Microstructure and rheology of apple jam as influenced by cross-linked acetylated starch

The micro-structural changes of jams containing different amounts of cross-linked acetylated starch (CAS) have been studied using rheological measurements, sensory evaluation, scanning electron microscopy (SEM), and laser particle analysis. The results indicated that all samples exhibited pseudoplastic flow with yield stress. Subsequent dynamic oscillatory rheological study also showed that jam structure was more compact in the presence of 20% CAS. SEM analysis demonstrated that there was a fine, homogeneous network in the microstructure of apple jams. Furthermore, it was found that the particle size was smaller after adding CAS. Therefore, we conclude that CAS could be an appropriate gelling agent for apple jams, and the most suitable CAS content for industrial manufacturing was 20%.