Departamento de Ingeniería de Industrias Alimentarias, Universidad Nacional de San Agustín de Arequipa, Arequipa, Peru.
Analysis and Technology of Plant-based Foods, Hochschule Geisenheim University, Geisenheim, Germany.
Food Sci Technol Int. 2021 Jul;27(5):456-469. doi: 10.1177/1082013220963973. Epub 2020 Oct 12.
The objective of this work was to evaluate the stabilisation of betalains and phenolic compounds extracted from red cactus pear by spray and freeze-drying. After hydroethanolic extraction and partial solvent removal under reduced pressure, the highly coloured extracts were enriched with oca starch and maltodextrin as drying aids in different ratios (100:0, 70:30, and 50:50, oca starch: maltodextrin) prior to spray and freeze-drying. The obtained microencapsulated extract powders were characterised by moisture content, hygroscopicity, solubility and morphology. In addition, the stability of the encapsulated betalains and phenolics was evaluated during storage at room temperature for 105 days. All microcapsules showed high retentions of betacyanins (69.9-86.5% after 105 days), betaxanthins (72.2-81.9%), phenolic compounds (46.5-63.5%) and antioxidant capacity (60.1-64.9%, FRAP method; 49.7-57.5%, ABTS method). The system with 70:30 starch:maltodextrin ratio as drying aids showed the highest values of retention regarding the polyphenol content (63.5%), antioxidant capacity (64.9% to FRAP method) and betacyanin content (86.5%), as well as a low degradation rate constant of betacyanins (1.23 × 10 days) and a long half-life (563 days). Oca starch used alone or in combination with maltodextrin has been shown to work adequately as a microencapsulating agent and stabilizer of pigments and antioxidants derived from red cactus pear.
本工作旨在评估喷雾干燥和冷冻干燥对从红色仙人掌梨中提取的甜菜红素和酚类化合物的稳定性的影响。在经水-乙醇提取并在减压下部分除去溶剂后，将高浓度的提取物与秘鲁菝葜淀粉和麦芽糊精混合，并作为干燥助剂，以不同比例（100:0、70:30 和 50:50，秘鲁菝葜淀粉：麦芽糊精）进行喷雾干燥和冷冻干燥。通过水分含量、吸湿性、溶解度和形态对获得的微胶囊提取物粉末进行了表征。此外，还在室温下储存 105 天期间评估了封装的甜菜红素和酚类化合物的稳定性。所有微胶囊均表现出较高的β-花青素保留率（105 天后为 69.9-86.5%）、β-甜菜黄素（72.2-81.9%）、酚类化合物（46.5-63.5%）和抗氧化能力（FRAP 法 60.1-64.9%；ABTS 法 49.7-57.5%）。以 70:30 的淀粉:麦芽糊精比作为干燥助剂的系统在保留多酚含量（63.5%）、抗氧化能力（FRAP 法 64.9%）和β-花青素含量（86.5%）方面表现出最高值，以及β-花青素的低降解速率常数（1.23×10 -1 天）和较长的半衰期（563 天）。单独使用或与麦芽糊精结合使用的秘鲁菝葜淀粉已被证明是一种有效的微胶囊化剂和稳定剂，可用于稳定红色仙人掌梨中的色素和抗氧化剂。
