title: Impact of different spray-drying conditions on the viability of wine Saccharomyces cerevisiae strains.
abstract: Spray-drying (SD) is widely considered a suitable method to preserve microorganisms, but data regarding yeasts are still scanty. In this study, the effect of growing media, process variables and carriers over viability of a wild wine Saccharomyces (S.) cerevisiae LM52 was evaluated. For biomass production, the strain was grown (batch and fed-batch fermentation) in a synthetic, as well as in a beet sugar molasses based-medium. Drying of cells resuspended in several combinations of soluble starch and maltose was performed at different inlet and outlet temperatures. Under the best conditions-suspension in soluble starch plus maltose couplet to inlet and outlet temperatures of 110 and 55 °C, respectively-the loss of viability of S. cerevisiae LM52 was 0.8 ± 0.1 and 0.5 ± 0.2 Log c.f.u. g(-1) for synthetic and molasses-based medium, respectively. Similar results were obtained when S. cerevisiae strains Zymoflore F15 and EC1118, isolated from commercial active dry yeast (ADY), were tested. Moreover, powders retained a high vitality and showed good fermentation performances up to 6 month of storage, at both 4 and -20 °C. Finally, fermentation performances of different kinds of dried formulates (SD and ADY) compared with fresh cultures did not show significant differences. The procedure proposed allowed a small-scale production of yeast in continuous operation with relatively simple equipment, and may thus represent a rapid response-on-demand for the production of autochthonous yeasts for local wine-making.
authors.affiliation: Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Via Università 100, 80055, Portici, NA, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Aponte
authors.affiliation: Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Via Università 100, 80055, Portici, NA, Italy.
authors.forename: Gabriele Danilo
authors.initials: GD
authors.lastname: Troianiello
authors.affiliation: Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Via Università 100, 80055, Portici, NA, Italy.
authors.forename: Marika
authors.initials: M
authors.lastname: Di Capua
authors.affiliation: Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Via Università 100, 80055, Portici, NA, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Romano
authors.affiliation: Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Via Università 100, 80055, Portici, NA, Italy. blaiotta@unina.it.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Blaiotta
mesh_terms: D061249:Batch Cell Culture Techniques; D018533:Biomass; D015169:Colony Count, Microbial / Q000379:methods; D003470:Culture Media; D003890:Desiccation / Q000379:methods*; D005285:Fermentation; D005516:Food Microbiology; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D050296:Microbial Viability; D008965:Molasses; D011309:Preservation, Biological; D012441:Saccharomyces cerevisiae / Q000254:growth & development*; D014920:Wine / Q000382:microbiology*
chemical_list: D003470:Culture Media
keywords: Autochthonous wine yeast; Fermentative capacity; Formulation; Saccharomyces cerevisiae; Spray-drying