• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.7-15
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• 2004

This research was designed to investigate the antioxidant activity of red cabbage (Brassica oleracea L., BO) fractions on the liposomes consisted of L-$\alpha$-dilinoleoylphosphatidylcholine (DLPC-liposome) and the tyrosinase activity of BO fractions. The methanol extract of BO (BOM) was fractionated into five different partition layers: hexane (BOMH), ethylether (BOMEE), ethylacetate (BOMEA), butanol (BOMB) and aqueous (BOMA) layers. The antioxidant activities of BOM fractions toward oxidized DLPC-liposome were examined by spectrophotometry measuring oxidized conjugated dines. The antioxidant activities of BOMEE and BOMEA fractions toward oxidized DLPC-liposomes were similar to the antioxidant activities of $\alpha$-tocopherol and weaker than that of BHT. The synergy effects of antioxidation of BOMEE and BOMEA fractions added with vitamin C and $\alpha$-tocopherol had even stronger antioxidant activities than the fractions without vitamin C and $\alpha$-tocopherol. These results showed that the fractions of BOMEE and BOMEA could be developed as a potent antioxidant. Out of five different partition layers of BOM fractions, BOMEA exhibited the strongest tyrosinase activity of 94% at a concentration of 40 $\mu\textrm{g}$/mL. This result suggests BOMEA fractions inhibit the foramation of melanin and therefore can be used as the inhibitor of melanin synthesis. Results of antioxidant activity and tyrosinase inhibition indicate that useful bioactive substances exist in BOMEE and BOMEA fractions. Both fractions from BO (red cabbage) have the potential of being developed into health related products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.723-729
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• 2004

To develop foods using dried persimmon, hot-water extracts of dried persimmons were added into strong wheat flour in the ratio of 10, 20, 30, and 40% and the quality characteristics of baked products were investigated. The proximate compositions of dried persimmons hot-water extracts were 70.37% of moisture, 1.72% of crude protein, 0.18% of crude lipids, 1.99% of crude ash and 4.37% of crude fiber, respectively. With increasing the addition of dried persimmons hot-water extracts, moisture content of the added breads was increased to 47.20% from 41.12% of non-added bread and water activity to 0.576 from 0.495. Water binding capacity of the added dried persimmons hot-water extracts rasied weight of the bread but decreased specific volume. In the hunter's color values the more dried persimmons hot-water extracts was added, the lower L vaules we, and the higher a and b values we. In the texture property, the addition of dried persimmons hot-water extracts increased hardness, gumminess and chewiness, while decreased adhesiveness and fracturability. Judging from texture, taste and overall acceptability of the product, recommended substitution level for hot-water extracts of dried persimmons in bread was 30% or less.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.76-82
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• 2009

Wheat is the most widely cultivated cereal and an important source of dietary protein worldwide. Wheat allergy, defined as an adverse immunologic reaction to wheat, encompasses a broad spectrum of disorders with different pathomechanisms and clinical manifestation. The Nuruk, a traditional Korean Koji for brewing, was made with wheat flour and fermenting microbes such as bacteria, yeast and mold. The strains grown on Nuruk secrete various enzymes as amylase and protease. By the activation of such enzymes, starch and proteins in Nuruk are hydrolyzed to sugar and amino acid. Therefore, it is supposed to reduce allergic proteins in wheat. To study quality properties and degradation degree of allergenicity in Nuruk by fermentation, we investigated the changes of general ingredients and allergenicity in Nuruk during fermentation. Moisture contents was decreased from 24.2% to 13.6% during fermentation. Crude lipid and protein contents were gradually increased during fermentation. After 15 days of fermentation, reducing sugar and total sugar contents were reached its maximum level, and they were 27.45% and 39.00%, respectively. Acid and neutral protease activity were significantly increased during fermentation, but alkaline protease activity was not detected. ${\alpha}$-amylase activity was gradually increased and showed maximum level about 2,833.00 U/g after 15 days of fermentation. Glucoamylase activity was the highest level about 497.9 U/g after 10 days of fermentation. The increase of these proteolytic and saccharogenic enzyme activities will provide efficient condition for production of rice wine. Also, protein fractions were isolated from Nuruk, and degradation of these proteins during fermentation were confirmed by SDS-PAGE. IgE immunoblotting using patient's sera with wheat allergy was performed to confirm allergenic protein in Nuruk. These results as fermentation of Nuruk will provide a useful tool for developing safer wheat products to prevent wheat allergy.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.264-271
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• 1999

