Microstructure-texture relationships of aerated sugar gels: Novel measurement techniques for analysis and control

Abstract

Proper control of the texture properties of aerated foods demands accurate measurement tools. Aerated sugar gels with identical composition but different microstructures were produced by applying different mixing times of 2, 4 and 8 min. Compression test and acoustic emission measurements were carried out to characterize the mechanical properties of these foams. Significant differences in deformation properties and number of acoustic events were found depending on the foaming time, indicating differences in texture. Microstructural attributes such as bubble size and bubble number distributions of the different foams were measured based on micro- and nano-CT and were found to differ between the foams. Additionally, time and spatially resolved diffuse spectroscopy were used to evaluate their optical properties. While, as expected for foams with the same chemical composition, the absorption properties were not significantly different, a relationship between scattering and microstructural properties was found. The results show that microstructural properties affect the texture of aerated foams. Moreover, the latter can be measured nondestructively using time and spatially resolved diffuse spectroscopy.