Keeping food cool

Refrigerants are an essential for reaching the UN SDGs

By Natalie Mouyal

Bananas from Guatemala and beef from Argentina were once considered exotic delicacies to Europeans and North Americans. But how is such foodstuff transported from one port to another without having it spoil during the journey?

The solution was devised by the French engineer Charles Tellier who fitted the first ship with a refrigeration system that allowed meat to remain fresh during its 105 day journey between France and Argentina in 1876. Refrigerated shipping emerged and, by 1902, 460 refrigerated ships, or “reefers” as they were also known, transported millions of tonnes of Argentina's beef and Guatemalan bananas.

Picture of a commercial refrigeration unit inside of a store Refrigeration is necessary to prevent food spoilage (Photo: StockSnap from Pixabay)

From producer to consumer, food must be kept at low temperatures to prevent spoilage and slow the growth of harmful bacteria. A reliable cold chain begins the moment food is harvested through to the processing and packaging of the product until it reaches the retailer and, finally, the consumer. Throughout the process, food must be kept cold, including during its transportation and storage.

The International Institute of Refrigeration (IIR) estimates that about 400 million tonnes of food are preserved using refrigeration worldwide and over two billion refrigeration units - commercial and in homes - are in use. But more effort is needed. According to the Food and Agricultural Organization (FAO), approximately 1,3 billion tonnes of food is wasted or lost each year. In developing countries, loss is often the result of technical constraints, such as the lack of an uninterrupted cold chain.

A reliable cold chain is necessary to achieve food security and end food waste in many parts of the world. While many IEC Standards help to promote the United Nations’ Sustainable Development Goals (SDGs), the standards related to cooling and refrigeration are essential to helping countries achieve SDG 2 on ending hunger.

Refrigeration is also essential for healthcare. During the Second World War portable cooling units were used to preserve blood, medicine and food for use at army hospitals and on open battlefields. Today, refrigeration is used to properly conserve medicines and vaccines. It is necessary to achieve SDG 3 on ensuring healthy lives and well-being.

The need for refrigerants

Refrigeration can be defined as the lowering of the temperature in an enclosed space by removing the heat from the space and transferring it elsewhere. However, heat will not spontaneously move from a colder location to a hotter one. Liquid refrigerants are necessary to absorb and remove the heat from the space.

Refrigerants have a key role on the performance of the refrigeration cycle. However, some of the most commonly used refrigerants contain chlorine which, when released into the earth’s stratosphere, cause harm to the ozone layer.

Worldwide efforts to reduce the use of substances responsible for depleting the ozone layer led to the adoption of the Montreal Protocol in 1987. Considered by some to be one of the most successful international agreements, the Montreal Protocol has allowed the ozone hole in Antarctica to become smaller However, the Protocol also led to the replacement of certain substances with hydrofluorocarbons (HFCs) that may not damage the ozone layer but are considered greenhouse gases with the potential to cause global warming.

The Kigali amendment to the Montreal Protocol, which entered into force on 1 January 2019, requires countries to phase out the use of HFCs by more than 80% over the next 30 years. Low global warming potential (GWP) alternatives, so called natural refrigerants (carbon dioxide, ammonia and hydrocarbons), as well as unsaturated HFCs, are possible replacements to the presently used HFCs. However, apart from carbon dioxide, most of the low GWP alternatives are significantly more flammable than HFCs.

IEC Standards ensure safety and efficiency

IEC Standards ensure among other things, that products meet certain safety requirements. IEC Technical Committee (TC) 61 prepares standards on the safety of household electrical appliances, including for refrigeration. Its subcommittee (SC), IEC SC 61C prepares international safety standards for refrigerators, freezers and similar appliances used in homes, supermarkets, hospitals, transportation, manufacturing, etc.

SC 61C is currently in the process of updating the standard IEC 60335-2-89, which provides the requirements for commercial refrigerating appliances and ice-makers. The draft standard is available as a pre-release version awaiting the final approval by IEC members.

According to Marek Zgliczynski, Chair of SC 61C, “the draft standard will allow manufacturers to comply with present and future regulations of phasing out refrigerants with a high global warming potential for this market segment”. This includes most notably the large, commercial display cases used in supermarkets. These standardization activities seek to increase the safe use of natural refrigerants to help attain SDG 13: Climate action.

Other IEC Standards are also essential in ensuring the safety of refrigerating appliances. Most notably, a number of standards in the IEC 60335 series address the safety requirements for various types of appliances using refrigerants. For example, IEC 60335-2-104 provides the requirements for the recovery and/or recycling of refrigerants.

IEC SC 59M addresses the performance requirements of electrical household cooling and freezing appliances such as refrigerators and food freezers. In an attempt to measure the energy efficiency of household refrigerators, SC 59M issued IEC Technical Report (TR) 63061 which provides a uniform method for calculating the parameters of adjusted volume in refrigerating appliances. Performance testing methods for commercial appliances are covered by relevant ISO standards.

Gallery
Picture of a commercial refrigeration unit inside of a store Refrigeration is necessary to prevent food spoilage (Photo: StockSnap from Pixabay)
Picture of children holding up apples A proper cold chain can ensure that food reaches its final destination (Photo: Kevin Phillips from Pixabay)