Rheological, textural and structural properties of dairy cream as affected by some natural stabilizers

Abstract

The effects of whey protein, basil seed gum (BSG), and κ-carrageenan (CGN) on the structure–rheology interactions of low- and high-fat cream were investigated. Pseudoplastic and thixotropic behavior of cream was found for all the samples and the pseudoplasticity was increased with an increased level of stabilizers. The apparent viscosity (ηa) of the forward curves is greater than that of the backward ones, which may be the result of the breakdown of the fat globule structure under shear stress. The viscosity of cream was reduced, while using a stabilizer (BSG/CGN) can be related to the water binding of hydrocolloid molecules contributing to resistance in flow. For all samples, elastic modulus was greater than viscous modulus, indicating a greater contribution from elastic characteristics. With the increase of BSG/CGN levels, the molecules may be competitively adsorbed onto the surface of fat droplets, thereby changing its surface tension and decreasing its particle size. Increases in whey proteins, fat, and BSG also significantly increased hardness, whereas increases in CGN significantly decreased it. The globular aggregates in the microstructure of high-fat dairy cream were smaller than those in low-fat dairy cream, allowing more water to be retained in the high-fat samples. Therefore, synergistic interactions between polysaccharides and proteins may encourage the formation of a cross-linked network.

Physicochemical and Rheological Characteristics of Fermented Sour Cream (“Suero Costeño”) Produced in Colombia

“…As the shear rate increases, randomly positioned chains of polymer molecules align in the direction of the flow, resulting in less interaction between adjacent polymer chains [30]. Similar results were found in creams with different fermentation levels [3], starch-milk dessert cream [27], low and high fat cream [26], recombined cream [13], sour creams supplemented with milk protein concentrate [5], and whipping cream [31]. In general, dairy cream has shear-thinning behavior (pseudoplastic fluid) due to partially aggregated fat globules, which can be broken down at high shear rates [32].…”

“…These high percentages of thixotropy may be due to the addition of some thickeners or stabilizers [25]. This behavior has been reported for dairy cream with some natural stabilizers [26,27], ice cream [28], and yogurt [29]. Furthermore, for the "sueros costeños" that present time dependence, the ascending curve is greater than the descending curve, so they show a positive thixotropy, where the viscosity decreases with time due to a change of the internal structure when a strain is applied.…”

Impact of Heat Treatment on Consistency Coefficient of Dairy Cream

“…However, no such systematic data is available in the literature. Hence, the study was conducted to assess the effect of varying fat percentages and heat treatments of dairy cream on consistency coefficient [8].…”