Luo Xuan, Xu Huirong, Ye Zunzhong
College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China.
Key Laboratory of on Site Processing Equipment for Agricultural Products, Ministry of Agriculture and Rural Affairs, Hangzhou, China.
J Texture Stud. 2025 Oct;56(5):e70041. doi: 10.1111/jtxs.70041.
Penetration test is the most direct and widely recognized standard method for assessing fruit firmness. Texture analyzers are increasingly employed for accurate fruit firmness measurement, offering advantages in reducing operator errors compared to the traditional manual test. The diverse options of texture analyzers provide flexibility for users, but also present challenges for standardizing firmness measurements. In addressing these issues, factors influencing firmness characterization, including peeling, probe size, penetration speed, penetration depth, and measurement parameters were analyzed for peach and nectarine. The results show that, compared to skin-off parameters, skin-on parameters exhibited absolute advantages for the nectarine cultivar. We also found the importance of probe size selection for accurate firmness detection for different cultivars, and it appears to be closely related to whether the fruits were peeled. The peach cultivar "HJ" is suitable for using a thicker probe (8 mm) after peeling, while the nectarine cultivar "ZNJH" is suitable for using a relatively thin probe (5 mm) with the skin on. The influence of speed is relatively low; however, a penetration speed of 5 mm/s is more recommended due to its better performance in capturing firmness differences. The force values at the steady phase of force-displacement curves perform best among all tested parameters. Penetration depths of 8 and 10 mm show no significant difference, suggesting that once the steady phase is reached, the influence of penetration depth is minimal.
穿刺试验是评估果实硬度最直接且被广泛认可的标准方法。质地分析仪越来越多地用于精确测量果实硬度，与传统手动测试相比，它在减少操作人员误差方面具有优势。质地分析仪的多种选择为用户提供了灵活性，但也给硬度测量的标准化带来了挑战。在解决这些问题时，针对桃和油桃分析了影响硬度表征的因素，包括去皮、探头尺寸、穿刺速度、穿刺深度和测量参数。结果表明，与去皮参数相比，带皮参数对油桃品种具有绝对优势。我们还发现了选择探头尺寸对于不同品种准确检测硬度的重要性，这似乎与果实是否去皮密切相关。桃品种“HJ”去皮后适合使用较粗的探头（8毫米），而油桃品种“ZNJH”带皮时适合使用相对较细的探头（5毫米）。速度的影响相对较小；然而，由于在捕捉硬度差异方面表现更好，更推荐5毫米/秒的穿刺速度。在所有测试参数中，力-位移曲线稳定阶段的力值表现最佳。8毫米和10毫米的穿刺深度没有显著差异，这表明一旦达到稳定阶段，穿刺深度的影响最小。
