• Korean journal of food and cookery science
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• v.9 no.3
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• pp.181-186
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• 1993

Potato and carrot are the main sourses of vitamin C and vitamin A each. As a folk ramedy, potato-carrot mixtures have been used to cure a stomach ulcer in Korea. To investigate the effects of carrot juice on the browning of potato juice, we examined the brewing in various ratio of two juices. We also investigated the role of potato juice in the carotene oxidation of carrot juice. Delta "L" values of potato juice were abruptly decreased after 5 min. reaction and they were very different from the juice mixture of potato and carrot. Those containing higher ratio of potato were decreased greatly. In blanching treatment to eliminate the effect of the enzymes in potato and carrot, delta "L" values of cooked potato were decreased a little but those of cooked carrot were decreased greatly. To investigate the fact that the inhibitory effect of carrot juice in potato browning was due to the dilution of polyphenolics of potato juices by carrot juice mixing, we added H20 equivalent to carrot water content to potato juice. The diluted sample showed less decreasing pattern than nondiluted sample. We also added appropriate amount of ${\beta}$-carotene to the same samples. Delta "L" values of with added B-carotene were more slowly decreased than those of without added B-carotene.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.12-12
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• 2017

Genetic improvement in potato can be carried out through several approaches, as sexual crosses, somatic hybridization, mutation and genetic engineering. Although the approach is different, but the goal is the same, to get a superior cultivar. Mutation and genetic engineering are very interesting methods for genetic improvement of potato plants. Mutation by gamma-ray irradiation have been performed to get some new potato cultivars which are more resistant to disease and have higher productivity. We have carried out a mutation of some potato cultivars and obtained some excellent clones to be potentially released as new superior cultivars. By the mutation method, we have released one potato cultivar for the French fries industry, and we registered one cultivar of potato for chips, and two cultivar for vegetable potatoes. Actually we are doing multi-location trial for three clones to be released as new cultivars. Through genetic engineering, several genes have been introduced into the potato plant, and we obtained several clones of transgenic potato plants. Transgenic potato plants containing FBPase gene encoding for fructose bisphosphatase, have a higher rate of photosynthesis and higher tuber productivity than non-transgenic plants. This result suggests that FBPase plays an important role in increasing the rate of photosynthesis and potato tuber productivity. Some transgenic potatoes containing the Hd3a gene are currently being evaluated for their productivity. Over expression of the Hd3a gene is expected to increase tuber productivity and induce flowering in potatoes. Transgenic potato plants containing MmPMA gene encoding for plasma membrane ATPse are more tolerant to low pH than non-transgenic plants, indicating that plasma membrane ATPase plays an important role in the potato plant tolerance to low pH stress. Transgenic potato plants containing c-lysozyme genes, are highly tolerant of bacterial wilt diseases caused by Ralstonia solanacearum and bacterial soft rot disease caused by Pectobacterium carotovorum. Expression of c-lyzozyme gene plays an important role in increasing the resistance of potato plants to bacterial diseases.

• Korean journal of food and cookery science
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• v.18 no.6
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• pp.593-602
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• 2002

The objective of this study was to investigate the sensory and quality characteristics of Gamjeobyung containing different ratios of ingredients such as heated potato flour(30%, 40%, 50%), potato starch(30%, 40%), sugar, honey, and water by sensory evaluation and mechanical examination. The results of sensory evaluation showed that Gamjeobyung containing 30% heated potato flour, and potato starch had higher scores in overall acceptability, color, flavor, grain, moistness, chewiness and sweetness preferance. In the textural analysis of Gamjeobyung, the cohesivenss, springiness, adhesiveness were the highest in the samples with 30% potato starch, and the chewiness, gumminess, and hardness were the highest in the 40% added samples. The hunter's color L value and b-value of Gamjeobyung was decreased and a-value was increased of potato starch. The moisture content of Gamjeobyung was higher in the samples with heated potato flour than the samples with potato starch.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.783-788
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• 2007

An advantage to the extrusion of raw potatoes is a reduction in the energy input required to process potato products; however, the effects of extrusion on the properties of raw potato have not been studied. The purposes of this study were to develop a workable extrusion process for raw potato and to study the effects of extrusion conditions on the pasting properties of extruded potato products. The peak viscosity, final viscosity, pasting temperature, water solubility index, and water absorption index of pressed and pressed-dried potato extrudates decreased as die exit temperature increased, whereas they did not change as screw speed increased. The peak viscosity, final viscosity, and water solubility of steam-cooked potato products decreased with extrusion processing; however, they did not change with increasing die exit temperature and screw speed. Potato products with different degrees of depolymerization of extruded potato starch, depending on die exit temperature, were produced from raw potatoes.

