Improving the food safety and shelf life by high pressure CO2
This invention uses supercritical carbon dioxide (SC-CO2) to pasteurize food, at temperature and pressure conditions that do not alter its structure or flavour.
This invention is a new non-thermal pasteurization process (lower than 45°C). It allows the treatment of a food product that is inserted into a packaging, made of a material configured for containing a gas mixture that includes mostly CO2. Advantageously, an agent with antioxidant properties can be added to the mixture in the packaging, obtaining a synergistic effect for microbial inactivation. Hence, the type of gas mixture allows the pasteurization process, promoting the preservation of the food inside the packaging, thus extending the shelf-life of the packaged product. Moreover, this process can be even easily integrated into the standard food chain of ready to eat products, becoming an additional decontaminating process able to inactivate microorganisms at low temperature, maintaining the sensorial, chemical and physical characteristics of the fresh food. Additionally, it is performed with limited costs since the pressures involved are lower than 20 MPa and so, it does not require too much expensive equipment like those used in other standard technologies. In conclusion, it does not alter the molecules in fresh food, preserving the structure and texture of food products and prolongs their shelf-life.
The process allows a longer product shelf-life since it reduces the number of bacteria responsible for the spoilage of food, increasing food safety. An increase in the shelf-life of the food products, from an industrial perspective, is essential for transporting and storing processes. Furthermore, since it uses low pressure compared to High Hydrostatic Pressure (HPP), it is cheaper, more user-friendly and it can better preserve the structure and texture of the food product. Furthermore, using a temperature lower than 45°C, it will not alter the molecules in fresh food, preserving the nutritional elements sensitive to temperature and the structure of fresh and processed food. Finally, it works with both conventional food packaging (Polyethylene-PE, Polypropylene-PPE, with proper gas barrier characteristic) or eco-friendly and novel sustainable materials (resistant at the supercritical conditions).
Stage of development
First feasibility and validation studies have been carried out with a lab-scale plant (TRL 4). Through this plant, researchers are able to process up to 4 bags at 100 mL volume each and between 2-50 gram of products in each bag. So far, experiments have been performed on fresh and cut (or whole) fruit and vegetable, meat and fish. Further development will include the process scale up to more industrial oriented product size (100-300 g of treated product). Finally, it will be also important to select the best product category based on the difficulty of preservation and market needs.
Challenge and needs
The International Fresh-Cut Produce Association (IFPA) defines fresh-cut fruits or vegetables as products trimmed, peeled, or cut into 100% usable product bagged or prepackaged to offer the consumer a food with high nutrition, convenience, and flavour although maintaining its freshness. However, it is well known that the steps for ready-to-eat products preparation may promote physiological deteriorations, biochemical changes, and a favourable environment for the proliferation of spoilage microorganisms, even when used with high carefulness during all the production steps.
In addition, raw meat is one of the most perishable foods: its rich physic-chemical composition favours the microbial growth to unacceptable levels.
Hence, research on non-thermal pasteurization technologies has been deeply explored as these technologies accommodate the increased demand for high quality, safe, with fresh appearance and extended shelf-life food products. In this context, the technology in detail kicks in. As a matter of fact, supercritical-CO2 is a promising alternative process, potentially able to inactivate microorganisms in foods with minimal effects on phytochemicals and organoleptic characteristics.
- PCT Patent application NR. WO2019043442 (A1) “Method for food pasteurization”
- Italian Patent NR. 102017000098045 “Metodo per pastorizzare il cibo”
Potential markets and targets
The non-thermal pasteurization market is projected to grow at a CAGR (Compound Annual Growth Rate) of 19.81% to reach USD 2.74 billion by 2023. Within all the applications, the food segment is estimated to dominate this market, while the fruit & vegetable market has the widest subsegment. Moreover, the solid food form segment dominates the global non-thermal pasteurization market, and this is a plus, considering that this technology can be applied to all types of solid products (preferred with a strong firm and/or high internal homogeneity to better resist to the hydrostatic pressure).
Potential partners are any SMEs with interest in food industry. Below, some putative collaboration:
1. food processing and transformation companies interested to test and validate the use of the technology in their specific food products;
2. farms (both organic and conventional sectors) interested to find an innovative and low temperature technique to produce innovative ready-to-eat products and improve their current market;
3. plastic and material companies for packaging to test their material to demonstrate the feasibility of the treatment of specific target products;
4. food plant companies that will help researchers in the process scale-up designing and building a semi-industrial plant.