How does climate change affect food security? – Processing

This is Clementina Barajas, I first met her while I was working with Engineers Without Borders Colombia.


Clementina offers her vegetables at the local farmer’s market every Sunday morning. She almost always sells out because her produce is popular because it’s pesticide-free and grown with water that runs down from the mountains. I know people who get up very early just to get to her stand first and take home the best produce while it’s fresh. If you get to the market by, let’s say, 11 am, tough luck. There’s either nothing left or what’s left is wilted and goes to the compost post. Her vegetables have high demand not only in her town, but in Bogotá, the capital of Colombia, which is two hours away by car. Unless you have the time and patience to endure a traffic jam to enter and exit Bogotá and reach her farm directly, (I’ve done this), you’ll miss out on these greens.

Clementina can sell more, she wants to sell more, there is demand for her produce, but, wilting happens fast and nobody likes yellow, smelly spinach in their salad.

How does climate change affect food security? – Part 2: Processing

(Read introduction to series here)

Case: Global average temperature rise and the cold-chain

a) Climate change effect

Can you guess which food processing technique is directly impacted by climate change? Here’s a clue: climate change is associated with a rise in average global temperatures.

Any guesses?

Freezing and refrigerating!

We freeze and refrigerate food to change its sensory properties (i.e. ice-cream), to transport it more easily (i.e. supplying demand), to extend shelf-life (i.e. frozen berries), but also, because our food is susceptible to changes we might not want, like browning on apples or mould on strawberries, we freeze and refrigerate foods to slow down the rate at which food changes. Click here to learn more about food processing.

b) Direct and indirect consequences

When you open your fridge and pull out frozen peas for dinner, your fridge is the last link in what is known as the cold-chain. Peas were picked from a field, taken to a processing plant, separated from their pods, frozen, packed and transported to grocery stores where you opened a big freezer, bought them and quickly carried home to store in your own fridge. That is the cold-chain.

Growing vegetables takes a lot of resources: water, fertilisers, time, people, etc.; imagine all that effort wasted because environmental conditions spoiled food before it reached our stomachs. Or worse, imagine the rise in human and animal disease because of toxins in what we eat. Mycotoxins are substances produced by fungi that can be present in food and have potential to cause death and disease in humans and animals. Mycotoxin growth is predicted to increase under warmer conditions associated to climate change (E. Van de Perre & L. Jacxsens, N. Deschuyffeleer, F. Devlieghere, 2010).

That’s why we need the cold-chain. But! The chain is cold and the planet is, on average, warming. Since the energy required to create a temperature difference between two environments is proportional to the difference of temperatures between the environments (think about a mini-fridge in the dessert), increased pressure to the cold-chain as a result of a warmer environment translates into a higher energy demand. According to James & James (2010), the cold-chain contributes to 1% of CO2 production in the world and 15% of electricity consumed world-wide is used for refrigeration.

 c) Impact on food security

1As I mentioned in this post, food waste is widespread. Developed countries tend to waste food at home and developing countries tend to waste food post-harvest because heat and humidity increase rate of unwanted changes in food. As the Institution of Mechanical Engineers (2013) report mentions, in warmer places like India and Africa, fruit and vegetable post-harvest loss ranges from 35% to 50%, annually.

People are moving further away from where food is grown (urbanisation trend), the cold-chain plays a vital role in reducing food safety issues and post-harvest waste (FAO, 2008). According to the International Institute of Refrigeration (IIR, 2009), loss of perishable foods is 14% higher in developing countries compared to developed countries due to lack of refrigeration.

In short, how does climate change affect food processing?

Public health problems due to food-borne diseases and food waste could become more frequent.

d) Lessons learned

We need to improve our cold-chain in a warming world or, face the food waste and safety consequences (Kirezieva, Jacxsens, van Boekel, & Luning, 2014). As our environment gets warmer, we must optimise energy efficiency in cold-chains and extend infrastructure in developing countries. Strengthening local trade to reduce the time and distance food travels can also reduce the need for the cold-chain.

I’m curious to know if you store all your fruits and vegetables in a freezer at home. Feel free to comment in the section below or to e-mail me at

Read more from the series How does climate change affect food security?:

Growing food takes a lot of resources: water, fertilisers, time, people, etc. Imagine all that effort wasted because environmental conditions spoiled food before it reached our stomachs. Or worse, imagine the rise in disease in humans and animals because of toxins in food. Mycotoxins are substances present in food, which are produced by fungi and can cause death and disease in humans and animals. Mycotoxin growth (i.e. mould on food) is predicted to increase under warmer conditions associated to climate change.