Efecto de la adición de transglutaminasa y carragenina en gelles lácteos inducidos por renina.

Abstract

In this paper, transglutaminase enzyme was studied in combination with hydrocolloids (carrageenan, high methoxyl pectin and gelatin) during the enzymatic coagulation of a dairy system, changing the percentage of CaCl2. The purpose was to create a more complex network during the manufacture of dairy gels induced by rennin, and to assess the percentage of protein and fat retained, degree of syneresis, and textural and micro structural properties of the gel. An initial Plackett & Burman experimental design was carried out to understand the interaction between factors modifying the dairy system. Later; some factors were leaked out in order to use them in a new central composite design. During the initial design, we found that CaCl2 and transglutaminase increased the force gradient of dairy gels, while carrageenan decreased the stickiness of them. In addition, the interaction of all the factors showed synergistic attenuation on increasing force gradient as on reducing stickiness. Finally, a 23 central composite design showed that retention of serum proteins and fat in dairy gel could be positively affected by addition of carrageenan and / or calcium into the system, whereas incubation of transglutaminase showed no influence on the retention of them. Moreover, syneresis increased while increasing any factor; however, syneresis could be reduced in contrast with control by using small doses of any ingredient. Firmness, cohesiveness, gumminess and force gradient in dairy gel were favored by increasing carrageenan and calcium, as well as synergistically happened during the interaction of all the factors (in the highest level). By contrast, parameters were decreased sharply during the interaction carrageenan-incubation time (both in high level) when calcium level was low. Moreover, the addition of carrageenan (> 0.037%) or incubation time (<60min) increased the elasticity of the gel, and a faster recovery of the sample after deformation (resilience) occurred by adding calcium or carrageenan. While adhesiveness and stickiness decreased by increasing calcium, interacting time of incubation with calcium or adding carrageenan to the system while calcium is in the lowest level. In contrast we observed an increase in both parameters when carrageenan and calcium where in the highest level, and also during the interaction of all the factors (all high). Finally, the interaction between homogeneous (with carrageenan) and porous (transglutaminase) microstructure resulted in a similar texture to the control.