Wines can be ruined in just one moment: during bottling.
After all of the attention in the vineyard, all of the details that go into making the wine…
…we can completely ruin the quality with poor bottling practices.
While this operation seems somewhat straightforward, and may often become boring, there is an incredible amount of variability that goes into packaging wine. There’s also a number of things that can go wrong during bottling operations.
Let’s review a few key concepts that are often missed during bottling operations:
Understanding Oxygen Pick-Up During Bottling Operations
Oxygen is both good and bad for a wine depending on when the oxygen is introduced to the wine and at what concentrations. While many winemakers may worry about oxygen during primary fermentation, this is not the production operation where oxygen is truly a problem.
Oxygen integration becomes more problematic during wine storage in tank/barrel and through bottling.
By bottling operations, ideally, very little oxygen should be introduced to the wine. However, there are plenty of places where oxygen can integrate into the wine during bottling operations:
- through the tank as wine volume is drained,
- the filtration processes and hose lines, in bottle headspace, and
- through the closure.
Many practices are often encouraged through bottling operations to minimize dissolved oxygen (DO) pick-up during bottling operations. This includes things like:
- flushing hose lines with inert gas,
- flushing the draining tank with inert gas as wine volume decreases, and
- flushing bottles with inert gas prior to filling.
However, not all wineries integrate all of these processes or integrate them correctly.
During the webinar series, “Everything You Wanted to Know About Wine Bottling,” wine QA/QC and winemaking expert, Zoran Ljepović, offers a detailed explanation on oxygen integration through bottling operations and the various ways winemakers can minimize its impact during these processes.
Pre-Bottling and Post-Bottling Wine Specifications Tell a Bottling Operations Story
Wines should have a standard set of analyses conducted immediately prior to bottling (while in tank) and those analyses should be compared to post-bottled wine samples.
Because this provides the winery with an indication that bottling operations are conducted effectively.
As a consultant, I often see winemakers panic when bottles are re-fermenting even if pre-bottling chemistries did not indicate a problem (free sulfur dioxide levels were adequate for the wine’s pH, for example). However, many wineries do not measure DO, which, as described above, is heavily variable during bottling operations.
DO has a rather large impact on free sulfur dioxide retention in the bottle. Thus, while this parameter is often overlooked by many winery operations due to cost or time inhibitions, the reality is that the lack of knowing DO in the wine can cause a lot of problems for the winery post-bottling.
However, other analyses are more straightforward. An example includes the wine’s alcohol concentration. As many bottling lines are flushed with acidulated sulfur dioxide sanitizer, or hot water, prior to bottling, some of the first wines that come off of the bottling line should be checked for alcohol content to ensure they have not been diluted with retained water in the bottling line. Failure to do so could result in the first few bottles of wine packaged with diluted alcohol concentrations.
Bottling Line Sanitation is Critical and Practices Matter. Wineries Should Validate Sanitation Practices.
The standard hot water specification used in the wine industry, “180°F hot water applied for a continuous and constant 30 minutes,” is a hot water sanitation that has been detailed for wine bottling operations.
However, can you verify that when using a hot water sanitation on the bottling line that you are verifying that the water went in at or above 180°F and came out through the fillers at or above 180°F? Are you verifying that there was no drop in temperature during the sanitation process?
The reality is that wineries relying on hot water sanitation are not only not verifying the hot water sanitation, but many are also not checking that the bottling line is properly sanitized prior to running the very first bottle on the line. Often, this is due to time and resource limitations. However, failure to check these specifications can, of course, lead to post-bottling problems in the wine.
Furthermore, very few wineries plan out bottling sanitation from how to clean and sanitize the hoses, filters, and bottling line before the start of bottling, to how to clean and sanitize the bottling line, filters, and hoses after bottling operations is complete. Again, due to the fact that a wine’s quality in bottle all comes down to this one operation, wineries and winemakers are encouraged to think through these processes and write down the standard operating procedures (SOPs) associated with bottling sanitation.
