A recent study has explored a new sensor designed to detect adulterants in liquid food products. The researchers behind the study have developed an L-shaped coplanar strip dipole antenna sensor that can identify harmful substances—specifically hydrogen peroxide—in common beverages like milk, mango juice, and pineapple juice. By introducing this technology, the study tackles a major issue in the food industry: ensuring food safety and quality.
Study: L-Shaped Coplanar Strip Dipole Antenna Sensor for Adulteration Detection. Image Credit: Garna Zarina/Shutterstock.com
Background
Food safety is a big deal worldwide, and adulteration remains a serious concern. Some additives make food look better, last longer, or increase profits, but they can also pose health risks. Traditional testing methods can be slow and require specialized equipment, making them impractical for everyday monitoring.
That’s where microwave-based sensors come in. These devices can quickly and accurately detect adulterants by analyzing the electromagnetic properties of food samples. The sensor in this study operates at 2.45 GHz, a frequency that enables wireless sensing and non-invasive testing of liquid samples—ideal for food safety applications.
Study Overview
The research involved several key steps, beginning with the design and optimization of the antenna sensor. Using simulation software, researchers adjusted its dimensions to achieve optimal performance at the target frequency. The sensor was then fabricated using standard photolithography and etching techniques to ensure precision in its construction.
To evaluate its performance, the sensor was tested using a Keysight N5227B PNA Network Analyzer, which measured its reflection characteristics in an anechoic chamber. The researchers conducted experiments with unadulterated milk, pineapple juice, and mango juice, analyzing the sensor’s response at six distinct points within the sensing region. Tests were performed both with and without hydrogen peroxide to assess sensitivity.
Each sample was carefully prepared and placed using a micro-needle to ensure precise positioning within the sensor’s detection area. Multiple trials were conducted over several days using various sensors to validate the reliability and repeatability of the results. This rigorous methodology provided a comprehensive evaluation of the microwave sensor’s capabilities and its potential for food safety applications.
Results and Discussion
The study revealed a strong correlation between sample volume and the resonance frequency shift in the sensor. Sensitivity was recorded as -359.9 MHz/mL for milk, -393.5 MHz/mL for pineapple juice, and -126.9 MHz/mL for mango juice, demonstrating the sensor’s effectiveness in detecting adulterants.
When hydrogen peroxide was introduced, the resonance shift was even more pronounced, further proving the sensor’s ability to detect this specific adulterant. The analysis of reflection characteristics confirmed consistent trends in resonance shifts across multiple trials, reinforcing the importance of repeatability in food safety applications.
These findings highlight the sensor’s potential as a practical tool for food safety monitoring. Its ability to rapidly and accurately detect adulterants could streamline routine food safety checks, making them more efficient and accessible. The study also emphasizes the need for continued research in sensor technology to enhance adulteration detection methods.
The Takeaway
This research presents a significant advancement in food safety through the development of an L-shaped coplanar strip dipole antenna sensor. The study successfully demonstrates the sensor’s ability to detect hydrogen peroxide in liquid food samples, offering a reliable and efficient method for identifying adulterants. With a robust research methodology and promising results, the study underscores the potential of microwave-based sensors in safeguarding food quality.
As the food industry continues to face challenges related to adulteration, integrating cutting-edge sensor technologies will be key to maintaining product integrity and consumer trust. Future research should explore expanding the sensor’s capabilities to detect a broader range of adulterants and apply it to various food matrices, ultimately improving food safety standards on a larger scale.
Journal Reference
Menon SK & Donelli M. (2025). L-Shaped Coplanar Strip Dipole Antenna Sensor for Adulteration Detection. Sensors 25(2):506. DOI: 10.3390/s25020506, https://www.mdpi.com/1424-8220/25/2/506