Design and fabrication of an Electrodynamic Atomization System for food coating
One third of the food meant for human consumption is spoiled every year [1]. This is a cause of great concern for the world where food is already scarce for the ever-growing population. The food can get spoiled at any stage of its production, transportation, or storage. The causes of spoilag
2025-06-28 16:31:32 - Adil Khan
Design and fabrication of an Electrodynamic Atomization System for food coating
Project Area of Specialization Biomedical EngineeringProject SummaryOne third of the food meant for human consumption is spoiled every year [1]. This is a cause of great concern for the world where food is already scarce for the ever-growing population.
The food can get spoiled at any stage of its production, transportation, or storage. The causes of spoilage include Bacteria and various fungi, and the consumption of spoiled food may cause severe health hazards.
In order to contain the problem, we aim to coat the food with different biomaterials for increasing the shelf life of the food so that the food remains fresh and healthier for longer time.
One of the solutions is to design Electrohydrodynamic atomization (EHDA) system. Electrohydrodynamic atomization system provides us with uniform and even coat of polymer on food which increase the shelf life of food.
An electrohydrodynamic atomization (EHDA) system, also called electrospraying machine, is commonly used in pharmaceytical engineering [2] and for controlled drug delivery [3].
The electrohydrodynamic process involves a pumping mechanism that pushes out the solution in a syringe at a controlled rate. The needle of the syringe is connected to the positive terminal of a high-voltage dc power supply. A metal plate connected to the negative terminal of the same power supply, is placed in front of the needle at a distance. This results in the elution of the polymer from the needle in form of nano-sized particles, which are collected on a metal plate or the object placed in front of the collector plate. In this manner, a very fine layer of nano-sized particles is formed on the surface of the metal plate or on the object ahead. In the food industry and in pharmaceutical applications, starch is frequently used because it is tasteless, odorless, colorless, and non-toxic. Other polymers used in different applications as coating include corn zein, and waxes like paraffin, etc.
The bioactive components of food undergo different changes due to heat, light, humidity and oxidation, causing food degradation and decomposition. All this can be avoided by coating a biopolymer over food using an EHDA system.
This projects therefore aims at design, simulation and fabrication of a laboratory scale food coating system based on EHDA. Different EHDA parameters will be simulated, and results will be verified in the fabricated EHDA system.
References
1. Garcha, S (September 2018). "Control of food spoilage molds using lactobacillus bacteriocins". Journal of Pure and Applied Microbiology. 12 (3): 1365–1373
2. Mehta, Prina, et al. "Pharmaceutical and biomaterial engineering via electrohydrodynamic atomization technologies." Drug Discovery Today 22.1 (2017): 157-165.
3. Parhizkar, Maryam, et al. "Electrohydrodynamic encapsulation of cisplatin in poly (lactic-co-glycolic acid) nanoparticles for controlled drug delivery." Nanomedicine: Nanotechnology, Biology and Medicine 12.7 (2016): 1919-1929.
Project ObjectivesOBJECTIVES:
The cost of one lab-scale electro spraying unit is well above Pak Rs. 1 million. Therefore, our project aims at;
- Simulating the process of EHDA system for food coating in order to enhance the shelf life of costly food items like dry fruit.
- Indigenously designing and fabricating a laboratory-scale EHDA system for food coating and training / research.
- Comparing shelf life of food with and without coating.
The first step will help determine suitable parameters to perform food coating using EHDA system. Later, these paramters will be verified and fine tuned in the fabricalted physical system. The estimated cost of the locally made EHDA-based food coating system is within Rs. 100k. The resulting piece of equipment will be later useful in research, training and teaching.
Project Implementation MethodImplementation:
- Using a simulation tool like COMSOL Multiphysics, to understand the effects of volume flow Q, applied voltage V, distance d, and properties of solution (e.g. conductivity K, permittivity ?, concentration of polymer and the solvent, viscosity ?, and surface tension ?) on the size of droplets D of starch, corn zein, and paraffin solutions.
- Designing the EHDA system using 12-30KV power supply, collector as cathode, syringe as anode,
- Fabricating the complete EHDA setup with the right parameters at the department of Biomedical Engineering.
- Preparing solution of zein and paraffins with the desired characteristics.
- Verifying the results from EHDA system with the results of COMSOL Multiphysics.
- Perform food coating.
- Comparing the degradation rate of the food with and without biopolymer coaring.
Benefits:
- The food contains many bioactive compounds like pigments, flavours, enzymes, vitamin etc. those are susceptible to degradation due to light, heat and the presence of oxygen, Electrohydrodynamic atomization is one of the best methods to extend the shelf life these bioactive components.
- guidelines for using the fabricated EHDA unit for teaching / training and research purposes at the Department of Biomedical Engineering.
Technical Details of Final Deliverable
The final deliverable is a laboratory-scale Electrohydrodynamic atomization (EHDA) system that uses strong electrostatic field to break a jet of liquid into a spray of nano-sized droplets. The size of particles depends upon various parameters like the electric field strength and the viscosity of the liquid.
We will use the indigenously developed EHDA for fine coating of food items like dry fruit with zein as the input liquid.
The food items will be coated with the nanoparticles of zein in this well controlled process of EHDA.
This setup of EHDA comprises several major components: a syringe pump, a syringe, a metal needle serving as nozzle, a high voltage power source and a grounded substrate serving as a collector .When the high voltages 10kv-30kv are applied the droplets are formed by the combined effect of both the electrostatic field and the material properties of the polymer solution kept in the syringe and pumped in the opposite direction to the surface tension by increasing the electric potential, the surface tension is overcome and droplets are formed and sprayed onto the food which increases its shelf life. Zein nanoparticles obtained from zein concentrations ranging from 20% to 30% (w/w). The sizes of these particles, ranging from 175 to 900 nm, increased with increasing polymer concentration. Flow rate also exerted an effect, the lower the flow rate the smaller the nanoparticles and has an encapsulation efficiency around 85–90%.
Final Deliverable of the Project Hardware SystemCore Industry FoodOther Industries Education , Health Core Technology OthersOther TechnologiesSustainable Development Goals Good Health and Well-Being for People, Quality EducationRequired Resources| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 80000 | |||
| High Voltage Power supply | Equipment | 1 | 60000 | 60000 |
| Casing | Equipment | 1 | 10000 | 10000 |
| Iron Stand | Miscellaneous | 1 | 1500 | 1500 |
| ethanol | Miscellaneous | 1 | 1000 | 1000 |
| syringes | Miscellaneous | 10 | 50 | 500 |
| Aluminium foil | Miscellaneous | 1 | 350 | 350 |
| Electrodes | Miscellaneous | 4 | 150 | 600 |
| nozzles | Miscellaneous | 15 | 50 | 750 |
| drip set | Miscellaneous | 4 | 100 | 400 |
| zein | Miscellaneous | 1 | 3000 | 3000 |
| stationary | Miscellaneous | 1 | 1900 | 1900 |