Water-saving technology for the Preparation of Liquid Food Products
An Italian SME working in the Space field is offering an innovative water-saving technology for the preparation of liquid food products (e.g. coffee, tea, broth). The system allows to clean the ducts and the dispenser from the liquid residuals after each utilization, thus improving the quality of the brewed beverages and being more hygienic. This dispensing assembly minimizes the preparation fluid water losses and does not require any additional actuators with reference to traditional systems
Machines that prepare hot beverages such as tea or coffee from capsules containing the food precursor have become increasingly popular in the last few years. In such a machine, the dispensing assembly is composed of three main elements: the hydraulic system, the control system and the preparation chamber. To prepare the beverage, the capsule is inserted in the preparation chamber and then the preparation fluid is injected where it comes into contact with the dose of the precursor and the final product comes out via a dispensing duct. In this type of devices, it is not rare that water remains in the preparation chamber and in the duct, even after dispensing. To overcome this problem, a particular architecture of the dispensing assembly has been developed. In this architecture, the hydraulic system is composed of two parallel circuits: a hydraulic one and a pneumatic one, which are both controlled by a double-acting pump. The hydraulic system is equipped with the heater and provides hot water/vapour to the preparation chamber. The pneumatic system is equipped with a series of controllable valves that are opened/closed by the control system with a proper timing to store compressed air in a plenum. The air stored in the plenum is released in the preparation chamber, when it is still closed, after that the beverage has been brewed in order to remove any liquid residual. The system is also equipped with sensors to monitor the pressure and with safety features to avoid the risk of over-pressure on both the pneumatic and hydraulic circuits. This dispensing assembly architecture has been applied to ISSpresso, a payload used on the International Space Station to provide espresso coffee to the astronauts: in this way this architecture has been validated in microgravity and it has been implemented with the strict standards required in the space industry.
Innovations & Advantages
The main advantage of this system is cleaning the duct and the preparation chamber after each use, so that there is no fluid left in these areas when the machine is not operating. This has three main advantages:
• Since no water is left in the preparation chamber, there is not the possibility of the accumulation of dirt or bacteria in this area and the system is more hygienic
• All the water used in the preparation of the beverages comes from controlled areas, so no external contaminants are involved in the preparation of the liquid food and its quality is improved
• The losses of the fluid are minimized, and for this reason the machine is more efficient
The achievement off all these advantages is obtained only by means of a combination of hydraulic and pneumatic systems and by simple controllable valves without requiring any additional actuators.
Tests have demonstrated that the patented technology is able to save 30% of water in brewing an espresso coffee if compared with standard coffee brewing systems.
Current and Potential Domains of Application
Space Domestic appliance Food Industry