Relationship between Major Components and Physicochemical Properties of Radish (Raphanus sativus L.) Combinations for Developing New Cultivars Targeting Chinese Market

Major components including total phenolic compounds, cellulose, starch and soluble sugar and physicochemical properties of radish breeding combinations were determined and statistically analyzed to evaluate their relationship and to develop radish cultivars targeting foreign market. Sixteen radish combinations selected for Chinese market were analyzed in color and total phenolic compounds, texture and cellulose, beta-amylase activity and starch/soluble sugars. In addition, relationship between each component was estimated using Pearson correlation coefficients. Total phenolic contents of radish were 26.0 +/- 3.0 mg gallic acid equivalent per gram dry weight (dw). Correlation between brightness of surface and the total phenolic content was negative, but redness or yellowness showed positive correlation. Cellulose and starch contents were 17.9 +/- 2.6 g/100 g dw and 3.06 +/- 1.08 g/100 g dw, respectively. Those contents and the cutting force of radish showed positive relationship, but according to Pearson correlation coefficient, it was not statistically significant. Activity of beta-amylase was 93.2 +/- 38.0 total unit/g dw in average, and soluble sugar was detected as 195 +/- 49 mg.g(-1) dw. Unexpectedly, the beta-amylase activity and starch or soluble sugar contents showed no statistically significant correlation, which might be due to very short storage time of radishes before analysis. These results could be valuable information for the development of radish cultivars applicable for dried radish targeting Chinese market.