How to use rice hulls?

[franc1969]

When running down my list of questions, I started searching about rice hulls. There is a lot of mentions of them to create channels in the must when pressing, particularly when pressing slippery labrusca-type grapes. But nothing that says exactly *how* to use them. Do you mix in, layer, what? And if you are using them, is there a sanitation issue? I assume something from a wine supply place is clean and ready to use, but are they in need of treatment for already fermented wine? Does the kmeta after pressing take care of this?
And would using a bladder-type press need less use of rice hulls than a screw-type press?

 

[Johnd]

When running down my list of questions, I started searching about rice hulls. There is a lot of mentions of them to create channels in the must when pressing, particularly when pressing slippery labrusca-type grapes. But nothing that says exactly *how* to use them. Do you mix in, layer, what? And if you are using them, is there a sanitation issue? I assume something from a wine supply place is clean and ready to use, but are they in need of treatment for already fermented wine? Does the kmeta after pressing take care of this?
And would using a bladder-type press need less use of rice hulls than a screw-type press?

http://blog.juicegrape.com/index.php/2019/10/pressing-with-rice-hulls/

 

[Rice_Guy]

* How: rice hulls make an excellent filter aid! to use them they should be mixed with the food, , , which on a factory scale means having a conveyor continuously dumping em on the product conveyor. They are basically inert about 1/3 silicate, flexible 1 cm long fibers.
* all rice hulls have some flavor, I describe it as cardboard.
* usage? I would do visual. Hulls are light, I can get about 10 lbs in a 50 lb rice bag.
* there are two types of rice hulls which are produced. The type from parboiled rice will have been steeped/washed with water and cooked with 5 to 10 psig steam. Parboiled hulls will be extremely clean and what I would use for filtering crushed grape/ other fruit pulp. The other type is from raw rice and will have more dust etc from the bin.
Parboiled will be readily available from the Arkansas delta. The non-cooked from all rice growing regions ex. the California valley. Hulls have no cash value, ie we pay folks to put truckloads of em back on the field. You will be buying shipping.

 

[franc1969]

I saw that post, John. One of the confusing ones- pouring loose hulls onto uncrushed grapes, and no photo of the item in the juicegrape store.

 

[franc1969]

This is great info- thanks. Adding the word 'parboiled' brought up better info from google. So the same brand/bale of parboiled rice hulls I buy for planting use is the same bale sold by several wine/brew places- but I can get it much cheaper from the landscape supply place. I'll only use them for food out of a new bale though, mine has been out in the greenhouse.
Mixing in is what I thought should happen, but all the info I initially found was pointing to brewery use in mash, or no info of how to specifically use in winemaking.
They should help when pressing ground apple as well- when not using the common layered tray and rack type of press.

 

[Johnd]

I saw that post, John. One of the confusing ones- pouring loose hulls onto uncrushed grapes, and no photo of the item in the juicegrape store.

They’re pouring those hulls onto the uncrushed grapes prior to pressing them, perhaps to make a light colored wine from dark grapes, like a white Zinfandel. Reading further down, the instructions are given to mix the hulls in with your skins as you load the press.

 

[mainshipfred]

From my experience helping at wineries rice hulls are only used on white or rose wines that will not be in contact the skin for very long. Not only does it create channels but the sharp points also help puncture the grapes for better extraction. On thin skinned or over enzyme'd reds I've found if you do a light press, fluff the skins and press again you can press harder without a problem. My new regime is to press 3 times and the third time you can press as hard as you want without an issue.