Correctly Cooling and Storing Pumpkins After Harvest

It’s fall and that means one of America’s most popular crops, the pumpkin, is in season. Pumpkins are extremely popular as carved jack-o’-lanterns for Halloween, as festive decorations all fall long, and of course as tasty holiday treats such as pumpkin pie. As with most food crops proper storage and handling of pumpkins after harvest is essential to maintain good quality, nutrition, and appearance. Let’s take a look at some interesting facts about pumpkins as well as key cooling and storage considerations and methods.

General Facts About Pumpkins

Pumpkins are a particular cultivar of the squash family. They are native to North America but are now grown worldwide for their taste, decorative use, and recreational potential. Pumpkin carving contests are popular around Halloween and “pumpkin chunking” is also becoming a yearly tradition throughout the country. In the US the term “pumpkin” refers specifically to the large, orange winter cultivar of squash that has come to be associated with Halloween. However, in other parts of the English speaking world “pumpkin” may be used interchangeably with “squash” or “winter squash.”

Pumpkins seeds are a popular, nutritious treat that is often consumed similarly to sunflower seeds. The pumpkins themselves often end up in pie and other sweet desserts. However, some cultures also eat pumpkin as a savory vegetable, though technically the crop is classified as a fruit. Pumpkin seed oil is also used as a salad dressing or for cooking. Finally, pumpkin may be used as an animal feed stock.

General Information About Cooling and Storing Pumpkins

The good news is that pumpkins are a relatively hardy crop and their thick rinds protect them from many types of damage. However, there are still a number of important considerations to bear in mind when it comes to harvesting, transporting, and storing pumpkins. Failure to follow good practices can result in premature fruit decay, loss of quality and value, and deterioration of appearance. Consider the following:

Harvesting – Pumpkins should be harvested once they reach a uniform orange or deep yellow color. By this point their skins should also have thickened and hardened and they should not be able to be punctured with the thumbnail.

Pre-cooling – Pumpkins should be moved out of direct sunlight after they have been harvested. Subjecting the pumpkin to a cold water drip for about 4-6 hours will also help maintain the quality of the fruit.

Curing – Pumpkins should be cured at a heat of about 80-85°F for about 10 days. During this time relative humidity levels should remain about 80-80%. Curing will help ripen any immature fruit, repair some superficial damage, and thicken and harden the rinds.

Temperature – Once curing is complete the pumpkins should be stored at a temperature of about 50-55°F. Pumpkins are sensitive to chill damage and should not be subjected to prolonged cooler temperatures.

Relative Humidity – After curing and during regular storage pumpkins should be kept at a relative humidity of about 50-70%. Lower relative humidity could result in the fruit shriveling and drying out. Higher relative humidity will promote fungal growth and decay.

Ethylene – Like many fruits, pumpkin are sensitive to ethylene gas exposure which will hasten ripening and decay. For this reason pumpkins should not be stored with other ethylene-producing fruits like apples. Likewise, over-ripe pumpkins should be removed from the rest of the pumpkins to prevent the same problem.

Storage – Pumpkins should be stored with plenty of space for air flow between them. They should not be stored so close that they are touching.

Shelf Life – Under optimal conditions pumpkins can last a lengthy 2-3 months after harvest. Pumpkins are sometimes canned or used in purees which of course dramatically increases consumable shelf life.

Methods of Cooling Pumpkins

Pumpkins should be cooled using the room cooling method in which they are placed in a chilled room with the temperature and humidity levels correctly set. Pumpkins should remain dry and well ventilated to discourage moisture buildup, which promotes fungal growth. If they are allowed to be wet, such as during pre-cooling, then they should be thoroughly dried before curing or prolonged storage. SEMCO/SEMCOLD LLC manufactures and supplies dependable, fully customizable cooling and storage systems. These systems are ideal for pumpkins, squash, and other produce.