Chemical and Food Engineering Department, Federal University of Santa Catarina, EQA/UFSC - CP 476, CEP 88040-900 Florianópolis, SC, Brazil.
Bioresour Technol. 2010 Jul;101(14):5622-32. doi: 10.1016/j.biortech.2010.02.020. Epub 2010 Mar 3.
Peach kernels are industrial residues from the peach processing, contain oil with important therapeutic properties and attractive nutritional aspects because of the high concentration of oleic and linoleic acids. The extraction method used to obtain natural compounds from raw matter is critical for product quality definition. Thus, the aim of this work was to compare peach almond extraction yields obtained by different procedures: soxhlet extractions (Sox) with different solvents; hydrodistillation (HD); ethanolic maceration (Mac) followed by fractionation with various solvents, and supercritical fluid extraction (SFE) at 30, 40 and 50 degrees C and at 100, 200 and 300bar, performed with pure CO(2) and with a co-solvent. The extracts were evaluated with respect to fatty acid composition (FAC), fractionated chemical profile (FCP) and total phenolic content (TPC). The Sox total yields were generally higher than those obtained by SFE. The crossover pressure for SFE was between 260 and 280bar. The FAC results show oleic and linoleic acids as main components, especially for Sox and SFE extracts. The FCP for samples obtained by Sox and Mac indicated the presence of benzaldehyde and benzyl alcohol, components responsible for almond flavor and with important industrial uses, whereas the SFE extracts present a high content of a possible flavonoid. The higher TPC values were obtained by Sox and Mac with ethanol. In general, the maximum pressure in SFE produced the highest yield, TPC and oleic acid content. The use of ethanol at 5% as co-solvent in SFE did not result in a significant effect on any evaluated parameter. The production of peach almond oil through all techniques is substantially adequate and SFE presented advantages, with respect to the quality of the extracts due to the high oleic acid content, as presented by some Sox samples.
桃仁是桃加工的工业残渣，含有具有重要治疗特性的油，并且由于高浓度的油酸和亚油酸，具有有吸引力的营养方面。从原料中获得天然化合物的提取方法对于产品质量定义至关重要。因此，本工作的目的是比较不同方法提取桃仁的提取率：不同溶剂的索氏提取（Sox）；水蒸馏（HD）；乙醇浸渍（Mac）后用不同溶剂进行分级，以及在 30、40 和 50°C 和 100、200 和 300bar 下用纯 CO(2)和共溶剂进行超临界流体提取（SFE）。提取物的脂肪酸组成（FAC）、分级化学图谱（FCP）和总酚含量（TPC）进行了评估。 Sox 的总提取率通常高于 SFE 的提取率。SFE 的交叉压力在 260 和 280bar 之间。FAC 结果表明油酸和亚油酸是主要成分，尤其是 Sox 和 SFE 提取物。 Sox 和 Mac 提取样品的 FCP 表明存在苯甲醛和苯甲醇，这是杏仁风味的组成部分，具有重要的工业用途，而 SFE 提取物则含有高含量的可能黄酮类化合物。 Sox 和 Mac 用乙醇获得的 TPC 值较高。一般来说，SFE 中的最高压力会产生最高的提取率、TPC 和油酸含量。在 SFE 中使用 5%乙醇作为共溶剂并没有对任何评估参数产生显著影响。通过所有技术生产桃仁油的产量都相当充足，SFE 具有优势，由于高油酸含量，提取液的质量得到改善，一些 Sox 样品就是如此。
