# Use of Phase Change Materials for Food Applications--State of the Art in 2022
## 2 Food Applications of PCM
### Food Processing
#### 2.1.2 Multi-Purpose Cold Storages for Various Cooling Applications  
In the food industry, cooling is e.g., needed in slaughterhouses, generally meat industry, dairy industry, central kitchens, breweries, and bottling plants. Cooling is to a large degree used for food preservation, by refrigeration and even freezing, but also otherwise in food processing, for example to make ice cream. Cooling in general refers to any type of cooling, independent of temperature. For cooling to temperatures below ambient temperature electrically driven compression coolers, called chillers, are commonly used. If the demand for cold by the production process is fluctuating, it is often more economic to size the cooler/chiller not to the maximum demand, but just to the average demand and cover the peak demand by cold stored in a cold storage. Cold storage also allows producing cold at higher energetic efficiency, usually at night when due to the lower ambient temperatures, maybe also at lower cost, when cold production is shifted to electricity price off-peak times. And a cold storage also can serve as a backup. The same situation exists in process cooling e.g., in the pharmaceutical and chemical industry, and air-conditioning of buildings. Consequently, the same technical solution of combining a cold storage with an electrically driven cold production unit (cooler/chiller) is used in many places for different purposes. The technologies for cold storage use mainly cold-water storage as sensible heat storage, and ice storage using the phase change of water. While cold-water storage is useful only for cooling well above 0 \({}^{\circ}\)C, cooling at temperatures just a few degrees above 0 \({}^{\circ}\)C is done by ice storage using water/ice as PCM, while at temperatures below 0 \({}^{\circ}\)C usually eutectic water-salt solutions are used. For high cooling powers, mixtures of water and ice (called ice slurry) that can be pumped are used, sometimes ice is even added directly to a process. Generally, PCM compete with other technologies, primarily cold-water storage. The low price of water makes the economics of ice storage comparatively easy. It is therefore not surprising that the use of ice storage is widespread, not only in building applications like air conditioning and district cooling, but also for industrial applications. A variety of technologies exist which can basically be split up in two groups, one where the ice is produced and used in a storage compartment, and heat exchange is by a heat transfer fluid via a heat exchanger or by direct contact with the ice, and a second group where ice is produced as small or larger particles which can be used for cooling directly. The market for the first is occupied by many companies, ranging from big to medium and small ones. Some of them are already active for several decades. A brief description of the technologies used, estimation of the worldwide installed capacity of cold storage with ice, and its effect in the electricity grid has [3]. Well-known companies producing ice storages are for example BAC, Calmac, and Cristopia (subsidiary of CIAT), EVAPCO, or FAFCO. Installation examples can be found on the websites of BAC [6], mentioning specifically diaries, breweries, meat processing, wet air pre-cooling for storage of fruit and vegetables, Calmac [7], and Cristopia [8], mentioning specifically slaughterhouses and meat industries, central kitchens, bottling plants, dairy industries, breweries. In recent years, the company Sunamp ([[https://sunamp.com](https://sunamp.com)]([https://sunamp.com](https://sunamp.com)), accessed on 1 December 2022) has developed, and now markets PCM TES. Starting the business with storages for space heating and domestic hot water, using PCM of phase change temperature at 58 \({}^{\circ}\)C, now also storages to freeze (\(-\)30 \({}^{\circ}\)C), refrigerate (5 \({}^{\circ}\)C), and even sterilize (118 \({}^{\circ}\)C) are available, with storage capacities ranging from 3 kWh to 12 kWh for domestic applications, and 80 kWh for industrial applications.