C. Daporto et al., EFFECTS OF LOW-PRESSURE AND A RECTIFICATION COLUMN ON THE VOLATILE COMPOSITION OF FERMENTED GRAPE DISTILLATE, International journal of food science & technology, 31(5), 1996, pp. 403-410
Fermented crushed Prosecco grapes were distilled using a batch still u
nder normal (100.9 kPa) and reduced pressure (40 or 47 kPa) with and w
ithout the rectifying column of the distillation equipment. To improve
insight into the behaviour of ethanol and the partitioning of some vo
latile compounds, each distillate was collected in fractions and analy
sed for lower volatile alcohols and esters. The results show that the
behaviour of ethanol under reduced pressure was more consistent, the p
roof level higher than at normal pressure and there was a stripping ef
fect on the volatile compounds considered at low pressure. This effect
is enhanced when the rectifying column is included. It was concluded
that it could be advantageous to use 'vacuum distillation' because it
simplifies the operation of the equipment and leads to an overall redu
ction of the heating required, although there are problems of losses o
f desirable aromatic compounds.