Not getting enough juice from my apples

Question

I've just made a batch of cider from 16kg (35 lbs) of apples. Based on various sources (example), I expected to extract about 8L (1.75 gal) of juice - however, I only managed to get about 4.5L (1 gal), which I feel is too little trade off for the cost of the apples, nevermind the time and effort.

My method: I first chopped the apples into quarters using a kitchen knife, then ran them through a fruit mill to create a pulp. The pulp was then pressed using a press (both the mill and press are similar to the ones depicted here - apologies for the link to a commercial site but I don't have pictures readily at hand).

One thing to note: I thought the flesh of the apples seemed a little drier than some juicy eating apples I've had before. I'm wondering how much a role the type of apple play in the conversion ratio. The apples I got were a mix of "seconds" from a local orchard, mostly eating apples that were discarded due to cosmetic issues.

What can I do to get more juice out of the apples? I'm open to all suggestions but have a preference for non-electric means. I'm aiming to get closer to the 2/1 (kg/l) ratio that seems to be achievable using standard methods.

Answer 1

You can add pectinase (also called pectic enzyme) to your crushed fruit / to your must to increase juice yield. You can find it at your local wine making / home brewing store or online, e.g., on amazon.

Pectinase is an enzyme that breaks down the pectin in the walls in fruit. It's frequently used in (fruit) wine making. Think of it as the opposite of adding pectin in jam making: you do want the jam to gel, but for wine making you want as much liquid as possible, and no gelling.

You need about half a teaspoon per gallon (3.8 liters) of must. Stir the pectinase in the must before fermentation and let it sit for a few hours.

As a side effect, it can also reduce haze.

See this Winemaker's academy article or this article in the wine maker's magazine.

Answer 2

It is worth noting that juice yield will vary based on type and condition of the fruit. Apples lose moisture even when stored properly to the extent they can become quite wrinkled while still being usable.

I once harvested apples very late in the season and by the time I processed them, the juice I obtained was more like thin syrup.

You might want to check the gravity of your juice in case you can simply add water to get back to a normal concentration - you may not be getting bad yield. If this is the case your cider is likely to be very very strong after fermentation!