Jump to content

ajdelange

Members
  • Posts

    2
  • Joined

  • Last visited

Everything posted by ajdelange

  1. I tried for the first time yesterday to measure the proof on a sample of Limoncelo. Given the sugar content it is obvious that distillation has to be used but I got an unpleasant surprise as soon as water started to come over into the receiver. The distillate turned cloudy. Examination of it under the microscope showed a suspension of tiny globs of oil - lemon oil presumably as the distillate smells deliciously lemony. Obviously, some components of the lemon oil volatilize appreciably at about the same temperatures as ethanol and water. So this oil in the distillate represents an interference. Does anyone have any idea how much it throws readings off (I'm using a DMA 5000M)? Or really, more to the point, how do those of you making Limoncello satisfy TTB wrt proof determination? Thanks. A.J. (new guy here).
  2. "Injection" is best done with a peristaltic pump as this allows one to fill sample into a say a 100 mL volumetric flask (good size for the receiver if you are doing distillation of a liquer, for example) and then do multiple readings on the contents of that flask. It is most important to cover the mouth of the flask (and tubing leading to the analyzer) with parafilm (or something similar) to prevent evaporation. If you don't do this you will notice a monotonic decrease in the alcohol strength readings as ethanol is volatile enough to escape even through the narrow neck of a volumetric flask. And there are no lubricants in the tubing used in a peristaltic pump. [Edit]: Another thing I meant to mention WRT to multiple readings on the same sample: It seems to take a while for a new sample to integrally wet the oscillating U - tube if you have followed A.P's recommendation and dried it between samples. If you haven't it takes a couple of samples to completely rinse the old sample out. In either case you will often notice a fair amount of variance in the early samples (sometimes with a monotonic trend). Eventually, the trend disappears and you get a typical set of "noisy" readings (but the noise is small).
×
×
  • Create New...