Should I filter my apple juice before fermenting for cider?

[Ariel]

I juiced several pounds of apples. There is a good amount of pulp left in the juice. Should I filter it out or just leave it alone and ferment it in my carboy? It looks like about 20% of my gallon carboy is pulp. I only juiced it and put in my carboy 30 minutes ago.

I used red delicious apples

 

[madscientist451]

You don't need to filter it, just let it settle and pour the juice off the pulp. Also, you might want to find some other varieties of apples to go along with the red delicious. The cider is going to somewhat "blah" with just reed delicious. I've experimented with using a Breville juicer with apples and I prefer to grind and press instead
After you pour the juice off the apple pulp, you might want to try an experiment: if there is a quart of pulp in the jug, add a quart of water, let it stand overnight and then taste it, you may want to pour off a quart of juice and add that to your cider to get back the volume you lost. If your juicer separates the solids like mine does, toss that in your experimental jug as well, there's lots of flavor and juice in the skins and other pulp.

 

[Chalkyt]

I have a lot of red delicious this year and they are very "pulpy", however the bulk of it does settle out quite quickly (but not completely clear). I normally just use them for "fillers" if needed, but this year decided to try making something useful out of them. As madscientist451 says, by itself Red Delicious is quite "blah", although they are great to eat.

I currently have a gallon "experimental batch" on the go. This had about 20% Pippins added and was still "blah" until I added some bits. It is now fully fermented so I have taken a few "test glasses" and along the lines of Graham's English Cider I have settled on adding up to a teaspoon of malic acid per litre (yes that much) to taste. The pH was above 4.0 and now is 3.3 (haven't checked TA but last time I did something like this it ended up at 7%). Also adding strong tea for tannin helped (3 teabags in a cup of boiling water, left until it went cold) helped a lot.

Still not great but it isn't "blah" any more and should be O.K. as a quaffer, but it does need a bit of sweetness to cover the residual "blah" (adding sugar to SG 1.006 seemed to be close to the mark). The next step is to sweeten it up to SG 1.010 then bottle and heat pasteurise at 1.006. In my case I use a test bottle with a pressure gauge and pasteurise at 2 volume of CO2 (around 30psi), but a soda bottle "squeeze test" would probably work O.K. too. If you don't want it carbonated then just sweeten to taste and pasteurise it there.

For sweetening I have produced an apple juice concentrate from Red Delicious (freeze some then let it thaw until there is only somewhat clear ice left... the concentrate thaws quicker than water so you end up with a brown pulpy concenterate of over SG 1.130... don't know what the SG really is since my refractometer only goes that high and I expect that the pulp will cause some distortion). On reflection I am not sure if it was worth the trouble doing this as just adding more juice (or sugar) before bottling would also work, but I was looking to add some "appleness"..

With the pulpiness, it is worth doing a primary ferment of something like 10% more than you need so you can discard the bottom 10% which will be very pulpy rather than trying to salvage it.

Hope this helps... have fun!