By: Tom Payette – Winemaking Consultant
Transfers are a large part of the day to day operations in the cellar and on the crush pad; yet, few documents exist what should be considered when doing transfers. Below are some ideas and tips to think of when transferring wine or juice at the winery. It is assumed the pump, hoses and receiving vessel(s) are all appropriately clean for the endeavor at hand.
Always vent both tanks and double check this operation is done. Often I will not only remove the airlock but I will unlatch the lid and flip the threaded latch inward so the tank top rests on top of the handle. This is just double assurance the tank I am transferring from and to is completely vented.
Assembling Your Hoses
Always place the pump as close to the tank you are coming from with as little hose as reasonably needed to get the job done. Do plan for being able to gently bend or curve the hose into the doorway in the event a racking is being done. Plan enough hose length for other future transfer needs when feasible. Also make sure to place the pump away from any water such as wash down areas or leaky faucets etc. These pump motors are electric and they generally are not made to be soaked with water.
Before you start the pump – taste the tank or barrels you are about to transfer or rack. Confirm it is indeed the wine / product you are interested in moving. Does it taste clean and what you expect? If not – contact someone above you on the winemaking ladder to confirm the flavors etc.
Checking the Connections
Always double check your connection to confirm the hoses run from the tank desired to the receiving vessel selected. Are the connections secured? Should you attach to the racking valve of the tank you are transferring from?
Are the lines secure at the pump? Is the bypass on the pump, if equipped, open or closed? Is there enough capacity in the receiving tank and did you look inside both tanks when you were venting them?
Valve at the Pump
For control I typically prefer to have a valve installed at the pump. This allows one to turn off the pump and immediately confirm the stop of liquid flow through the pump and lines set up. (Note: this is not done if transferring must.)
The pump choice is often related to the wine and the overall goal of the transfer. If speed is needed – choose the fastest pump. If gentleness is desired – use your most gentle pump. A centrifugal pump can be very gentle but it may not be the best choice for a red wine “pump over”, etc. Know what limits each pump has and generally how they operate etc.
Staying with Your Transfer
Never leave your transfer. This is not the time to walk off into another area and to get distracted. A racking valve could inadvertently be left open or a door leak could be discovered. If a phone call, or other distraction, should come in that has you leaving the area – stop the pump and close all valves to the tanks.
Keep in mind the main goal of the transfer. If the wine is a delicate wine – use the inert techniques you have at your disposal. This could include gassing your lines, with carbon dioxide or your inert gas of choice, before pumping liquid. Gassing your receiving tank, as well, can limit exposure to oxygen. If the wine needs a touch of air – use techniques that may achieve that goal. An example may be splashing into a macrobin, or other open vessel, to give some air. Be careful here.
Oxidation Control (Inert Technique)
Is oxidation a concern during this transfer? If so – many winemakers will flush their hoses and receiving tank with an inert gas such as Nitrogen, Carbon dioxide or Argon. This can be done by simply connecting the hoses to the pump, opening the bypass and flushing the inert gas from the receiving line all the way through until you are comfortable the inert gas has reached the far side of the transfer connections. Then attach the hose to the bottom valve of the receiving vessel. Further protection can be gained by flushing out the tank with an inert gas as well. [Many wineries now have the ability to make dry ice (carbon dioxide) on site and they will place dry ice in both vessels while the transfer is being done]. These processes can be used on juice transfers also – not just wine!
Air – introduction
In some cases you may want some air introduced into the wine. If that is the objective you do this by attaching to the racking valve of the receiving tank at the start of the transfer. Splashing will occur, in the receiving tank, until the wine reaches that point, of course. This is a small amount of air especially when working with a “tight red”. Other more severe forms of air introduction can be achieved with splashing into a bin and transferring out into the receiving tank, splashing into the top of the receiving vessel or starting the transfer and throttling back the valve on the suction side of the hose (positive displacement pump only) while slightly cracking the hose connection to allow air to suck in. [Please have an experienced winemaker present to justify how or if these processes should be done as described in this section]. One could also assemble a special “T”, with valves, for more precise control on the suction side of the pump. This process may be hard on the pump and damage it if not done properly.
This is often a term one will use when the amount of solids that may come over into the receiving vessel is not that large of a concern. Examples of this may be when racking off a white juice after cold settling. We want to make sure we retain as much of the saleable volume as possible so we may elect to have small portions of solids come over into the receiving tank. [This is less of a worry if we have a Lees Filter Press is on site].
