Effect of sodium hexametaphosphate concentration and cooking time on the physicochemical properties of pasteurized process cheese

Abstract

Sodium hexametaphosphate (SHMP) is commonly used as an emulsifying salt (ES) in process cheese, although rarely as the sole ES. It appears that no published studies exist on the effect of SHMP concentration on the properties of process cheese when pH is kept constant; pH is well known to affect process cheese functionality. The detailed interactions between the added phosphate, casein (CN), and indigenous Ca phosphate are poorly understood. We studied the effect of the concentration of SHMP (0.25-2.75%) and holding time (0-20min) on the textural and rheological properties of pasteurized process Cheddar cheese using a central composite rotatable design. All cheeses were adjusted to pH 5.6. The meltability of process cheese (as indicated by the decrease in loss tangent parameter from small amplitude oscillatory rheology, degree of flow, and melt area from the Schreiber test) decreased with an increase in the concentration of SHMP. Holding time also led to a slight reduction in meltability. Hardness of process cheese increased as the concentration of SHMP increased. Acid-base titration curves indicated that the buffering peak at pH 4.8, which is attributable to residual colloidal Ca phosphate, was shifted to lower pH values with increasing concentration of SHMP. The insoluble Ca and total and insoluble P contents increased as concentration of SHMP increased. The proportion of insoluble P as a percentage of total (indigenous and added) P decreased with an increase in ES concentration because of some of the (added) SHMP formed soluble salts. The results of this study suggest that SHMP chelated the residual colloidal Ca phosphate content and dispersed CN; the newly formed Ca-phosphate complex remained trapped within the process cheese matrix, probably by cross-linking CN. Increasing the concentration of SHMP helped to improve fat emulsification and CN dispersion during cooking, both of which probably helped to reinforce the structure of process cheese.

The effect of ternary emulsifying salt composition and cheese maturity on the textural properties of processed cheese

“…A possible explanation could lie in the ability of polyphosphates to give multiple negative charges to the caseins present. Attractive hydrophobic interactions between caseins are reduced in systems with more negatively charged caseins (Mizuno & Lucey, 2007;Shirashoji et al, 2010). The effect of a specific ratio of DSP to TSPP is reduced and disappears with increasing relative content of POLY above 60%.…”

“…A higher degree of casein dispersion probably enhances the capability of caseins to bind water and emulsify the fat present; the latter processes increase the intensity of interactions in the melt. The higher the presence of crosslinkages in the matrix of the product, the harder the processed cheese that can be expected (El-Bakry et al, 2011;Kaliappan & Lucey, 2011;Mizuno & Lucey, 2005a, 2005bShirashoji, Jaeggi, & Lucey, 2010). …”

“…There was no change in the trends concerning the dependence of texture parameters of the processed cheeses on the composition of emulsifying salts. According to Awad et al (2002), Guinee et al (2004), Shirashoji et al (2010) and , the increase in hardness can be attributed mainly to the hydrolysis of phosphate salts (with two or more phosphorus atoms in a molecule) and also to possible changes in the forms of binding of the salts present and thus a change in their dissociative characteristics. The latter processes might also be related to the intensity of water-binding in the casein network.…”

The effect of individual phosphate emulsifying salts and their selected binary mixtures on hardness of processed cheese spreads

“…and non-dairy ingredients and additives (hydrocolloids, colouring, sensory active mixtures etc.) could be used during processed cheese production (Carić & Kaláb, 1997; Lee et al, 2004;Shirashoji et al, 2010). The production of processed cheese is composed of this six steps: i) ingredients formation (with respect to the desired parameters of the final product) ii) ingredients cleaning, milling and cutting iii) blending all ingredients in melting device iv) the melting process (melting temperature between 85-105 °C with a dwell time of several minutes) v) packaging vi) cooling and storing (Kapoor & Metzger, 2008).…”

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

“…Uniaxial compression and texture profile analysis were applied after manufacturing, usually at 15-20°C (Weiserová et al 2011;Bunka et al 2014;Nagyová et al 2014;Hladká et al 2014). A temperature sweep in a rheometer covered 20 to 90°C and was performed at low frequency and deformation (Shirashoji et al 2010;Guinee and O'Kennedy 2012;Schatz et al 2014).…”