Polyphenols are commonly retrieved from plant material with solid-liquid extraction, the optimization of which requires fundamental laboratory-scale investigation, to clearly identify variables and variable levels crucial to the process. When performing scaling-up, the process result should be the anticipated one, irrespective of the scale adopted. However, the use of different equipment (extractor) might affect key parameters pertaining to extraction performance, providing diversified outcome for the same plant matrix extracted with a given solvent. To test this hypothesis, potato peels were chosen as a model plant matrix and extraction optimization was carried out using water/ethanol mixtures. All process variables (ethanol concentration, liquid-to-solid ratio, stirring speed) were maintained unchanged, except for extractor volume, which varied from 25 to 250 mL, and stirring bar length, which varied from 19 to 40 mm. The set of optimized values in each case was different, illustrating the effect of extractor dimensions on the extraction optimization. However, extraction yield in total polyphenols was essentially the same in cases examined. Kinetics also revealed that depending on the extractor volume and stirring bar length, extraction rate constant and diffusivity may be significantly impacted. Notable differences were also found in the major potato peel polyphenols, chlorogenic and caffeic acids, but these differences were not reflected on the antioxidant characteristics of the extracts, which were virtually unaffected. This study demonstrated for the first time that extractor dimensions affect significantly the settings of optimization of stirred-tank polyphenol extraction on a laboratory scale, leading to diversified conclusions.

通常通过固液萃取从植物材料中回收多酚，要对其进行优化，需要对实验室规模进行基本调查，以清楚地识别对过程至关重要的变量和变量水平。进行放大时，无论采用何种规模，处理结果都应该是预期的结果。但是，使用不同的设备（提取器）可能会影响与提取性能有关的关键参数，从而为使用给定溶剂提取的同一植物基质提供了多样化的结果。为了验证该假设，选择马铃薯皮作为模型植物基质，并使用水/乙醇混合物进行提取优化。除了提取器体积，所有工艺变量（乙醇浓度，液固比，搅拌速度）保持不变外，从25毫升到250毫升不等，搅拌棒长度从19毫米到40毫米不等。在每种情况下，优化值的集合都不同，这说明了提取器尺寸对提取优化的影响。但是，在所检查的情况下，总多酚的提取率基本相同。动力学还显示，取决于萃取器的体积和搅拌棒的长度，萃取速率常数和扩散率可能会受到显着影响。在主要的马铃薯皮多酚，绿原酸和咖啡酸中也发现了显着差异，但这些差异并未反映在提取物的抗氧化特性上，这些特性实际上并未受到影响。