Fall is fast approaching here at Orchard Ridge Farms, and with it, a bountiful harvest of apples.
Here’s a seemingly simple question: when do you pick an apple? Well, when it’s ripe, of course.
But that’s when the issue becomes more complicated. How do we know an apple is ripe? There are many subjective ways to determine when a certain variety is ready to be picked. The easiest (and my favorite) is by taste. Sure, we can start picking apples when they taste right, but my taste may differ from yours. An apple that tastes sweet and tart to me could taste too sour for someone else. Another way to guess ripeness is by date. When is a Jonathan apple, for example, usually ripe? Conventional wisdom might say mid-September. But based on weather, those dates can fluctuate two weeks or more from year to year. In a long, hot season like 2012, apples were picked much earlier because the trees had a month head start in the spring. This year, the ripening date will be closer to average, or maybe even a little behind because of a slow spring and mild summer temperatures.
We can also try to gauge a variety’s ripeness by its color. Usually apples with fully developed color are approachi
ng ripeness. For example, a yellow-skin apple like Golden Delicious or Goldrush will lose its green and become evenly golden, often with a slight red blush. But again, visual ripeness can differ year to year. Lots of cloudy skies can reduce coloration and ripening, and nighttime temperatures can also have an effect. Another visual indicator is the apple’s seeds. Fully mature apples will have dark brown seeds, whereas apples that have not reached maturity will have white or light brown seeds. However, some apples have brown seeds and are “mature” before they begin to accumulate lots of sugar and taste good. Most grocery store apples are picked when they are technically mature, but way way earlier than they should be to develop their full flavor.
So what’s an apple grower to do? Luckily, there is a specialized tool to solve just this problem. It’s called a refractometer, and it offers the best way to measure ripeness: by sugar! The refractometer looks similar to a kaleidoscope, and it measures how light is refracted by passing through an apple’s juice.
It’s as simple as cutting open an apple, squeezing some juice onto the front plate, and taking a look through the eyepiece. The higher the sugar, the more light is refracted, which then shows up as a percentage in the eyepiece. This time of year, apples are slowly accumulating sugar as they ripen, and the typical range is 14-18 degrees brix (another way of saying % sugar).
I’ve been checking brix levels everyday this week. Here are the latest readings:
Gala – 15 % (picked today! Very small amount, only a couple bushels. Find them at our roadside stand next week before they’re gone!)
Cortland – 14-17% (picked some today, the rest next week, available at markets next week)
Honeycrisp – 15% (picking next week, but holy cow these are sweet already! Available at some markets next week)
Jonathan – 13-15% (still a little green under the skin, but should be ready to pick soon)
These are all the early apples. The mid and late season apples are a little slower to accumulate sugar, but a variety like GoldRush, when fully ripe near the end of October, can easily hit 17-20 %.
Besides being able to check ripeness scientifically, I still think biting into an apple is a great way to check. I invite you to do your own “ripeness” taste test with our apples this fall.
– John, Orchardist