This study was conducted to know the storage stability of Yackwa, a traditional Korean fried cookie, prepared by two different cooking methods; deep fat frying at 160$^{\circ}C$ for 8 min (DFF), and preheating Yackwa dough and then deep fat frying at 180$^{\circ}C$ for 2 min (MW/DFF). Soybean oil (SBO), hydrogenated soybean oil (HSBO) or hydrogenated palm oil (HPO) were used for frying Yackwa. Compared to Yackwa prepared by DFF, all MW/DFF Yackwa samples had low fat content and high moisture content. MW/DFF saved frying time 6 min compared with DFF. Non-hydrogenated soybean oil for frying fats was replaced with hydrogenated types of soybean oil and palm oil to improve the storage stability of Yackwa. To investigate the oxidation stability of Yackwa during the accelerated storage for 15 days at 60$^{\circ}C$, acid value, anisidine value, peroxide value and oxidation value of Yackwas were measured. Acid values of Yackwa made by MW/DFF were higher than those made by DFF through the whole storage periods, regardless of frying fats. Peroxide and anisidine values of Yackwa coated with syrup were much lower than those without syrup. MW/DFF cooking method, using hydrogenated soybean oil or hydrogenated palm oil for frying, showed lowering effects on peroxide value as well as anisidine value, resulting in improved oxidation stability of Yackwa during the storage. In sensory evaluation, the acceptability of MW/DFF Yackwa was higher than those of the commerical products. Yackwa prepared by MW/DFF cooking method using hydrogenated palm oil, showed the highest acceptability in color, taste and texture among the samples.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.482-490
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• 2017

This study was carried out to analyze the pasting and antioxidant characteristics of cooked mixed grains consisting of germinated millet and rice with varying addition rates and cooking methods. In this study, we chose two foxtail millets: glutinous ('Samdachal') and non-glutinous ('Samdame'), along with a glutinous proso millet ('Ibaekchal'). Cooked mixed grain rice-added germinated millet was cooked by general and high pressure cooking methods, with and without fermented alcohol. The peak and trough viscosity of germinated millet were decreased significantly with increasing amounts of germinated millet. The phenolic compounds and radical scavenging activity of cooked rice-added germinated millet increased significantly with the addition of germinated millet (p<0.05). The total polyphenol contents of cooked rice-added germinated Samdachal, Samdame, and Ibaekchal were 127.74~194.11, 128.20~192.56, and $128.88{\sim}171.28{\mu}g\;GAE/g$, respectively. The total flavonoid contents were 13.79~30.23, 14.77~25.99, and $15.28{\sim}29.56{\mu}g\;CE/g$, respectively. DPPH and ABTS radical scavenging activities were 3.31~5.73 and 6.31~9.69 mg TE/100 g for cooked rice-added germinated Samdachal; 3.14~8.58 and 6.05~10.19 mg TE/100 g for Samdame; and 3.37~7.45 and 6.27~9.27 mg TE/100 g for Ibaekchal, respectively. In this study, phenolic compounds and radical scavenging activity of cooked mixed grain rice-added germinated millet with different addition rates and cooking methods can be used as basic data for manufacturing processed products.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.577-583
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• 2000

