Wine bottling is the last step of the winemaking process and can have a very important impact on wine quality as it reaches the end consumer. Aside from bottling issues due to too high Total Package Oxygen, bottle to bottle variation has been identified as a potentially major technical issue within the wine industry. Accordingly, different bottles of a given wine (e.g. same label and vintage) purchased in the same outlet and therefore intended to be all the same, can show major differences due to various factors. Our Enology Team has carried out different surveys in various countries to investigate the extent of this phenomenon and the potential implication to consumers’ enjoyment of wine. Results from our different studies show that 40 to 50% of the bottles collected in the market show analytical variations, with almost half of them showing also perceptible sensory variations. In other words, for the same batch of wine (e.g. same grape, vintage, packaging, label and bottling), almost one in four bottle show differences that could be picked by consumers. Different sources of variation have been identified such as varying bottling performances from beginning to end of the process, closure oxygen ingress consistency, bottle bore variations or presence of unwanted aroma compounds released from the closure (e.g. TCA).
In the frame of our Enology research activities, we have developed an integrated procedure to assess bottle to bottle variation of a given wine label. Today, we propose wineries with a well-thought, technical approach to control the consistency of their production at the retail level.
The proposed method is based on:
- Collection of bottles directly from market shelves.
- Chemical analyses performed in our laboratory.
- Sensory evaluation: provid analytical results that are deemed different enough, a sensory assessment will be performed on the same bottles as the ones used for chemical analyses.
- Evaluation of bottle to bottle variation can allow wineries to get a clear view of how consistent their brands are in the market.
- Define the variation spread
- Understand consequences on customer loyalty
- Perform performance benchmark by comparing their brands to the identified competition.
- Identify sources of variations and focus back on production to implement improved bottling procedures.
- Work on closure selection.