Avocados are a delicious, versatile food enjoyed all over the world for their distinct taste and nutritional value. In the US they are often grown in Texas, California, and Florida and then transported to markets throughout the country. As with most fruits and vegetables care and handling during and after harvest go a long way toward ensuring that the avocado is in peak condition when it reaches consumers’ plates. What follows are some general facts about avocados, factors that affect their cooling and storage, and effective methods of cooling and storage.
General Facts About Avocados
It is a surprise to some people to learn that, botanically speaking, the avocado is a fruit, not a vegetable. In fact it is actually a type of large, single-seed berry. Avocados are grown on trees in tropical and subtropical climates throughout the world, particularly in Central and South America and the Mediterranean. They are believed to have originally developed in Mexico in the state of Puebla. From there they spread around the world and embedded themselves in the cuisine of numerous nations and cultures. They are sometimes eaten as a savory food in sauces, salads, with meat and sandwiches, or as side dishes. However, they are also popular ingredients in desserts, ice cream, milkshakes, and sweet snacks.
Avocados are a very nutritious, calorie-rich food. They have a much larger percentage of fats than most produce, making them an important dietary staple in many countries. Most of their fat content comes from monounsaturated fats, which have been shown to improve heart health by lowering triglyceride levels and LDL (bad) cholesterol, while simultaneously raising HDL (good) cholesterol levels. Avocados also contain more potassium by weight than even bananas and they are a good source of fiber. They are also rich in B vitamins, folate, and Vitamin E.
General Information About Cooling and Storing Avocados
Avocados share an unusual trait with bananas, in that unlike most fruits and vegetables they will not ripen while they are still on the tree. Instead they must ripen after they have been harvested. However, this does not mean that avocados can be picked at any time during their life cycle. They should be harvested when they reach optimum maturity level. Harvesting either too soon or too late will decrease both the quality and taste of the fruit as well as its shelf life. Factors that affect cooling and storage include the following:
Temperature – Avocados are particularly susceptible to chill damage and should not be over-cooled. Ideal temperatures will vary depending on the cultivar. The most popular cultivar, the Hass avocado which represents about 80% of all cultivated avocados in the world, does best with a storage temperature of about 41º-53ºF.
Humidity – Avocados contain a large proportion of moisture or “oil” and thus care should be taken to prevent them from drying out and shriveling. Fortunately their skins are well adapted to minimize moisture loss. For the Hass avocado storage humidity should be about 85-90%.
Shelf Life – The shelf life of avocados will vary significantly based on cooling and storage conditions as well as the maturity level of the avocado at the time of harvest. Typically they will last about 2-4 weeks. However, under optimal conditions the may last up to 8 weeks.
Ethylene – Like many fruits and vegetables avocados release ethylene gas as they ripen. The gas in turn further hastens ripening. This sensitivity to ethylene can be both a pro and a con for avocados. On the one hand storing them with ethylene-producing produce may unintentionally shorten their shelf life and should thus be avoided. However, because avocados are generally preferred fully ripe, or almost fully ripe, at market they are often intentionally exposed to ethylene once they reach their destination to make them more attractive to buyers.
Methods of Cooling Avocados
Hydrocooling – Hydrocooling involves rapidly submerging the avocados in near freezing water to quickly and effectively lower their temperature.
Forced-Air Cooling – Forced-air cooling is the process of placing the avocados in a refrigerated room, such as a cooler, and then pulling air through them as a means of forcing circulation. This cools the avocados much more quickly than room cooling alone.
Controlled Atmosphere Storage – Controlled atmosphere storage involves closely controlling the temperature, humidity level, oxygen level, and the level of many other key gases as a way of creating an optimal condition for the avocados. This is a very effective method and helps maximize the avocados’ shelf life and quality. However, it is also an intensive process that it only suited to large quantities of avocados.
Semco Is an Industry-Leader in Cooling Equipment
Semco is an industry-leader in cooling equipment and cooling systems ideal for use with avocados and other produce. We pride ourselves on excellence in customer service and in being able to customize each system to best fit the unique needs of each of our clients. Please contact us for more information about cooling systems for avocados.