• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.838-844
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• 1989

The physicochemical and organoleptic properties of Korean pickled cucumbers were studies for their changes during fermentation. The Korean pickled cucumbers were prepared by salting in 5-15% NaCl solution and fermented for 7-10 days. The results showed that the increase of salt concentration in cucumber had a linear relationship with logarithmic value of brining time. The higher NaCl concentration in salt solution resulted a rapid salt penetration into cucumber while the rate of changes in pH, the total acidity and turbidity were reduced. The color of cucumber surface were changed from green to yellow-green color as the fermentation progressed. The hardness of cucumber decreased repidly after one day of fermentation, followed by a little decreased until it reached to pH 3.2. A little increase in pH and decrease in total acidity were measured thereafter. The evaluation of sensory quality showed that the acidic and fresh cucumber-like-flayer decreased and yeast-moldy increased as the fermentation progressed. The sensory changes were more evident for lower salt concentration of NaCl solution. The softness of cucumber became to be significant from 4th day of fermentation in 5% salt solution.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.845-850
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• 1989

Effect of high temperature soaking in salt solution and short time microwave heat treatment on quality of Korean pickled cucumbers during fermentation was investigated. The Korean pickled cucumbers were fermented at $25^{\circ}C$ for 10 days in 10% salt solution. The physicochemical properties measured were pH, the total acidity, hardness and the sensory properties of odor, taste and texture were also evaluated. The result showed that the effect of soaking cucumber in $80-90^{\circ}C$ hot salt solution significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was found for those soaked in $60-70^{\circ}C$. The effect of microwave treatment inhenced fermentation a little for short treatment but it was significantly reduced softening rate of texture by 3 minutes heating. The sensory evaluation of Korean pickled cucumber was found that heat treatments with hot solution and microwave heating had a possitive effect for reduction of softening of cucumber tissue, however odor and taste were not significantly affected.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.238-244
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• 1983

The cooking quality of irradiated chestnut after longterm storage were evaluated. 1. Color degree and tannin content of irradiated chestnut were slightly increased with the storage, but there was a little difference according to the radiation dose after nine months storage. 2. The main component of free sugars in the irradiated chestnut were identified as sucrose, glucose, fructose and the amino acids of chestnut were identified in the decreasing order of glutamic acid, aspartic acid, leucine, arginine, glycine, alanine, serine, pheylalanine, threonine, valine, isoleucine, tyrosine, methionine and cystein. Free sugars and amino acids of 25 Krad irradiated group showed a little difference compared with those of control group after nine months storage. 3. The calorie of candied chestnut prepared from nine months stored was marked 199 Kcal/100g of edible parts compared with 159 Kcal of raw chestnut. 4. Texture and sensory evaluation of candied chestnut prepared from nine months stored were better in 20-25 Krad irradiated group than in control group.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.231-237
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• 1983

In order to develop the commercial storage method of chestnut by irradiation combined with natural low temperature, a chestnut variety Ok-gwang was stored in a natural low temperature storage room ($450{\times}650{\times}250$ cmH; year-round temperature change, $2-17^{\circ}C$; R.H., 80-85%) on batch scale followed by irradiation with optimum dose level. Sprouting rate of chestnut was 100% after seven month storage in control whereas that of 20-25 Krad irradiated group was only 5-15%. In comparison of rotting rate, weight loss and texture, 25 Krad irradiated group was better than that of control. Moisture and reducing sugar were increased in contrast with the decrease of total sugar during nine month storage and these changes were more remarkable in control. Ascorbic acid content was slightly decreased both in control and irradiated group; more decrement was noticed in control.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.55-60
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• 1986

The effects of temperature (70-$100^{\circ}C$), pH (3-8) and various sugars were investigated on the reaction rate, activation energy and z-value of Maillard reaction of 0.8m sugar and 0.8m glycine mixture. The sugars compared were glucose, fructose, lactose and sucrose, and the reaction was evaluated by absorbances at 278nm for pyrazine compounds and at 400nm for brown pigments. Fructose-glycine mixture showed a faster initial reaction rate than that of glucose-glycine, which was reversed by the order of glucose > fructose > lactose > sucrose after 10 hrs of reaction at pH 5.8 and $100^{\circ}C$. Generally, higher activation energy was required for forming pyrazines than that of brown pigment development. The highest z-value was obtained for lactose-glycine mixture, followed by glucose or fructose-glycine which had almost same z-value. The reaction rate was little affected by the pH change in the range of 4-6, while pH < 3 and pH 6-8 caused a significant increase in the rates.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.865-870
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• 1990

Four different fermentation methods of Korean cucumber pickles were compared with conventional method, pickling in 10% NaCl solution at $25^{\circ}C$, in order to improve the storage stability. The methods studied were brining the cucumbers in hot($90^{\circ}C$) 10% NaCl solution(method A), addition of KCl and $CaCl_2$ into the hot salt solution(method B) addition of a sodium salts mixture of phosphates, nitrite and citrate into half fermented pickles prepared by method B(method C), substituted nitrite and citrate with KCl in method C(method D). It was found from results that the method C and D reduced the decreasing rate of pH very significantly by more than 3 fold and method B also showed the reducing effect. However, higher total acidity was measured for method C and D, which was opposite to pH results. Changes in hardness of cucumber showed little difference to control while color of brining solution exhibited some difference in their Hunter values. Organoleptic comparison showed a clear effect of salts mixtures by receiving the significant higher scores in fresh cucumber flavor and lower values in yeast moldy and sour flavor for method C and D when those were compared to control.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.802-807
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• 2001

