RF cooking, also known as solid-state cooking, utilizes a high power solid-state amplifier which, as part of a complete RF module, transmits radio wave energy to heat an object in a closed cavity such as an oven. Unlike the typical magnetron in a microwave oven, the digital RF module can accurately control the frequency, amplitude and phase of the radio waves emitted and can also measure reflections. Using Goji’s proprietary closed-feedback system, the RF module control can be optimized to improve the uniformity and consistency of the cooking process. Goji’s design, software and algorithms facilitate meaningful cost reduction in the RF module and significantly shorten integration processes.
When compared with a magnetron source, Goji’s technology provides significantly more
uniform and consistent heating and thawing results. The reduction in occurrence and
magnitude of hotspots and cold spots can significantly improve the quality of the food.
Figure 1(a) and 1(b) below compare thawing uniformity of 1kg (2.2lb) of frozen minced meat in a standard microwave oven with Goji’s RF technology. The same cavity and center frequency of 2.45 GHz was used in both ovens. Though the microwave oven took 33 minutes to reach an optimal result, it still contained 100g (3.5oz) of frozen product and resulted in a peak-to-peak temperature delta of over 10°C in the meat. In contrast, the Goji oven completed the cycle in only 20 minutes (-39% difference) and had no frozen product remaining (-100% difference), while peak-to-peak temperature delta was only 2.5°C (-75% difference).
If you are considering designing products with RF cooking technology, Goji can offer you a range of solutions:
Our experienced team covers all the critical product development disciplines and can help you plan your product roadmap, assist in application evaluation and hardware and software design and license our growing IP portfolio for use in your products. Goji also provides turnkey solutions, including the supply of RF modules (through world-class contract manufacturers) and RF module integration services tailored to your products.
No other company offers our range of services with our expertise and dedication. Whatever your RF technology needs are we would be happy to hear from you and do our most to offer you a high quality and competitive solution.
Dielectric RF heating typically operates within a band of 13 MHz – 6 GHz. Our latest RF module operates in the 2400 – 2500 MHz band.
Yes. When compared with conventional electric ovens, ovens combining RF power with convection heat may save energy thanks to shorter cooking time, which translates to lower energy use by the entire oven.
RF cooking can be integrated in a range of applications including closed cavity structures. Closed cavity structures incorporate a Faraday cage which keeps the RF energy inside – important for safety and compliance with electromagnetic interference regulation. A kitchen oven, for example, may have a suitable cavity structure. Other relevant appliances include bread makers, panini makers, hood-type ovens and other products with a cavity for food preparation.
Goji’s closed-loop feedback algorithm is based on the system’s ability to collect signals reflected from the load (i.e. the food) in the cavity and analyze sample data, using a proprietary algorithm, to calculate optimized heating parameters (frequency, amplitude, phase and time). The process is repeated continuously throughout the cooking process.
While both technologies use radio waves in similar bands, these two technologies differ in almost every other aspect. Magnetrons, used in microwaves, do not have accurate frequency control; in fact, their control is usually limited to being switched on and off. On the other hand, solid-state technology offers accurate control and tuning of frequency, phase and amplitude. Additionally, magnetrons have a limited lifetime as opposed to solid-state technology, which can work around the clock for years. The impact on heating performance is substantial, as summarized in the table:
RF-powered ovens can cook with most utensils, including metal ones, depending on the application. Some metal utensils may not be suitable.
The first oven will be out in Europe next year and subsequently reach the US. Stay posted by signing up to our mailing list below.
In some cases, Goji’s sensing technology can detect food states. In general, the system can recognize different product compositions and states when they have a recurring electromagnetic pattern. For example, as a product defrosts it is possible to detect a phase transition occurring, which is useful for defrost functions. It is also possible to detect when a product finishes baking.
Depending on the amount of a-priori data in the system, Goji’s sensing technology can identify different food compositions and states which may be useful in automating cooking processes and informing users about the state of the food. As part of Goji’s solution, we also offer tailored development services for defined sensing applications.