Refrigeration in the Ice Cream Industry: Technology, Efficiency and Control to Preserve Quality

Ice cream sales in Spain are estimated to be growing at a rate of 13% in value terms and 8% in volume, according to an article published by ElEconomista.

In ice cream manufacturing, refrigeration is not merely a preservation system; it is an active part of the production process. Temperature, freezing rate, air circulation and thermal stability directly determine the product’s texture, creaminess, resistance to melting and shelf life.

For this reason, a refrigeration system for the ice cream industry must be designed around the entire production process, rather than solely around cold-room temperatures. The plant must be capable of meeting simultaneous demands: cooling the mix, ageing, continuous freezing, rapid hardening, storage of the finished product and air conditioning of production areas.

Refrigeration as a Technological Ingredient in Ice Cream

Ice cream is a complex structure consisting of frozen water, a concentrated liquid phase, fat, proteins and incorporated air. During manufacturing, the aim is not simply to reduce the temperature, but to control how ice crystals form and how the emulsion is stabilised.

The industrial process normally includes mixing, pasteurisation, homogenisation, cooling, ageing, dynamic freezing, forming, hardening and storage. After pasteurisation, the mix must be cooled rapidly to the ageing temperature. As a technological guideline, it is kept below 5 °C for at least four hours, promoting the hydration of proteins and stabilisers and the partial crystallisation of the fat. Insufficient ageing may cause difficulties with air incorporation, texture defects and faster melting.

Continuous freezing is the core of the process. Inside the freezer, the mix is cooled while being agitated and aerated, forming a semi-fluid structure. Approximately half of the water may be frozen at the freezer outlet, meaning that the product still requires a subsequent hardening stage.

Fast hardening: the key to a fine texture

Ice crystal size is one of the main indicators of quality. Fast freezing produces small crystals and a creamier mouthfeel, whereas slow heat removal promotes the formation of larger crystals and a coarser texture.

The hardening tunnel must provide very low temperatures, high air velocity and uniform air distribution over the entire product. In industrial processes, the air temperature may be around –40 °C. The aim is to quickly increase the frozen water fraction and reduce the time during which the ice cream remains within a critical temperature range. On certain production lines, hardening is considered complete when at least 80% of the water is frozen. 

Installing a high cooling capacity is not enough. The design must prevent airflow short-circuiting, dead zones and temperature differences between trays, racks or product levels. Evaporator selection, air throw, available fan pressure and the defrost system are just as important as the rated cooling capacity.

INTARCON’s KV series wall-mounted evaporator units are designed for freezing tunnels, with high-airflow fans and high available pressure, configurations adaptable to racks, and versions prepared for different refrigerants.

Multiple Temperatures, One Factory

An ice cream factory has very different load profiles. Preparation and ageing areas operate at positive temperatures; storage rooms operate at low temperatures; and continuous freezers or hardening tunnels require even more demanding evaporating temperature levels.

This diversity makes it necessary to study the refrigeration architecture carefully. Options include indirect systems using glycol or brine, direct-expansion compressor racks, CO₂ systems with several suction levels, low-charge ammonia plants, or hybrid solutions that separate process cooling from the refrigeration used for cold rooms and tunnels.

The best configuration depends on the required cooling capacity, load simultaneity, evaporating temperatures, outdoor climate, factory layout, process criticality and future expansion possibilities.

Indirect R290 Systems: Flexibility and low refrigerant charge

In process applications, indirect systems allow the primary refrigerant to remain contained within a compact plant, while cooling is distributed using glycol or brine. This solution facilitates the supply of refrigeration to ageing tanks, heat exchangers, production areas and air coolers, reducing the amount of refrigerant circulating inside the factory.

INTARCON’s intarCUBE R290 and intarWatt R290 plants are designed to produce chilled water, glycol or brine with a low propane charge. The Full INVERTER versions modulate compressor capacity and adapt cooling output to variable demand, which is particularly beneficial when shifts, batches and the number of operating lines change.

This modulation reduces starts and stops, improves supply temperature stability and can lower energy consumption during part-load periods. Certain configurations also allow heat recovery to produce hot water for cleaning, auxiliary services or preheating.

CO₂ for integrating positive and negative temperature refrigeration

When the installation combines storage rooms, freezing areas and other low-temperature services, a CO₂ compressor rack can centralise refrigeration production and reduce direct environmental impact.

INTARCON’s ECO₂Watt range includes transcritical compressor racks with single or dual suction, an integrated gas cooler and configurations designed to serve positive and negative temperature applications simultaneously. Parallel compression helps improve energy performance at high outdoor temperatures.

In an ice cream factory, this architecture can integrate raw-material storage rooms, finished-product storage, anterooms and tunnels, provided that pressures, oil management, defrosting and evaporator control are designed correctly.

Low charge ammonia for high refrigeration loads

In higher-capacity factories, ammonia continues to be a benchmark due to its thermodynamic properties. Today’s packaged solutions make it possible to reduce the refrigerant charge and confine the refrigerant to outdoor or technical areas.

INTARCON’s ammolite NH₃ chiller is designed for medium- and low-temperature industrial applications, with air-cooled condensation, variable-speed screw compressors and a reduced R717 charge. It can supply indirect glycol or brine circuits serving processes, cold rooms or hardening systems.

The choice between R290, CO₂ and NH₃ should not be based solely on the refrigerant. Seasonal efficiency, total refrigerant charge, capacity, maintenance, safety, process temperature and life-cycle cost must also be compared.

Efficiency, Defrosting and Service Continuity

The refrigeration demand of an ice cream factory is variable and includes peaks associated with product intake, freezing, door openings and defrost cycles. An efficient design must take part-load operation into account, rather than considering only the rated operating point.

The most relevant measures include capacity control using variable-speed drives, EC fans, floating condensing pressure, adjustment of the evaporating temperature, variable flow in hydraulic circuits, heat recovery and coordinated defrost scheduling.

A frosted coil loses capacity and increases energy consumption. However, excessive defrosting introduces unnecessary heat into the cold room. The strategy must be adapted to the humidity level, air infiltration, fin spacing, evaporator type and operating conditions.

It is also advisable to divide the installation into independent sections and provide redundancy. In ice cream production, a breakdown may stop production lines, compromise entire batches or cause losses in finished-product cold rooms.

Monitoring: Turning Data into Quality

Continuous monitoring makes it possible to correlate refrigeration system performance with product quality and energy consumption. Temperatures, pressures, superheat, valve opening, defrost times, energy consumption and alarms provide essential information for anticipating deviations.

The kiconex  system used by INTARCON enables refrigeration installations to be monitored, historical data to be consulted, energy consumption and performance to be analysed, and alarms to be managed in real time. In an ice cream factory, this information helps detect performance losses or temperature deviations before they affect the production process.

A Solution Designed Around the Product

The ice cream industry requires precision during ageing, capacity during freezing, speed during hardening, stability during storage and continuity throughout the entire production season.

INTARCON can meet these requirements through R290 chiller plants, indirect glycol or brine systems, CO₂ compressor racks, low-charge ammonia solutions, and evaporators for production areas, cold rooms and tunnels. Its technical advisory service analyses refrigeration requirements, regulatory constraints and actual process operating conditions to select an efficient, reliable and sustainable solution.

Ultimately, refrigeration design must begin with one question: what does the ice cream require at each stage to preserve its structure and quality? When the installation is designed around the answer, refrigeration ceases to be an auxiliary cost and becomes a tool for productivity, differentiation and product control.