Antonio, ALFONZO1, Rosario, PRESTIANNI1, Antonio, ALFONZO1, Michele, MATRAXIA1, Valentina, CRAPARO1, Vincenzo, NASELLI1, Paola VAGNOLI2,
Sibylle KRIEGER-WEBER3, Giancarlo, MOSCHETTI1, Luca, SETTANNI1, Raimondo, GAGLIO1, Antonella, MAGGIO4, Nicola, FRANCESCA1
1 Department of Agricultural, Food and Forestry Science, University of Palermo, Viale delle Scienze 4, 90128 Palermo, Italy
2 Lallemand Italia,VR, Italy
3 Lallemand S.A., Korntal-Mu¨nchigen, Germany.
4 Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Italy
Email contact: antonio.alfonzo[@]unipa.it
AIM: Lactiplantibacillus plantarum and Oenococcus oeni species is worldwide used as starter for malolactic fermentation [1, 2]. For the first time, in the present study, the impact of malolactic fermentation on Sicilian white wines of the Catarratto cultivar was evaluated by using different commercial LAB strains. Particularly, L. plantarum (ML PrimeTM, Lallemand wine), O. oeni (Lalvin VP41®, O-Mega® and PN4®, Lallemand wine) were used as starter strains for malolactic fermentation.
METHODS: the Catarratto must, after clarification, were aliquoted in steel tanks (2.5 hL). Each tank (5 trials: M8-M12) was inoculated with the indigenous selected strain CS182 Saccharomyces cerevisiae. After 24 hours, ML PrimeTM (M8) , Lalvin VP41® (M9), O-Mega® (M10) and PN4® (M11) were inoculated singularly into grape must. For the control trial, were not added with malolactic starter (M12-MLc). During the alcoholic fermentation, the microbiological and chemical-physical parameters were evaluated. After six months from the date of bottling, the wines were subjected to volatile organic compound investigation and sensory analysis.
RESULTS: grape must showed values of malic acid of 1.58 g/l. Trial M8 inoculated with L. plantarum showed a significant reduction of malic acid reaching values of 1 g/L, three days after inoculum. Trial M9, M10 and M11, inoculated with O. oeni, showed a rapid consumption of malic acid after 15 days of AF and completed malolactic fermentation one week after AF.
The VOCs present in highest concentration were 3-methyl-1-butanol in all trials, phenylethyl alcohol in trials M8, M9, and M12, and 2,3-butanediol in M11.
The sensorial analysis conducted on the different experimental wines showed a tendency of panelists to prefer trials M8. In fact, wines with the addition of MLPrimeTM, obtained the highest scores for the attributes flavor and odour overall quality, intensity and complexity odours. No unpleasant odours and/or flavours were recorded. Acetic acid content was less than 0.3 g/l in all experimental trials.
CONCLUSIONS: The inoculation of the different commercial LAB strains allowed the malo-lactic fermentation of all wines. L. plantarum proved to be an effective alternative to O. oeni in order to start the malolactic fermentation and the wines were appreciated at sensorial level.