DESENVOLVIMENTO E CARACTERIZAÇÃO FÍSICO ... - UFSM

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activated by acyl-S-CoA (RAAP & GUNTERT, 1986). The main ester of in jelly palm wine is a
straight-chain ethyl hexanoate. It was described as the major volatile compound in jelly palm fruit
by Ferrão (2012) and had its aroma described by Bernardi et al., (2013) as the same aroma as jelly
palm fruit. Under the applied treatments the concentration of ethyl hexanoate was lower in the
fermentations at 10 ºC and less days of maceration differing statistically from the treatments at 20
ºC. Besides ethyl hexanoate, the effect of maceration time and temperature were similar for the
others esters present in the wine. According to Killian and Ough, (1979), low fermentation
temperatures (10 ºC) favor the synthesis if fruit esters such as those cited above while high
temperature of fermentation (20 ºC) promotes the production of high molecular height esters. The
treatment M7T20 showed the highest concentration for the esters differing statistically from the
treatment D2T10.
Ethyl acetate was reported in lower concentration in pineapple wine (38.3 µg/l), raspberry
wine (7.9 µg/l) and cacao wine (0.19 µg/l) and the fermentation temperature for those wines ranged
between 22 to 26 ºC (DUARTE et al., 2010a; PINO & QUERIS, 2010). However ethyl acetate
formation is a common microbial fault produced by wine spoilage yeasts and it may be also formed
in wine by a chemical interaction between ethanol and acetic acid (JACKSON, 2000). Therefore
wines with high acetic acid levels are more likely to see ethyl acetate formation. According to
Suomaleinen, (1981), an increase in the fermentation temperature releases higher levels of esters
through more efficient excretion and/or enhanced autolysis of the yeast. An effect of the
temperature on the thermodynamic equilibrium of ester solubility in cellular lipids and the aqueous
medium is another possibly more likely explanation. Selli et al., (2006) has showed that, increasing
the maceration time the concentrations of several esters increased significantly while Torija et al.,
(2003) has reported that at lower temperatures (10-15 ºC) the concentration of volatile compounds,
such as, esters increase. In jelly palm wine, esters were found in high concentration for the
treatments fermented at 20 ºC and with 7 days of maceration.
3.4 Acids
Maceration time and fermentation temperature have a straight relation with acids
concentration in wine. In general, in a traditional fermentation fatty acid concentrations increase
in prolonged maceration time and high temperatures (RODRÍGUEZ-BENCOMO et al., 2008;