Anais do Simpósio Latino Americano de Ciências de Alimentos
Anais do 14 SLACA - Simpósio Latino Americano de Ciência de Alimentos

The growing consumption of functional food has impacted on research for development of innovative products with beneficial health properties, such as beverages fermented with probiotic microorganisms. The immobilization of microorganisms for application in fermentation processes can be an interesting tool to improve the microbial viability, and the study of alternative immobilization carriers is important to reduce production costs. The objective of this work was to immobilize two probiotic bacteria in wheat bran and apply in fermentation of apple juice. Additionally, the microbial viability (during fermentation and storage) and the antioxidant properties of the fermented product were investigated. Lactobacillus casei (CCT 3750) and Lactobacillus plantarum (CCT 0580) were used in the following conditions: 0.1 g of each bacteria was mixed in 1 g of wheat bran and 40 mL of MRS broth and incubated for immobilization. In the immobilized complex was added 50 mL of apple juice for fermentation during 8 h at 35°C under agitation of 50 rpm. Samples were collected at 0 and 8 h for pH analysis and lactic bacteria enumeration by drop plate method. For measurement of antioxidant properties using ABTS- and DPPH- radicals scavenging activities, the samples were collected at 0, 2, 4, 6 and 8 h fermentation. During fermentation there was no significant reduction in pH (from 3.81 to 3.79). The quantification of lactic acid bacteria indicated the maintenance of viable cell counts around 10^8 CFU/mL during fermentation and after 35 days of refrigerated storage. The highest results for antioxidant activity were detected in the sample produced after 2 h fermentation for DPPH and ABTS, reaching 22.86 and 29.71 μmol TE/100 mL, respectively. These results showed that during fermentation there was production of compounds that increase the antioxidant activity of the juice and that immobilization was an efficient strategy to maintain cell viability throughout storage.