Wine Tanks
Special Purpose Wine Tanks
Special purpose tanks are often classified as fermentors, portable tanks, blending tanks, and bottling tanks.
Fermentors
Fermentors generally have a sloped bottom and a bottom door to allow the pomace and lees to be removed after fermentation. In tanks with volumes less than 1,500 gallons, temperature control, while desirable, is less critical, as the surface-area-to-volume ratio of the tank is such that most of the heat generated by fermentation will radiate away before the temperature gets high enough to endanger the yeast cells. Larger tanks need some sort of cooling system.
Closed-Top Wine Fermentors
Closed-top wine fermentors are used for non-oxidative wine fermentation (See Figure 22.1). Ideal for white wine production, completing red wine fermentation, storage and such processing activities as fining, settling, and clarifying juices and wines. White wines produced this way have a clean, fresh taste and are perfect for early drinking.
Open-Top Wine Fermentors
Open-top wine fermentors are used for oxidative wine fermentation and are used primarily for red wines. They are designed specifically for fermentation of whole or crushed berries, they typically have a larger circumference and shallower depth than closed-top wine fermentors.
Active Wine Fermentors
Active fermentors include integrated cap management systems, already discussed in Chapter 6. The main argument against using active fermentors is an economic one. These fermentors tend to be less flexible and much more expensive than open- and closed - top fermentors and multi-purpose tanks.
Blending Tanks
Blending tanks should be at least as big, or bigger than the biggest container in the cellar. The capacity thereof will be determined by the size of the cellar and number of products, but it is always more practical and cheaper to select the capacity so that it may also be used for ordinary storage. There will almost always be a lot of ullage in a blending tank, so it is always a good idea to install a positive-pressure nitrogen system on blending tanks to minimize unwanted oxidation during blending.
Portable Tanks
Portable tanks are designed to be moved by a forklift (Figure 22.4). A portable tank should be fitted with forklift pockets or channels at the correct load points so that one can use a forklift or a pallet-jack to move it without damaging the tank or its fittings. As with any wine tank, portable tanks should be constructed from either stainless steel (either 304 or 316 grade) or high-density polyethylene (HDPE) plastic.
Bottling Tanks
Any multi-purpose tank can be used as a bottling tank. Ideally, a bottling tank should have the following attributes. It should be big enough to hold enough wine for one day's bottling. It should be fitted with a positivepressure nitrogen atmosphere. It should have a cooling jacket, or internal cooling vanes/coils, that extends to the floor of the tank.
Click on the following topics for more information on wine tanks.
