CRYOFOOD

Innovative system prototype for the rapid freezing of food products at very low temperatures

Description

Development and construction of an innovative system prototype for the rapid freezing of food products at very low temperatures (-80/-100 °C) based on a single-phase air (or other natural gas) cycle
To achieve and maintain increasingly high quality standards for frozen foods (in terms of organoleptic and nutritional properties), freezing times must be rapid to prevent the formation of large ice crystals. For many types of food products, the reduction of freezing times can only occur at process temperatures much lower than those currently used in industrial freezing processes (around -40 °C). Currently, low-temperature freezing processes rely on the direct evaporation of liquid nitrogen or carbon dioxide, resulting in very high energy and logistics procurement costs.

Result to be enhanced

Reverse Brayton thermodynamic cycles, of the bootstrap type, are a type of system widely used for very specific applications, such as air conditioning in aircraft or high-speed trains. Within the project, the goal is to develop a prototype freezing system based on this technology. The project involves creating a system (Brayton cycle + freezing chamber) that is unique in its kind.
Both the Brayton cycle and the chamber must be appropriately modified and recalibrated in terms of layout, components, and connections between the various system parts. Additionally, an anhydrous working fluid will be employed to prevent condensation and frost formation within the components.
The working fluid’s temperature levels (< -80 °C) and pressure (> 8 bar) have been optimized for the process, including the selection of some system components to maximize energy efficiency and reliability. Such a low-temperature freezing system will offer lower energy consumption and more advantageous logistical costs compared to liquid nitrogen or carbon dioxide (consumable) systems.

Why is it important?

The project’s objectives are fully aligned with the thematic area of product/process innovation, food safety, packaging, and shelf life. The work involves the design and construction of a prototype plant for the rapid freezing of food products, developing an innovative solution that incorporates a high-efficiency thermodynamic cycle, without the use of potentially hazardous technical fluids for the environment, and without the use of liquid nitrogen, but exclusively utilizing a natural gas such as nitrogen or dry air. This represents a process innovation that has evident benefits regarding food safety and the shelf life of treated products. The primary beneficiaries of the proposed innovation will be the food processing companies involved, who will benefit from the production and commercialization of the new system once engineered, as well as all food companies that produce and market frozen products.