The Role of Closures in Wine Flavor Management | November 6, 2012

1. The Role of Closures in Wine Flavor Management|November 6, 2012 Glenn O’Dell| Closure Trials: Industry Experience

2. Why Worry About Closures? • The closure is the part of a standard wine package that has the most direct impact on product quality characteristics. Some of these characteristics are obvious, some less so. For example: • Bottling line “machinability” • Tamper evidence • Ease of opening/reclosing • Leakage • Off flavors • Flavor scalping • Oxygen exposure/bottle age/shelf life • Some types of closures may be better than others in one or two of these characteristics, but none is best in all of them • Ultimately, selecting the best overall closure(s) for your wine(s) is a critical factor in controlling wine quality

3. Why Run Bottling Trials? • There is no other way that I have found so far to effectively simulate these impacts in a lab setting • The solution I have used: run variables of interest in parallel using “live bullets” and evaluate them over time • Getting samples that are truly representative of real world production (live bullets) can be a challenge • Will share some of my bottling trial tribulations

4. Life Cycle of a Closure Trial • Identify variables you want to test • Create a written plan • Discuss that plan with team members • Optimize control during production • Evaluate results • Communicate results • Repeat as required

5. 1. Identify Variables to Test • Closure options • Closure type (cork, synthetic, ROPE, Zork, VinLok…) • Different manufacturers of same closure type • Variations within a type from same manufacturer • Variations within a lot of the same type from the same manufacturer • Machinability Issues • Feeding • Application • Packaging interactions (e.g. wax seal)

6. 1. (cont’d) Identify Variables to Test • Ease of opening/reclosing • Torque • Extraction Force • Reinsertion • Oxygen exposure • Headspace contribution • Oxygen expressed from the closure by compression of cell structure (corks and synthetics) • Oxygen Transfer Rate (OTR) of the package • Off flavors, Leakers, Tamper Evidence…

7. 2. Create a Written Plan • Identify variables being tested • Choose from the list above or make up your own • Identify variables to be controlled • Wine, glass, line speed, DO… • Outline action plan for trial • Who, what, when, where, how many… • Outline action plan for evaluation of results • What tests, when, how many replicates

8. 3. Discuss with Team Members • Identify key members • You need them on board • Share rough draft with them • Each may have info you don’t • Make any necessary revisions • No point in running into a brick wall • Copy final design to all key team members • Everybody has the same road map.

9. 4. Optimize Control • Everything will not go as you planned • Be on the floor during the actual production run • Do not panic when things start to go awry • Take corrective action as required to minimize the impact of the unforeseen • Try to foresee it next time

10. 5. Evaluate Results • Decide on what tests you will use to objectivelymeasure the characteristics you want to test • Mechanical tests (extraction force, torque etc.) • Analytical (SO2, absorbance, oxygen, TCA, etc.) • Sensory (ultimately the most critical, but the toughest to get reliable results) • Determine how many replicates to perform at each interval (to control for bottle to bottle variation) • Realistically estimate often should the tests be repeated, and for how long • All wines change over time • How long will the data be meaningful

11. Optical Oxygen Measurement • A powerful tool • IMAO Oxygen control is one of the most critical factors in closure performance • Optical systems allow nondestructive, repeated measurements of oxygen in the same bottle over time • Mocon, NomaSense, Oxysense all have similar systems; there are others I have not tested • All allow measuring oxygen in the liquid or gas phase from the outside of the bottle through the glass wall • We first it used in bottling trial in the 2007 WB trial

12. Oxysense Optical Oxygen Measurement

13. Allows Calculation of Total Measured Oxygen (TMO) • DO is (ppm or ppb) is oxygen dissolved in the liquid • With liquid volume, allows calculation of mg of oxygen in liquid • Headspace oxygen (%) is the concentration of oxygen above the liquid. • With headspace volume, allows calculation of mg of oxygen in headspace • Add these mg together and divide by liquid volume, and you get TMO (in mg/L) • I initially hoped to be able to measure TMO over time in bottling trials and calculate OTR for various closures

14. Why Using Wine Didn’t Work to Calculate OTR Oxygen permeating closure (OTR Oxygen molecules in air Oxygen molecules in gas phase (headspace) equilibrating with liquid DO Oxidizable wine components (pigments, tannins, alcohols…) in wine providing oxygen “sink” DO in Liquid phase (wine) equilibrating with oxidizable components in the wine Wine component in oxidized state

15. Average TMO in Wine: Full Scale

16. Wine Is an Oxygen Sponge • Initially after bottling, wine components are taking DO out of solution faster than it can be replenished from the headspace or from oxygen getting past the closure. • It happened fairly quickly here. • This is Sauvignon Blanc; it happens even faster in young red wine.