Wine Specifications and Quality Expectations Should be Outlined by the Winery and Reviewed with the Mobile Bottler or Packaging Winery Prior to Bottling Day
When using an alternative company for bottling operations, wineries are still encouraged to review specifications and expectations associated with wine bottling.
But what are those specifications?
An example includes the wine analyses that a winery will be checking pre- and post-bottling for bottling efficacy. This can include both chemical and microbial assessments. A mobile bottler or alternative packager should be aware that a winery is reviewing these indices and what their expectations are on deviations for each analyte.
Another example includes reviewing bottling line sanitation practices and how the bottling line sanitation is verified during bottling. Who is responsible for ensuring a bottling line is still sanitized if there are stops-and-goes in the bottling process? Who is responsible for ensuring the final filtration is working properly, and how is the filtration being verified that it is working properly? How are mobile bottler employees handling packaging (i.e., Are they wearing gloves? Are they trained for proper glove wear? Etc.).
All of these questions and details should be discussed by both parties well in advance to the actual bottling process to ensure the mobile bottler is meeting the expectations of the winery. If the mobile bottler is not meeting those specifications, then it is then up to the winery to determine how they want to proceed.
Could Your Bottling Practices Use a Tune-Up?
Let’s be honest, most of us of are just hoping the bottling line is working effectively on the day of bottling. It’s a perfectly reasonable expectation given all of the work that goes into getting the wine prepared for bottling, and given the fact that bottling seems so routine.
However, many of us highly underestimate the variability associated with wine bottling operations. Furthermore, many of us lack an understanding of all of the details that go into the bottling process. Again, this is to be expected given the level of detail associated with “what can go wrong” with bottling operations.
Therefore, if you want an inside scoop into the many, many details associated with the bottling process from the perspective of a winemaking and wine microbiology expert, Zoran Ljepović, that managed bottling QA/QC for Constellation Brands for over 17 years, here’s your chance!
The “Everything You Wanted to Know About Bottling” webinar series is now available, pre-recorded, for individual purchase ($73). Purchase of this webinar series includes:
- Lifetime access to the webinar series, Everything You Wanted to Know About Bottling, through DG Winemaking.
- 4 Hours (split into 3 segments) of online webinars that you can watch in your own time.
- 24 Pages of typed notes of the material covered in the entire series.
- Notes go in order of the presentation and are split into 3 parts, which matches the webinar series.
- Some of the slide images are included in these notes when appropriate.
- Links are provided throughout the notes. Some links are to outside products regarding things discussed in the presentation. These are accessible to everyone. Additional links to DG Winemaking tools and documents are only available to DG Winemaking Members and Clients.
What is covered in the “Everything You Wanted to Know About Bottling” webinar series?
- Pre-Bottling Planning: from getting the wine ready for bottling to packaging considerations.
- Explanations and specifications on pre-bottling and post-bottling analytical assessments.
- Best practices associated with the use of mobile bottlers.
- Detailed images of Wine Bottling Quality Standards and Specifications, QA/QC Wine Checks Pre-Bottling and Post-Bottling, a Bill of Materials Spreadsheet, a Wine Specification Form (targets for analytical assessments pre- and post-bottling), and a Wine Packaging Specification Form (packaging details recorded and details regarding how the packaging should look on the final bottle).
- A review of how water sources and chemistry impact bottling.
- The ideal sanitation regime associated with wine bottling.
- How to verify a bottling line is properly sanitized.
- Skills required for bottling wine effectively and properly.
- An explanation on wine temperature during bottling and how it impacts fill height.
- A review on oxygen pick-up during bottling operations and the various ways to minimize it.
- Questions asked during the webinar series and answers to those questions.
The views and opinions expressed through dgwinemaking.com are intended for general informational purposes only. Denise Gardner Winemaking does not assume any responsibility or liability for those winery, cidery, or alcohol-producing operations that choose to use any of the information seen here or within dgwinemaking.com.