Avocado Life Cycle & Food Waste
February 19, 2020 Silvia Lazzaris By Silvia Lazzaris My Articles

Avocado Life Cycle & Food Waste

Besides rodent and insect bites, fungi and plant diseases, human mishandling is one of the main causes of avocado waste.

Just to give you an idea, out of the 81,000 tonnes of avocados produced in Kenya in 2017, 30,000 to 40,000 tonnes went to waste due to pre- and post-harvest handling practices - in other words, half of the avocados produced went to waste because workers touched them the wrong way.2 To understand how we lose avocados that would be otherwise perfectly healthy, let’s have a look at the avocado life cycle and the many stages and people involved in the life of the fruit.

Stage 1. Avocado trees are born in nurseries, by the hands of farmers that take a bud from one plant to grow another.

Stage 2. When avocado babies are strong enough, they are planted 7-10 metres from one another.

Stage 3. Avocados are grown. It takes about 8 years for a new avocado tree to become a fully productive, adult tree making 80-100 kg fruit per year.

Stage 4. When fruits are mature but still hard, farmers pick them by hand or with the help of a hook that makes the fruits fall to the ground. Special machines then size them, clean dirt off them, and sort them for different markets.

Stage 5. The fruits embark on often long and perilous journeys, especially if they come to Europe from South America. Avocados travel a couple days in a truck, another two weeks in a cargo ship (for example on the Manzanillo - Panama - Europe route) and a few more days to a packaging warehouse.

Read avocado production's environmental and social impact.

Bruised avocados from handling

Loss happens because, along the way, avocados are often touched by workers who haven’t received any training on how to best handle them, especially during travel and packing stages of the avocado process. “It’s hard to do everything properly so the fruit arrives at the other side of the Ocean in good quality, and then have someone on the other side who knows how to handle them and knows what they are doing. We’re still on a learning curve. This is still a huge challenge,” says Dr Arpaia, Subtropical Horticulturist at the University of California, Riverside.

Mishandling happens especially during transport and packing processes: simply holding an avocado with too much pressure (or, in the worst cases, dropping it onto the ground) will produce a fruit too soft, or a perfect-looking one that is actually rotting inside. Mishandling avocados can also cause their skin to break: once their protective layer is gone, the fruits are exposed directly to the environment, including bacteria and oxygen, which ultimately make the fruit rot faster.

Avocados are damaged during transport

Travel can damage avocado too, and not only because moving the fruit around too much could cause it to bruise. In cargo ships, avocados are kept in controlled atmospheres, with higher carbon dioxide and lower oxygen slowing the ripening process - in a way, putting the fruit to sleep to not make it ripen too early. However, avocado is a subtropical fruit: this means that it is sensitive to chill injury  - an alteration of the fruit’s internal metabolism - when exposed to temperatures too low.1 The signs of chilling injury in avocados are clearly seen only when the fruit is ripe - this means that the disease often goes unnoticed until consumers, to their chagrin, open foul tasting and smelling fruits.

Less avocado waste in Europe?

Although Spain is the main producer of avocados within Europe, the main suppliers to the European market are still very far countries: Peru, followed by Chile, South Africa, Israel, Mexico and Kenya. However, pilot programmes for avocado production are being run in Portugal, Italy, and Greece.3 The growth of European local markets could bring many benefits, resulting in shorter journeys, fewer passages in the supply chain and, hopefully, less waste.

What to do with an avocado not ripe enough?

Dr Arpaia suggests to refrain from the temptation to open it to see if it is maybe ripe. If it’s not soft enough, we shouldn’t open it - otherwise it will never ripen and we will have wasted it. Instead, we could put it at room temperature in a brown paper bag with an apple. Apples are good producers of a hormone called ethylene - this hormone, produced by the apple, will help the ripening of the avocado sitting next to it!

February 19, 2020 Silvia Lazzaris By Silvia Lazzaris My Articles
 

References

  1. Dorantes, Parada, Ortiz (2004). Avocado: Post-Harvest Operation. Report by the Food and Agriculture Organisation of the United Nations, FAO. Rome, Italy.
  2. Wasilwa, L.A. Njuguna, J. K. Okoko, E. N. (2017) Status of Avocado Production in Kenya. Kenya Agriculture Research Institute. Poster published on ResearchGate.
  3. Europe Poised for Avocado Growth (2019). Eurofruit. Accessed on 10 January 2020.