• Korean journal of food and cookery science
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• v.23 no.2 s.98
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• pp.227-234
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• 2007

Potato kimchi, fermentation was carried out at $10^{\circ}$C for 15 days using various ratios of potato to kimchi (2.5%, 5%, 10%). The samples were determined according to the fermentation time, pH, acidity and growth of lactic acid bacteria in potato kimchi. The addition ratio of potato to kimchi had little effect on the pH, acidity or growth of lactic acid bacteria in potato kimchi. In comparison to baechu kimchi and mul-kimchi, the pH, acidity and growth of lactic acid bacteria was better in potato kimchi than in the other kimchi samples. The in vitro anticancer effect of potato kimchi was investigated using human cancer cells, AGS human gastric adenocarcinoma cells and HT-29 human colon adenocarcinoma cells. MTT assay revealed that the methanol extract of potato kimchi showed the highest anticarcinogenic effects.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.5
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• pp.769-775
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• 2009

This study was performed to investigate the quality characteristics of yanggeng added with Purple Sweet Potato. The yanggeng was prepared with purple sweet potato, Agar, Sugar and Salt. The yanggeng is made with various levels(0, 2, 4, 6, 8%) of purple sweet potato added. Hunter's color value, texture profile analysis, and sensory characteristics of purple sweet potato yanggeng were examined. The addition of purple sweet potato has tendency to decrease the water content of yanggeng. As the content of purple sweet potato increased, the lightness(L) and yellowness(b) decreased and redness(a) increased. In texture profile analysis, hardness decreased with increasing purple sweet potato content. Cohesiveness and springiness didn't showed significant differences according to amount of purple sweet potato. The results of the sensory evaluation showed that the sweetness, softness and overall acceptability were the highest scores at yanggeng containing 4% level of purple sweet potato. In conclusion, the result shows that the yanggeng with 4% of purple sweet potato is the best.

• Korean journal of food and cookery science
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• v.20 no.3
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• pp.271-278
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• 2004

As an attempt to develop new functional beverages for breakfast, sweet potato based beverages were prepared with hydrolyzed sweet potato, potato, and carrot products (sample : water = 1 : 1), and their chemical and sensory properties were evaluated. The content of reducing sugar and soluble solid of the sweet potato, potato, and carrot increased with enzyme treatment, while their viscosity decreased without significant change of color. The hunter color test showed that the beverages with 10％ carrot content were high in redness leading to a decrease in their acceptability for sensory evaluation. The sensory score of the mixture containing 5％ carrot was good, but beverage with 0％ carrot reduced the sensory properties. The results showed that the final ratio of sweet potato to potato to carrot for the new functional beverage was 5 : 4.5 : 0.5. The pH of the beverage was adjusted to 5.0, 4.5, and 4.0 using an organic acid mixture. In the sensory test of the new functional beverage, the best sensory score(color, taste, smell, and texture) was the mixture of sweet potato : potato : carrot equaling 5 : 4.5 : 0.5 with a pH of 4.5.

• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.478-483
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• 1999

This study was conducted to investigate functional properties of 70% acetone extract in different parts of two potato varieties. 'Superior' and 'Atlantic' potato were processed by following method. Potatoes are washed, peeled, sliced and steamed before hot air drying for flesh and peel powder. Hunter's L and b values of flesh powder from blanched 'Superior' potato were higher than flesh powder from fresh 'Superior' potato. Discoloration of 'Superior' potato was inhibited by steam blanching. Contents of total polyphenol and chlorogenic acid in the 70% acetone extract of 'Superior' potato were higher than those of 'Atlantic' potato paticularly in the blanched flesh and peel. But flavonoid was not detected in flesh extract. The phenolic concentration was not decreased by the heat treatment. The nitritescavenging and electron donating ability was greatest at the tuber peel including the skin and cortex tissue 1mm beneath the skin. From the above results browning reaction and polyphenol contents in different parts of potato slices were dependent on cutivars. Peels contained more polyphenols than those from the flesh. The results indicate that potato peel extract of steam blanched plus hot air dried potato tuber showed the effectiveness as a natural nitrite scavenger and antioxidant.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.197-197
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• 2004

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.183-186
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• 2005

Cryopreservation has been recognized as a practical and efficient tool for the long-term storage of vegetatively propagated plants. This study was conducted to investigate the effects of slow-freezing techniques on the cryopreservation of potato. In vitro plantlets of the potato genotypes of 'Atlantic', 'Superior’, 'Namseo', 'J138', and 'CTO5-5' were cold acclimated, and the excised axillary buds were precultured, osmoprotected, exposed to plant vitrification solution, frozen slowly to $-40^{\circ}C$ and then rapidly plunged into liquid nitrogen, thawed and finally plated on the regeneration medium. It was found that the higher the sucrose concentrations in the subculture medium of donor plantlets, the higher the survival rates of shoot tips after cryopreservation, and the highest survival (20%) was observed in the medium added with 0.25 M sucrose. As for the effect of cooling, $0.3^{\circ}C/min$ cooling speed showed the highest survival (25%). Different varieties showed different responses over different cryopreservation treatments. Survival rate was increased by slow-freezing technique method as compared with that of the basic cryopreservation method of vitrification alone in the diverse potato genotypes. Leaf and tuber morphologies of potatoes regenerated after cryopreservation using slow freezing technique were similar to those derived from the in vitro stock plantlets.