Effect of Emulsifying Salts on Casein Peptization and Apparent Viscosity of Processed Cheese

Abstract

The influence of five different emulsifying salts on casein peptization (dissociation) and apparent viscosity of processed Gouda cheese was studied. Casein peptization was evaluated as peptization coefficient in the final product, while apparent viscosity was determined as flow behavior and consistency indices in the product during processing before cooling. Increasing moisture content and pH of processed cheese samples generally increases peptization coefficient, however the type of emulsifying salt showed to play an important role also. On the contrary, independently of the type of emulsifying salt, predictive regression models were suggested in order to express flow behavior index and consistency index versus chemical composition and pH. Increasing moisture content or reducing pH increases the flow behavior index. Consistency index, and thus the apparent viscosity, of processed cheese samples was increased when the moisture content was reduced, and when pH and the soluble casein content were increased.

Texture evaluation of block-type processed cheese as a function of chemical composition and in relation to its apparent viscosity

“…From the values of pH and moisture content, it is obvious that increasing moisture content of the samples increases their pH. This agrees with the results of Lee et al (2004) and Dimitreli et al (2005).…”

“…This means that when the apparent viscosity of the oil-in-water emulsion of processed cheese during processing is high the textural properties of the resulted three-dimensional matrix after cooling would also have high values. According to our previously published results (Dimitreli & Thomareis, 2004;Dimitreli et al, 2005), moisture content decreases consistency index and thus the apparent viscosity of the processed cheese, while protein content increases it. The moisture and proteins affect the above-mentioned textural properties in the same way.…”

“…The formulations of processed cheese samples are specified in Table 1. The processed cheese samples were manufactured at 80°C as described by Dimitreli and Thomareis (2004) and Dimitreli, Thomareis, and Smith (2005) except for the bigger amount of sample (75 g) that was added to the sample vessel of the tube viscometer. For the experiment, each processed cheese sample was manufactured in triplicate for rheological measurements and also in triplicate for textural evaluation.…”

“…The apparent viscosity of processed cheese samples was determined at 80°C as described by Dimitreli and Thomareis (2004) and Dimitreli et al (2005). The rheological measurements were conducted in triplicate.…”

Potential and restrictions of photocentrifugation for determining the emulsion stability of melted spreadable processed cheese

“…Torque profiles were measured in a farinograph during the manufacture of cheese analogues (El-Bakry et al 2010). Dimitreli et al (2005) and Dimitreli and Thomareis (2008) manufactured PC inside the vessel of a capillary tube viscometer and measured the viscosity before solidification. Lee et al (2003) transferred PC from a lab cooker to a rheometer and analyzed the viscosity profile and microstructural changes.…”