Expectorating is polite term for spitting something out. It is not uncommon for cuppers to be required to taste over 100 samples per day. This level of exposure to caffeine makes its essential that cuppers make their evaluations without swallowing the liquid. You will usually see cuppers sampling coffee using a spitoon. It is considered poor etiquette to put your spitoon on the cupping table during or after a cupping, so be sure to dispose of any spent coffee liquid in an appropriate and hygienic manner.
Fortunately our physiology makes it easy to experience the full flavour sensation of a coffee without swallowing it. Heath explains that due to the non-equilibrium volatilisation that occurs after slurping, ‘It is quite unnecessary to swallow any of the brew to reach a full sensory judgement.’ (H. B. Heath, 1988)
A paper by Youssef et al, (2017) described evidence that aspirating increases the intensity of flavour in foods or drinks. They examined a group of 207 UK-based consumers, each giving their opinions on the flavour of soup. Panelists were fed soup in bowls and cups and were invited to sip and slurp the soup. The authors commented that the soup was rated as being ‘significantly more intense’ when it was slurped rather than sipped. Additionally, the participants reported that they enjoyed the soup ‘significantly more’ when they sipped rather than when they aspirated. This might initially suggest that it is a mistake to aspirate because it is proven to reduce one’s enjoyment of a soup. However, cupping and QC is there to help us identify any flaws in what we are tasting. Because aspirating increases the perceived intensity of foods and drinks, that’s why we do it.