Sizing A Press

Sizing a press comes down to an intersection of 3 different questions: How much do I have to press? How much can I press at once with a given size of press? How long will each press cycle take? As with the crushing/destemming part of winemaking (and pretty much every other part of winemaking for that matter), the setup and cleanup will represent a significant portion of the day, so you don't want to plan on spending 8 hours presssing unless you feel like working a 12 hour day. In general you want to be able to get through the entire lot of wine or grapes in about 5 hours.

Keep in mind that when you're pressing must it will be between 30% and 35% solids. As you fill the press most of the liquid will flow right through and out referred to as free run wine/juice. So the volume of the press is going to correspond to the volume of solids that need to be pressed. For example, if you have 100 gal of fermented must to press, that only corresponds to about 35 gal worth of solids. To press 35 gal of solids through the 40L bladder press (10.6 gal) you would need to run about 3 press cycles in order to get the job done. If you can run a full press cycle on the 40L bladder press in about 45 minutes - which, as it happens, you can - then this press will totally do the trick.

Now seems like a good time to define what I mean by "press cycle." A full press cycle consists of filling the press, pressing, emptying the press and cleaning and sanitizing it for the next run. Now all you need to be able to figure out which press is right for the customer is to know how long the press cycle is for each model that we carry.

Keep in mind that times for running press cycles do vary based on the customer's equipment physical set up, practice, preparation and level of expertise. The two most time consuming parts of the process are 1) filling the press, and 2) actually pressing. With the bladder press this essentially consists of waiting for the bladder to fill...

Whole Grape To Must

It can vary but for most reds, we can expect that a ton of fresh grapes (2,000 lbs) will yield about 210-240 gallons of must which in turn yields about 120-130 gallons of finished wine. The variation comes from cluster size, stem size and ratio, amount of shatter, open vs. closed clusters, berry size, skin thickness, number of seeds, press pressure, etc.

Cage Size To Cage In Liters To Cage In Gallons

Using these estimates:

2,000 lbs of whole grape times .1125 = 225 lbs of must and juice times .35 = 78.75 lbs of solid must

So for example, a 70 liter press will press 87 pounds of solid must in one press so it could do around 2,000 lbs of whole grape that was 225 lbs of must and juice.