Wine Analysis

Recommended method of aspiration

• It is highly recommended that the aspiration be achieved by applying a vacuum rather than pressure (see fig 6 & see fig 7 respectively)
  
  
• By applying a vacuum to draw air through the SO₂ apparatus, means any leaks will only result in extra air being drawn into the system without any interfering consequences.
  
  
• However, if the SO₂ apparatus has any leaks, using pressure will blow any liberated SO₂ out of the system before it reacts with the hydrogen peroxide (H₂O₂ ).
  
  This will result in low, false SO₂ readings.
  
  
• Applying a vacuum, as shown, reduces the likehood of the manometer stopper being blown out if pressure were to be applied.