Department of Food Engineering and Process Management, Institute of Food Science, Warsaw University of Life Sciences-SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland.
Division of Food Quality Evaluation, Institute of Food Science, Warsaw University of Life Sciences-SGGW, 159c Nowoursynowska St., 02-776 Warsaw, Poland.
Molecules. 2020 Nov 5;25(21):5146. doi: 10.3390/molecules25215146.
In this study, the impacts of two different pear cultivars, "Conference" and "Alexander Lucas", on the kinetics and the final quality of samples dried by convection (CD) and microwave-convection (MCD) methods, were investigated. The quality of dried material was evaluated by the analysis of water activity, porosity, color, acoustic emission (AE) and mechanical and sensory properties. The required drying time to obtain 0.2 kg HO/kg dry solid (d.s.) was longer for "Conference" than "Alexander Lucas" and was 20 min by CD and 5 min by MCD. The pear cultivar, in conjunction with the drying method (CD or MCD), affected the number of AE events and the work of breaking. The CD pear of the "Conference" cultivar was characterized by higher force, higher breaking work and stronger AE relative to the CD pear of the "Alexander Lucas" cultivar. There were no differences in taste or overall quality, but the hardness was higher for the CD "Conference" pear. A principal component analysis showed that panelists preferred dried fruit with good taste and overall quality but lower hardness. A positive correlation was found between the number of acoustic events and sensory hardness; thus, an acoustic method can be useful for effectively evaluating the texture of dried pears. These results show that the dried pear slices that generated fewer AE events upon breaking were perceived as better by the panelists.
在这项研究中，研究了两种不同的梨品种，“会议”和“亚历山大·卢卡斯”，对对流（CD）和微波对流（MCD）干燥方法样品的动力学和最终质量的影响。通过分析水分活度、孔隙率、颜色、声发射（AE）以及机械和感官特性来评估干燥材料的质量。获得 0.2 kg HO/kg 干固体（d.s.）所需的干燥时间对于“会议”品种来说比“亚历山大·卢卡斯”品种长，CD 干燥需要 20 分钟，MCD 干燥需要 5 分钟。梨品种与干燥方法（CD 或 MCD）结合，影响了 AE 事件的数量和断裂功。与“亚历山大·卢卡斯”品种的 CD 梨相比，“会议”品种的 CD 梨具有更高的力、更高的断裂功和更强的 AE。在口感和整体质量方面没有差异，但 CD“会议”梨的硬度更高。主成分分析表明，品尝者更喜欢口感好、整体质量高但硬度低的干化水果。AE 事件数量与感官硬度之间存在正相关关系；因此，声发射法可用于有效评估干梨的质地。这些结果表明，在断裂时产生较少 AE 事件的干梨片更受品尝者的欢迎。
