Jie Yang’s research while affiliated with Jilin University and other places

To explore the changes in the cell physiological status of pork tissues at different storage stages, electrical impedance spectroscopy (EIS) was used in this study. The measured impedance values were analyzed with equivalent circuit models consisting of several electrical components. In order to model the complex pork tissues accurately, a constant phase element (CPE) was introduced instead of Cm in the conventional Fricke model to reflect the capacitance of cell membrane. R² values of the real part of impedance were within the range between 0.961 and 0.999, and those for the imaginary part were between 0.730 and 0.999. The results suggested that the modified model with CPE can be further developed to monitor tissues conductivity changes and to evaluate cell physiological status of heterogeneous pork tissues in storage. Control and evaluation of meat maturation state with electrical impedance spectroscopy, which is a convenient and inexpensive method, is feasible and applicable.

The cloud model is a typical model which transforms the qualitative concept into the quantitative description. The cloud model has been used less extensively in texture studies before. The purpose of this study was to apply the cloud model in food crispness comparison. The acoustic signals of carrots, white radishes, potatoes, Fuji apples, and crystal pears were recorded during compression. And three time-domain signal characteristics were extracted, including sound intensity, maximum short-time frame energy, and waveform index. The three signal characteristics and the cloud model were used to compare the crispness of the samples mentioned above. The crispness based on the Ex value of the cloud model, in a descending order, was carrot > potato > white radish > Fuji apple > crystal pear. To verify the results of the acoustic signals, mechanical measurement and sensory evaluation were conducted. The results of the two verification experiments confirmed the feasibility of the cloud model. The microstructures of the five samples were also analyzed. The microstructure parameters were negatively related with crispness (p < .01). Practical applications: The cloud model method can be used for crispness comparison of different kinds of foods. The method is more accurate than the traditional methods such as mechanical measurement and sensory evaluation. The cloud model method can also be applied to other texture studies extensively.