The purpose of this study was to investigate the effectiveness of various quality preservative treatments for extending shelf life and maintaining good quality of minimally processed fruit and vegetables produced in Korea. To determine the suitable treatments for delaying quality deterioration, fresh Asian pears and Chinese cabbages were sliced and treated with various quality preservatives (1% CaCl$_2$, 1% NaCl, 3% sucrose, 1% Ca-lactate, 1% vitamin C, 0.05% chitosan ＋1% vitamin C, 0.1% Sporix＋1% vitamin C, hot water (60$\^{C}$), 0.2% L-cysteine), packed with polyethylene film (60㎛-thick), and stored at 4$\^{C}$/0$\^{C}$ or 20$\^{C}$. Various biological and sensory tests were performed to evaluate the quality changes in minimally processed products. Results indicated that Chinese cabbages treated with 1% CaCl$_2$ at 4, and 1% CaCl$_2$ and 1% NaCl at 20$\^{C}$ were most effective in maintaining the quality and minimizing the biochemical changes during storage. For sliced Asian pears, 0.2% L-cysteine and 1% NaCl treatments were effective to reduce browning, and 1% CaCl$_2$ treatment was the most effective to prevent softening during storage at 20$\^{C}$ and 0$\^{C}$. Modified atmosphere packaging of Pleurotus ostreatus and Lentinus edodes had a significantly different shelf life depending on packaging material, packaging thickness and storage temperature. Sealed packaging with polyethylene film (60㎛-thick) for two kinds of mushrooms maintained a good quality with an extended shelf life by 30-50% at 20$\^{C}$ and by 30-130% at 0$\^{C}$. To minimize the quality deterioration which appeared in the condition of polyethylene film packaging, quality preservatives such as KMnO$_4$ and KHSO$_2$＋K$_2$S$_2$O$\_$5/ for SO$_2$ generation were added inside of mushroom packaging. The best condition for maintaining good quality longer was packaging with polyethylene film+SO$_2$ which showed 5080% extended shelf life for both Pleurotus ostreatus and Lentinus edodes at 20$\^{C}$ and 0$\^{C}$.

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.529-536
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• 2004

In this study, the author examined the fermentative abilities and baking properties of commercial baker's yeasts and suggested the fundamental data for the development of the yeast products industry. Carbon dioxide production, expansion abilities of doughs, and maltose fermentative abilities were measured with commercial yeasts. The fermentative abilities of various bread doughs were determined in comparison to a reference yeast and a selected yeast from commercial yeast. Various breads were prepared by these two yeasts and their sensory properties were evaluated. Y7, followed by Y5 and Y4, showed higher ability than any other commercial yeasts in the gassing power of the dough, as measured by a Meissle fermenter. In the expansion abilities of the doughs made from various yeasts by M-Cylinder, Y7, followed by Y4 and Y5, showed the best expansion ability the results were similar to those for gassing power. Therefore, Y7 was selected. The maltose fermentative abilities of various yeasts in Atkin's liquid medium showed a higher value in Y5, Y7 and Y 4. Selected yeast Y7 and the reference yeast K were used for determining the fermentative abilities of various bread doughs. For the various breads prepared by K and Y7, the qualities of the breads such as volume, weight and specific volume were measured. The volume by Y7 was higher in the straight dough bread, and that by K was higher in the sponge dough bread. In the sweet dough bread, both Y7 and K were excellent groups for it. Sensory properties of various breads made from K scored high on the items such as external properties and color in the straight dough bread. It also acquired a good score on the item of the crusts in the sweet dough bread. The overall acceptability of Y7 and K were similar.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.357-370
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• 1982

