• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.149-152
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• 2001

Extraction characteristics of anthocyanin pigment from red flower cabbage(Brassica oleracea L. var. acephala) as a new source of natural food colorant were investigated. The pigment extracted from red flower cabbage showed the characteristic bathochromic shift of the maximum wavelength of light absorption(${\lambda}_{max}$) as pH of the solution changed from pH 1 to 12. As the concentration of citric acid in the extraction solvent increased, extraction rate and total optical density(TOD) of the extract increased. Maximum TOD was obtained by using the extracting solvent including $0.8{\sim}1.0%$ citric acid and stable pigment solution was obtained by using the extracting solvent including $10{\sim}20%$ ethanol in distilled water. As a result, 10% ethanolic solution with 0.8% citric acid was decided as the optimum extraction solvent for the anthocyanin pigment from red flower cabbage. Within the experimental ranges, the extraction rate increased and therefore extraction time decreased as the extraction temperature increased. The times to reach a certain value of TOD i.e., 2.1 were 24, 8, 4 and 2 hours at extraction temperature of 5, 20, 40 and $60^{\circ}C$, respectively.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.221-225
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• 2001

Flow properties of red flower cabbage pigment solutions were determined over a wide range of temperatures ($20-50^{\circ}C$) and soluble solid concentrations (1-65%) using a cone and plate rotational viscometer. Flow properties of the pigment solutions were adequately described by the simple power law model. Within the tested ranges of concentration, temperature and shear rate, the flow behavior index (n) and the consistency index (K) of the solutions were in the ranges of 0.841-0.998 and $0.008-31.525\;Pa{\cdot}s^n$, respectively. The effect of temperature on the apparent viscosity of the solutions followed an Arrhenius type relationship. Activation energy of flow varied from 9.36 to 52.48 kJ/mol depending on the solid concentration and shear rate. The combined effect of temperature and concentration on the apparent viscosity at the shear rate of $100\;s^{-1}$ could be represented by a single equation as ${\ln}\;{\eta}_a\;=\;6.11\;-\;3103.94(1/T)\;-\;0.03C$.

• Journal of the Korean Dietetic Association
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• v.1 no.1
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• pp.2-9
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• 1995

The present study was designed to observe whether nutritional education on children or mothers of the children who avoid to eat vegetables can improve the preferences for the vegetables of the subjects. The subjects were 45 children who are fourth to sixth grade of primary school in Bibong. They were assigned to one of three groups which are Control, Children Education and Mothers Education groups. Control group was not given any special education, while experimental groups were given nutritional education for 4 weeks. The effects of education was evaluated in the aspects of preference changes for vegetables, nutritional knowledge, attitude and food behavior of the subjects The results are summarized as follows. 1. Preferences to cucumber, lettuce, chinese cabbage and raddish were high in three groups while greenonion, onion, lotus roots and red pepper didn't suit for their taste. 2. Significantly increased scores for the preference to red pepper, pumpkin, Dorajee(root of chinese bell-flower), braken, mushroom was shown only in the children who had nutritional education while the children in the group of Mothers Education improved their preference only cabbage and lotus roots. 3. Nutritional knowledge of the children in Children Education group has improved significantly(p<0.05). While there was no significant difference between control and Mothers Education group. 4. When scores for food habit of mother and children were estimated, there was no significant difference among three groups. However, score of food habit in children was higher than that of mothers. 5. Food habit and nutrition knowledge of mother were not well corelated with dietary attitude and behavior of their children. These results indicate that the program of nutrition education in the present study can improve the food choice of children for vegetable and correct one-sided food habit. The program applied in this study would serve a kind of model for the dietetic teachers to guide the children who mainly dislikes vegetables.

