Kinetics Of Acid And Ultrasonic Extraction On Carrot Pectin

The extraction process of pectin had two simultaneous transformation, i.e., the transformation of the protopectin into the soluble pectin and the degradation of part of the soluble pectin, how to quantitatively describe its extraction and degradation process which was regarded as the theoretical basis that explanted and controlled the change of pectin under the related technology condition. Recently, studies indicated that pectin from carrot was developable and valuable, so this research took the"ju hong yi hao"carrot as a raw material, studied the kinetics of the conventional acid and ultrasonic-assisted extraction on pectin according to panchev's model, and described system the effect of the extraction factor - material granularity, temperature, liquid-solid ratio, pH, time on the pectin quality and the extraction speed. These main results of this study show as follows:1 Through quadratic regression orthogonal rotational combing design, studied material granularity, temperature, liquid-solid ratio, pH to the rate coefficient ky1 of dissolve reaction, the rate coefficient ky2 of degradation reaction, the pectin quality variation coefficient kju1 of dissolve reaction, the pectin quality variation coefficient kju2 of degradation reaction in the acid extraction on carrot pectin. There were extremely significant effects of granularity, temperature on ky1 (p<0.01) and significant effects of pH on ky1 (p<0.05) while no evident impact of liquid-solid ratio on ky1 (p>0.05). There were extremely significant effects of granularity, temperature and pH on ky2 (p<0.01) while no evident impact of liquid-solid ratio on ky2 (p>0.05).Only granularity was extremely significant factor for kju1(p<0.01)while no evident impact of temperature, pH ,liquid-solid ratio on kju1 (p>0.05); granularity, temperature and pH were extremely significant factors for kju2(p<0.01) while no evident impact of liquid-solid ratio on kju2 (p>0.05).2 Selected material granularity 0.53mm, temperature 80℃, the liquid-solid 25:1, pH 1.76, and obtained the change of pectins with the time in the acid extraction, under this condition the pectin intrinsic viscosity were 0.1235~0.1738m3/kg.3 Studied the effect of ultrasonic power (200w, 300w, 400w, 500w) and frequency (26kHz, 70kHz) on the yield of carrot pectin, viscosity and the jelly units, the result indicated there were extremely significant effect of frequency and power on the yield of carrot pectin, viscosity, the jelly units(p<0.01), and the correlation between them was significant extremely(p<0.01); there was better at the yield of carrot pectin, viscosity, the jelly unit in 26kHz-400w than the other of the ultrasonic treatments, respectively was 7.07%, 4.89mm2/s, 34.56.4 Through quadratic regression orthogonal rotational combing design, studied material granularity, temperature, liquid-solid ratio, pH to the rate coefficient ky1 of dissolve reaction, the rate coefficient ky2 of degradation reaction , the pectin quality variation coefficient kju1 of dissolve reaction, the pectin quality variation coefficient kju2 of degradation reaction in the ultrasonic-assist extraction on carrot pectin. There were extremely significant effects of granularity and temperature on ky1 and ky2 (p<0.01) while no evident impact of pH and liquid-solid ratio on ky1 (p>0.05). Granularity, temperature and pH were extremely significant factors for kju1 (p<0.01) while no evident impact of liquid-solid ratio on kju1 (p>0.05); granularity, temperature were extremely significant factors for kju2 (p<0.01) and pH was significant factors for kju2 (p<0.05) while no evident impact of liquid-solid ratio on kju1 (p>0.05).5 Selected material granularity 0.53mm, temperature 60℃, the liquid-solid ratio 25:1, pH 2.00, 26kHz and 400w, obtained the change of pectins with the time in the ultrasonic extraction, under this condition, the pectin intrinsic viscosity were 0.1333~0.1596m3/kg.