Adding Apple Peel to Fermentation

[Chalkyt]

Something to ponder during the holidays.

Recently, I stumbled across an article that suggested apple peel contains more flavour compounds than the pulp, and asked the question ”‘why isn’t extra apple peel added to grinding and pressing” or even into primary fermentation in order to enhance the flavour of cider. Especially as extra skin may well be available as it is probably discarded in activities like pie making, fruit drying etc. and could be frozen until needed.

The suggestion was that freezing or microwaving the peel breaks down cells and makes polyphenols readily available to the yeasts. The biochemistry is way beyond me, but does the idea have merit?

We tend to discard the pomace (which probably contains much of the skin) and only work with the juice. So, has anyone added skin or pomace, dried apple, etc to their primary fermentation and noticed any worthwhile improvement in flavour or complexity.

To make the maths simple, assuming that the peeled skin is 1mm thick then this would be about 10% of the pulp. Would adding extra skin or even (say 10%) pomace be worthwhile. I guess that coring apples might have a similar effect as the core is about 10% of an apple.

What has prompted this train of thought is that down here we are getting towards the start of Autumn, and this year have an abundance of apples. But, we had a wet spring and early summer and there is the chance that the apples may end up a bit watery, low in SG, and lacking in flavour.

Any thoughts?

 

[Hoppy2bmerry]

Interesting question to which I do not have an answer. I did want to make a “blush” cider and added black grape skins to steep for a few hours, just for the color. It was a tasty batch and a year later I sent it to a competition and did not declare the grape skins, well one judge still tasted grape and didn’t count it as a flaw. So yes, based on that, skins could indeed add to the flavor, I’m just not sure if too much would be perceived as astringent or something else that would need to be balanced.
Pomace may be nutritious, but also messy to the process unless you would pass the cider through a filter for secondary or packaging.

 

[JulianDave]

I love this out of the box thinking. I have no idea, but I think it's worth experimenting with.

 

[Kees]

Isn't that why some traditional cider makers wait a couple of hours or days before they press the crushed apples?

https://galipettecidre.com/story/

 

[Chalkyt]

Yes, something like that. I understand that maceration is a traditional practice that allows time for O2 to affect (i.e. oxidise) any tanins in the pomace and produce some colour and mellow their bitterness and astringency, as well as allow enzymes to work on pectin and improve the yield (according to Jolicoeur).

The article was taking another step, pointing out that most of the tanins and flavour compounds are in the peel, with red having more than yellow which has more than green.

What caught my attention was that half of my trees are Red Delicious where the peel has four to five times the flavour level of the pulp and was the most tanic of all the skins tested. I have made an almost straight Red Delicious cider in the past but found that it needed malic acid addition to spark it up a bit.

I will certainly be doing a test batch with extra peel in a couple of month's time when apple pressing season is upon us.

 

[AzOr]

A few years ago my wife made a few pies after visiting a local orchard. I saved the skins and froze them.
Later I added a large ziploc stuffed with skins (she made 4 or 5 pies) to a 5 gallon batch that just started fermenting.
Honestly I didn’t notice a difference but with cider it’s difficult because of the variation in the fruit (I press my own).
That being said, it felt good not to waste the peels.

 

[Chalkyt]

Yes, SWMBO said that she would be happy to freeze and use the apples without peel since she adds some apple pulp (high in pectin) to low pectin fruit jams to boost the pectin (makes jams set, apparently). So, I might be on a win-win. Anyhow, with my own apples I can afford to muck around with a few trials... the idea of adding peel seems to have some merit.

FYI, the suggested rate is to add the amount of peel that would come from about 10% of the apples pressed. . I don't know how big your ziploc bag was, but I guess 5 gallons of cider come from be about 50 kg (100 lbs) of apples, which sort of translates into up to kilogram (2 lbs) or so of extra peel. Hmm, that is a lot of peel!!

 

[madscientist451]

If you have decent apples, pressing the juice out is all you need to do, your cider doesn't need any help. Grinding and pressing the apples is enough work on its own, adding the extra step of having to strain out apple peels seems like it wouldn't be worth the trouble.
However, if your cider is missing something, why not try it?
I'm planning on making a batch of apple sauce this week, and I usually toss the peels in the compost, but I' think I'll try an experiment and add water and frozen apple juice concentrate and see how it comes out.

 

[CKuhns]

Bump, to see how the "experiments" do.

 

[doublejef]

I plan to do it since a while but I never found the energy once I start pressing. And I still dindn't buy a good apple peelert to do it quickly, something electric, and reliable should help a lot.
My idea was to peal some of the appel until I have enough skin to fill up a bucket of 30l then add fresh pressed juice in there to the nearly top making the skin immerged. Then let it fully ferment (naturally) for 2-3 month and put the cider without skin and gross lies into the rest of my fermented cider (800l or so).
Second option, freeze the skins and wait until I have fermented cidre and then put the skin to soak into cider in the same 20l bucket.
Alcool should help to protect from mold and also make the absorption of the element of the skin faster. I also can close the lid with no head space to avoir oxydation.

I prefer to do that because I not confortable when there is some solid part floating in my cider, that's generally where green spots are showing up. If it happen, just some litters and time is lost, not my entire batch.

 

[JulianDave]

It just occurred to me that experimenting with skins may be better done with your own fruit as store bought apples have some type of wax on them. That might prevent the contact you would be hoping for?

 

[doublejef]

It just occurred to me that experimenting with skins may be better done with your own fruit as store bought apples have some type of wax on them. That might prevent the contact you would be hoping for?

For sure alwayys better. Moreover, with store bought apples, skin will also have some pesticide residues