The percentage of color derived from
the monomeric pigments was greater in
the fruit than the wine, while the percentage
of color frompolymeric pigment
forms showed the opposite trend.
Merlot délestage and control wines
showed slight differences in the percentage
of color from the different pigment
sources. Délestage wines produced
over three seasons averaged
4.8% lower color derived from monomeric
pigments, 1.4% higher from SPP,
and 4.5% higher color from LPP, compared
to control wines (Figure II).
Following fermentation, control
and délestage-produced Merlot wines
did not differ in alcohol percent (v/v),
TA, tartaric, malic, and lactic acids, or
pH (Table I).
The total tannin concentration was
greater in the control wines upon completion
of fermentation each year. The
total phenol estimations demonstrated
a higher concentration in control wines
in two of the three years. Total anthocyanins
were higher in the control
wines in the two years measured,
while absorbance at 420 nm + 540 nm,
and 420 nm/520 nm, did not demonstrate
consistent patterns between
délestage and control wines.
Table II provides the concentration
of selected phenolic compounds on
aged Merlot determined by HPLC
analysis. Significant differences among
treatments were not observed.
Catechin and epicatechin concentrations
averaged 37 and 26 mg/L for the
control and délestage-produced wines,
respectively.
Merlot total glycosides increased by
day-two, the first day of fermentation
(Table III). By the completion of fermentation
(dejuicing), the total glycoside
concentration had increased by an
average of 388% and 296% for the control
and délestage wines, respectively.
