Best Practices for Post-Harvest Cooling of Peas and Beans
Peas and beans are one of the most popular types of food in the US. They are often sold fresh, frozen, or canned and they are considered a staple by millions of Americans. However, in order for peas and beans to taste their best and offer the most nutritional value possible it is important that they be properly cooled and stored prior to consumption.
General Facts About Peas and Green Beans
Peas are considered a botanical fruit; however, they are commonly prepared and eaten as a vegetable. Peas are closely related to legumes and beans. Peas form in small pods that can be cracked open to attain the tender fruit. Peas have been consumed by human beings since the beginning of recorded history and as such there are a wide variety of different cultivars. The main ones we will be discussing are southern peas which include crowder peas, cream peas, and black-eyed peas to name just a few.
Like peas, beans are also actually considered a botanical fruit, but also like peas they are commonly prepared and eaten in ways similar to that of a vegetable. The term bean is typically used in reference to members of the leguminosae family. However, the term may also be applied to the seeds or pods of unrelated plants such as castor beans, cocoa beans, coffee beans, or vanilla beans, which simply bear a resemblance to true beans. Like peas, beans have also been consumed throughout recorded history. In this article we will focus primarily on snap beans, also known as green beans, and lima beans, also known as butter beans.
General Information About Cooling and Storing Peas and Beans
Respiration and Degradation – Peas and beans, like most other types of fruits and vegetables release heat as a result of respiration which then contributes to their degradation and loss of quality. Because of this it is important to begin cooling the peas and beans within at least 1-2 hours of harvest. The peas and beans should also not be left in direct sunlight while they are awaiting cooling.
Temperature – Peas and beans do best with a storage temperature of about 37 °F to 45°F. At higher temperatures the rate of respiration is faster which in turn leads to more rapid degradation and loss of quality. However, if the storage temperature drops below 31°F the peas and beans may be subject to freeze damage.
Relative Humidity – Peas and beans thrive at a cooling and storage relative humidity of about 95%.
Handling – To prevent damage and loss of quality it is important that peas and beans be handled carefully during harvest and storage.
Shelf Life – Depending on the storage conditions and the particular peas and beans they will typically have a shelf life of about 5 to 10 days.
Methods of Cooling Peas and Beans
Hydrocooling – An effective method for quickly and thoroughly cooling peas and beans is hydrocooling. This involves submerging the peas and beans in very cold water to rapidly remove heat and prolong shelf life. The water should be as near to freezing as possible while still remaining liquid.
Forced-Air Cooling – Basic room cooling is not a sufficient method of cooling peas and beans because it takes too long and pods located near the center of the container may never cool fully. However, forced-air cooling, which involves pulling cooled air through the peas and beans is about 8 times faster than room cooling alone, depending on the fans and load size, and is a very effective cooling technique.
SEMCO/SEMCOLD LLC is a leader in industrial cooling and freezing equipment. We can custom-build cooling systems designed to customer specs that are ideally suited for cooling peas and beans. Please contact us for more information.
