Lactobacillus vini

Genus/species: Lactobacillus vini


Gram Stain: Positive


Morphology: 
Cell: Rods; 0.49-0.82 micro meters x 1.36-2.8 micro meters; single cells or they grow in short chains (chain formation depends on the pH of the medium and growth stage of the microorganisms);
Colony:0.7–1.5 mm in diameter, with entire edges, smooth, glistening and white (Rodas et al).
Liquid Growth: likely dispersed.


Physiological Traits:

  • Needs a wide variety of nutrients and supplements in order to grow; requires complex medium with amino acids, peptides, nucleic acid derivatives, vitamins, salts, fatty acids, fatty acids esters, fermentable carbohydrates
  • Optimal growth temperature is between 20 and 37 °C (able to grow in the range between 15 and 45 °C)
  • Facultatively anaerobic microorganism
  • pH between 5.5 and 6.2 for optimal growth.


Ecological Traits: 
Isolated form many places in nature: on grapes, grape leaves, in grape must, vegetables, water, silage, milk, soil.


Distinguishing Features:

  • Able to ferment pentoses homofermentatively
  • No gas is produced form glucose
  • Isomeric form of the lactate that is produced
  • No fermentation of gluconate, mannitol, melibiose, raffinose, and sorbitrol
  • Catalase negative


Role in wine
:

  • Normal grape/fermentation flora.
  • Due to the production of different chemical compounds (acetic acid, diacetyl, acetoin, 2,3- butandiol, ethyl lactate, diethyl succinate and acrolein) it can influence the flavor of wine.


Sensitivities:

  • SO2:
  • Sorbate: No inhibition by sorbate levels up to 1000 ppm.
  • DMDC:
  • pH: greater than 7.2
  • Acids:
  • Ethanol: Lactobacillus viniis able to survive alcoholic fermentation
  • Anaerobiosis:
  • Heat: can’t tolerate temperatures above 53 °C