Another example may be when racking off bentonite. Small amounts of the fluffy bentonite layer may be allowed to transfer over, again, to make sure we retain as much saleable volume as possible but not jeopardizing the heat/protein stability of the final wine in the receiving tank. Don’t get carried away with this concept but don’t be wasteful either. It’s a balance.
I often relate to new winemakers in a manner that tell them your senses are incredible when working in a winery. Your eyes are a large part of seeing that the transfer is happening as planned but your ears can also be a huge part of catching problems.
Always stay near by the tank and listen for falling liquids, pump noise changes etc. Once wine or juice has filled past any possible orifices, and no leaks discovered, then one can more freely move around the cellar with periodic checks. Do not completely leave the area and always “have an ear on the situation”.
Many wineries have translucent hoses. Watch the liquid as it moves through the lines. Do you see air? Why? If the wine lines start to contract or expand – take note as to why. Did someone close a valve or has some other physical function changes the stature of the hoses. Hoses typically don’t move, without reason, so be aware visually to this indicator something is happening.
Chasing Your Liquid
At the end of the liquid transfer you may wonder how to empty your lines. If you have a bypass you can often hook up an inert gas and push the liquid all the way through. If you don’t currently have that option you can attempt to “push” the juice or wine with chlorine free water. Simply place the suction line in water, after the wine or juice has vacated enough internal line, and allow the water to run through the pump. Look through the hose to understand when the water reaches the receiving tank and then turn the pump off and shut the tank valve.
Never Run Your Pump Dry
In most cases we all agree not to run your pump dry. The pump needs liquid in order to make sure heat is not created. There are variable options to this statement so if unclear …. Never run your pump dry. That is the safest bet.
Transfers are a large part of moving your precious liquids around the winery. Stay nearby, listen to the equipment while visually looking for leaks. Also – know what your goals are. This should not be a mindless transaction in the cellar and the more you think through your goals for each wine the more creative ways you can achieve them even during these everyday tasks. This is part of the winemaking process.
Other Helpful Tips
Recall no hoses should leak in the cellar. The paths for these leaks are areas for bacteria to breed and grow. Further understand a leaking hose on the discharge side of a transfer wastes wine; but a leaking hose on the suction side of a transfer will mostly introduce air and possibly bacteria. Oouch.
When starting a racking I like to attach all the hoses and then open the bypass on the pump (if equipped) without starting the pump. I then open the valve on the tank to be transferred. This allows the winemaker to track the liquid, see that all valves are open and working, look for initial leaks and confirm all is performing well before turning the pump on. It is very gentle and should minimize air, oxygen or gases from being dissolved in the liquid.
In general, winemakers typically transfer out of the racking valve of the tank being racked from and into the bottom valve of the receiving tank. There are, or can be, exceptions to this rule.
Take into consideration the temperature of the juice or wine. As a reminder cold liquids dissolve more gases into them than warmer liquids. Therefore a colder wine / juice may dissolve more oxygen than a warmer liquid.
Always clean the tank you emptied right after it is empty. It cleans up so much better and actually saves time in the long run.
A racking is typically a term used when the transfer is started from the racking valve and then finished while “pulling the liquid” through the side doorway of the tank. One typically uses a flashlight to discern the solids layer while obtaining the clear liquid.
A transfer is often a term when going from the bottom valve of one tank to the bottom valve of another. Still being cognizant of solids at the bottom but understanding the wine / juice is generally “clean”.
Be sure to record all transfers: recording the tank transferred from (varietal and vintage), the volume(s), the receiving tank, date and gains or losses.
If racking barrels you should taste each one of them first. It is not uncommon to find the last barreled filled previously is more “reduced” than the others due to more solids in that barrel. If this proves to be the case I will either rack that barrel first, with most of the air becoming in contact with that volume, or treat it for the reduction and rack it first. In any case this may slightly mitigate some of the reduction. Plus – if one barrel is not what you expect – you want to identify that before you pump it out into a larger blend.
Have fun and make sure your transfers are successful, with intention and objective and with as little liquid on the ground as possible. You are “pumping money around I like to say”!
Verbal discussion with Mr. Jacques Boissenot, Mr. Jacques Recht, Mr. Chris Johnson and Mr. Joachim Hollerith.