Evaluation of the Physicochemical Characteristics of a Blend Fruit Juice Powder Mixed with Lactiplantibacillus plantarum: A Comparison of Spray Drying and Freeze Drying

Abstract

The physicochemical properties and the survival of Lactiplantibacillus plantarum mixed with blend of fruit juice powders dried by spray and freeze drying methods were investigated. A formula containing maltodextrin 14% and malt extract 6% as a carrier and juices of red grape 20.4%, mulberry 75.6%, and strawberry 4.0% along with the bacterium (Lpb. plantarum) with $3\times {10}^9$  CFU/mL were dried by spray drying and freeze drying methods, separately. The physicochemical properties including color attribute, nutritional properties of the powders such as antioxidant, and phenolic content were measured. Drying efficiency of freeze-dried was 80.48%, which was higher than the spray-dried powders (50.84%). The higher antioxidant (87.95) and total phenolic content (3032.6 mg GAE/L) was achieved by freeze drying technique; however, lower moisture content and flowability as well as higher solubility and bulk density were obtained for spray-dried powders. The survival of probiotics in freeze-dried powders was higher than the spray-dried powders which can be related to mild conditions. The study indicated that the juice powders are suitable carriers for Lpb. plantarum and constitute good alternatives to highly acidic fruit juices.