Study On Pectin And Pectin Efficient Extraction Form Carrot

Fraction and changes of pectin substances in five carrot varieties during growth of fruits after being sowed were investigated. It was a reference for carrot breeding. And pectin was extracted from dried carrot by the two methods of sulphuric acid and ultrasonic assistant which in order to find a better condition of pectin extraction and offer some useful information for the pectin extraction industry.The main contributions of the research include:(1) Content of water soluble pectin(WSP),oxalate soluble pectin(OSP)and total pectin(TP)increased with carrot growing, however, different trend showed for content of ASP because of different varieties, which increased or unchanged significantly with development of fruits. The acid soluble pectin(ASP)was the main fraction of pectin substances which reached 75.3%-91.2% of TP, the second OSP,5.8%-17.9% of TP, and the third WSP, 3.0%-8.8% of TP. When being harvested, TP content of Juhong NO.1 was the highest among the five varieties, which reached 12.585 mg/g, but the other four varieties'TP content showed no significant difference (P=0.05). The correlation between firmness of carrot and pectin content and fraction showed no significant difference (P=0.05).(2) There were no difference between degrees of esterification of those five carrot varieties, which were all the high methylation. Juhong NO.1 was the best variety for the pectin extraction because which content of pectin was the highest.(3) Five-factor quadric universal rotational combination design was designed and five independent variables such as granularity, pH, temperature, liquid-solid ratio and time were studied both of sulphuric acid and ultrasonic assistant extraction pectin. The optimal condition of sulphuric acid extraction was granularity0.13mm, pH2, temperature75℃, liquid-solid ratio 25:1, time 90min, pectin jelly units was 62.67 and ultrasonic assistant extraction was granularity0.13mm, pH2, temperature80℃, liquid-solid ratio 35:1, time 30min, pectin jelly units was 73.18.The intrinsic viscosity and average molecular weights was 0.1427 and 110520 which extracted using the optimal condition of sulphuric acid extraction. Ultrasonic assistant extraction pectin used less extraction time, but which attained higher quality pectin compared with the sulphuric acid ectraction at the same temperature condition.