Authors

Abstract

To investigate the effects of moisture content on the compressive mechanical properties of sweet potato roots, this study used three sweet potato varieties (Zishu, Hongyao, and Xiguahong) cultivated in the Tianjin region as experimental materials. Experiments were conducted between October 8, 2025, and January 8, 2026, in a laboratory environment maintained at 20°C ± 2°C and 50% ± 5% relative humidity. The test employed a moisture content measurement method based on storage duration, measuring moisture content every 10 days. Simultaneously, compressive mechanical property tests were performed using an INSTRON 3344 series universal material testing machine under conditions of a 10 mm/min loading speed and a maximum pressure of 1500 N. The maximum rupture force, maximum deformation, and elastic modulus of sweet potatoes at different moisture contents were determined. Data analysis was conducted using Design-Expert 13 software. The results indicated that the variation patterns of moisture content were similar across the different sweet potato varieties. The moisture content decreased rapidly during the initial storage period, showed a brief increase in the middle stage, and then continued to decline at a slower rate in the later stage. Moisture content significantly affected the compressive mechanical properties of sweet potatoes. As the moisture content decreased, the elastic modulus and maximum rupture force increased, while the maximum deformation decreased.

Abstract in English

为探究水分含量对甘薯块根压缩力学特性的影响，本研究以天津地区种植的紫薯、红瑶、西瓜红三个甘薯品种为试验材料，于 2025 年 10 月 8 日至 2026 年 1 月 8 日，在温度保持为 20℃±2℃、相对湿度保持为 50%±5% 的实验室环境中开展试验。本试验采用基于贮藏时长的水分含量测定方法，每 10 天测定一次甘薯水分含量；同时使用英斯特朗 3344 系列万能材料试验机，在加载速率 10 毫米 / 分钟、最大压力 1500 牛的试验条件下开展压缩力学特性测试，测定不同水分含量下甘薯的最大断裂力、最大变形量及弹性模量，并采用 Design-Expert 13 软件对试验数据进行分析。试验结果表明，不同甘薯品种的水分含量变化规律具有一致性：贮藏初期水分含量快速下降，贮藏中期出现短暂上升，贮藏后期则以较慢速率持续降低。水分含量对甘薯的压缩力学特性存在显著影响，随着水分含量的降低，甘薯的弹性模量和最大断裂力呈上升趋势，而最大变形量呈下降趋势。