When a bin of fruit has gone dry (ie; it has reached the negative range on the hydrometer during a Brix reading), it is essentially ready to be pressed. But to ready a bin for pressing, you must first ready a barrel or two.
To do this, you need to fill a barrel with water to get the staves to expand and locate any leaks. If your barrel does have leaks, you need to leave the water in the barrel and hose the outside of the wood so that the fibers in the staves have time to expand. (Barrel stave wood shrinks up when absent of liquid.) Many winemakers try to keep liquid in their barrels during the months of the year when they aren’t being used to hold wine. Keep your barrels treated in this way and they’ll treat you well come harvest! Therefore, it’s a good idea to determine when you want to press a bin so that you can plan ahead and ready your barrels.
To check for leaky barrels, Ed has us fill a barrel partially or fully to detect leakage using only cold water. If a barrel is halfway filled and no signs of leakage are occurring, he’ll ask us to stop filling it and apply the clamp-like turnkey tool to rotate the barrel into place so that it can drain. To use this heavy tool, make sure the turnkey is grabbing one side of the barrel so you can slowly work the heavy barrel forward on the rack in order for the water to flow out of the bung hole. An excessively filled barrel is best drained by rotating it at a near straight up and down position, but not so much that it cannot properly use oxygen to propel the water so that it spills water out. But, if a barrel’s heads or staves start to leak, he’ll have us fill it up to give the barrel’s wood time to expand.
After a few hours, the leaks usually stop as the wood swells and the barrel dries on the exterior, indicating it is ready to be filled with wine unless it needs to get a quick power wash cleaning and steam. I think this is something that takes a lot of trust and understanding of how a barrel truly works. This would make me extremely nervous, thinking about potential loss of wine due to a barrel that might leak. But I think that if you follow protocol here, you’ll be fine. After all, winemakers go through this every year, so it’s not something urgent or unique.
Check your barrel to see if it’s still leaking water and if it’s not, rotate the barrel with a turnkey tool of sorts until the bung hole faces the floor and can drain the water out. Your barrel is now ready for use!
Note: If you are readying a brand new barrel that’s never seen liquid, and it happens to leak water excessively, there is likely something wrong with the wood, such as the wood was cut from a crooked tree with microscopic fibrous veins that also ran crooked and got cut in such a way that they stick out of the wood and/or end partway through a stave instead of running end to end per stave. There can be other issues as well, but lesson to learn here is that it would be wisest to always fill a new barrel with water to check for leaks instead of just assuming it will be leak-proof (no matter how much you trust your cooper). Do not just opt to add your wine without any water testing before.
To fill your barrels, you need to insert a metal “bullet” into the bin to suction out the juice leaving behind the seeds, skins, dead insects etc. This bullet is connected to a wand that is connected to a hose which siphons out the wine to flow directly into a barrel. Usually speed is a good level for siphoning without stressing the wine out. A metal wand that has a curved, pipe-like end on it is inserted into the barrel for more control. Make sure you hold a flashlight over the bung hole to observe the level of wine as it builds to avoid overflowing.
From this point, it’s just about pressing the grape remains or “must” to get every last bit of juice out to add to a barrel.
The press itself can run on automatic pressings or can be done manually. It runs on cycles that are programmed in by anyone using the press. This allows you to pre-set pressing cycles. As each cycle of pressing is applied, the bladder bag inflates in the press and works the fruit to press out remaining juice without stressing the juice out. To stop the press after its hit 1 or 0 bars of pressure, hit _4 and then ACK (acknowledge). To emergency stop the press, there’s a red cord that runs around it that you can pull. To restart the press from the emergency pull, you need to hit the blue tab/button located on the back side of the press.
The key here is to press the grapes slowly so you don’t damage the remaining juice. This same rule applies when you are filling barrels (either from the bin or from the sump of the press as the juice runs off the tray). As the press turns over to do another pressing, you can hear how the load of fruit lightens into pomace as the juice leaves it. Each cycle should apply a little bit more pressure until juice stops draining out.
Once completed, you need to clean the press in the same way you’d clean the hopper and destemmer equipment, but with an even extra TLC hygienically-speaking, since this sees juice that is now wine and not just freshly destemmed fruit. First off, always, always, always, turn off the press and turn off the electricity and unplug the plug for safety. Remember that even if you’ve turned everything off, there’s still electricity running between the socket and the press. Machines can, and have, backfired even in the off position. Safety first.
So, at this point, you’ve got quite a load of pomace in the press, so you’ll need to ‘door up’ the press so that it rotates the doors to the top for easy opening. Only open the doors as much as the width of the bin beneath it that is positioned to catch all the pomace. Then rotate the press so that the doors face down toward the floor. A big batch of pomace should dump out. Rotate the press back and forth to knock out big piles of pomace. After that, it’s up to someone to get up inside the press and manually scoop out all the remaining piles of pomace. To do this safely and with ample cleanliness applied, pallet jack the bin out and then have someone jump into the bin and crouch down. While this person is crouching, push the bin back under the press so that this person can begin scooping out all the pomace through the open doors area.
As the pomace falls into the bin, try to assist by level it around the person standing in the bin and scooping to avoid too much overflow. By the way, as the pomace falls, try to catch its aroma – truly one of the more intoxicating smells and not just due to the strength of the alcohol, but spices being released and concentrated fruit aromas. It’s a pretty astonishing experience.
The most challenging thing about cleaning the press is getting all those seeds out of the metals slots and those hidden grape skins lurking in the bladder of the interior of the press itself. I’ve taken to using the blade of a wine opener to poke seeds out. Other than that, it can be a very nice sauna-like experience to hose down the interior of the press and then Cleanskin it. It’s pretty enjoyable to be inside the press itself as it’s like a time capsule meeting an anechoic chamber.
Beyond press cleaning, you do need to do something with the remaining lees and must (pomace). The hope is that they dry out and do not form VA which makes cleaning those bins a bit more laborious as they must be hit with harsher chemicals in the form of citric acid and/or sodium metabisulfite or sodium percarbonate.