Development of a Temperature Food Dehydrator for Sustainable Food Preservation

Abstract

The dehydration of perishable goods remains a critical focus in research and development. Notably, the production processes tailored for small and medium-sized enterprises hold significant importance in this landscape. Such initiatives contribute to the establishment of efficient methodologies for food preservation, enabling improved monitoring and development of dehydration techniques. This Endeavor calls for comprehensive engineering studies. Therefore, the aim of this research was to conceptualize and construct a device specifically designed for consistent vegetable dehydration. Our investigations explored the potential of various machines, highlighting the advantages of utilizing a direct food dehydrator. The findings demonstrate that the production method for the developed direct food drying de hydrator surpasses traditional approaches, which often struggle with maintaining a uniform temperature throughout the drying process.

Introduction

Drying is an ancient food preservation method, with modern techniques including solar drying, heated ovens, and controlled relative humidity. Proper dehydration reduces moisture content, inhibits microbial growth, and preserves taste and nutrition. Traditional sun drying, while common, suffers from contamination risks, space requirements, and inefficiency, motivating the development of more controlled and sustainable methods.

Motivation:
With global population growth threatening food security by 2050, efficient preservation methods like solar drying are essential. Solar dryers offer sustainable, cost-effective, and environmentally friendly solutions, reduce greenhouse gas emissions, add value to agricultural produce, and improve local livelihoods.

Problem Statement:
Open sun drying is inefficient and prone to contamination. Other drying methods (electric, oil-fired) may be costly or unavailable in rural areas. Solar dryers provide a practical, energy-efficient alternative for high-quality food preservation.

Literature Review / Previous Projects:

1. Box-type solar dryer: Air temp 30°C, RH 15%, drying for 10 hours/day.

2. Cylindrical solar dryer: Dehydrated 70 kg of crops; thermal efficiency 18–25%; final moisture content 14%.

3. Intermittent cocoa bean dryer: Moisture reduced from 53.4% to 3.6% over 72 hours.

4. Forced convection solar dryer for copra: Reduced moisture from 51.8% to ~9%; thermal efficiency ~24%.

5. Double-pass solar dryer for chili: Achieved 0.05 moisture content in 23 hours, outperforming cabinet and open sun drying.

6. Hemi-cylindrical solar tunnel dryer for grapes: Reduced moisture from 85% to 16% in 7 days, efficiency 30%.

Proposed Solution:
A solar dehydrator using natural convection removes moisture from various food products while preserving flavor, nutrition, and appearance. Key features include a drying chamber, airflow vents, transparent cover, and food-supporting trays. Sunlight penetrates the chamber, raising air temperature and promoting airflow to efficiently dry food without electricity, reducing energy costs and carbon footprint.

Methodology:

1. Research & Planning: Studied existing solar drying methods and identified critical factors (temperature, humidity, airflow).

2. Design & Prototyping: Developed a detailed drying chamber design with ventilation, trays, and control systems; created prototypes and 3D models.

3. Material Selection & Procurement: Chose durable, thermally efficient, transparent, and reliable materials to ensure effective and long-lasting solar dehydrator construction.

Conclusion

In summary, the heating chamber designed for the solar dehydration system for the project has been shown to fulfill critically the objectives of optimization for efficiency in drying, energy savings, and quality product. Utilizing energy from the sun, it accomplished the required heat input that could extract moisture while minimally relying on nonconventional energy sources and reducing the environmental footprints. The precise control of temperature inside the chamber ensured that the targeted range was constantly maintained throughout the drying process, a consideration that was critical in ensuring the nutritional content, flavour, colour, and texture of the products were preserved [6], [7]. Secondly, the economic efficiency of the heating chamber is remarkable because its application of solar energy greatly minimized the cost of energy, and thus, the drying process became economically viable. Its initial cost was justified by its long-term effectiveness and sustainability. In summary, the importance of the heating chamber in the solar dehydrator system is an aspect that made the effective system. It harnessed solar energy effectively ensured the control of temperature conditions and improved the economic features of the project. This implementation shows good promise for solar heating technology in sustained dehydration processes while maintaining products quality.

References

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Copyright

Copyright © 2025 Tanmay Patle, Mihir Fulari, Abhishek Kumbhar . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.