Wine Analysis

Suck Back during Alcohol Determination by Distillation

• When removing the heat source from the boiling flask, before opening the closed system, the lowered pressure created by the condensation of steam above the boiling flask, can suck the contents of the volumetric flask back into the condenser or worse still into the boiling flask.
  
  
• If you forget to apply the above method and observe the rising, collected distillate; break the sealed system before any distillate reaches the top of the condenser, by either lowering the volumetic flask or separating any of the joints above the condenser.
  
  Then all that is required is for you to rinse the condenser and receiver adaptor attached with distilled water using a squeeze bottle, into the volumetric flask, making sure not to fill the volumetric flask past its graduation mark.
  
  
• If you are not sure whether any of the distillate has returned to the boiling flask start again.
  
  An uncertain result is no result at all.