Correct design of the film forming solution has been shown to be a critical factor for the viability of L. rhamnosus GG during the air drying step, room temperature storage and simulated in-vitro digestion. The presence of whey proteins in the film forming solution reduced L. rhamnosus GG viability losses throughout drying and storage and the use of film systems based exclusively on sodium alginate exhibited a very good performance under in-vitro digestion, this is proposed to be due to an ionic setting mechanism.