C A T A L O G U E e n o l o g i c a l p r o d u c t s

ADVICE FOR COLOR STABILIZATION WHEN USING
YEAST/BACTERIA CO-INOCULATION
Yeast/bacteria co-inoculation practices give wines that have less color than those that are
fermented in a traditional manner. This happens because the interval between the end of alcoholic
fermentation and the start of malolactic fermentation, is lost. During this interval there are favorable
conditions for anthocyanin/tannin compounds to form through ethanal bridge condensation.
Therefore, when using co-inoculation practices, it is essential to support color stabilization during
alcoholic fermentation.
STAGE WHAT TO DO HOW
HARVEST/GRAPE
RECEPTION
MACERATION
YEAST
INOCULATION
BACTERIA
INOCULATION
ALCOHOLIC
FERMENTATION
MALOLACTIC
FERMENTATION END
As soon as the crush begins, add sulfites to prevent the development
of undesirable microorganisms and the oxidation
of colorant substances.
The use of a blended antioxidant/antimicrobial substance,
reduces the amount of sulfur dioxide needed, and hence
facilitates the malolactic fermentation process.
The low temperatures needed for co-inoculation slows down
and reduces grape tannin extraction which is fundamental
for anthocyanin condensation.
Using maceration enzymes increases tannin extraction and
favors stable color compound formation.
For a proper co-inoculation, it is essential to choose a yeast
strain that does not hinder the bacteria development and
also that has a medium lag phase so as to favor bacteria
development.
It is very important to pay attention to yeast nutrition: every
nutritional deficiency leads to an accumulation of toxic substances
that can then lead to problems which can inhibit
the start of malolactic fermentation. The use of yeast derivative-based
nutrients provides all the necessary nutritional
factors. Furthermore, supplying available nitrogen helps both
yeast and bacteria in their respective fermentations.
Mannoprotein supply beginning in the first maceration phases
encourages the formation of anthocyanin/mannoprotein
color complexes that are resistant to oxidation. Furthermore,
mannoproteins decrease the “bacteriostatic” effect of
tannins and favor the development of the bacteria that are
successively inoculated.
The supply of grape tannins during the maceration phase
without alcohol, favors anthocyanin condensation and the
consequent formation of a stable color.
24 hours after yeast inoculation, it is possible to inoculate the
malolactic bacteria.
Keep the temperature between 16 and 25 °C to ensure
bacteria survival.
Constantly monitor the alcoholic fermentation progress.
To ensure a stable and complete alcoholic fermentation,
at 1/3 of sugar depletion it is essential to supply all the nutritional
elements that yeast need in this difficult phase:
nitrogen, oxygen and survival factors.
12-24 hours after bacteria inoculation up until the fermentation
end it is possible to intervene with the addition of
tannins to contribute to copigment formation in order to
increase color stability and intensity in the wine.
At the end of malolactic fermentation, rack-off and proceed
with a short macro-oxygenation to maximize the
formation of stable color components from the free anthocyanins
still present in the wine.
100-200 g/ton AST
30-40 g/ton
ENARTIS ZYM COLOR PLUS
200-300 g/ton
ENARTIS FERM RED FRUIT
or ES 454 or ES 488
300 g/ton
NUTRIFERM AROM PLUS
300 g/ton
ENARTIS PRO TINTO
ENARTIS ML SILVER
300 g/ton
NUTRIFERM ADVANCE +
10-15 mg/L of oxygen
150-200 g/ton
ENARTIS TAN XC
10-15 g/hL ENARTIS TAN
μICROX or TAN MICROFRUIT +
1-3 mg/L/day of oxygen
for 3-4 day*
*macro-oxygenation dosages and duration must be chosen according to the wine turbidity
and structure.