Put hard pears in a tightly closed paper bag: The gas they naturally release gets trapped inside and speeds up the ripening process that takes 7-10 days

Are the pears you purchased so tough they resemble stones? Well, there is nothing wrong with your purchase. Most pears available in the US market are deliberately picked while still firm and are meant to mature only after they are plucked from the trees. Here's one secret that can speed up pear ripening at home. Place the pears in a sealed paper bag, and the gas released by the fruit will accumulate in the sealed area, pushing the fruit to ripen within seven to ten days instead of waiting indefinitely on your kitchen countertop, as suggested by the Iowa State University Extension and Outreach. This home trick has a simple biological explanation.

The real reason store-bought pears are rock hard

Unlike peaches or plums, most pear cultivars available in grocery stores across America, such as the common Bartlett pear, are deliberately harvested when they are hard and green. According to Iowa State University Extension and Outreach, pears that mature while still on the tree become gritty as stone cells develop within the fruit, and their taste becomes poor as well. Farmers pick the fruit once the skins turn from dark green to light yellow-green and let it ripen after harvest. This is quite different from how most people treat other kinds of fruit. When it comes to pears, you do not want them to be soft when you buy them.

The gas trapped inside the bag does the real work

Pears, like other fruits, can be induced to ripen after harvesting by ethylene gas, an important naturally occurring hormone in plants. The fruit produces minute quantities of this hormone as it ripens, and the gas builds up in a closed bag. If left in the air, the fruit loses ethylene. But when the fruit is enclosed in a paper bag, the gas has nowhere to go. Hence, it accumulates near the fruit and triggers rapid ripening, as explained in the USDA Agricultural Marketing Service Technical Report on ethylene and fruit ripening. Pears are not the only fruits that react to ethylene gas; bananas, mangoes, and tomatoes also ripen when exposed to this gas, as stated in the USDA Agricultural Marketing Service's Ethylene Handling/Processing Technical Report, which lists ethylene products as labeled in the US for ripening avocados, bananas, kiwis, melons, mangos, papayas, pears, persimmons, pineapple, stone fruits, and tomatoes: Getting the bag method right

Getting the bag method right

The process itself only requires a few seconds. Don’t use a plastic bag when you want to store your hard pears. Instead, use a paper bag, because a plastic bag retains moisture and creates conditions favorable for mold development instead of ripening. Close the bag so the gas stays inside, and leave it at room temperature (60 to 70 degrees F), according to Iowa State University Extension and Outreach. Check the pears daily by applying slight pressure near the stem.

Not ready to eat them yet

If you do not plan to eat the fruit right away, refrigerate it; this will not interfere with the ripening process described above. Unripe pears should be kept under refrigeration at temperatures between 32 and 35 degrees Fahrenheit and can last one to three months, as per Iowa State University Extension and Outreach. Cold storage is not just a temporary fix, either. A Foods article by post-harvest scientists Robert K. Prange and A. Harrison Wright says most European pear varieties need near-freezing temperatures to trigger an ethylene response needed for proper ripening, published in Foods. The process is simple: refrigerate the pears until about a week before eating, then move them to a room-temperature paper bag, as recommended by Iowa State University Extension and Outreach.

One exception worth knowing before you bag every pear

There are a few exceptions. Asian pears, also known as apple pears, should be left on the tree until fully ripe and should not be harvested early, or the desired effect cannot be achieved, says Iowa State University Extension and Outreach. The paper-bag method works best for European pears such as Bartlett pears.

The simple fix for hard pears every time

You can do all of this without special devices or even a trip to the supermarket. All you need is a paper bag and a few days, along with an understanding of what happens in that enclosed environment. Once you understand the science, those hard pears will make sense at checkout because they are only the first stage of a longer ripening process.