Recent concern regarding price and availability of fossil fuels has spurred the interest in alternative sources for farm crop drying. Among the available options such as biomass energy, wind power, nuclear energy and solar energy etc., the increasing attention is being directed to the utilization of heat from solar energy especially for farm crop drying. Even though solar energy is dispersed over a large land area and only a relatively small amount of energy can be simply collected, the advantages of solar energy is that the energy is free, non-polluting. The study reported here was designed to help supply the informations for the development of simple and relatively inexpensive solar warehouse for farm crop drying and storage. Specifically, the objectives of this study were to determine the performance of the solar collector fabricated, to compare solar supplemented heat drying with natural air drying and to develop a simulation model of temperature in stored grain, which can be used to study the effects due to changes in ambient air temperature. For those above objectives, solar collector was fabricated from available materials. Corrugated steel galvanized sheet, painted flat black, was used as absorbers and clear 0.2mm polyethylene sheet was the cover material. The warehouse for rough rice drying and storage was constructed with concrete block, and the solar collector was used as the roof of warehouse instead of original roofing system of it. The results obtained in this study were as follows: 1. The thermal efficiency of the solar collector was average 26 percent and the overall heat transfer coefficient of the collector was approximately $25kJ/hr.m^2\;^{\circ}K$. 2. Solar heated air was sufficient to dry one cubic meter of rough rice from 23.5 to 15.0 percent in 7 days and natural air was able to dry the same amount of rough rice from 20.0 to 5 percent in l2 days. 3. Drying with solar heat reduced the required drying time to dry the same amount of rough rice into a half compared to natural air drying, but overdrying problems of the bottom layer were so severe that these problems should be thoroughly analyzed. 4. Simulation model of temperature in stored grain was developed and the results of predicted temperature agreed well with test results. 5. Based on those simulated temperature, changes in the grain-temperature were a large at the points of the wallside and the damage of the grain would be severe at the contact area of wall.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.875-880
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• 2012

This study was conducted to investigate the level of contamination of pathogenic Escherichia (E.) coli in 50 types of red pepper powders collected domestically. Pathogenic E. coli was confirmed using real-time PCR to confirm the 4 types of EAEC, EPEC, EHEC and ETEC. One sample out of 50 was contaminated with pathogenic E. coli. The type of pathogenic E. coli detected in the sample was EAEC. This study was also conducted to determine the effect of alcohol treatment on the reduction of E. coli populations in red pepper powder. The amount of E. coli in the control was $1.2{\times}10^6$ cfu/mL. The amount of E. coli in 10 minutes immersion treatment with 10% alcohol was $1.1{\times}10^6$ cfu/mL. In samples treated with over 20% alcohol, E. coli was not detected. This showed that 10 minutes of immersion in over 20% alcohol might be effective to reduce E. coli. This study was also conducted to determine the effect of UV irradiation on E. coli reduction. The number of E. coli in the control group was $5.0{\times}10^5$ cfu/mL. However, the number of E. coli in 45 min of the UV irradiated sample decreased to $1.0{\times}10^3$ cfu/mL, by $10^2$ cfu/mL. In contrast, E. coli was not detected in an over 60 min UV irradiated sample in $10^{-2}dilution$. This study showed that over 20% alcohol treatment and UV irradiation for 60 min was effective to control E. coli in red pepper powder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.629-635
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• 2002

This study was performed to develop low-fat comminuted sausages (LFSs, < 3%) manufactured with 1% single (Konjac flour, KF; kappa-carrageenan, k-CN and Locust bean gum, LBG) or mixed hydrocolloids and to select the best combination which had similar textural characteristics to those with regular-fat (~25% fat) control. In experiment 1, LFSs were formulated with each 1% hydrocolloid, smoked and cooked to an internal temperature of 71.7$^{\circ}C$. The pH range of LFSs was 6.29 to 6.34 and approximately 23~24% of fat was removed in the final products, resulting in the higher moisture and protein contents (%) in LFSs, as compared to regular-fat control. No differences (p>0.05) in cooking loss (CL, %), expressible moisture (EM, %), and hunter color values (L, a, b) were observed with the addition of each 1% hydrocolloid. However, LFSs containing 1% k-CN had textural hardness values similar to those with low-/regular-fat controls, whereas LFSs having either KF or LBG had similar cohesiveness values to those with regular-fat counterpart. Tn experiment 2, two or three mixed hydrocolloids were added to the low-fat sausage formulation. The addition of mixed KF+LBG (KLL) and KF+CN+LBG(KCL) reduced EM and textural hardness values, as compared to low-fat control. Among the treatments, LFSs containing two or three combinations of CN with KF or/and LBG had similar textural characteristics to those with regular-fat control. These results suggested that multiple addition of CN with other hydrocolloids (KF or LBG) for the replacement of fats in LFSs would be recommended for the proper functional and textural properties.