Effects of ${\beta}-glucan$ from Lentinus edodes and hordeum vulgare on blood glucose and lipid composition were investigated. Diabetes mellitus was induced in male ICR mice by the injection of alloxan into the tail vein at a dose of 75 mg/kg. The ${\beta}-glucan$ were administered orally for 10 days and the normal and alloxan-control group were orally administered with saline. The body weight gain and food intake were monitored every day and plasma levels of glucose, triglyceride, total cholesterol, LDL-cholesterol were determined at last day. Also the weight of liver, heart, spleen and kidney were determined. The ${\beta}-glucan$ from Lentinus edodes and hordeum vulgure lowered significantly body weight gain in alloxan-induced diatetic mice (p<0.05) and plasma glucose levels compared to that of alloxan-control group. Plasma triglyceride level in B500 was lowered in alloxan-induced diabetic mice. The ${\beta}-glucan$ of hordeum vulgare lowered weight of liver significantly (p<0.05). In conclusion, it was assumed that ${\beta}-glucan$ from hordeum vulgare have anti-hyperglycemic and anti-obese effects by reducing body weight gain and decreasing serum glucose and triglyceride level.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.300-306
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• 1989

Physico-chemical changes caused by salting Korean radish cubes (for Kakdugi) with sodium chloride solution were investigated. Two-centimter cubes of Korean radish were soaked in saline solution of 5, 10, 15, 20 and 25 percent concentration. Optimum salinity, 3% as determined by taste, was reached in six hours at 5% strength, two hours in 10%, one hour at 15% and within one hour at concentration of 15% plus. Radish cubes salted in 5, 10. 15, 20 and 25% sodium chloride solution in a cube/solution weight ratio of 1:1 decreased in volume from 7.6 to 11.2% after one hour, and from 11.2 to 17.9% after six hours. Decrease in moisture content was from 83.0 to 75.9% in one hour and from 74.5 to 68.5% after six hours. $Potassium\;ion(K^+)$, $calcium\;ion(Ca^{2+})$ and $magnesium\;ion(Mg^{2+})$ content was significantly decreased by salting, but $sodium\;ion(Na^+)$ content greatly increased. In addition, salting caused firmness of the cubes to decrease, and cell shapes to shrink by plasmolysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.86-96
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• 1984

In order to provide basic data for food processors and to improve eating habits and healthy diets, four primary tastes and hot taste threshold of Koreans, physio-chemical properties of foods and food preference were investigated. The results of this study were as follows; 1. The recognition threshold concentration of four primary tastes was 0.016 % of salt, 0.245${\sim}$0.249 % of sweet, 0.004${\sim}$0.008 % of sour and 0.008${\sim}$0.012 % of bitter. Threshold concentration of hot taste was 170,000${\sim}$600,000 Scoville Heat Unit(S.H.U.) 2. The most acceptable tastes were 0.3 % saltiness in 0.375 % broth(at $60^{\circ}C$), 6 % sweetness in 2 % instant coffee(at $60^{\circ}C$) and 19.3 sugar-acid ratio(16.8 brix/0.8736 % citric acid) in 100 % valencia orange juice(at $20^{\circ}C$). 3. The salt concentrations of soup were 1.127 % in average. S. H. U. (scale of hot taste) of soybean sprout soup and spinach bean paste soup ranged between 12,500 and 47,500 equivalent to oleoresin capsicum content of 1.990${\sim}$5.911 (mg %). 4. 'Jigae' (Korean style stew) was the most favorable food and it was revealed that the father influences the formation of his children's eating habits.

• Korean Journal of Agricultural Science
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• v.27 no.1
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• pp.54-62
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• 2000

This study was performed to evaluate the food technological properties according to different emulsion state of carthamus red pigment. For making emulsion, lecithin was used as an emulsifier and polyglycerol monooleate(PGMO) and polyoxyethylene sorbitan monooleate(Tween 80) were used as an assistant, and glycerin, distilled water and soybean oil were used as base materials respectively. Paprika stock solution was used for comparing carthamin on the rheological properties. The results were described as following: 1. Hunter L-value was not drastically increased until passed by 8 hours for glycerin, carthamin, and lecithin mixed sample. 2. Hunter a-value was higher at carthamin added sample than others. and b-value was higher to paprika added sample than others. 3. The viscosity, shear rate and shear stress levels in which glycerin was used as base material were higher than soybean oil or distilled water. 4. In which soybean oil was used as base material. lecithin was not affected on the rheological properties. But, in which glycerin was used. the lecithin was higher affected on carthamin than paprika. 5. The value of shear stress was increased both carthamin and soybean oil. However, that of shear rate was shown similar trends.