• Food Science and Preservation
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• v.7 no.3
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• pp.285-290
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• 2000

Color values of anthocyanins from seven natural food colorants, such as purple-fleshed sweet potato (PSP), red flower cabbage (RFC), red cabbage (RC), grape skin (GS), black rice (BR), egg plant (EP), and fig fruit (FF) were evaluated, resulting in the selection of four color sources with higher color values including PSP, RFC, RC and GS. The stabilities of anthocyanins from the selected colorant sources against metal ions, ascorbic acid, ultra-violet light, and heating were investigated. Anthocyanins from PSP and GS were degraded significantly by $Mn^{2+}$, while those from RFC and RC were degraded by $Cu^{2+}$. Asthocyanins from PSP were the most stable against the color-degrading factors, followed by RFC, RC, and GS in descending order.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.103-134
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• 1977

The physiological and biochemical role of potassium for upland crops according to recent research reports and the nutritional status of potassium in Korea were reviewed. Since physical and chemical characteristics of potassium ion are different from those of sodium, potassium can not completely be replaced by sodium and replacement must be limited to minimum possible functional area. Specific roles of potassium seem to keep fine structure of biological membranes such as thylacoid membrane of chloroplast in the most efficient form and to be allosteric effector and conformation controller of various enzymes principally in carbohydrate and protein metabolism. Potassium is essential to improve the efficiency of phoro- and oxidative- phosphorylation and involve deeply in all energy required metabolisms especially synthesis of organic matter and their translocation. Potassium has many important, physiological functions such as maintenance of osmotic pressure and optimum hydration of cell colloids, consequently uptake and translocation of water resulting in higher water use efficiency and of better subcellular environment for various physiological and biochemical activities. Potassium affects uptake and translocation of mineral nutrients and quality of products. potassium itself in products may become a quality criteria due to potassium essentiality for human beings. Potassium uptake is greatly decreased by low temperature and controlled by unknown feed back mechanism of potassium in plants. Thus the luxury absorption should be reconsidered. Total potassium content of upland soil in Korea is about 3% but the exchangeable one is about 0.3 me/100g soil. All upland crops require much potassium probably due to freezing and cold weather and also due to wet damage and drought caused by uneven rainfall pattern. In barley, potassium should be high at just before freezing and just after thawing and move into grain from heading for higher yield. Use efficiency of potassium was 27% for barley and 58% in old uplands, 46% in newly opened hilly lands for soybean. Soybean plant showed potassium deficiency symptom in various fields especially in newly opened hilly lands. Potassium criteria for normal growth appear 2% $K_2O$ and 1.0 K/(Ca+Mg) (content ratio) at flower bud initiation stage for soybean. Potassium requirement in plant was high in carrot, egg plant, chinese cabbage, red pepper, raddish and tomato. Potassium content in leaves was significantly correlated with yield in chinese cabbage. Sweet potato. greatly absorbed potassium subsequently affected potassium nutrition of the following crop. In the case of potassium deficiency, root showed the greatest difference in potassium content from that of normal indicating that deficiency damages root first. Potatoes and corn showed much higher potassium content in comparison with calcium and magnesium. Forage crops from ranges showed relatively high potassium content which was significantly and positively correlated with nitrogen, phosphorus and calcium content. Percentage of orchards (apple, pear, peach, grape, and orange) insufficient in potassium ranged from 16 to 25. The leaves and soils from the good apple and pear orchards showed higher potassium content than those from the poor ones. Critical ratio of $K_2O/(CaO+MgO)$ in mulberry leaves to escape from winter death of branch tip was 0.95. In the multiple croping system, exchangeable potassium in soils after one crop was affected by the previous crops and potassium uptake seemed to be related with soil organic matter providing soil moisture and aeration. Thus, the long term and quantitative investigation of various forms of potassium including total one are needed in relation to soil, weather and croping system. Potassium uptake and efficiency may be increased by topdressing, deep placement, slow-releasing or granular fertilizer application with the consideration of rainfall pattern. In all researches for nutritional explanation including potassium of crop yield reasonable and practicable nutritional indices will most easily be obtained through multifactor analysis.