Extraction,Purification And Application Of Anthocyanins In Purple Eggplant Skin

The extraction, purification, structure, stability and application of five parts of anthocyanins from purple long eggplant were studied and discussed. The main contents were as follows:In the extraction process, the organic solvent extraction and ultrasonic assisted extraction were compared, respectively, the effect of the extraction rate of anthocyanins in purple eggplant peel was discussed. Taking the extraction rate as the index, through the various factors were the single factor experiment and response surface method optimization analysis to determine the optimal conditions for the extraction of organic solvent extraction method eggplant purple skin anthocyanin was:144 minutes of extraction time, ethanol volume fraction of 61%, solid-liquid ratio 50:1 ml/g. At the same time, the anthocyanin extraction rate of 1.13%; ultrasonic assisted solvent extraction method, the optimum conditions for:ultrasonic power of 350W, liquid material ratio of 60:1 ml/g, ethanol volume fraction 60%, ultrasonic time 42 min, final anthocyanin extraction rate was 1.82%.Purification of anthocyanin extracted from purple eggplant peel by macroporous resin purification, through the static adsorption-desorption experiment to screen macroporous resin, combined with the static/dynamic adsorption desorption experiment to optimize the purification process. The results showed that three kinds of macroporous resins, AB-8 macroporous resin was the most suitable adsorbent for purple eggplant skins astaxanthin purification. The optimal conditions of adsorption:adsorption time 1.0 h,260 ml sample volume of anthocyanin, adsorption flow rate of 1 ml/min; for the optimum analytical conditions, analytical time 1.0 h, elution liquid ethanol volume fraction was 40%, eluent volume was 80 ml, adsorption flow rate 1 ml/min.By UV-Vis, IR, HPLC to identify the main structure of anthocyanin of purple eggplant. The main structure was determined cyaniding-3-O-glucoside. The content of anthocyanin in purple eggplant peel was 16.3%.In purple eggplant skins anthocyanin stability test, the effect of temperature, pH, oxidation/reduction of substances, preservatives, metal ions, sugars and other conditions on anthocyanin stability from purple eggplant skin were investigated. The results show that the purple eggplant anthocyanins should be avoided from the light conditions to preserve at 4℃ pH 1.0, Anthocyanins can form metal complexes with Fe3+, which affect the stability of anthocyanins.and in the storage process should avoiding contact with iron container. Eggplant purple anthocyanin was very sensitive to H2O2 and sodium benzoate, using process should avoid existing. In addition, purple eggplant anthocyanin on sugar stable, production can be added.Optimal formula of anthocyanin from purple eggplant skin gel candy:mixed gel add was 4.62%, citric acid added 1.80% and anthocyanin added 5.73%, sugar adding 8.53%. Under this condition,the comprehensive score was 94.44.