Technology

At Mildtech UK Ltd, our technology is designed to revolutionise the way you approach food drying and industrial heating of materials. Leveraging cutting-edge solid-state microwave technology combined with vacuum and intelligent control algorithms, we offer unparalleled control, efficiency, and quality retention across a wide range of applications

How Solid-State Microwave Technology Works

Solid-state microwave technology is at the core of Mildtech’s innovative drying solutions. Unlike traditional magnetron systems, which generate microwaves using high-voltage cathodes, solid-state technology relies on semiconductor devices to produce microwaves. This approach offers several key advantages in terms of precision, efficiency, and control.

Microwave Generation:

Solid-state generators produce microwaves by passing electric currents through semiconductor materials like gallium nitride (GaN) or silicon carbide (SiC). These materials create a stable, continuous wave of microwave energy, which can be finely tuned in terms of frequency and power.

Frequency Control:

One of the major benefits of solid-state technology is its ability to dynamically adjust the frequency of the microwaves. This means that the microwave frequency can be precisely matched to the specific dielectric properties of the material being processed. As the material heats and its properties change, the system can automatically adjust the frequency in real-time to maintain optimal energy transfer.

Uniform Heating:

Solid-state RF generators excite and heat products internally, not just in the outer layers. This bulk heating effect produces uniform heating throughout the material, eliminating the large temperature gradients common in conventional heating systems. By ensuring that water heats first, the process levels the moisture content throughout the product, reducing the risk of surface cracking and ensuring consistent drying quality.

Energy Efficiency:

Solid-state microwaves are highly efficient because they can be directed exactly where they are needed without the energy losses associated with magnetron systems. The ability to continuously adjust power and frequency also means that less energy is wasted, reducing overall consumption.

Reliability and Longevity:

Solid-state generators are known for their reliability and long lifespan. Unlike magnetrons, which degrade over time, solid-state devices maintain consistent performance for years, reducing downtime and maintenance costs.

Solid-State RF Energy

The Mildtech technology uses cutting-edge Solid-State RF power with multiple frequencies combined with vacuum technology to process under mild temperatures much faster and significantly more efficiently than conventional methods.

Solid-State RF generators are able to excite and heat products internally, and not just in the outer layers. The bulk heating effect produces uniform heating throughout the material, avoiding the large temperature gradient that occurs in conventional heating systems. Reduced exposure time to high heat decreases material deterioration; and uniform heating/drying removes the risk of surface cracking (water heats first, resulting in levelling the moisture level).

Combining this with vacuum provides the optimal environment to accelerate the speed of the microwave heating, while avoiding high temperatures.

What Determines the Best Frequency to Use?

The effectiveness of microwave heating depends on several factors, including the material’s dielectric loss factor, which defines how easily the material can be heated by radio frequency. Each material has a specific ideal frequency for heating, and finding this frequency is crucial for optimising the drying process.

Key Factors Influencing Frequency Selection

Dielectric Loss Factor

This is a measure of how easily a material can absorb microwave energy. Materials with higher dielectric loss factors heat more easily, making frequency selection vital for efficient processing.

Power

The amount of microwave power applied directly influences the heating rate of the material.

Product Dimensions

Larger or denser materials may require different frequencies to ensure uniform heating throughout the product.

Frequency

The selected frequency must match the material’s dielectric properties to maximise energy transfer and heating efficiency.

Water Moisture Content

The moisture content in the material plays a significant role in determining the ideal frequency, as water absorbs microwave energy more readily than most other substances.

By dynamically adjusting the frequency based on these factors, Mildtech’s solid-state technology ensures that each material is heated efficiently and uniformly, maximising the quality and speed of the drying process.

Vacuum Technology for Enhanced Performance

As well as using cutting-edge solid-state technology, Mildtech machines incorporate vacuum to further enhance the drying process. The integration of vacuum technology offers several critical benefits that complement the advantages of solid-state microwaves:

Lower Boiling Point

In a vacuum environment, the boiling point of water is significantly reduced-to as low as 15°C. This means that water can be evaporated from the product at much lower temperatures than under normal atmospheric conditions. As a result, sensitive ingredients retain their vital nutrients, flavours, and textures that would otherwise be degraded by higher temperatures.

Accelerated Microwave Heating

Combining solid-state microwave technology with a vacuum provides the optimal environment to accelerate the speed of microwave heating while avoiding the high temperatures that can cause material deterioration. This synergy between vacuum and microwave technology allows for faster processing times without compromising product quality.

Nutrient Retention

The combination of low-temperature drying and vacuum environments ensures that essential vitamins, minerals, and enzymes are preserved. This is especially important for food products, nutraceuticals, and other materials where maintaining the nutritional profile is critical.

Energy Efficiency

The use of vacuum reduces the amount of energy required to evaporate moisture, further enhancing the overall energy efficiency of the drying process. This not only lowers operational costs but also contributes to a more sustainable production process.

Integrated ML & AI

Mildtech’s built-in analytic feature performs real-time monitoring with automatic frequency adjustment, enabling users to create an optimal ‘recipe’ for the processing of a specific product.

The technology also incorporates Machine Learning and Artificial Intelligence to optimise the process, constantly monitoring and adjusting key operating parameters to provide the optimal amount of microwave energy to the target, tuning the frequency and controlling phase over 360 degrees.

To put it simply, Mildtech RF Systems incorporating Machine Learning and AI are able to ‘keep an eye’ on your product so that you don’t have to.

Why Is the Mildtech Technology Better Than Freeze-Drying?

Freeze-drying (lyophilization) has long been considered the gold standard for preserving the nutritional and sensory qualities of food. However, it comes with high energy costs and long processing times. Here’s how Mildtech’s technology outperforms freeze-drying:

Speed: Freeze-drying typically takes 36 hours, whereas Mildtech’s process is significantly faster.

Energy Efficiency: Our technology consumes far less energy than freeze-drying, making it more environmentally friendly and cost-effective.

Nutrient Preservation: Mildtech’s low-temperature drying method retains more nutrients, phytochemicals, and enzymes compared to freeze-drying, which can degrade these essential components.

Testimonials

"The Mildtech process goes further than cooking & drying foods more quickly and at lower temperature which doesn’t destroy the vitamin content, texture and taste; AI is also used to facilitate making healthy food. Thus, Mildtech is able to stay at the forefront of the food sector!"

"An impressive benefit of the Mildtech technology is the reduction in energy required, with up to 80% less energy needed! The reduced energy use contributes to green credentials and showcases social responsibility, helping to contribute to a net-zero food system."

"We achieved a significant improvement in overall efficiency of drying compared to our existing method of freeze drying. Results using the Mildtech technology have been outstanding, whereby the finished product is uniformly dried, very quickly and at very low temperatures."