Desenvolvimento de queijo tipo reino adicionado de Lb. acidophilus (LA-3) microencapsulado

Abstract

Cheeses like Reino type can be excellent vehicles for probiotic cultures. The microencapsulation of probiotics confers additional protection to the microorganism, facilitating its survival in cheese, as well as exerts a barrier function, not allowing the interaction with cheese components, in order not to mischaracterize it. The addition of substances, such as L-cysteine hydrochloride and ascorbic acid, associated with biopolymers in microencapsulation, may favor the maintenance of probiotic viability in the microparticles. This research had as main goal the development of formulations of Reino cheese containing or not the probiotic free or microencapsulated Lb. acidophilus in order to obtain a product with functional potential. Microparticles of Lb. acidophilus were developed using ionic gelation technology with sodium alginate added by L-cysteine hydrochloride and/or ascorbic acid in order to promote the survival of the added lactic acid bacteria. Microparticles were characterized according of morphology; distribution and size of the microparticles and shelf life monitoring (60 days). Three cheese formulations were developed, one without addition of Lb. acidophilus (T1 - control), others containing free probiotic (T2) or present one via microparticles (T3). The cheeses were analyzed immediately after manufacture and after 25 days of maturation, regarding the microbiological parameters of quality control and the survival percentage of Lactobacillus spp. The physical-chemical parameters analyzed in the cheese formulations were pH, titratable acidity, Aw, fat content, protein content, moisture, ash, indices of extent and depth of proteolysis and texture profile. Microparticles had a mean diameter of 58 ± 1.51 μm, spherical, smooth and uniform shape. The added cheese of Lb. acidophilus in the free form (T2) presented viability of total lactobacilli lower (7.3 ± 0.05 Log CFU/ g) compared to the control (7.9 ± 0.03 Log CFU/ g) after the maturation period. However, the added formulation of the microparticles presented above 8 Log CFU/ g, evidencing maintenance of the microorganism. Significant differences (p <0.05) in pH, acidity, protein, moisture, ash and total dry matter parameters were observed when compared to control (T1). The control cheese presented higher values for most of the texture parameters compared to the cheeses added with probiotics. In addition, the positive effect in this aspect for Reino cheeses added of probiotics is observed, due to the significant decrease in hardness and chewiness during maturation. In addition, the added cheese of microparticles (T3) has become viable, since it provides additional protection to the microorganism Lb. acidophilus benefiting microbial cell survival, with an improvement in texture characteristics and, therefore, resulting in a potential functional Reino cheese.