Scientific Papers Series B Horticulture

wine of Merlot type, the characteristics ofwhich are shown in table 1.Figure 2. Lactic bacteria number evolution in the winesinoculated with 10% wine-yeasts in full MLFTable 1. The phisico-chemical and microbiologicalcharacteristics of the malolactic fermented MerlotTypeof wineMerlotWine characteristicsAlcohol% vol 11.7Sugars g/l 5.4Tot. ac. g/l H2SO4 4.20Volatile acidity g/l CH3COOH 0.38total 28.2 SO2free 0.0pH 3.30Bacteria no./mm 3 7.0x10 4From the table 1, we can show that at the endof metabolized period of malic acid, the bacterialdensity was 7,0x10 4 cells/mm 3 . In table 2,are shown the results of the microbiologicaltests, content of anthocyans and total polyphenolsin the concentrate bacterial and in thefiltrate obtained.The lactic bacteria number from the concentratebacterial was 2,1x10 6 cells/mm 3 , while thefiltrate was sterile. The content of anthocyansand total polyphenols were greater values in thefiltrate than in the concentrate bacterial.Table 2. The microbiological and phisico-chemicalcharacteristics of the concentrate bacterial and the filtrateobtained from Merlot wineNumberof lacticbacteria/mm 3Anthocianins mg/lPFTg/lConcentratebacterial2.1x 10 6 210.1 1850Filtrate 0 320.0 1990IV. In our researchs, we selected 10 strains oflactic bacteria from young red wines (Pinotnoir, Merlot, Cabernet sauvignon, Feteascaneagra, Blawer). In the selection process werehad in view criteria that they must have,namely: to possess the capability to increase atlow pH, to grow in the presence of alcohol, toproduce low amounts of volatile acids, do notdegrade certain compounds in wine, as pentoze,glycerol, tartaric acid, etc. Of the 10 strainsisolated by us were tested morphologically,physiologically and oenological point of view,it noticed that strains registered with code 1, 2,5, 7, belonging to the species Leuconostocoenos, the codes 3 and 6 the species Leuconostocgracile, and the codes 4, 8 and 10, toPediococcus cerevisiae species. For verificationin production conditions were chosen strains 1,2 and 5 of the species Leuconostoc oenos. Inour experiments, the starting of malolacticfermentation took place when the amount ofinoculum was 2.5x10 4 cells/mm 3 on conditionthat at least 1.2×10 4 cells/mm can formcolonies. After inoculation of lactic bacteria inthe wine, the bacteria passed through anadaptation period because their function waslimited by the alcohol content and pH of thewine. Three selected bacteria strains verified inwines, has realised the malic acid degradationin 5-7 days. Volatile acidity of the wines havehad different growing-up, the smaller was inthe sample inoculated with the strain code 2(0.08 g/l CH 3 COOH), and the biggest at thesample inoculated with strain code 1 (0.16 g/lCH 3 COOH) (Table 3).Table 3. The changes in the wine composition, inoculated with different bacteria strains after malolactic fermentationFree SO The strain code2 Acetaldehyde Totale acidity Vol acidity g/l Increase of vol.pHmg/l mg/l g/l H 2 SO 4CH 3 COOH acidity with:Initial wine 12,2 16,1 4,00 3,60 0,34 -Malolactic bacteria Code 1 10,5 12,6 3,42 3,67 0,50 0,16Malolactic bacteria Code 2 10,5 15,8 3,20 3,59 0,42 0,08Malolactic bacteria Code 5 11,1 29,9 3,30 3,70 3,45 0,1121