17. The Significance of TMO • This trial was the first time that we had quantitatively evaluated total oxygen exposure at bottling. • It was a surprise to find out how much higher the TMO was in the ROPE packages than in the insertables • WB installed a nitrogen drip system on the ROPE line shortly after we generated these data

18. Average TMO in Deoxygenated Water

19. Figures Don’t Lie… • But be careful when evaluating data. • Because of the volume of data we were now generating, I initially focused on average values for all replicates of each variable (last chart) • Those average could lead you to draw some questionable inferences (next chart)

20. Why Replicates Are Highly Advisable

21. 6. Communicate Results • Toughest part of the process • If you do trials like we have, you generate lots of data • Most people want a simple answer • I am still looking for one • I am confident that I know a lot more about closures than I did 25 years ago • Sometimes it can be hard to explain that to folks who already know everything they need to know based on the last bottle of wine they opened that was hard to open, corky, oxidized, reduced…or wonderful

22. 7. Repeat As Necessary • Just when you find some answers, you will have new questions, from: • New suppliers • New variants from existing suppliers • New questions • New people asking to retest old answers • Go back to Step 1 and start over • I currently am planning yet another massive trial, tentatively scheduled for March of next year

23. My Conclusions (to date): • There are currently four primary types of wine closures in use to day: • Traditional, punched bark cork • Technical (agglo/microagglo) cork • Synthetic cork • Screw Caps (ROPE) • None of them so far has demonstrated to me overall superiority for all wine applications

24. A Good Cork is a Good Closure • That is not by accident: cork was the closure in use when traditional winemaking styles evolved • Unfortunately, regardless of price or visual grade, all commercial cork lots still contain a significant % of bad corks (taint, leakers, xs oxygen exposure) • Visually, a bad cork can look good…and vice versa. • If the cork industry could figure out how to consistently deliver anything close to 100% good corks cost effectively, we would not be having this discussion today • I sincerely wish they would figure out how to do that

25. Technical Corks Have Serious Potential • Technical corks (made from bark agglomerate or micro agglomerate ) are semi-manufactured • Traditional technical closures, those without an effective method for taint removal, have a history of recurring taint issues • Depending on the manufacturing process and its controls, some technical closures may prove to be the optimum closure for a wide range of products • Positive, consistent systems for removal and control of taint compounds to below defined, acceptable levels is likely to be a key to their acceptability • Consumer acceptance of their esthetics can be an obstacle

26. Synthetic Corks Are Consistent • They are manufactured to defined tolerances, not grown • Their manufacturing processes can be (although not always are) subject to tight controls that are capable of delivering a consistent product • They eliminate taint • They actually minimize random oxidation • Traditional synthetics deliver a uniform, but somewhat shorter, useful shelf life • Newer, low OTR synthetics show real promise

27. Screw Caps are Consistent and Capable of Very Low OTR • Lowest OTR is not necessarily the best closure • Wine does continue to “develop” in the bottle • Depending on the screw cap and the wine, some caps appear to not provide enough OTR. • IMAO the greatest success in the wine industry comes when you offer the customer both sizzle and steak • Unscrewing a cap does not evoke much mystique to me…will the sound of breaking pilfer rings ever trigger the same anticipation as popping a cork?

28. In Closing… • I am very confident that almost everyone in this room knows much more about wine closures today than anybody did in 1987 • It has taken a lot of testing, including huge numbers of bottling trials, to get us where we are today • I think it is safe to say that, in general, all wine closures are better now than they were back then • Despite that, all I can say is that I am personally still looking for closure • If you decide to do some testing on your own, happy trials to you

29. Tasting • For your pleasure I have brought some samples from one of the older trials that we still have available • By way of introduction, I hope you didn’t come here solely based on the expectation of getting to taste wine • 2006 Woodbridge Sauvignon Blanc • Bottled in March, 2007 • Well over 5 years old • 15 variables tested, 6 shown here • 1 bark Cork, 2 screw caps, 3 synthetics • These are the same variables shown in some of the earlier charts • All of these samples are clearly well past their prime, but considering all of these bottles were produced from the same lot of wine and bottled at the same time, they are showing some pretty dramatic differences that I am sure you won’t see anywhere else