Open-source Freezedryer

Aim: To develop a technique for manufacturing a sub $1000 small scale freeze dryer that can be built with common and widely available parts and equipment, with a low-cost Raspberry Pi based robotic regulation system with touchscreen, and in addition obtain a Harvest Right Freezedryer and study the machine, components, programming and configuration.

Why it’s important: Freeze-drying is a transformative process in the sense that it allows products to be preserved quickly and then stored without refrigeration for a long time retaining very high nutritional and medicinal content, or aromatic and oleaginous content in the case of cosmetics and body products. It has the potential to save 50%-95% of shipping expenses compared to shipping fresh products and has the potential to save even more on products that are transported under refrigeration. The freeze-drying process is perfect for offering fresh products to the international market that come from remote regions such as the Amazon basin, where vast quantities of fruit go to waste due to a lack of preservation and storage modalities, and will serve both exportation and local food security and nutrition requirements, particularly among indigenous and rural poor populations.

The prohibitive cost of freeze-dryers is the main reason freeze dried products tend to be expensive and fairly uncommon despite their numerous benefits. By creating a manual to build a freeze-dryer it becomes possible for many people that otherwise couldn’t afford one to have one built or build one themselves. By performing a thorough examination of the components used in the Harvest Right Freezedryer, examining the electronics and code and functioning cycles, Alex Daniel will gain valuable knowledge that will help him hugely in developing a method and a manual on how to build a freeze dryer.

Our finished Freezedryer design will be mass produced in surface-extracted light metals, primarily silicon smelted from amazon river sand (SiO2) as a substitute for toxic extractivist aluminium in the main fridge-like cabinet of the Freezedryer.

How it works: Raw or cooked foods are placed in the freeze dryer where they are frozen to between -30 degrees and -50 degrees Fahrenheit. Once frozen, the freeze dryer creates a vacuum in the food chamber. As the food is gradually warmed in the vacuum, the water turns to vapour and evaporates out of the food (sublimation). The resulting product retains all the nutritional value of the original product and has a shelf life of up to 25 years without refrigeration when stored correctly. Once we have freeze dryers, we will be able to preserve high nutrient tropical foods and cosmetics ingredients in hot tropical areas.

Brief Outline of Process: Cut the end off a steel propane tank, retrofit with refrigeration coil on the outside and shelf holders on the inside. Galvanise the tank. Fit with connector for vacuum hose, pressure relief valve and drain valve, make a rubber gasket and a thick polycarbonate door which compresses gasket. Build the refrigeration system to power the coil. Insulate the vacuum chamber and coil with fibreglass and plaster. Set up the electronics with vacuum sensor, humidity sensor and temperature sensor for the shelves and probes for products. Design and program the freeze drying cycle and develop a user interface for making adjustments to the cycle and monitoring progress and sensor data. Finally develop a manual explaining each step of the construction process and creating a user manual and maintenance guide. See what sensors the Harvest Right Freezedryer uses, what components, how the refrigeration system is built, document the freeze drying cycle, examine the coding and interface etc, etc.

Equipment Needed: The Harvest-Right freezedryer, Propane Tank, Coil, Shelves holder, Galvanizing, Shelves, Shelf Heaters, Door, Vacuum Hose, Connections, Drain Valve (manual), Pressure Relief Valve (manual), Pressure Gauge, Vacuum Pump, Steel Frame, Refrigeration system, Compressor, Insulation, Gasket, Electronics, Pi, Sensors, Relays, Wires, Screen, Input

Time: 120 hours research and development, 60 hours assembly and testing, 80 hours writing the manual/documenting the process.

Parts Needed: Propane Tank, Coil, Shelves holder, Galvanizing, Shelves, Shelf Heaters, Door, Vacuum Hose, Connections, Drain Valve (manual), Pressure Relief Valve (manual), Pressure Gauge, Vacuum Pump, Steel Frame, Refrigeration system, Compressor, Insulation, Gasket, Electronics, Pi, Sensors, Relays, Wires, Screen, Input

Time: 120 hours research and development, 60 hours assembly and testing, 80 hours writing the manual/documenting the process