Wines & Vines

WineEast va cuum ba rri er dosing are bottling options to eliminate O2. excessively carbonate (saturate) the wine prior to bottling; therefore, N2 is preferred (Ough, 1992). Oxygen elimination at bottling Bottling is the last winemaking process during which dissolved oxygen can be added and have a significant negative impact on the aging potential and quality of wine being released to the consumer. Thus, extreme care must be employed in minimizing the amount of oxygen entry at bottling. Oxygen has the potential to dissolve into the wine at every stage of the bottling process. A recommended level for total dissolved oxygen should be below 1.25 mg/L in bottled red wines and 0.6 mg/L for white, tion of CO2 in mg/L of wine. blush and rosé wines (Fugelsang, 2009). Wine filtration prior to bottling is another Major sources of oxygen diffusion into wine source for oxygen pickup. During filtration, at bottling occur during wine transfer, filtrait is important to operate the filtration unit tion, filling and headspace levels of the botaccording to the manufacturer's directions, tling tank, filler and bottle. Each process will making sure all connections and pads are be described in further detail below. tight to prevent oxygen entry. Purging of When transferring wine to the bottling air from the filter pads and transfer lines is tank, it is advisable to purge the tank and also a recommended practice. transfer lines as mentioned above with N2 or CO2 prior to filling. If any headspace is Wine entering the filler bowl is typically present after filling the bottling tank, it is one of the most problematic sources for important to use an inert gas on the surface oxygen pickup. The filler bowl should also to prevent oxygen from dissolving into the be covered with an inert gas. Depending wine. Often, a mixture of N2 and CO2 can on the type of filler used, the process of be beneficial, especially for white wines. filling wine bottles can increase the levels Maintaining a slight but constant presof dissolved oxygen by 0.5 to 2.0 mg/L sure over the headspace is recommended. (Peynaud, 1984). The length of the fill Although CO2 levels around 300-600 mg/L spouts as well as the type and force of the can enhance a young white or light red jet may influence the amount of dissolved wine (Peynaud, 1984), caution must be oxygen. Therefore, it is advisable that filling used that excessive pressure may cause too tubes be as long as possible depending on much CO2 absorption, providing a noticethe bottle. Providing vacuum prior to filling able tactile sensory perception and possible and flushing with 2 to 3 volumes of N2 has been reported to lower oxygen absorption at bubble formation. bottling (Boulton, et al., 1999). In addition, excessive CO2 levels can cause an increase in pressure, possibly After filling, bottle headspace is another pushing the cork out after bottling. Theresource of oxygen absorption. This is due, fore, the use and monitoring of CO2 in in part, to the variability of the bottle headthe wine prior to bottling by Carbodoser is space, which is influenced by such factors beneficial in adjusting concentrations up or as wine temperature, solubility of gases in down accordingly for these purposes. The the wine, bottle size and shape. To help Carbodoser is a relatively simple technique reduce oxygen ingress at this stage, the involving a glass tube measuring the injection of an inert gas such as N2 or CO2 can reduce the amount of oxygen in the amount of CO2 out-gassed from a fixed volume of wine. Comparing actual results with headspace. 1/22/09 9:47 AM Page 1 EasternWineLab_Mar09.qxp According to Peynaud (1984), a a calibration curve provides the concentrasmall amount of CO2 supplied to the bottle Need a Better Cork Supplier? All Natural Cork Closures Fresh Corks Directly From Portugal 4th Generation Family Cork Producer Free Branding Free Shipping Free iS Better Ask about our Progressive Discounts Experience the Slimcork® Advantage CALL TODAY phone (203) 681-7743 Cell (860) 335-0667 email: reliablecork@gmail.com • www.reliablecorksolutions.com EASTERN WINE LABS Serving the Analytical needs of East Coast Wineries WWW.EASTERNWINELABS.COM Ph 609-859-4302 Cell 609-668-2854 chemist@easternwinelabs.com AOAC Member Win es & Vin es AU GU ST 20 13 95

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