Influence of gelatin/guar gum mixture on the rheological and textural properties of restructured ricotta cheese

Abstract

In order to get insights on the effect of temperature (25-60 °C) and selected hydrocolloids (gelatin and guar gum) on the ricotta cheese, the physicochemical, appearance, textural, and rheological properties of this dairy product were studied. The chemical properties influenced on the textural and rheological properties, in which the lower value of cohesiveness attributed to the low fat/protein ratio in ricotta cheese. Increasing the temperature from 25 to 60°C, the elastic, viscous, and complex moduli were decreased, which is the against of the rheological properties of heat-sensitive cheeses. Gelatin/guar gum inclusion to the ricotta cheese did not increase the structural strength (G'), and the utmost G' was obtained in lack of carbohydrates. Although, the highest fracture/yield stress was obtained for gelatin 4%-guar gum 1%, the high elastic modulus was achieved at gelatin 5%-guar gum 0.5%. Mechanical spectra of the ricotta gels elucidated shear-thinning behavior with a highly interconnected elastic gel structure (G'>G", n ∼ 0.20). Consequently, it can be ascribed the elastic modulus lonely is insufficient to characterize gel systems without obtaining yield and fracture properties. The findings confirmed that the gelatin/guar gum inclusion did not develop a strong ricotta gel.