When frying foods, volume changes appear as shrinkage that can affect their physical properties including density and porosity, which are both important factors for heat and mass transfer. Challenges faced in heat and mass transfer while processing foods are associated with shrinkage. It is thus necessary to analyse and quantify structural changes in foods (such as shrinkage) to better understand the transfer mechanisms and their modelling. The use of ultrasound pretreatment is a promising method to improve the qualitative and quantitative properties of fried products, including decreased sample shrinkage rate. In this regard, the effect of ultrasonic pretreatment at two frequencies (20 and 40 kHz) for 15 min on the moisture content (MC) and shrinkage of potato slices, which were deep-fried at 175 °C and 195 °C for 3, 4 and 5 min, was investigated. The samples pretreated at 40 kHz had lower MC and shrinkage than the other samples. Sample MCs decreased with temperature and frying time but shrinkage increased. Six models were used for predicting shrinkage in samples. The best model (a rectangular hyperbola) was selected based on R² and \( {\mathcal{X}}^2 \) and its coefficients were quantified using nonlinear regression analysis.

油炸食物时，体积变化表现为收缩，会影响其物理性质，包括密度和孔隙率，这都是传热和传质的重要因素。食品加工过程中传热和传质面临的挑战与收缩有关。因此，有必要分析和量化食物的结构变化（例如收缩），以更好地了解转移机制及其模型。超声预处理的使用是改善油炸产品定性和定量特性（包括降低样品收缩率）的一种有前途的方法。在这方面，在175°C和195°C的温度下油炸3次的两个频率（20和40 kHz）的超声预处理15分钟对马铃薯片的水分（MC）和收缩率的影响，研究了4和5分钟。在40 kHz预处理的样品比其他样品具有更低的MC和收缩率。样品MC随温度和油炸时间而降低，但收缩率增加。使用六个模型来预测样品的收缩。根据以下最佳模型（矩形双曲线）进行选择使用非线性回归分析对R ²和\（{{mathcal {X}} ^ 2 \）及其系数进行量化。