Authors

Abstract

Lack of sufficient knowledge about the physical and mechanical properties of onion can result in higher waste during harvesting and post-harvesting. The objective of this work was to determine some physical and mechanical properties of onion cultivated in China. These properties include linear dimensions, mass, shape index, pull-out force, compression and shear forces. The mean longitudinal diameter of bulb (BLD), transverse diameter of bulb (BTD), bulb weight (BW), pull-out force of bulb (BPF), depth of the bulb buried in the soil (BSD), bulb shape index (BSI), diameter of cauloid (CD), circumferential distribution of root systems (RCD), longitudinal length of root systems (RLL) and weight of root systems (RW) were 78.1±9.6 mm, 89.6±10.1 mm, 333.0±101.7 g, 43.9±21.6 N, 35.7±8.7 mm, 1.2±0.1, 15.3±3.7 mm, 89.2±19.7 mm, 42.9±10.0 mm and 0.8±0.4 g. In the study of mechanical properties of onions, the maximum compression force (MCF) required for compression deformation 10mm of bulb was 462.2N, and the maximum shear failure force (MSF) required for shearing of cauloid was 113.8 N. The results of the research will be very useful in the design and optimization of harvest and postharvest machines with reduced waste and damage.

Abstract in Chinese

由于对洋葱基本物理力学特性缺乏充分认知，经常会在收获和产后加工处理时产生较高的浪费。本研究的目标是确定中国栽培洋葱的一些基本物理力学特性。这些特性主要包括线性尺寸、重量、形状、起拔力、压缩力和剪切力。试验结果表明，洋葱鳞茎纵向平均直径、横向平均直径、重量、起拔力、入土深度、形状指数、假茎直径和根系周向分布直径、长度及重量分别为78.1±9.6 mm、89.6±10.1 mm、333.0±101.7 g、43.9±21.6 N、35.7±8.7 mm、1.2±0.1、15.3±3.7 mm、89.2±19.7 mm、42.9±10.0 mm和0.8±0.4 g。力学特性试验表明，洋葱鳞茎压缩变形10mm所用压缩力平均值为462.2N，洋葱假茎剪切破坏所用剪切力平均值为113.8 N。研究结果对于设计优化洋葱收获和产后加工机械及减少损伤浪费有重要价值。