Nicola, FRANCESCA1, Antonio, ALFONZO1, Rosario, PRESTIANNI1, Michele, MATRAXIA1,Valentina, CRAPARO1, Vincenzo, NASELLI1, Paola VAGNOLI2, Sibylle KRIEGER-WEBER3, Giancarlo, MOSCHETTI1, Luca, SETTANNI1, Raimondo, GAGLIO1, Antonella, MAGGIO4
1 Department of Agricultural, Food and Forestry Science, University of 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: nicola.francesca[@]unipa.it
AIM: Lactiplantibacillus plantarum species is wordwide used as starter for malolactic fermentation [1,2]. For the first time, in the present study, the use of L. plantarum (ML PrimeTM, Lallemand wine) to produce white wines with post-fermentative maceration extended until 60 days has been investigated.
METHODS: unpressed grapes of Catarratto cultivar were inoculated with the indigenous selected strain CS182 Saccharomyces cerevisiae . After 24 hours, ML PrimeTM was inoculated into grape must. For the control trials, malolactic fermentation occurred spontaneously. During the alcoholic fermentation the microbiological and chemical-physical parameters were evaluated. After 60 days of post-fermentation maceration, the wines transferred into steel tanks and subjected to volatile organic compound investigation and sensory analysis.
RESULTS: grape must showed values of malic acid of 1.90 g/L. Interestingly, 24 hours after inoculation of ML PrimeTM, malic acid was totally converted into lactic acid that reached values of 1.54 g/l. Spontaneous malolactic fermentation started one month later the end of alcoholic fermentation. Experimental wines subjected to malolactic fermentation with ML PrimeTM showed a reduction of acid and bitter taste and were characterized by intense creamy and freshness both at smell and taste. Acetic acid contents was lower than 0.3 g/L in all experimental trials.
CONCLUSIONS: inoculation of the ML PrimeTM before the addition of starter yeast into unpressed grape must allowed malolactic fermentation within 24-48h at 18°C. ML PrimeTM is an effective alternative to Oenococcus oeni to undertake malolactic fermentation in white wines subjected at long post-fermentative maceration.