Microencapsulation of Porcine Liver Hydrolysate by Spray Drying and Freeze-Drying with Different Carrier Agents

This research aimed to microencapsulate porcine liver hydrolysate using different coat materials (arabic gum, maltodextrin, whey protein, a combination of whey protein with maltodextrin, xanthan gum, and soy protein isolate) by two different encapsulating methods (spray drying and freeze-drying) to obtain capsules with controlled release and resistant to the passage through the gastrointestinal tract. The thermogravimetric analysis of the microcapsules evidenced good thermal stability. All microparticles presented low water activity, being considered biologically and biochemically stable. In the gastrointestinal simulation, the antioxidant activity was evaluated, and all the coat materials were adequate to protect the biopeptides against gastrointestinal conditions, except for xanthan gum, which presented low efficiency. The antimicrobial activity was also evaluated in the in vitro digestion for 4 h, the microcapsules produced with Gum Arabic, Soy Protein Isolate and Whey+Malto (only those produced in a lyophilizer) showed an inhibitory action against Candida albicans and the microcapsules produced with Whey Protein, Whey+Malto and Soy Protein Isolate (only those produced in spray drying) showed inhibition for Staphylococcus aureus. The results obtained for gastrointestinal simulation demonstrated that microencapsulation preserved the antioxidant and antimicrobial activity of the pork liver hydrolyzate, confirming its importance for the maintenance of biopeptides.