Aim: Optimum conditions of umbu juice spray drying were selected using inlet air temperature (T), feed flow rate (F) and 10-DE maltodextrin concentration (CMD) as independent variables, and water activity, moisture content, hygroscopicity and phenolic compounds retention as responses.Methods: Powders water activity was determined with a water activity metre, moisture content and hygroscopicity gravimetrically, total phenolics spectrophotometrically, apparent and absolute density, porosity and solubility by standard methods, particle size by laser diffraction, and morphology by Scanning Electron Microscopy. Nectars sensory analysis was based on acceptance, purchase intention and multiple comparison preference tests. Powder stability was checked at 25 °C varying water activity and storage time in the ranges 0.1-0.3 and 30-90 days, respectively.Results: Powders prepared at T = 110 °C, F = 0.84 L/h, CMD=10% and T = 140 °C, F = 0.60 L/h, CMD=10% gave the best microparticles and sensory results. The former showed properties suitable for industrial production.Conclusion: These findings may promote umbu powder industrial exploitation.

中文翻译：

---

优化umbu果汁喷雾干燥，并对雾化粉进行理化，微生物和感官评估。

目的：使用入口空气温度（T），进料流速（F）和10-DE麦芽糊精浓度（CMD）作为自变量，并选择水活性，水分含量，吸湿性和酚类化合物保留量，来选择umbu果汁喷雾干燥的最佳条件方法：以粉末的水分活度，水分含量和吸湿性，重量酚，分光光度法，表观和绝对密度，孔隙率和溶解度（通过标准方法），粒度（通过激光衍射）和形态（通过扫描电子显微镜）测定粉末的水分活度。 。花蜜的感官分析基于接受度，购买意愿和多重比较偏好测试。在25°C下检查粉末稳定性，改变水活度和储存时间分别为0.1-0.3天和30-90天。结果：在T = 110°C，F = 0.84 L / h，CMD = 10％和T = 140°C，F = 0.60 L / h，CMD = 10％下制备的粉末具有最佳的微粒和感官效果。前者显示出适合工业生产的特性。结论：这些发现可能促进umbu粉的工业开发。