the limited 152 days of fermentation time. Both oxygen-related and oxygen-unrelated browning reactions were found to contribute to the browning of soy sauce mash. Oxygen-related browning, however, was found to be more important than the Maillard browning reaction.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.256-262
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• 1988

During soaking of 4 varieties of Korean soybeans in water at $4-98^{\circ}C$, an equilibrium state was reached after 3 hr at $60-98^{\circ}C$ but no equilibrium state was observed at $4-40^{\circ}C$ during soaking for 10 hrs. The moisture gain of soybeans held a linear relation with the square root of soaking time regardless of soaking temperatures, which indicated that the basic mechanism of water absorption was diffusion of water. The log time to reach a fixed moisture content showed a linear relation with the soaking temperature during soaking of soybeans at $4-60^{\circ}C$. The z-value decreased in proportions to the increase of hydration. The z-value to reach 50% hydration was the same in all soybeans.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.691-696
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• 1989

It Is a unique dietary culture in Korea in that starch is isolated and utilized from steeped potato. In this experiment the potato was steeped in water at $30^{\circ}C$ for 7 days and the properties of starch were examined. The pH in steep water decreased, while sugar cotent (total and reducing) increased. The lager granules were diminished during steeping. Holes on the starch granules were observed from the second days of steeping The density, amylose content, phosphorus and lipid content were decreased. Relative crystallinity of starch reached the highest value at 4th day of steeping and decreased thereafter. The changes in enthalpy of gelatinization were similar. Starch was resistant to acid or enzymatic hydrolysis and showed lower values for swelling power and amylograph viscosities.

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.54-60
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• 1987

Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) were tested for their effectiveness in inhibiting the growth of microorganisms. Among the test microorganisms, the growth of three yeasts (Saccharomyces cerevisiae, Kloeckera apiculata, Cryptococcus hungaricus), three bacteria (Bacillus subtilu, Lactobacillus cases, Escherichia colt) and two molds (Aspergillus oryzae. Penicillium sp.) was progressively decreased as concentrations of BHA were increased. A. oyzae was completely inhibited with 100ppm of BHA and a majority of the test microorganisms (S. cerevisiae, K. apiculata. C. hungaricus, B. subtilis, A. oryzae) were completely inhibited by 150 ppm of BHA. The growths of L. casei, E. coli and Penicillium sp. were not affected as much as those of other microorganisms by BHA. Final cell yiedls were becoming lower as the concentration of BHA increased. The growth of C. hungaricus and L. casci was slightly inhibited by BHT. Other microorganisms were not effected by the test concentrations of BHT.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.382-386
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• 1987

Changes of proteins of whole soybean and soy flour stored under different conditions of humidity (RH 65% and 85%) and packing material (HDPE and OPP/Al/PE film) for 90 days and their influence on formation of soybean curd were investigated. The water holding capacity, total nitrogen, soluble nitrogen, pH and Amylograph viscosity of whole soybean and soy flour were rapidly decreased during storage at high relative humidity. Furthermore, such quality changes were accompanied by considerable differences in final quality of soybean curds; lower volumes of soybean curds. Under the conditions of HDPE and OPP/Al/PE film packing, smaller changes were observed in protein qualify than those without packing.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.290-294
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• 1987

The chemical composition of pearled, cutted and pressed barleys showed that there were no significant differences in calorie and proximate composition between pearled and pressed barley. Cutted barley had lower contents in protein, fat and ash but the same calorie value compared with other barleys. The average ratios of calcium to phophorus and essential amino acid to total nitrogen were 0.143 and 1.66, respectively. The amino acid score was the highest in cutted barley followed by pressed barley. The first limiting amino acid for pearled and cutted barley was lysine. while that for pressed barley being threonine. The major fatty acids were linoleic, palmitic and oleic acids, which comprised of about 92% of the total fatty acids. The ratio of polyunsaturated to saturated fatty acid was lower in pressed barley.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1068-1072
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• 2000

Strawberry jams were prepared with addition of 1.0 and 2.0% dietary fiber isolated from ascidian (Halocynthia roretzi) tunic for recycling wastes of seafood source and developing new food products. The texture of the jams examined were using a back extrusion rig. All of the rheological parameters decreased in the fiber-enhanced jams. Viscosity profiles were also decreased in the fiber-enhanced jam samples. Hunter L' and a' values increased in the fiber-enhanced jams, accordingly revealing reddish color. As a result of sensory evaluations, the result of taste tests and overall acceptability were significantly acceptable. In the list of acceptability factors, except spreadibility, jam where 1% fiber was added, high sensory scores and preferable acceptability were noted.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.319-321
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• 1984

Black pepper powder was irradiated at dose of 3,6 and 9 kGy, stored at ambient temperature in order to investigate the effect of irradiation on their microbial sterilization and physicochemical properties. Total and coliform bacteria were sterilized by irradiation up to 9 kGy and 3 kGy, respectively, and they were not grown until the end of storage period. $D_{10}$ value of total bacteria were in the range of 1.39-1.49 kGy. Proximate composition was not significantly changed according to the increase of irradiation dose except slight increase of the reducing sugar. The yield of volatile oil was slightly decreased by the increase of irradiation dose.