Estimation of concentrations of ternary solution with NaCl and sucrose based on multifunctional sensing technique

Ternary solution with NaCl and sucrose is widely employed in the osmotic dehydration process of food. In this paper, the authors present a novel multifunctional sensor capable of directly sensing temperature and two physical parameters of solutions, namely, ultrasonic velocity and electrical conductivity. By sensing these three parameters, the concentrations (in this study the word "concentration" refers to molality) of two components in ternary solution with NaCl and sucrose can be simultaneously determined. A reconstruction algorithm based on the natural cubic spline interpolation and the least squares method is developed to estimate the concentrations of NaCl and sucrose, in which the temperature influence is first considered, and then, the reconstruction of the concentrations is carried out in three-dimensional (3-D) space [rather than four-dimensional (4-D) space]. The proposed multifunctional sensing technique could prove valuable in the food industry.