TEXTURAL AND MICROSTRUCTURAL CHARACTERIZATION OF KEFIR-BASED CREAM CHEESES ENRICHED WITH DIFFERENT TEXTURIZING FIBERS

Kefir consists of a symbiotic association of lactic acid bacteria (LAB), acetic acid, and yeast in a polysaccharide and protein matrix. Food fibers with prebiotic value can be used in several dairy products to optimize their functional and technological properties. Therefore, the respective work aimed to formulate kefir-based cream cheeses with 1% of different prebiotic fibers (Fructo-oligosaccharides - FOS, Xylo-oligosaccharides - XOS, and Inulin) and to characterize the products in terms of their textural and microstructural profile. The determination of the cheese texture profile was performed using a Texturometer and the data were collected by the Software Texture Exponent 32 (Stable Micro Systems), evaluating the parameters of gumminess, cohesiveness, adhesiveness, and hardness. For the analysis of the microstructure of the clot formed, Scanning Electron Cryo-microscopy (Cryo-SEM) was used. The results showed that over the storage period (14 days), the addition of FOS provided an increase in gumminess, adhesiveness, and hardness, however, reduced cohesiveness. The addition of XOS and inulin, on the other hand, caused the reduction of all evaluated textural parameters. The treatment without adding fiber showed an increase in gumminess and hardness and a slight reduction in adhesiveness and cohesiveness. The reduction in the cohesiveness of all treatments can be caused by the increase in the acidity of the product. Scanning microscopy images explained the texture analysis results, proving that the presence of prebiotic fibers disrupts casein networks, resulting in a slight effect on texture, appearing in the form of porosities. While the control treatment, which consists of the absence of fiber, has a more compact structure with smaller gaps. Therefore, prebiotic fibers can help improve the texture parameters of the product. Inulin, Xylo-oligosaccharides, and Fructo-oligosaccharides proved to be interesting technological alternatives for the manufacture of creamy cheeses based on Kefir.