Rheological properties of selected food products in the Malaysian market

Food products are complicated mixtures of ingredients which can be scientifically described by rheological measurements. The aim of this study is to evaluate the rheological properties, spreadability and microstructure of commercial processed foods, namely chocolate spread, cheese, chicken rice paste, mayonnaise and chocolate syrup. Cheese, chocolate spread, and mayonnaise had storage modulus (G'.) higher than loss modulus (G") indicating viscoelastic properties and semi-solid form. These products also had compact crystal networking, with G' remaining constant is called the linear viscoelastic region (LVR) and started to drop at higher applied forces (shear stress) as compared to chicken rice paste and chocolate syrup. The oscillatory sweeps test indicated that the viscoelasticity of the products were very much dependent on the type of foods and their microstructural properties. These attributes may also help manufacturers decide on the proper product packaging, storage and method of serving. Therefore, the information obtained from this study would help the food manufacturers to have a better understanding of simple rheological and microstructural properties, which are closely related to the final product properties in terms texture, spreadability and shelf-life.