Effect of hydrocolloid type on transfer phenomena during deep-fat frying of coated potato strips: Numerical modeling and experimental analysis

Numerical simulation is a valuable tool to predict the behavior of systems as well as to optimize and control various food processes. The main aim of this work was to develop a 3-D model to numerically simulate momentum, heat, and mass transfer during deep-fat frying of coated potato strips with a particular focus on the influence of hydrocolloid type. The samples were pre-treated with different hydrocolloids (sodium alginate, Arabic gum, and carrageenan) separately and then fried at different positions of fryer. In order to validate the model, experimental measurements of moisture content (MC), oil uptake (OU), core (T-co) and surface (T-surf) temperatures of potatoes, and oil temperature (T-0) were carried out. Oil velocity ((u) over right arrow (0)) was also simulated. The results indicated that profiles of dependent variables were not significantly (p > 0.05) affected by four positions of the samples in the fryer. The MC and OU were significantly lower in coated potatoes (p < 0.05) compared to non-coated samples. Sodium alginate was more effective than two other gums in decreasing OU. In addition, the rates of T-co and T-surf increased in the samples and T-0 and <(u)over right arrow>(0) distributions were influenced by pre-treatment. The maximum values of computed (u) over right arrow (0) were 5.41 x 10(-3)-5.57 x 10(-3) m/s during frying of different potato strips. A comparison of model predictions and experimental data showed their overall good agreement (except for OC with mean relative error > 20%). Generally, the findings of this work may be used to provide further insights into the influence of hydrocolloid type on transfer phenomena during frying. It may also be valuable to better understand the process and improve quality of fried coated food.