Effective Storing and Cooling of Bananas
Bananas are a popular dessert fruit and cooking starch all over the world. However, they are typically grown in tropic and subtropic regions and must thus be shipped to consumers in cooler climates. This makes proper storage and cooling a major consideration since the process often requires the fruit to spend long times in cargo containers. Let’s take a look at some facts about bananas and their varieties, the difference between bananas and plantains, uses for bananas, and factors that affect optimal banana cooling and storage.
Banana Facts, Varieties, and Terminology
All bananas and plantains belong to the scientific genus Musa and most modern seedless bananas are cultivars of the species Musa acuminata or the species Musa balbisiana. Botanically bananas are considered a berry and while many people think of banana plants as being trees due to their large size, they are in fact herbaceous plants. Bananas have no true trunk or stem, but rather have psuedostems that consist of tightly packed leaves. Banana plants range in height from about 10 feet tall to about 23 feet tall, with most cultivars averaging around 16 feet tall. They are perennials which die off every year, but leave behind offshoots capable of propagating the species. Different varieties may have yellow, green, brown, red, or purple rinds.
In the Europe, the United States, and the rest of the Americas the term “banana” is commonly used for the dessert variety that is eaten raw, while the term “plantain” is commonly used for the starchier variety that is used for cooking. However, many more varieties of bananas exist in Southeast Asia and the Pacific Islands and as such there is more overlap between the two and native languages don’t distinguish between them.
The term banana is believed to have originated from the Wolof language of west Africa which uses the word “banaana.” From there it entered English via Spanish or Portuguese.
The Many Uses for Bananas
Bananas are commonly eaten as dessert fruit or blended into smoothies, juices, and ice cream as flavoring. They may also be dried and eaten in foods like granola or used to create banana bread. They are often used in cooking where they represent a significant source of starch for many cultures and cuisines. They may be thinly sliced and fried or baked into banana chips or even fermented into banana beer.
In addition to their use as food, banana leaves are sometimes harvested to make textiles, paper, and other household fabric uses like table cloths. Banana fibers are even used for making Japanese kimonos. Finally, they are also appreciated as a decorative plant.
General Information About Cooling and Storing Bananas
Bananas that ripen on the tree only have a shelf life of about 7–10 days. However, this is generally considered too short a shelf life to be viable for mass market exportation. As such bananas are instead picked green, kept from ripening by careful storage methods, and artificially ripened once they reach their destination.
Temperature – Bananas are typically stored at about 56°F-58°F for long-term storage and transport. Once they are ready for ripening they are warmed slightly to about 59°F-68°F. Bananas should not be subjected to temperatures below 55°F because they are very susceptible to chill damage with green fruit actually more vulnerable than ripe fruit.
Relative Humidity – Optimum relative humidity is about 90%-95%.
Handling – Bananas should be very carefully handled. Dropping them, scuffing them, or bruising them will damage the fruit, could contribute to water loss, and may also cause premature decay.
Shelf Life – The shelf life of bananas will vary significantly based on harvest conditions and storage conditions. Tree ripened fruit only lasts about 7-10 days while fruit picked green and cooled and stored correctly typically lasts about 3-4 weeks. Bananas that undergo controlled atmospheric conditions may even last up to 40 days, or almost 6 weeks.
Controlled Storage Conditions for Bananas
Ethylene is the primary banana ripening agent and plays an extremely important role in commercial processes. Green bananas are often picked, placed and stored in polyethylene bags with carbon dioxide levels raised to about 5% and oxygen levels lowered to about 2%. They are also often stored with potassium permanganate. When ethylene is released by the bananas during storage, it is absorbed by the potassium permanganate thereby preventing ripening.
Once the bananas reach their intended market they are artificially ripened by exposing them to ethylene for about 24-48 hours. The rind of ripe yellow bananas will rapidly develop black spots and brown. However, the fruit inside remains unaffected and suitable for consumption for longer. Fruit that are still partially green when purchased may be ripened more rapidly in-home by placing them in paper bags overnight with high-ethylene producers like apples or tomatoes. SEMCO/SEMCOLD LLC designs high quality produce cooling and storage systems that will help keep bananas fresh and delicious.
