Novel Strategies for the Functional Replacement of Milk Fat in Processed Cheese Products

Date

2017-08-30

Authors

Ramel, Pere Randy Jr.

Journal Title

Journal ISSN

Volume Title

Publisher

University of Guelph

Abstract

This research project is aimed at reducing saturated and trans fats in processed cheese products (PCPs) by replacing milk fat (MF) with lower cost, more sustainable, and higher nutritional value fat replacements. By studying the crystal structure of MF in bulk at different length scales, and understanding MF crystallization within PCPs, we were able to gain insights into strategies that can be used to replace MF while keeping the desirable characteristics of PCPs such as suitable firmness, good oil stability, and sufficient meltability or spread upon heating. For MF crystal structure in bulk, the nanostructure of MF was characterized by describing the properties and aggregations of crystalline nanoplateletes (CNPs), which are the primary crystals that make up large microstructures of MF. A concentration-temperature map for engineering the microstructure of MF by blending binary and ternary mixtures of MF melting fractions was also generated. For MF structure within a food matrix, the polymorphism of MF within commercial PCPs was characterized. A higher ratio of the most stable crystal polymorph of MF, the beta form, was found in PCPs, while MF in bulk was mostly in the beta-prime polymorph. Using a model cheese system, we suggested that the dispersion of MF globules in a solid protein matrix results in more beta polymorph formation due to crystallization in a confined space. More than polymorphism, microstructure was greatly correlated with the rheological properties of PCPs. PCP microstructure can be considered as a polymer composite matrix, where fat globules are distributed as particle fillers in a continuous protein matrix. MF was then substituted with various edible particle fillers and canola oil. We found that oat fiber (OF) particles performed best in reinforcing the microstructure of model imitation cheese products compared to other non-fat particles and fat blends studied. Oil loss and melting properties of products with canola oil and added OF were not significantly different from that of imitation cheese with MF. Mechanisms describing how OF provides these functionalities were also described using rheology.

Description

Keywords

Milk Fat, Processed Cheese, Canola Oil, Oat Fiber

Citation