• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.737-744
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• 2001

This study was carried to investigate the changes in physical and chemical properties during preparation of Yukwa. Protein content of glutinous rice was decreased during soaking time and acid and pH values were increased while contents of lipid and ash were not changed. Particle size distribution showed thate average particle size of 7 days soaking treatment smaller than those of 3 days and starch damage of glutinous rice flour was increased during soaking time. The major flavor components after soaking were found ethyl ester acetic acid, ethanol, 2-butan -ol, 2-methyl 1-propanol, 1-butanol, 3-methyl 1-butanol and 1-pentanol, propanoic acid. Content of acetic acid and butanoic acid were rapidly increased during soaking time. Results for ratio of storage modulus(G') and loss modulus(G') in glutinous rice flour dough indicated $tan{\delta}$ was increased for a while and decreased as frequency increased. G' value was very similar with G' value after steaming which means rubber-like property while G' and G' value were changed after during storage time. Treatment at $-20^{\circ}C$ had the highest hardness for cutting degree of dough. There was no difference in color value between different water contents. Hardness of Bandegi (sheet) was decreased as water content increased and the highest popping value was obtained at 18% of water contents. Adding 3% soaked bean had higher redness value of Yukwa and lower value in yellowness.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.459-468
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• 2019

Changes in growing periods and productivities of crops under double cropping of potato-rice, potato-soybean and potato-maize, were investigated at the Paddy Experimental Fields in Miryang City from 2015 to 2018. Spring potatoes planted in early March showed a yield of 2.1-2.3 ton/10a and a period of 90 days. In double cropping, growing period of rice, soybean, and maize was about 130, 125 and 115 days, respectively. The potato yield obtained was as much as 616, 330 and 815 kg/10a under double cropping with rice, soybean and maize, respectively. It is beneficial to sow the spring potatoes as early as possible to increase the yield and to secure the growing period of sequential crops. The introduction of summer medium-late variety grain crops into double cropping of spring potato and rice as well as into double cropping of spring potato and soybean/maize, was possible because of no sowing in the fall and plants were able to reach the heading growth stage before the safe heading limit of rice in particular. In the case of maize, the growth period was different according to the change in temperature over the year. The introduction of upland crops such as soybeans and maize instead of rice improved soil physicochemical properties in a short period of time, contributing to the increase of spring potato yields, but there was also a risk of damage by successive cropping for more than three years. Spring potato-maize showed higher yield in terms of starch production, and spring potato-soybean was found to be advantageous for net income.