Korea. Two kinds of jochung products were prepared from steamed rice(SR) and wet-milled rice flour(WRF) by rice cultivated from 2006 to 2010. It is common to add a liquefying enzyme for rice liquefaction(4 ㎖/1, 000 g rice, at 90～95℃, 3 h) and saccharogenic enzyme with malt(45 g/1, 000 g rice, at 55～57℃, 6 h). In order to evaluate the quality characteristics of jochung, producing rate, pH, solidity, reducing sugar, dextrose equivalence(D.E.), viscosity, total phenolic compound, color value and sensory evaluation were carried out. In terms of the producing rate of jochung, WRF jochung was produced about 7.4% much more than SR jochung. There was no difference in producing rate between the jochung cultivated from 2006 to 2010 rice. The pH varied from 4.86～5.66, solidity was 79.48～82.28%. Color L value was 25.82～27.92, a value of 1.28～2.81, b value were 2.98～4.33. The results of sensory evaluation for jochung, as a whole, received higher score than for the commercial product(Daesang Co., Ltd, Seoul, Korea), overall acceptability score was the highest in the 2008SR. Reducing sugar, dextrose equivalence(D.E.) and total phenolic compounds were determined to be higher WRF jochung than SR jochung, while viscosity was lower WRF jochung than SR jochung. These results are thought to be due to increased surface area of rice by milling. SR jochung manufacturd by wet-milled rice flour will increase the producing rate for jochung, thereby saving manufacturing time and costs.

This study aimed to compare the quality characteristics of developed rice Jochung (E) with those of commercial-rice Jochung (A, B, C, and D). The total soluble solid, reducing sugar, and dextrose equivalent of developed rice Jochung were 80 °Brix, 44.53%, and 56.94%, respectively. The pH and titrable acidity were 6.25 and 0.19%, respectively. The color difference value (ΔE) of developed rice Jochung was 74.42, which was significantly lower than the other samples investigated. The light transmittance and total polyphenol contents of developed rice Jochung were 56.4%T and 108.23 mg GAE/100 g, respectively. The adhesiveness values of various commercial-rice Jochung products were 29.0~66.0 sec, while that of developed-rice Jochung was 61 sec, showing good textural properties for use in manufacturing Hangwa, a Korean traditional cookie. The electron-donating values of various rice Jochung were 20.4~50.3%, among which the developed-rice Jochung showed the highest value. The reducing powers of various rice Jochung products were 0.44~0.72, while that of the developed product was 0.72, which was significantly higher than the other values. Sensory evaluation revealed that the color scores of developed- and commercial-rice Jochung products were 6.70~6.80. Flavor scores of rice Jochung products ranged from 6.00 to 7.00. Taste and mouth feeling scores of developed-rice Jochung did not significantly differ from those of commercial Jochung products. Compared to commercial-rice Jochung products, developed-rice Jochung made with malt extract exhibited high polyphenols content. However, there were no significant differences in the overall acceptability scores between commercial-rice Jochung products and the developed product. The developed-rice Jochung analyzed in this study may be useful as a traditional sweetener for various Hangwa products as a substitute for corn syrup or Jochung.