Where should I keep my apples?
The an age old question. Should I put my apples in a bowl to make that adorable centerpiece on my kitchen table or should they be relegated to the crisper in the refrigerator. From the number of glossy magazine covers picturing beautiful bowls of apples you would think that the bowl would be their favorite home. Apples are a bit less assuming. They prefer the refrigeration. Apples keep longest when held at 31-36 degrees Fahrenheit. So, you want to keep them in the coolest part of the refrigerator. Most home refrigerators don’t get that cold because the rest of your food would freeze, but the colder the better.
Why the refrigerator? Actually it’s all about the chemistry of how apples ripen. Unlike some fruits, apples continue to ripen long after they are picked off the tree. This ripening (or over-ripening affects the texture not the taste of the fruit. (ie. They won’t get sweeter just softer). This ripening is due in large to a a harmless, colorless gas that apples emit called ethylene. The emission of this gas is slowed by the cooler temperatures of a refrigerator causing the apples to last longer. Something else you should know: not all fruits and veggies are friends with ethylene gas. In fact it can cause some produce (mostly vegetables) to rot very quickly. So, it’s good to separate your crisper drawers by ethylene loving and not loving foods.
But the big secret to keep your apples tasting crisp and fresh is this: water. That’s right. Apples do best in an environment with 90% humidity. Did you know that your refrigerator is a natural dehydrator. Ever left apples (or other produce for that matter) in the crisper for a while only to slide open that drawer and find a very shriveled up piece of fruit. The good news is your refrigerator is functioning well…it works by taking all the water out of the air. The bad news…your produce will suffer. So, how to solve this problem: put a wet sponge or wet paper towel in the crisper. Or you can get a mini spray bottle and spray them with water every few days. This will really extend the life of your apples.
What if you just don’t have space in your refrigerator for all those apples? You can keep them in a cellar or unheated garage. Just be sure to insulate against freezing (they should be between 30-40 degrees) and keep them wet.
How do you keep your apples so long after harvest?
We are able to keep apples fresh and have them for sale as late as March because we employ a lot of the above…just on a much larger scale. We have a giant cold storage unit (refrigerator) that we keep the apples in until they are sold. You can see it pictured to the left. It is held at 32-33 degrees. We use a hose to regularly wet the apples to maintain the high humidity in the air. We are also careful of what varieties we choose to keep until the spring. Not all varieties have the same shelf life. Generally, the apples that are harvested later in the season are denser and hold up well for a long period of time. That’s why Gold Rush taste great right now, but Jonathan are often very soft and may begin rotting from the inside by March or April. Every variety has a different chemistry and thus ripens at a different rate. But, for varieties that keep well, it is reasonable to store them until March or April after the harvest.
How can I buy apples in the grocery store in July?
There are several answers to this question. Some of them are grown in countries in the southern hemisphere that have a growing season opposite of ours. Large commercial orchards in the US use what’s called Controlled Atmosphere Storage (CAS) to allow them to keep the apples until you are ready to eat them in July. What is CAS? The US Apple Association has a good description on their website:
“Remembering that apples take in oxygen and give off carbon dioxide, in 1940 Dr. Robert Smock of Cornell University experimented with reducing oxygen and increasing carbon dioxide in storage facilities, resulting in the development of a new storage technology called controlled atmosphere (CA) storage. CA storage requires air-tight, refrigerated warehouse rooms that are sealed after the apples are placed inside. The oxygen content in the storeroom air is reduced from 21% to 2.5%, and the carbon dioxide level is increased from 0.25% to 2-5%, and high humidity is maintained.”
“The CA process radically reduces the ripening process, thus allowing us to provide great-tasting U.S. apples year-round. Since CA storage is more costly per bushel, only the very best apples are put into this type of storage. CA storages are opened and converted to regular cold storage rooms usually after the first of the year, depending on demand and supply conditions.”
Although CAS has become necessary in today’s world to allow consumers to purchase apples all year, at Tuttles and most local orchards you will find only refrigeration and not Controlled Atmosphere Storage. It is very costly technology, and is used only at very large scale commercial orchards.
At Tuttles, we enjoy appreciating what’s fresh in the current season. So, in the summer when we don’t have our own apples we can enjoy strawberries or peaches or other fruits.