A Future Road Map for Carbon Dioxide (CO2) Gas Hydrate as an Emerging Technology in Food Research

Gas hydrates constitute of gas as a guest molecule in hydrogen-bonded water lattices. This review covers ongoing hydrate research in food technology with a spotlight on carbon dioxide (CO2) application as a hydrate. The application of gas hydrates in the concentration of juices, desalination, carbonation, and food preservation has been covered in the review. One of the applications of CO2 hydrate technology was in the concentration of orange juice which gave a dehydration ratio (DR) of 57.2% at a pressure of 4.1 MPa. Similarly, one study applied it for the tomato juice concentration and had a DR of 65.2%. The CO2 hydrate rate constants recorded were 0.94 x 10(-8) and 1.65 x 10(-8) J(-1) mol(2) s(-1) at a feed pressure of 1.81 and 3.1 MPa respectively. Hence, CO2 hydrate can be used effectively for the juice concentration as well as for other applications too. The review will cater insights on the generic trends of hydrates in food research with respect to their kinetics properties and their role in food applications. Despite the fact that there are no technology stoppers to exploit CO2 hydrates, a downright technological quantum leap is the need of the future in this riveting field. Thus, the perspectives and key challenges in food research are also discussed. The food applications of CO2 gas hydrates are still very scarce so there is an urge to carry through more theoretical and experimental analysis to elucidate various applications of hydrates in food and to positively validate its sustainability.