Optimization of Preparation Technology of Microencapsulation of Oligomeric Proanthocyanidins from Red Raspberry Seeds and Its Stability Analysis

A new method for preparation of microencapsulated oligomeric proanthocyanidins from red raspberry seeds by complex coacervation was established, aiming to improve the stability of oligomeric proanthocyanidins. The preparation of oligomeric microcapsuls of red raspberry seeds with oligomeric proanthocyanidins as core material and gelatin and gum arabic as wall material was optimized by single factor and response surface test. The stability of the native and microencapsulated oligomeric proanthocyanidins was compared. Results showed that the oligomeric proanthocyanidins microcapsule technology was:wall material concentration 0.75%, arabic quality (gelatin/gum) ratio 1:1, core/wall material quality ratio 1.05:1, curing temperature 10℃, transglutaminase dosage 22.39 g/100 g, gelatin and the embedding rate could reach 80.34%. The moisture content, repose angle, solubility and particle size of the microcapsules was 5.64%, 36.4°, 89.64% and 476 nm. Under the influence of V_C, sodium bisulfite, temperature, pH and light, the stability of oligomeric proanthocyanidin microcapsules after the inclusion was significantly higher than that before the inclusion. Therefore, microencapsulation was high stability of oligomeric proanthocyanidins, which broadened the application of oligomeric proanthocyanidins microcapsuls of red raspberry seeds.