Scott Labs Malolactic Bacteria and Nutrient Choosing Guide
Last Updated: 7/2021
Applies to: Winemakers looking for assistance in selecting and comparing Scott Labs malolactic bacteria and nutrients. This guide contains a downloadable pdf choosing chart with information on each bacteria strain and nutrient offered.Download
Selecting Bacteria for Success
It is very important to know the properties of the wine prior to inoculating with malolactic bacteria. Analyze the wine for pH, SO2, volatile acidity (VA), residual sugar, malic acid and alcohol. Extremes in one or more of these properties can have a compounding inhibitory effect on the growth of malolactic bacteria. For example, if a wine has low pH and high SO2, that will be more antagonistic to the bacteria than low pH alone. Creating an optimal environment for malolactic bacteria includes:
Malolactic bacteria require sugar (fructose, glucose), organic acids (malic, citric, pyruvic), organic nitrogen (amino acids, peptides), vitamins (B group, pantothenic acid) and trace minerals (Mn, Mg, K, Na). Good nutrition is important for malolactic bacteria and nutrients such as OPTI'MALO BLANC™ and ML RED BOOST™ will help with the growth and survival of specific malolactic bacteria. Malolactic nutrients are not as critical in a co-inoculation with yeast.
Volatile Acidity (VA)
Wines may have elevated VA due to high pH which allows other strains of bacteria to grow. The wine should be monitored for unwanted bacteria.
Choose a yeast strain which is compatible with the selected malolactic bacteria. See MLF Compatibility in the yeast charts in the Scott Labs Yeast Choosing Guide.
Malic and Lactic Acid
Measure malic acid levels. Wine conditions are difficult for bacteria if the malic level is <0.5 g/L or >7.0 g/L. The higher the malic acid levels the higher the resulting lactic acid levels. This can be stressful for bacteria. Lactic acid levels of 1.5 g/L slow down bacteria and 3 g/L starts to inhibit MLF.